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ABB RET670 Applications Manual

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Relion
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Transformer protection RET670 ANSI
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Summary of Contents for ABB RET670

  • Page 1 ® Relion 670 series Transformer protection RET670 ANSI Application manual...
  • Page 3 Document ID: 1MRK504116-UUS Issued: February 2015 Revision: C Product version: 1.2 © Copyright 2012 ABB. All rights reserved...
  • Page 4 Copyright This document and parts thereof must not be reproduced or copied without written permission from ABB, and the contents thereof must not be imparted to a third party, nor used for any unauthorized purpose. The software and hardware described in this document is furnished under a license and may be used or disclosed only in accordance with the terms of such license.
  • Page 5 In case any errors are detected, the reader is kindly requested to notify the manufacturer. Other than under explicit contractual commitments, in no event shall ABB be responsible or liable for any loss or damage resulting from the use of this manual or the application of the equipment.
  • Page 6 (EMC Directive 2004/108/EC) and concerning electrical equipment for use within specified voltage limits (Low-voltage directive 2006/95/EC). This conformity is the result of tests conducted by ABB in accordance with the product standards EN 50263 and EN 60255-26 for the EMC directive, and with the product standards EN 60255-1 and EN 60255-27 for the low voltage directive.
  • Page 7: Table Of Contents

    Table of contents Table of contents Section 1 Introduction................15 Introduction to the application manual............15 About the complete set of manuals for an IED........15 About the application manual............16 Intended audience................17 Related documents................17 Revision notes...................17 Section 2 Requirements..............19 Current transformer requirements............19 Current transformer classification............19 Conditions..................20 Fault current..................21 Secondary wire resistance and additional load.........21...
  • Page 8 Table of contents Setting parameters................62 Local human-machine interface..............69 Human machine interface ..............69 Local HMI related functions...............70 Introduction...................70 General setting parameters............70 Indication LEDs.................71 Introduction...................71 Setting parameters...............72 Basic IED functions.................74 Self supervision with internal event list..........74 Application..................74 Setting parameters...............74 Time synchronization.................75 Application..................75 Setting guidelines.................75 Setting parameters...............77 Parameter setting groups..............81...
  • Page 9 Table of contents Setting guidelines.................86 Setting parameters...............86 Signal matrix for binary outputs SMBO ..........86 Application..................87 Setting guidelines.................87 Setting parameters...............87 Signal matrix for mA inputs SMMI.............87 Application..................87 Setting guidelines.................87 Setting parameters...............87 Signal matrix for analog inputs SMAI..........88 Application..................88 Frequency values.................88 Setting guidelines.................89 Setting parameters...............94 Summation block 3 phase 3PHSUM..........95 Application..................95...
  • Page 10 Table of contents Connection examples for high impedance differential protection..................141 Setting guidelines...............144 Setting parameters..............159 Impedance protection ................159 Distance measuring zones, quadrilateral characteristic ZMQPDIS (21), ZMQAPDIS (21), ZDRDIR (21D)......159 Identification................159 Application..................159 Setting guidelines...............177 Setting parameters..............187 Distance measuring zone, quadrilateral characteristic for series compensated lines ZMCPDIS (21), ZMCAPDIS (21), ZDSRDIR (21D)....................189 Application..................189...
  • Page 11 Table of contents Setting parameters..............311 Faulty phase identification with load encroachment FMPSPDIS (21)....................311 Application..................312 Setting guidelines...............312 Setting parameters..............315 Distance protection zone, quadrilateral characteristic, separate settings ZMRPDIS (21), ZMRAPDIS (21) and ZDRDIR (21D)..316 Application..................316 Setting guidelines...............332 Setting parameters..............339 Phase selection, quadrilateral characteristic with settable angle FRPSPDIS (21)................341 Application..................341 Load encroachment characteristics..........347...
  • Page 12 Table of contents Application..................401 Setting guidelines...............403 Setting parameters..............413 Instantaneous residual overcurrent protection EFPIOC (50N)..418 Application..................419 Setting guidelines...............419 Setting parameters..............422 Four step residual overcurrent protection, zero, negative sequence direction EF4PTOC (51N/67N)........422 Application..................422 Setting guidelines...............424 Setting parameters..............435 Four step directional negative phase sequence overcurrent protection NS4PTOC (46I2)............440 Application..................440 Setting guidelines...............442...
  • Page 13 Table of contents Setting guidelines...............487 Setting parameters..............491 Broken conductor check BRCPTOC (46)........493 Application..................493 Setting guidelines...............493 Setting parameters..............494 Capacitor bank protection CBPGAPC..........494 Application..................494 Setting guidelines...............498 Setting parameters..............501 Negativ sequence time overcurrent protection for machines NS2PTOC (46I2)................502 Application..................502 Setting guidelines...............505 Setting parameters..............508 Voltage protection.................509 Two step undervoltage protection UV2PTUV (27)......509 Application..................509...
  • Page 14 Table of contents Frequency protection................542 Underfrequency protection SAPTUF (81)........542 Application..................542 Setting guidelines...............543 Setting parameters..............544 Overfrequency protection SAPTOF (81).........545 Application..................545 Setting guidelines...............545 Setting parameters..............546 Rate-of-change frequency protection SAPFRC (81).......547 Application..................547 Setting guidelines...............547 Setting parameters..............548 Multipurpose protection................549 General current and voltage protection CVGAPC......549 Application..................549 Setting guidelines...............555 Setting parameters..............565...
  • Page 15 Table of contents Configuration guidelines.............617 Interlocking for line bay ABC_LINE (3)........617 Interlocking for bus-coupler bay ABC_BC (3)......623 Interlocking for transformer bay AB_TRAFO (3)......628 Interlocking for bus-section breaker A1A2_BS (3)......630 Interlocking for bus-section disconnector A1A2_DC (3).....633 Interlocking for busbar grounding switch BB_ES (3)....641 Interlocking for double CB bay DB (3)........648 Interlocking for breaker-and-a-half diameter BH (3)....650 Horizontal communication via GOOSE for interlocking...
  • Page 16 Table of contents Scheme communication logic for residual overcurrent protection ECPSCH (85)..............729 Application..................729 Setting guidelines...............730 Setting parameters..............731 Current reversal and weak-end infeed logic for residual overcurrent protection ECRWPSCH (85)........731 Application..................732 Setting guidelines...............733 Setting parameters..............735 Logic.....................735 Tripping logic SMPPTRC (94)............735 Application..................735 Setting guidelines...............740 Setting parameters..............741 Trip matrix logic TMAGGIO.............741...
  • Page 17 Table of contents Measurement...................748 Application..................748 Zero clamping................750 Setting guidelines...............751 Setting parameters..............761 Event counter CNTGGIO..............775 Identification................775 Application..................775 Setting parameters..............775 Event function EVENT..............775 Introduction.................776 Setting guidelines...............776 Setting parameters..............777 Logical signal status report BINSTATREP........779 Application..................779 Setting guidelines...............780 Setting parameters..............780 Measured value expander block RANGE_XP.........780 Application..................780 Setting guidelines...............780 Disturbance report DRPRDRE............780...
  • Page 18 Table of contents Pulse-counter logic PCGGIO............802 Application..................802 Setting guidelines...............803 Setting parameters..............803 Function for energy calculation and demand handling ETPMMTR..................804 Application..................804 Setting guidelines...............805 Setting parameters..............806 Section 4 Station communication............809 Overview....................809 IEC 61850-8-1 communication protocol..........809 Application IEC 61850-8-1...............809 Setting guidelines................811 Setting parameters................811 IEC 61850 generic communication I/O functions SPGGIO, SP16GGIO..................812 Application..................812...
  • Page 19 Section 5 Remote communication.............845 Binary signal transfer................845 Application..................845 Communication hardware solutions...........845 Setting guidelines................847 Setting parameters................849 Section 6 Configuration..............853 Introduction...................853 Description of configuration RET670............854 Introduction..................854 Description of configuration A30..........854 Description of configuration B30..........857 Description of configuration B40..........858 Section 7 Glossary................871 Application manual...
  • Page 21: Section 1 Introduction

    Section 1 1MRK504116-UUS C Introduction Section 1 Introduction About this chapter This chapter introduces the user to the manual as such. Introduction to the application manual 1.1.1 About the complete set of manuals for an IED The user’s manual (UM) is a complete set of five different manuals: Engineeringmanual Installation and Commissioning manual...
  • Page 22: About The Application Manual

    The chapter “Remote communication“ describes the remote end data communication possibilities through binary signal transferring. • The chapter “Configuration” describes the preconfiguration of the IED and its complements. • The chapter “Glossary” is a list of terms, acronyms and abbreviations used in ABB technical documentation. Application manual...
  • Page 23: Intended Audience

    IEC 61850 Data objects list for 670 series 1MRK 500 091-WUS Engineering manual 670 series 1MRK 511 240-UUS Communication set-up for Relion 670 series 1MRK 505 260-UEN More information can be found on www.abb.com/substationautomation. 1.1.5 Revision notes Revision Description Minor corrections made...
  • Page 25: Section 2 Requirements

    Section 2 1MRK504116-UUS C Requirements Section 2 Requirements About this chapter This chapter describes current and voltage transformer requirements. Current transformer requirements The performance of a protection function will depend on the quality of the measured current signal. Saturation of the current transformer (CT) will cause distortion of the current signal and can result in a failure to operate or cause unwanted operations of some functions.
  • Page 26: Conditions

    Section 2 1MRK504116-UUS C Requirements The low remanence type has a specified limit for the remanent flux. This CT is made with a small air gap to reduce the remanence to a level that does not exceed 10% of the saturation flux.
  • Page 27: Fault Current

    Section 2 1MRK504116-UUS C Requirements It is difficult to give general recommendations for additional margins for remanence to avoid the minor risk of an additional time delay. They depend on the performance and economy requirements. When current transformers of low remanence type (for example, TPY, PR) are used, normally no additional margin is needed.
  • Page 28: General Current Transformer Requirements

    CT (TPZ) is not well defined as far as the phase angle error is concerned. If no explicit recommendation is given for a specific function we therefore recommend contacting ABB to confirm that the non remanence type can be used. The CT requirements for the different functions below are specified as a rated equivalent limiting secondary e.m.f.
  • Page 29: Distance Protection

    Section 2 1MRK504116-UUS C Requirements æ ö × ³ = × × ç ÷ a lre q è ø (Equation 2) EQUATION1673 V1 EN where: The rated primary current of the power transformer (A) Maximum primary fundamental frequency current that passes two main CTs and the power transformer (A) The rated primary CT current (A) The rated secondary CT current (A)
  • Page 30: Restricted Ground Fault Protection (Low Impedance Differential)

    Section 2 1MRK504116-UUS C Requirements × æ ö ³ k ma x × ç ÷ a lre q è ø (Equation 4) EQUATION1675 V1 EN × æ ö ³ kzone 1 × ç ÷ a lre q è ø (Equation 5) EQUATION1676 V1 EN where: Maximum primary fundamental frequency current for close-in forward and...
  • Page 31 Section 2 1MRK504116-UUS C Requirements Neutral CTs and phase CTs for solidly ground transformers The neutral CT and the phase CTs must have a rated equivalent secondary e.m.f. E that is larger than or equal to the maximum of the required secondary e.m.f. E below: alreq æ...
  • Page 32 Section 2 1MRK504116-UUS C Requirements Neutral CTs and phase CTs for impedance grounded transformers The neutral CT and phase CTs must have a rated equivalent secondary e.m.f. E that is larger than or equal to the required secondary e.m.f. E below: alreq æ...
  • Page 33: Current Transformer Requirements For Cts According To Other Standards

    Section 2 1MRK504116-UUS C Requirements connection) for example, in substations with breaker-and-a-half or double-busbar double- breaker arrangement or if the transformer has a T-connection to different busbars, there is a risk that the CTs can be exposed for higher fault currents than the considered phase- to-ground fault currents above.
  • Page 34: Current Transformers According To Iec 60044-1, Class Px, Iec 60044-6, Class Tps (And Old British Standard, Class X)

    Section 2 1MRK504116-UUS C Requirements > 2 max alreq (Equation 11) EQUATION1383 V2 EN 2.1.7.2 Current transformers according to IEC 60044-1, class PX, IEC 60044-6, class TPS (and old British Standard, class X) CTs according to these classes are specified approximately in the same way by a rated knee-point e.m.f.
  • Page 35: Voltage Transformer Requirements

    Section 2 1MRK504116-UUS C Requirements The CTs according to class C must have a calculated rated equivalent limiting secondary e.m.f. E that fulfills the following: alANSI > max imum of E alANSI alreq (Equation 14) EQUATION1384 V1 EN A CT according to ANSI/IEEE is also specified by the knee-point voltage V kneeANSI that is graphically defined from an excitation curve.
  • Page 36: Iec 61850-9-2Le Merging Unit Requirements

    Section 2 1MRK504116-UUS C Requirements software. The SNTP server should be stable, that is, either synchronized from a stable source like GPS, or local without synchronization. Using a local SNTP server without synchronization as primary or secondary server in a redundant configuration is not recommended.
  • Page 37: Section 3 Ied Application

    General IED application RET670 provides fast and selective protection, monitoring and control for two- and three- winding transformers, autotransformers, generator-transformer units, phase shifting transformers, special railway transformers and shunt reactors. The transformer IED is...
  • Page 38 Out of Step function is available to separate power system sections close to electrical centre at occurring out of step. RET670 can be used in applications with the IEC 61850-9-2LE process bus with up to two Merging Units (MU). Each MU has eight analogue channels, normally four current and four voltages.
  • Page 39: Analog Inputs

    Section 3 1MRK504116-UUS C IED application The wide application flexibility makes this product an excellent choice for both new installations and the refurbishment of existing installations. Analog inputs 3.2.1 Introduction Analog input channels must be configured and set properly to get correct measurement results and correct protection operations.
  • Page 40 Section 3 1MRK504116-UUS C IED application Setting of current channels The direction of a current to the IED is depending on the connection of the CT. Unless indicated otherwise, the main CTs are supposed to be Wye (star) connected and can be connected with the grounding point to the object or from the object.
  • Page 41 Section 3 1MRK504116-UUS C IED application Line Transformer Line Reverse Forward Definition of direction for directional functions Transformer protection Line protection Setting of current input: Setting of current input: Setting of current input: Set parameter Set parameter Set parameter CT_WyePoint with CT_WyePoint with CT_WyePoint with Transformer as...
  • Page 42 Section 3 1MRK504116-UUS C IED application Transformer Line Forward Reverse Definition of direction for directional Transformer and line functions Line protection Setting of current input: Setting of current input: Set parameter Set parameter CT_WyePoint with CT_WyePoint with Transformer as Transformer as reference object.
  • Page 43 Section 3 1MRK504116-UUS C IED application line and transformer protection functions are configured to the different inputs. The CT direction for the current channels to the line protection is set with the line as reference object and the directional functions of the line protection shall be set to Forward to protect the line.
  • Page 44 Section 3 1MRK504116-UUS C IED application Busbar Busbar Protection en06000196_ansi.vsd ANSI06000196 V1 EN Figure 6: Example how to set CT_WyePoint parameters in the IED For busbar protection it is possible to set the CT_WyePoint parameters in two ways. The first solution will be to use busbar as a reference object. In that case for all CT inputs marked with 1 in figure 6, set CT_WyePoint = ToObject, and for all CT inputs marked with 2 in figure 6, set CT_WyePoint = FromObject.
  • Page 45 Section 3 1MRK504116-UUS C IED application Regardless which one of the above two options is selected busbar differential protection will behave correctly. The main CT ratios must also be set. This is done by setting the two parameters CTsec and CTprim for each current channel. For a 1000/5 A CT the following setting shall be used: •...
  • Page 46 Section 3 1MRK504116-UUS C IED application It shall be noted that depending on national standard and utility practices, the rated secondary current of a CT has typically one of the following values: • • However in some cases the following rated secondary currents are used as well: •...
  • Page 47 Section 3 1MRK504116-UUS C IED application SMAI_20 CT 600/5 Star Connected ANSI3000002-2-en.vsd Protected Object ANSI13000002 V2 EN Figure 8: Wye connected three-phase CT set with wye point towards the protected object Where: The drawing shows how to connect three individual phase currents from a wye connected three- phase CT set to the three CT inputs of the IED.
  • Page 48 Section 3 1MRK504116-UUS C IED application These three connections are the links between the three current inputs and the three input channels of the preprocessing function block 4). Depending on the type of functions, which need this current information, more than one preprocessing block might be connected in parallel to the same three physical CT inputs.
  • Page 49 Section 3 1MRK504116-UUS C IED application SMAI_20_2 BLOCK AI3P REVROT ^GRP2L1 ^GRP2L2 ^GRP2L3 CT 800/1 ^GRP2N Star Connected ANSI11000026-4-en.vsd Protected Object ANSI11000026 V4 EN Figure 9: Wye connected three-phase CT set with its star point away from the protected object In the example in figure 9 case everything is done in a similar way as in the above...
  • Page 50 Section 3 1MRK504116-UUS C IED application SMAI2 BLOCK AI3P AI 01 (I) ^GRP2_A ^GRP2_B ^GRP2_C AI 02 (I) ^GRP2N TYPE AI 03 (I) CT 800/1 Wye Connected AI 04 (I) AI 05 (I) AI 06 (I) Protected Object ANSI06000644-2-en.vsd ANSI06000644 V2 EN Figure 10: Wye connected three-phase CT set with its star point away from the protected object and the residual/ neutral current connected to the IED...
  • Page 51 Section 3 1MRK504116-UUS C IED application is a connection made in the Signal Matrix tool (SMT), Application configuration tool (ACT), which connects the residual/neutral current input to the fourth input channel of the preprocessing function block 6). Note that this connection in SMT shall not be done if the residual/ neutral current is not connected to the IED.
  • Page 52 Section 3 1MRK504116-UUS C IED application SMAI_20 IA-IB IB-IC IC-IA ANSI11000027-2-en.vsd Protected Object ANSI11000027 V2 EN Figure 11: Delta DAB connected three-phase CT set Application manual...
  • Page 53 Section 3 1MRK504116-UUS C IED application Where: shows how to connect three individual phase currents from a delta connected three-phase CT set to three CT inputs of the IED. is the TRM where these current inputs are located. It shall be noted that for all these current inputs the following setting values shall be entered.
  • Page 54 Section 3 1MRK504116-UUS C IED application SMAI_20 IA-IC IB-IA IC-IB ANSI11000028-2-en.vsd Protected Object ANSI11000028 V2 EN Figure 12: Delta DAC connected three-phase CT set In this case, everything is done in a similar way as in the above described example, except that for all used current inputs on the TRM the following setting parameters shall be entered: =800A...
  • Page 55 Section 3 1MRK504116-UUS C IED application For correct terminal designations, see the connection diagrams valid for the delivered IED. Protected Object SMAI_20_2 BLOCK AI3P REVROT ^GRP2_A ^GRP2_B ^GRP2_C ^GRP2_N ANSI11000029-3-en.vsd ANSI11000029 V3 EN Figure 13: Connections for single-phase CT input Application manual...
  • Page 56 Section 3 1MRK504116-UUS C IED application Where: shows how to connect single-phase CT input in the IED. is TRM where these current inputs are located. It shall be noted that for all these current inputs the following setting values shall be entered. For connection (a) shown in figure 13: CT prim = 1000 A CT sec = 1A...
  • Page 57 Section 3 1MRK504116-UUS C IED application (X1) (X1) (X1) (H1) (H1) (H1) (H2) (X2) (H2) (X2) (H2) (X2) ANSI11000175_1_en.vsd ANSI11000175 V1 EN Figure 14: Commonly used markings of VT terminals Where: is the symbol and terminal marking used in this document. Terminals marked with a dot indicate the primary and secondary winding terminals with the same (positive) polarity is the equivalent symbol and terminal marking used by IEC (ANSI) standard for phase-to- ground connected VTs...
  • Page 58 Section 3 1MRK504116-UUS C IED application AI 07 (I) SMAI2 BLOCK AI3P AI 08 (V) ^GRP2_A ^GRP2_B AI 09 (V) ^GRP2_C ^GRP2N #Not used AI 10 (V) TYPE AI 11 (V) AI 12 (V) ANSI06000599-2-en.vsd ANSI06000599 V2 EN Figure 15: A Three phase-to-ground connected VT Where: shows how to connect three secondary phase-to-ground voltages to three VT inputs on the...
  • Page 59 Section 3 1MRK504116-UUS C IED application are three connections made in Signal Matrix Tool (SMT), which connect these three voltage inputs to first three input channels of the preprocessing function block 5). Depending on the type of functions which need this voltage information, more then one preprocessing block might be connected in parallel to these three VT inputs.
  • Page 60 Section 3 1MRK504116-UUS C IED application 13.8 13.8 AI 07(I) SMAI2 BLOCK AI3P AI 08 (V) ^GRP2_A (A-B) ^GRP2_B (B-C) AI 09 (V) ^GRP2_C (C-A) ^GRP2N #Not Used TYPE AI 10(V) AI 11(V) AI 12(V) ANSI06000600-3-en.vsd ANSI06000600 V3 EN Figure 16: A Two phase-to-phase connected VT Where: shows how to connect the secondary side of a phase-to-phase VT to the VT inputs on the IED...
  • Page 61 Section 3 1MRK504116-UUS C IED application are three connections made in the Signal Matrix tool (SMT), Application configuration tool (ACT), which connects these three voltage inputs to first three input channels of the preprocessing function block 5). Depending on the type of functions, which need this voltage information, more than one preprocessing block might be connected in parallel to these three VT inputs shows that in this example the fourth (that is, residual) input channel of the preprocessing block...
  • Page 62 Section 3 1MRK504116-UUS C IED application AI 07 (I) AI 08 (V) SMAI2 AI 09 (V) BLOCK AI3P ^GRP2_A # Not Used AI 10 (V) ^GRP2_B # Not Used ^GRP2_C # Not Used AI 11 (V) +3Vo ^GRP2N TYPE AI 12 (V) ANSI06000601-2-en.vsd ANSI06000601 V2 EN Figure 17:...
  • Page 63 Section 3 1MRK504116-UUS C IED application Where: shows how to connect the secondary side of the open delta VT to one VT input on the IED. +3Vo shall be connected to the IED is the TRM where this voltage input is located. It shall be noted that for this voltage input the following setting values shall be entered: ×...
  • Page 64 Section 3 1MRK504116-UUS C IED application Example how to connect the open delta VT to the IED for low impedance grounded or solidly grounded power systems Figure gives an example about the connection of an open delta VT to the IED for low impedance grounded or solidly grounded power systems.
  • Page 65 Section 3 1MRK504116-UUS C IED application AI07 (I) AI08 (V) SMAI2 AI09 (V) BLOCK AI3P ^GRP2_A # Not Used AI10 (V) # Not Used ^GRP2_B # Not Used ^GRP2_C +3Vo AI11 (V) ^GRP2N TYPE AI12 (V) ANSI06000602-2-en.vsd ANSI06000602 V2 EN Figure 18: Open delta connected VT in low impedance or solidly grounded power system Application manual...
  • Page 66 Section 3 1MRK504116-UUS C IED application Where: shows how to connect the secondary side of open delta VT to one VT input in the IED. +3Vo shall be connected to the IED. is TRM where this voltage input is located. It shall be noted that for this voltage input the following setting values shall be entered: ×...
  • Page 67 Section 3 1MRK504116-UUS C IED application Example on how to connect a neutral point VT to the IED Figure gives an example on how to connect a neutral point VT to the IED. This type of VT connection presents secondary voltage proportional to V to the IED.
  • Page 68: Setting Parameters

    Section 3 1MRK504116-UUS C IED application Where: shows how to connect the secondary side of neutral point VT to one VT input in the IED. shall be connected to the IED. is the TRM or AIM where this voltage input is located. For this voltage input the following setting values shall be entered: VTprim 3.81...
  • Page 69 Section 3 1MRK504116-UUS C IED application Table 1: AISVBAS Non group settings (basic) Name Values (Range) Unit Step Default Description PhaseAngleRef TRM40-Ch1 TRM40-Ch1 Reference channel for phase angle TRM40-Ch2 presentation TRM40-Ch3 TRM40-Ch4 TRM40-Ch5 TRM40-Ch6 TRM40-Ch7 TRM40-Ch8 TRM40-Ch9 TRM40-Ch10 TRM40-Ch11 TRM40-Ch12 TRM41-Ch1 TRM41-Ch2 TRM41-Ch3...
  • Page 70 Section 3 1MRK504116-UUS C IED application Table 2: TRM_12I Non group settings (basic) Name Values (Range) Unit Step Default Description CT_WyePoint1 FromObject ToObject ToObject= towards protected object, ToObject FromObject= the opposite CTsec1 1 - 10 Rated CT secondary current CTprim1 1 - 99999 3000 Rated CT primary current...
  • Page 71 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description CTprim10 1 - 99999 3000 Rated CT primary current CT_WyePoint11 FromObject ToObject ToObject= towards protected object, ToObject FromObject= the opposite CTsec11 1 - 10 Rated CT secondary current CTprim11 1 - 99999 3000...
  • Page 72 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description VTprim8 0.05 - 2000.00 0.05 400.00 Rated VT primary voltage VTsec9 0.001 - 999.999 0.001 110.000 Rated VT secondary voltage VTprim9 0.05 - 2000.00 0.05 400.00 Rated VT primary voltage VTsec10 0.001 - 999.999 0.001...
  • Page 73 Section 3 1MRK504116-UUS C IED application Table 5: TRM_7I_5U Non group settings (basic) Name Values (Range) Unit Step Default Description CT_WyePoint1 FromObject ToObject ToObject= towards protected object, ToObject FromObject= the opposite CTsec1 1 - 10 Rated CT secondary current CTprim1 1 - 99999 3000 Rated CT primary current...
  • Page 74 Section 3 1MRK504116-UUS C IED application Table 6: TRM_9I_3U Non group settings (basic) Name Values (Range) Unit Step Default Description CT_WyePoint1 FromObject ToObject ToObject= towards protected object, ToObject FromObject= the opposite CTsec1 1 - 10 Rated CT secondary current CTprim1 1 - 99999 3000 Rated CT primary current...
  • Page 75: Local Human-Machine Interface

    Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description VTprim11 0.05 - 2000.00 0.05 400.00 Rated VT primary voltage VTsec12 0.001 - 999.999 0.001 110.000 Rated VT secondary voltage VTprim12 0.05 - 2000.00 0.05 400.00 Rated VT primary voltage Local human-machine interface 3.3.1 Human machine interface...
  • Page 76: Local Hmi Related Functions

    Section 3 1MRK504116-UUS C IED application IEC07000077 V1 EN Figure 20: Medium graphic HMI, 15 controllable objects 3.3.2 Local HMI related functions 3.3.2.1 Introduction The local HMI can be adapted to the application configuration and to user preferences. • Function block LocalHMI •...
  • Page 77: Indication Leds

    Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description DefaultScreen 0 - 0 Default screen EvListSrtOrder Latest on top Latest on top Sort order of event list Oldest on top SymbolFont Symbol font for Single Line Diagram ANSI 3.3.3 Indication LEDs...
  • Page 78: Setting Parameters

    Section 3 1MRK504116-UUS C IED application 3.3.3.2 Setting parameters Table 8: LEDGEN Non group settings (basic) Name Values (Range) Unit Step Default Description Operation Disabled Disabled Operation mode for the LED function Enabled tRestart 0.0 - 100.0 Defines the disturbance length tMax 0.0 - 100.0 Maximum time for the definition of a...
  • Page 79 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description SeqTypeLED8 Follow-S Follow-S sequence type for LED 8 Follow-F LatchedAck-F-S LatchedAck-S-F LatchedColl-S LatchedReset-S SeqTypeLED9 Follow-S Follow-S Sequence type for LED 9 Follow-F LatchedAck-F-S LatchedAck-S-F LatchedColl-S LatchedReset-S SeqTypeLED10 Follow-S Follow-S Sequence type for LED 10...
  • Page 80: Basic Ied Functions

    Section 3 1MRK504116-UUS C IED application Basic IED functions 3.4.1 Self supervision with internal event list 3.4.1.1 Application The protection and control IEDs have many functions included . The included self- supervision with internal event list function block provides good supervision of the IED.
  • Page 81: Time Synchronization

    Section 3 1MRK504116-UUS C IED application 3.4.2 Time synchronization 3.4.2.1 Application Use time synchronization to achieve a common time base for the IEDs in a protection and control system. This makes it possible to compare events and disturbance data between all IEDs in the system. Time-tagging of internal events and disturbances are an excellent help when evaluating faults.
  • Page 82 Section 3 1MRK504116-UUS C IED application TimeSynch When the source of the time synchronization is selected on the local HMI, the parameter is called TimeSynch. The time synchronization source can also be set from PCM600. The setting alternatives are: FineSyncSource which can have the following values: •...
  • Page 83: Setting Parameters

    Section 3 1MRK504116-UUS C IED application The parameter SyncMaster defines if the IED is a master, or not a master for time synchronization in a system of IEDs connected in a communication network (IEC61850-8-1). The SyncMaster can have the following values: •...
  • Page 84 Section 3 1MRK504116-UUS C IED application Table 9: TIMESYNCHGEN Non group settings (basic) Name Values (Range) Unit Step Default Description CoarseSyncSrc Disabled Disabled Coarse time synchronization source SNTP FineSyncSource Disabled Disabled Fine time synchronization source GPS+SPA GPS+LON GPS+BIN SNTP GPS+SNTP IRIG-B GPS+IRIG-B SyncMaster...
  • Page 85 Section 3 1MRK504116-UUS C IED application Table 12: DSTBEGIN Non group settings (basic) Name Values (Range) Unit Step Default Description MonthInYear January March Month in year when daylight time starts February March April June July August September October November December DayInWeek Sunday Sunday...
  • Page 86 Section 3 1MRK504116-UUS C IED application Table 13: DSTEND Non group settings (basic) Name Values (Range) Unit Step Default Description MonthInYear January October Month in year when daylight time ends February March April June July August September October November December DayInWeek Sunday Sunday...
  • Page 87: Parameter Setting Groups

    Section 3 1MRK504116-UUS C IED application 3.4.3 Parameter setting groups 3.4.3.1 Application Six sets of settings are available to optimize IED operation for different power system conditions. By creating and switching between fine tuned setting sets, either from the local HMI or configurable binary inputs, results in a highly adaptable IED that can cope with a variety of power system scenarios.
  • Page 88: Test Mode Functionality Test

    Section 3 1MRK504116-UUS C IED application Table 17: SETGRPS Non group settings (basic) Name Values (Range) Unit Step Default Description ActiveSetGrp SettingGroup1 SettingGroup1 ActiveSettingGroup SettingGroup2 SettingGroup3 SettingGroup4 SettingGroup5 SettingGroup6 MAXSETGR 1 - 6 Max number of setting groups 1-6 3.4.4 Test mode functionality TEST 3.4.4.1 Application...
  • Page 89: Application

    CHNGLCK input, that logic must be designed so that it cannot permanently issue a logical one to the CHNGLCK input. If such a situation would occur in spite of these precautions, then please contact the local ABB representative for remedial action. Application manual...
  • Page 90: Setting Parameters

    Section 3 1MRK504116-UUS C IED application 3.4.5.2 Setting parameters Table 19: CHNGLCK Non group settings (basic) Name Values (Range) Unit Step Default Description Operation LockHMI and Com LockHMI and Com Operation mode of change lock LockHMI, EnableCom EnableHMI, LockCom 3.4.6 IED identifiers 3.4.6.1 Application...
  • Page 91: Setting Parameters

    Section 3 1MRK504116-UUS C IED application • IEDProdType • ProductDef • FirmwareVer • SerialNo • OrderingNo • ProductionDate The settings are visible on the local HMI , under Main menu/Diagnostics/IED status/ Product identifiers They are very helpful in case of support process (such as repair or maintenance). 3.4.7.2 Setting parameters The function does not have any parameters available in the local HMI or PCM600.
  • Page 92: Application

    Section 3 1MRK504116-UUS C IED application 3.4.8.1 Application The rated system frequency is set under Main menu/General settings/ Power system/ Primary Values in the local HMI and PCM600 parameter setting tree. 3.4.8.2 Setting guidelines Set the system rated frequency. Refer to section "Signal matrix for analog inputs SMAI"...
  • Page 93: Application

    Section 3 1MRK504116-UUS C IED application 3.4.10.1 Application The Signal matrix for binary outputs function SMBO is used within the Application Configuration tool in direct relation with the Signal Matrix tool. SMBO represents the way binary outputs are sent from one IED configuration. It is important that SMBO inputs are connected when SMBOs are connected to physical outputs through the Signal Matrix Tool.
  • Page 94: Signal Matrix For Analog Inputs Smai

    Section 3 1MRK504116-UUS C IED application 3.4.12 Signal matrix for analog inputs SMAI 3.4.12.1 Application Signal matrix for analog inputs function (SMAI), also known as the preprocessor function, processes the analog signals connected to it and gives information about all aspects of the analog signals connected, like the RMS value, phase angle, frequency, harmonic content, sequence components and so on.
  • Page 95: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application setting must still be Ph-Ph and this has to be accounted for when setting IntBlockLevel. If SMAI setting ConnectionType is Ph-N and the same voltage is connected to all three SMAI inputs, the positive sequence voltage will be zero and the frequency functions will not work properly.
  • Page 96 Section 3 1MRK504116-UUS C IED application ConnectionType: Connection type for that specific instance (n) of the SMAI (if it is Ph- N or Ph-Ph). Depending on connection type setting the not connected Ph-N or Ph-Ph outputs will be calculated. Negation: If the user wants to negate the 3ph signal, it is possible to choose to negate only the phase signals Negate3Ph, only the neutral signal NegateN or both Negate3Ph +N.
  • Page 97 Section 3 1MRK504116-UUS C IED application Task time group 1 SMAI instance 3 phase group SMAI1:1 SMAI2:2 SMAI3:3 AdDFTRefCh7 SMAI4:4 SMAI5:5 SMAI6:6 SMAI7:7 SMAI8:8 SMAI9:9 SMAI10:10 SMAI11:11 SMAI12:12 Task time group 2 SMAI instance 3 phase group SMAI1:13 AdDFTRefCh4 SMAI2:14 SMAI3:15 SMAI4:16 SMAI5:17...
  • Page 98 Section 3 1MRK504116-UUS C IED application Example 1 SMAI1:13 BLOCK SPFCOUT DFTSPFC AI3P ^GRP1_A ^GRP1_B ^GRP1_C SMAI1:1 ^GRP1_N BLOCK SPFCOUT TYPE DFTSPFC AI3P ^GRP1_A ^GRP1_B ^GRP1_C ^GRP1_N TYPE SMAI1:25 BLOCK SPFCOUT DFTSPFC AI3P ^GRP1_A ^GRP1_B ^GRP1_C ^GRP1_N TYPE ANSI07000198.vsd ANSI07000198 V1 EN Figure 23: Configuration for using an instance in task time group 1 as DFT reference Assume instance SMAI7:7 in task time group 1 has been selected in the configuration...
  • Page 99 Section 3 1MRK504116-UUS C IED application SMAI1:1 BLOCK SPFCOUT DFTSPFC AI3P ^GRP1_A ^GRP1_B ^GRP1_C SMAI1:13 ^GRP1_N BLOCK SPFCOUT TYPE DFTSPFC AI3P ^GRP1_A ^GRP1_B ^GRP1_C ^GRP1_N TYPE SMAI1:25 BLOCK SPFCOUT DFTSPFC AI3P ^GRP1_A ^GRP1_B ^GRP1_C ^GRP1_N TYPE ANSI07000198.vsd ANSI07000199 V1 EN Figure 24: Configuration for using an instance in task time group 2 as DFT reference.
  • Page 100: Setting Parameters

    Section 3 1MRK504116-UUS C IED application 3.4.12.4 Setting parameters Table 22: SMAI1 Non group settings (basic) Name Values (Range) Unit Step Default Description DFTRefExtOut InternalDFTRef InternalDFTRef DFT reference for external output AdDFTRefCh1 AdDFTRefCh2 AdDFTRefCh3 AdDFTRefCh4 AdDFTRefCh5 AdDFTRefCh6 AdDFTRefCh7 AdDFTRefCh8 AdDFTRefCh9 AdDFTRefCh10 AdDFTRefCh11 AdDFTRefCh12...
  • Page 101: Summation Block 3 Phase 3Phsum

    Section 3 1MRK504116-UUS C IED application Table 24: SMAI2 Non group settings (basic) Name Values (Range) Unit Step Default Description DFTReference InternalDFTRef InternalDFTRef DFT reference AdDFTRefCh1 AdDFTRefCh2 AdDFTRefCh3 AdDFTRefCh4 AdDFTRefCh5 AdDFTRefCh6 AdDFTRefCh7 AdDFTRefCh8 AdDFTRefCh9 AdDFTRefCh10 AdDFTRefCh11 AdDFTRefCh12 External DFT ref ConnectionType Ph-N Ph-N...
  • Page 102: Setting Parameters

    Section 3 1MRK504116-UUS C IED application DFTReference: The reference DFT block (InternalDFT Ref,DFTRefGrp1 or External DFT ref) . FreqMeasMinVal: The minimum value of the voltage for which the frequency is calculated, expressed as percent of VBasebase voltage setting (for each instance x). VBase: Base voltage setting.
  • Page 103: Setting Parameters

    Section 3 1MRK504116-UUS C IED application 3.4.14.2 Setting parameters The function does not have any parameters available in the local HMI or PCM600. 3.4.15 Denial of service DOS 3.4.15.1 Application The denial of service functions (DOSFRNT, DOSOEMAB and DOSOEMCD) are designed to limit the CPU load that can be produced by Ethernet network traffic on the IED.
  • Page 104: Application

    Section 3 1MRK504116-UUS C IED application Function description IEC 61850 IEC 60617 ANSI/IEEE C37.2 identification identification device number Transformer differential protection, two- T2WPDIF winding 3Id/I SYMBOL-BB V1 EN Transformer differential protection, T3WPDIF three-winding 3Id/I SYMBOL-BB V1 EN 3.5.1.1 Application The transformer differential protection is a unit protection. It serves as the main protection of transformers in case of winding failure.
  • Page 105: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application implemented in the IED compensates for both the turns-ratio and the phase shift internally in the software. No auxiliary current transformers are necessary. The differential current should theoretically be zero during normal load or external faults if the turn-ratio and the phase shift are correctly compensated.
  • Page 106 Section 3 1MRK504116-UUS C IED application transformers have difficult operating conditions. This bias quantity gives the best stability against an unwanted operation during external faults. The usual practice for transformer protection is to set the bias characteristic to a value of at least twice the value of the expected spill current under through faults conditions.
  • Page 107 Section 3 1MRK504116-UUS C IED application The unrestrained operation level has a default value of IdUnre = 10pu, which is typically acceptable for most of the standard power transformer applications. In the following case, this setting need to be changed accordingly: •...
  • Page 108 Section 3 1MRK504116-UUS C IED application operate current [ times IBase ] Operate unconditionally UnrestrainedLimit Operate conditionally Section 1 Section 2 Section 3 SlopeSection3 IdMin SlopeSection2 Restrain EndSection1 restrain current [ times IBase ] EndSection2 en05000187-2.vsd IEC05000187 V2 EN Figure 25: Representation of the restrained-, and the unrestrained operate characteristics Ioperate...
  • Page 109 Section 3 1MRK504116-UUS C IED application Elimination of zero sequence currents A differential protection may operate unwanted due to external ground-faults in cases where the zero sequence current can flow on only one side of the power transformer. but not on the other side. This is the case when zero sequence current cannot be properly transformed to the other side of the power transformer.
  • Page 110 Section 3 1MRK504116-UUS C IED application up transformers in power stations) should be provided with an overexcitation protection based on V/Hz to achieve a trip before the core thermal limit is reached. Cross-blocking between phases Basic definition of the cross-blocking is that one of the three phases can block operation (that is, tripping) of the other two phases due to the harmonic pollution of the differential current in that phase (waveform, 2nd or 5th harmonic content).
  • Page 111 Section 3 1MRK504116-UUS C IED application The setting NegSeqROA represents the so-called Relay Operate Angle, which determines the boundary between the internal and external fault regions. It can be selected in the range from 30 degrees to 90 degrees, with a step of 1 degree. The default value is 60 degrees.
  • Page 112 Section 3 1MRK504116-UUS C IED application The principle of the internal/external fault discriminator can be extended to autotransformers and transformers with three windings. If all three windings are connected to their respective networks then three directional comparisons are made, but only two comparisons are necessary in order to positively determine the position of the fault with respect to the protected zone.
  • Page 113 Section 3 1MRK504116-UUS C IED application Differential current alarm Differential protection continuously monitors the level of the fundamental frequency differential currents and gives an alarm if the pre-set value is simultaneously exceeded in all three phases. This feature can be used to monitor the integrity of on-load tap- changer compensation within the differential function.
  • Page 114: Setting Example

    Section 3 1MRK504116-UUS C IED application enabled it is not possible to test the 2 harmonic blocking feature by simply injecting one current with superimposed second harmonic. In that case the switch on to fault feature will operate and the differential protection will trip. However for a real inrush case the differential protection function will properly restrain from operation.
  • Page 115 Section 3 1MRK504116-UUS C IED application noted that irrespective of the main CT connections (wye or delta) on-line reading and automatic compensation for actual load tap changer position can be used in the IED. Typical main CT connections for transformer differential protection Three most typical main CT connections used for transformer differential protection are shown in figure 26.
  • Page 116 Section 3 1MRK504116-UUS C IED application • are increased √3 times (1.732 times) in comparison with wye connected CTs • lag by 30° the primary winding currents (this CT connection rotates currents by 30° in clockwise direction) • do not contain zero sequence current component For DAC delta connected main CTs, ratio shall be set for √3 times smaller than the actual ratio of individual phase CTs.
  • Page 117 Section 3 1MRK504116-UUS C IED application CT 300/5 CT 300/5 in Delta (DAC) 20.9 MVA 20.9 MVA 69/12.5 kV 69/12.5 kV YNd1 YNd1 CT 800/5 CT 800/5 en06000554_ansi.vsd ANSI06000554 V1 EN Figure 27: Two differential protection solutions for wye-delta connected power transformer For this particular power transformer the 69 kV side phase-to-ground no-load voltages lead by 30 degrees the 12.5 kV side phase-to- ground no-load voltages.
  • Page 118 Section 3 1MRK504116-UUS C IED application 4. Enter the following settings for all three CT input channels used for the LV side CTs see table 28. Table 28: CT input channels used for the LV side CTs Setting parameter Selected value for both solutions CTprim CTsec CT_WyePoint...
  • Page 119 Section 3 1MRK504116-UUS C IED application Setting parameter Select value for both solution 1 Selected value for both solution 2 (wye connected CT) (delta connected CT) TconfigForW1 TconfigForW2 LocationOLTC1 Not used Not used Other Parameters Not relevant for this application. Not relevant for this application.
  • Page 120 Section 3 1MRK504116-UUS C IED application delta, as shown in the right-hand side in figure 28, it must be ensured that the 24.9 kV currents are rotated by 30° in anti-clockwise direction. Thus, the DAB CT delta connection (see figure 28) must be used for 24.9 kV CTs in order to put 115 kV & 24.9 kV currents in phase.
  • Page 121 Section 3 1MRK504116-UUS C IED application Table 32: General settings of the differential protection Setting parameter selected value for both Solution 1 Selected value for both Solution 2 (wye conected CT) (delta connected CT) RatedVoltageW1 115 kV 115 kV Rated VoltageW2 24.9 kV 24.9 kV RatedCurrentW1...
  • Page 122 Section 3 1MRK504116-UUS C IED application CT 200/1 CT 200/1 in Delta (DAB) 31.5/31.5/(10.5) MVA 31.5/31.5/(10.5) MVA 110±11×1.5% /36.75/(10.5) kV 110±11×1.5% /36.75/(10.5) kV YNyn0(d5) YNyn0(d5) CT 500/5 CT 500/5 in Delta (DAB) en06000558_ansi.vsd ANSI06000558 V1 EN Figure 29: Two differential protection solutions for wye-wye connected transformer. For this particular power transformer the 110 kV side phase-to-ground no-load voltages are exactly in phase with the 36.75 kV side phase-to-ground no-load voltages.
  • Page 123 Section 3 1MRK504116-UUS C IED application Table 33: CT input channels used for the HV side CTs Setting parameter Selected value for both solution 1 Selected value for both Solution 2 (wye connected CTs) (delta connected CTs) CTprim (Equation 32) EQUATION1891 V1 EN CTsec CT_WyePoint...
  • Page 124 Section 3 1MRK504116-UUS C IED application Setting parameter Selected value for both Solution 1 Selected value for both Solution 2 (wye connected) (delta connected) ZSCurrSubtrW1 ZSCurrSubtrW2 TconfigForW1 TconfigForW2 LocationOLT1 Winding 1 (W1) Winding 1 (W1) LowTapPosOLTC1 RatedTapOLTC1 HighTapPsOLTC1 TapHighVoltTC1 StepSizeOLTC1 1.5% 1.5% Other parameters...
  • Page 125 Section 3 1MRK504116-UUS C IED application IEC vector group ANSI designation Positive sequence no-load Required delta CT connection voltage phasor diagram type on wye side of the protected power transformer and internal vector group setting in the IED YNd1 DAC/Yy0 IEC06000559 V1 EN Dyn1 DAB/Yy0...
  • Page 126: Setting Parameters

    Section 3 1MRK504116-UUS C IED application IEC vector group ANSI designation Positive sequence no-load Required delta CT connection voltage phasor diagram type on wye side of the protected power transformer and internal vector group setting in the IED Dyn11 DAC/Yy0 IEC06000562 V1 EN YNd5 YD150...
  • Page 127 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description IdUnre 1.00 - 50.00 0.01 10.00 Unrestrained protection limit, multiple of Winding 1 rated current CrossBlockEn Disabled Enabled Operation Off/On for cross-block logic Enabled between phases NegSeqDiffEn Disabled Enabled Operation Off/On for neg.
  • Page 128 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description ConnectTypeW1 WYE (Y) WYE (Y) Connection type of winding 1: Y-wye or D-delta Delta (D) ConnectTypeW2 WYE (Y) WYE (Y) Connection type of winding 2: Y-wye or D-delta Delta (D) ClockNumberW2 0 [0 deg]...
  • Page 129 Section 3 1MRK504116-UUS C IED application Table 39: T3WPDIF (87T) Group settings (basic) Name Values (Range) Unit Step Default Description Operation Disabled Disabled Operation Disable / Enable Enabled SOTFMode Disabled Enabled Operation mode for switch onto fault feature Enabled tAlarmDelay 0.000 - 60.000 0.001 10.000...
  • Page 130 Section 3 1MRK504116-UUS C IED application Table 41: T3WPDIF (87T) Non group settings (basic) Name Values (Range) Unit Step Default Description RatedVoltageW1 0.05 - 2000.00 0.05 400.00 Rated voltage of transformer winding 1 (HV winding) in kV RatedVoltageW2 0.05 - 2000.00 0.05 231.00 Rated voltage of transformer winding 2 in kV...
  • Page 131: Restricted Earth-Fault Protection, Low Impedance Refpdif (87N)

    Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description CT2RatingW1 1 - 99999 3000 CT primary in A, T-branch 2, on transf. W1 side TconfigForW2 Two CT inputs (T-config.) for winding 2, YES / CT1RatingW2 1 - 99999 3000 CT primary rating in A, T-branch 1, on transf.
  • Page 132: Application

    Section 3 1MRK504116-UUS C IED application Function description IEC 61850 IEC 60617 ANSI/IEEE C37.2 identification identification device number Restricted earth-fault protection, low REFPDIF impedance IdN/I SYMBOL-AA V1 EN 3.5.2.1 Application Breakdown of the insulation between a phase conductor and ground in an effectively or low impedance grounded power system results in a large fault current.
  • Page 133 Section 3 1MRK504116-UUS C IED application Due to its features, REFPDIF (87N) is often used as a main protection of the transformer winding for all faults involving ground. Transformer winding, solidly grounded The most common application is on a solidly grounded transformer winding. The connection is shown in figure 30.
  • Page 134 Section 3 1MRK504116-UUS C IED application ANSI05000211_3_en.vsd ANSI05000211 V3 EN Figure 31: Connection of the low impedance Restricted earth-fault function REFPDIF for a zig-zag grounding transformer Autotransformer winding, solidly grounded Autotransformers can be protected with the low impedance restricted ground fault protection function REFPDIF.
  • Page 135 Section 3 1MRK504116-UUS C IED application ANSI05000212_3_en.vsd ANSI05000212 V3 EN Figure 32: Connection of restricted ground fault, low impedance function REFPDIF (87N) for an autotransformer, solidly grounded Reactor winding, solidly grounded Reactors can be protected with restricted ground fault protection, low impedance function REFPDIF (87N).
  • Page 136 Section 3 1MRK504116-UUS C IED application ANSI05000213_3_en.vsd ANSI05000213 V3 EN Figure 33: Connection of restricted earth-fault, low impedance function REFPDIF (87N) for a solidly grounded reactor Multi-breaker applications Multi-breaker arrangements including ring, one breaker-and-a-half, double breaker and mesh corner arrangements have two sets of current transformers on the phase side. The restricted earth-fault protection, low impedance function REFPDIF (87N) has inputs to allow two current inputs from each side of the transformer.
  • Page 137: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application REFx I3PW1CT1 I3PW1CT2 INd> en05000214_ansi.vsd ANSI05000214 V1 EN Figure 34: Connection of Restricted earth fault, low impedance function REFPDIF (87N) in multi-breaker arrangements CT grounding direction To make the restricted earth-fault protection REFPDIF (87N)operate correctly, the main CTs are always supposed to be wye connected.
  • Page 138 Section 3 1MRK504116-UUS C IED application I3PW1CT2: Phase currents for winding1 second current transformer set for multi- breaker arrangements. When not required configure input to "GRP-OFF". I3PW2CT1: Phase currents for winding 2 first current transformer set. Used for autotransformers. I3PW2CT2: Phase currents for winding 2 second current transformer set for multi- breaker arrangements.
  • Page 139: Setting Parameters

    Section 3 1MRK504116-UUS C IED application IdMin: The setting gives the minimum operation value. The setting is in percent of the IBase value. The neutral current must always be larger than half of this value. A normal setting is 30% of power transformer-winding rated current for the solidly grounded winding.
  • Page 140: 1Ph High Impedance Differential Protection Hzpdif (87)

    Section 3 1MRK504116-UUS C IED application 3.5.3 1Ph High impedance differential protection HZPDIF (87) 3.5.3.1 Identification IEC 61850 IEC 60617 ANSI/IEEE C37.2 Function description identification identification device number 1Ph High impedance differential HZPDIF protection SYMBOL-CC V2 EN 3.5.3.2 Application The 1Ph High impedance differential protection function HZPDIF (87) can be used as: •...
  • Page 141 Section 3 1MRK504116-UUS C IED application 3·87 3·87 ANSI05000738-2-en.vsd ANSI05000738 V2 EN Figure 35: Different applications of a 1Ph High impedance differential protection HZPDIF (87) function The basics of the high impedance principle The high impedance differential protection principle has been used for many years and is well documented.
  • Page 142 Section 3 1MRK504116-UUS C IED application en05000164_ansi.vsd ANSI05000164 V1 EN Figure 36: Example for the high impedance restricted earth fault protection application For a through fault one current transformer might saturate when the other CTs still will feed current. For such a case a voltage will be developed across the stabilising resistor. The calculations are made with the worst situations in mind and a minimum operating voltage V is calculated according to equation...
  • Page 143 Section 3 1MRK504116-UUS C IED application The minimum operating voltage has to be calculated (all loops) and the IED function is set higher than the highest achieved value (setting TripPickup). As the loop resistance is the value to the connection point from each CT, it is advisable to do all the CT core summations in the switchgear to have shortest possible loops.
  • Page 144 Section 3 1MRK504116-UUS C IED application Table 44: 1 A channels: input with minimum operating down to 20 mA Operating Stabilizing Operating Stabilizing Operating Stabilizing Operating TripPi voltage resistor R current level resistor R current level resistor R current level ckup ohms ohms...
  • Page 145 Section 3 1MRK504116-UUS C IED application IED pickup current Ires is the current through the voltage limiter and ΣImag is the sum of the magnetizing currents from all CTs in the circuit (for example, 4 for restricted earth fault protection, 2 for reactor differential protection, 3-5 for autotransformer differential protection).
  • Page 146 Section 3 1MRK504116-UUS C IED application Rres I> Protected Object a) Through load situation b) Through fault situation c) Internal faults ANSI05000427-2-en.vsd ANSI05000427 V2 EN Figure 37: The high impedance principle for one phase with two current transformer inputs Application manual...
  • Page 147: Connection Examples For High Impedance Differential Protection

    Section 3 1MRK504116-UUS C IED application 3.5.3.3 Connection examples for high impedance differential protection WARNING! USE EXTREME CAUTION! Dangerously high voltages might be present on this equipment, especially on the plate with resistors. Do any maintenance ONLY if the primary object protected with this equipment is de-energized.
  • Page 148 Section 3 1MRK504116-UUS C IED application Description Scheme grounding point Note that it is of outmost importance to insure that only one grounding point exist in such scheme. Three-phase plate with setting resistors and metrosils. Necessary connection for three-phase metrosil set. Shown connections are applicable for both types of three-phase plate.
  • Page 149 Section 3 1MRK504116-UUS C IED application AI01 (I) CT 1500/5 Star/Wye AI02 (I) SMAI2 Connected BLOCK AI3P ^GRP2_A AI03 (I) ^GRP2_B ^GRP2_C AI04 (I) ^GRP2_N TYPE AI05 (I) Protected Object AI06 (I) 1-Ph Plate with Metrosil and Resistor ANSI09000170_2_en.vsd ANSI09000170 V2 EN Figure 39: CT connections for restricted earth fault protection Description...
  • Page 150: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application Transformer input module where this current input is located. Note that the CT ratio for high impedance differential protection application must be set as one. • For main CTs with 1A secondary rating the following setting values shall be entered: CTprim 1A and CTsec = 1A CTprim...
  • Page 151 Section 3 1MRK504116-UUS C IED application R series: Set the value of the stabilizing series resistor. Calculate the value according to the examples for each application. Adjust the resistor as close as possible to the calculated example. Measure the value achieved and set this value here. The value shall always be high impedance.
  • Page 152 Section 3 1MRK504116-UUS C IED application It is strongly recommended to use the highest tap of the CT whenever high impedance protection is used. This helps in utilizing maximum CT capability, minimize the current, thereby reducing the stability voltage limit. Another factor is that during internal faults, the voltage developed across the selected tap is limited by the non-linear resistor but in the unused taps, owing to auto-transformer action, voltages may be much higher than design limits might be induced.
  • Page 153 Section 3 1MRK504116-UUS C IED application 2000 ° + × - ° × £ 200 0 3 50 60 approx .100 (Equation 38) EQUATION1887-ANSI V1 EN where 200mA is the current drawn by the IED circuit and 50mA is the current drawn by each CT just at pickup The magnetizing current is taken from the magnetizing curve for the current transformer cores which should be available.
  • Page 154 Section 3 1MRK504116-UUS C IED application 3·87 ANSI05000173-2-en.vsd ANSI05000173 V2 EN Figure 41: Application of the 1Ph High impedance differential protection HZPDIF (87) function on an autotransformer Setting example It is strongly recommended to use the highest tap of the CT whenever high impedance protection is used.
  • Page 155 Section 3 1MRK504116-UUS C IED application Calculation: 1150 > × × (0.3 0.1) 28.75 (Equation 39) EQUATION1760-ANSI V1 EN TripPickup =40 V Select a setting of The current transformer knee point voltage can roughly be calculated from the rated values, considering knee point voltage to be about 70% of the accuracy limit voltage.
  • Page 156 Section 3 1MRK504116-UUS C IED application 3·87 ANSI05000774-3-en.vsd ANSI05000774 V3 EN Figure 42: Application of the high impedance differential function on tertiary busbar Setting example It is strongly recommended to use the highest tap of the CT whenever high impedance protection is used. This helps in utilizing maximum CT capability, minimize the current, thereby reducing the stability voltage limit.
  • Page 157 Section 3 1MRK504116-UUS C IED application Basic data: Cable loop <100 ft AWG10 (one way between the junction point and the farthest resistance: CT) gives loop resistance 2 · 0.05 = 0.1 Ohms Note! Only one way as the system grounding is limiting the ground- fault current.
  • Page 158 Section 3 1MRK504116-UUS C IED application The magnetizing current is taken from the magnetizing curve for the current transformer cores which should be available. The value at TripPickup is taken. Tertiary reactor protection For many transformers there can be a secondary system for local distribution and/or shunt compensation.
  • Page 159 Section 3 1MRK504116-UUS C IED application 3·87 ANSI05000176-2-en.vsd ANSI05000176 V2 EN Figure 43: Application of the1Ph High impedance differential protection HZPDIF (87) function on an autotransformer Setting example It is strongly recommended to use the highest tap of the CT whenever high impedance protection is used.
  • Page 160 Section 3 1MRK504116-UUS C IED application unused taps, owing to auto-transformer action, voltages much higher than design limits might be induced. Basic data: Current transformer ratio: 100/5 A (Note: Must be the same at all locations) CT Class: C200 Secondary resistance: 0.1 Ohms (At 100/5 Tap) Cable loop resistance: <100 ft AWG10 (one way between the junction point and the farthest...
  • Page 161 Section 3 1MRK504116-UUS C IED application Where 200mA is the current drawn by the IED circuit and 50mA is the current drawn by each CT just at pickup. The magnetizing current is taken from the magnetizing curve of the current transformer cores, which should be available. The value at TripPickup is taken.
  • Page 162 Section 3 1MRK504116-UUS C IED application en05000177_ansi.vsd ANSI05000177 V1 EN Figure 44: Application of HZPDIF (87) function as a restricted earth fault IED for an YNd transformer Setting example It is strongly recommended to use the highest tap of the CT whenever high impedance protection is used.
  • Page 163 Section 3 1MRK504116-UUS C IED application Basic data: Transformer rated current on HV winding: 250 A Current transformer ratio: 600-300/5A A (Note: Must be the same at all locations) CT Class: C200 Cable loop resistance: <50 ft AWG10 (one way between the junction point and the farthest CT) to be limited to approx.
  • Page 164 Section 3 1MRK504116-UUS C IED application Alarm level operation The 1Ph High impedance differential protection HZPDIF (87) function has a separate alarm level, which can be used to give alarm for problems with an involved current transformer circuit. The setting level is normally selected to be around 10% of the operating voltage TripPickup.
  • Page 165: Setting Parameters

    Section 3 1MRK504116-UUS C IED application 3.5.3.5 Setting parameters Table 46: HZPDIF (87) Group settings (basic) Name Values (Range) Unit Step Default Description Operation Disabled Disabled Disable/Enable Operation Enabled AlarmPickup 2 - 500 Alarm voltage level on CT secondary tAlarm 0.000 - 60.000 0.001 5.000...
  • Page 166 Section 3 1MRK504116-UUS C IED application stringent demands on the fault clearing equipment in order to maintain an unchanged or increased security level of the power system. The distance protection function in the IED is designed to meet basic requirements for application on transmission and sub-transmission lines (solid grounded systems) although it also can be used on distribution levels.
  • Page 167 Section 3 1MRK504116-UUS C IED application is the zero sequence impedance (Ω/phase) is the fault impedance (Ω), often resistive is the ground-return impedance defined as (Z The voltage on the healthy phases is generally lower than 140% of the nominal phase-to- ground voltage.
  • Page 168 Section 3 1MRK504116-UUS C IED application is setting of the reactive positive sequence reach The magnitude of the ground-fault current in effectively grounded networks is high enough for impedance measuring elements to detect ground faults. However, in the same way as for solidlygrounded networks, distance protection has limited possibilities to detect high resistance faults and should therefore always be complemented with other protection function(s) that can carry out the fault clearance in this case.
  • Page 169 Section 3 1MRK504116-UUS C IED application en05000216_ansi.vsd ANSI05000216 V1 EN Figure 47: High impedance grounded network The operation of high impedance grounded networks is different compared to solid grounded networks where all major faults have to be cleared very fast. In high impedance grounded networks, some system operators do not clear single phase-to- ground faults immediately;...
  • Page 170 Section 3 1MRK504116-UUS C IED application The infeed factor (I can be very high, 10-20 depending on the differences in source impedances at local and remote end. p*ZL (1-p)*ZL en05000217_ansi.vsd ANSI05000217 V1 EN Figure 48: Influence of fault current infeed from remote line end The effect of fault current infeed from remote line end is one of the most driving factors for justify complementary protection to distance protection.
  • Page 171 Section 3 1MRK504116-UUS C IED application The IED has a built in function which shapes the characteristic according to the right figure of figure 49. The load encroachment algorithm will increase the possibility to detect high fault resistances, especially for phase-to-ground faults at remote line end. For example, for a given setting of the load angle LdAngle for Phase selection with load encroachment, quadrilateral characteristic function (FDPSPDIS, 21), the resistive blinder for the zone measurement can be expanded according to the figure...
  • Page 172 Section 3 1MRK504116-UUS C IED application In short line applications, the major concern is to get sufficient fault resistance coverage. Load encroachment is not so common. The line length that can be recognized as a short line is not a fixed length; it depends on system parameters such as voltage and source impedance, see table 47.
  • Page 173 Section 3 1MRK504116-UUS C IED application The IED's ability to set resistive and reactive reach independent for positive and zero sequence fault loops and individual fault resistance settings for phase-to-phase and phase- to-ground fault together with load encroachment algorithm improves the possibility to detect high resistive faults at the same time as the security is improved (risk for unwanted trip due to load encroachment is eliminated), see figure 50.
  • Page 174 Section 3 1MRK504116-UUS C IED application From an application point of view there exists three types of network configurations (classes) that must be considered when making the settings for the protection function. The different network configuration classes are: Parallel line with common positive and zero sequence network Parallel circuits with common positive but isolated zero sequence network Parallel circuits with positive and zero sequence sources isolated.
  • Page 175 Section 3 1MRK504116-UUS C IED application Parallel line in service This type of application is very common and applies to all normal sub-transmission and transmission networks. Let us analyze what happens when a fault occurs on the parallel line see figure 51. From symmetrical components, we can derive the impedance Z at the relay point for normal lines without mutual coupling according to equation 59.
  • Page 176 Section 3 1MRK504116-UUS C IED application IEC09000253_1_en.vsd IEC09000253 V1 EN Figure 52: Equivalent zero sequence impedance circuit of the double-circuit, parallel, operating line with a single phase-to-ground fault at the remote busbar When mutual coupling is introduced, the voltage at the relay point A will be changed according to equation 60.
  • Page 177 Section 3 1MRK504116-UUS C IED application = × × × p Z1 I K 3I (Equation 62) EQUATION1278 V3 EN One can also notice that the following relationship exists between the zero sequence currents: × × I p Z (Equation 63) EQUATION1279 V2 EN Simplification of equation 63, solving it for 3I0p and substitution of the result into equation...
  • Page 178 Section 3 1MRK504116-UUS C IED application OPEN OPEN CLOSED CLOSED en05000222_ansi.vsd ANSI05000222 V1 EN Figure 53: The parallel line is out of service and grounded When the parallel line is out of service and grounded at both line ends on the bus bar side of the line CTs so that zero sequence current can flow on the parallel line, the equivalent zero sequence circuit of the parallel lines will be according to figure 54.
  • Page 179 Section 3 1MRK504116-UUS C IED application æ ö · ç ÷ è ø (Equation 67) DOCUMENT11520-IMG3502 V1 EN æ ö · ç ÷ è ø (Equation 68) DOCUMENT11520-IMG3503 V1 EN Parallel line out of service and not grounded OPEN OPEN CLOSED CLOSED en05000223_ansi.vsd...
  • Page 180 Section 3 1MRK504116-UUS C IED application IEC09000255_1_en.vsd IEC09000255 V1 EN Figure 56: Equivalent zero-sequence impedance circuit for a double-circuit line with one circuit disconnected and not grounded The reduction of the reach is equal to equation 69. × × × ×...
  • Page 181 Section 3 1MRK504116-UUS C IED application Ensure that the underreaching zones from both line ends will overlap a sufficient amount (at least 10%) in the middle of the protected circuit. Tapped line application en05000224_ansi.vsd ANSI05000224 V1 EN Figure 57: Example of tapped line with Auto transformer This application gives rise to similar problem that was highlighted in section "Fault infeed from remote end"...
  • Page 182 Section 3 1MRK504116-UUS C IED application Where: and Z is the line impedance from the A respective C station to the T point. and I is fault current from A respective C station for fault between T and B. V2/V1 Transformation ratio for transformation of impedance at V1 side of the transformer to the measuring side V2 (it is assumed that current and voltage distance function is taken from V2 side of the transformer).
  • Page 183: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application × 28707 L Rarc (Equation 76) EQUATION1456 V1 EN where: represents the length of the arc (in meters). This equation applies for the distance protection zone 1. Consider approximately three times arc foot spacing for the zone 2 and wind speed of approximately 30 m/h is the actual fault current in A.
  • Page 184 Section 3 1MRK504116-UUS C IED application In case of parallel lines, consider the influence of the mutual coupling according to section "Parallel line application with mutual coupling" and select the case(s) that are valid in the particular application. By proper setting it is possible to compensate for the cases when the parallel line is in operation, out of service and not grounded and out of service and grounded in both ends.
  • Page 185 Section 3 1MRK504116-UUS C IED application Z AC Z CB Z CF I A+ IB ANSI05000457-2-en.vsd ANSI05000457 V2 EN Figure 58: Setting of overreaching zone Setting of reverse zone The reverse zone is applicable for purposes of scheme communication logic, current reversal logic, weak-end infeed logic, and so on.
  • Page 186 Section 3 1MRK504116-UUS C IED application Parallel line in service – setting of zone 2 Overreaching zones (in general, zones 2 and 3) must overreach the protected circuit in all cases. The greatest reduction of a reach occurs in cases when both parallel circuits are in service with a single phase-to-ground fault located at the end of a protected line.
  • Page 187 Section 3 1MRK504116-UUS C IED application Set the values of the corresponding zone (zero-sequence resistance and reactance) equal to: æ ö × ç ------------------------- - ÷ è ø (Equation 84) EQUATION561 V1 EN æ ö × ------------------------- - ç – ÷...
  • Page 188 Section 3 1MRK504116-UUS C IED application £ × RFPP 3 X1 (Equation 89) IECEQUATION2306 V1 EN Load impedance limitation, without load encroachment function The following instructions are valid when Phase selection with load encroachment, quadrilateral characteristic function FDPSPDIS (21) is not activated. To deactivate the function, the setting of the load resistance RLdFwd and RldRev in FDPSPDIS (21) must be set to max value (3000).
  • Page 189 Section 3 1MRK504116-UUS C IED application £ × RFPE 0.8 Z load (Equation 92) EQUATION792 V1 EN This equation is applicable only when the loop characteristic angle for the single phase- to-ground faults is more than three times as large as the maximum expected load- impedance angle.
  • Page 190 Section 3 1MRK504116-UUS C IED application Load impedance limitation, with Phase selection with load encroachment, quadrilateral characteristic function activated The parameters for shaping of the load encroachment characteristic are found in the description of Phase selection with load encroachment, quadrilateral characteristic function (FDPSPDIS, 21).
  • Page 191 Section 3 1MRK504116-UUS C IED application × × < < ArgDir L L M ArgNeg (Equation 97) EQUATION1553 V2 EN where: AngDir is the setting for the lower boundary of the forward directional characteristic, by default set to 15 (= -15 degrees) and AngNegRes is the setting for the upper boundary of the forward directional characteristic, by default set to 115 degrees, see figure 59.
  • Page 192 Section 3 1MRK504116-UUS C IED application AngNegRes AngDir en05000722_ansi.vsd ANSI05000722 V1 EN Figure 59: Setting angles for discrimination of forward and reverse fault in Directional impedance quadrilateral function ZDRDIR (21D) The reverse directional characteristic is equal to the forward characteristic rotated by 180 degrees.
  • Page 193: Setting Parameters

    Section 3 1MRK504116-UUS C IED application Setting of timers for distance protection zones The required time delays for different distance protection zones are independent of each other . Distance protection zone 1 can also have a time delay, if so required for selectivity reasons.
  • Page 194 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description 0.000 - 60.000 0.001 0.000 Time delay of trip, Ph-G IMinPUPP 10 - 1000 Minimum pickup delta current (2 x current of lagging phase) for Phase-to-phase loops IMinPUPG 10 - 1000 Minimum pickup phase current for Phase-to-...
  • Page 195: Distance Measuring Zone, Quadrilateral Characteristic For Series Compensated Lines Zmcpdis (21), Zmcapdis (21), Zdsrdir (21D)

    Section 3 1MRK504116-UUS C IED application Table 51: ZDRDIR (21D) Group settings (basic) Name Values (Range) Unit Step Default Description IBase 1 - 99999 3000 Base setting for current level VBase 0.05 - 2000.00 0.05 400.00 Base setting for voltage level IMinPUPP 5 - 30 Minimum pickup delta current (2 x current of...
  • Page 196 Section 3 1MRK504116-UUS C IED application The distance protection function is designed to meet basic requirements for application on transmission and sub transmission lines (solid grounded systems) although it also can be used on distribution levels. System grounding The type of system grounding plays an important roll when designing the protection system.
  • Page 197 Section 3 1MRK504116-UUS C IED application The voltage on the healthy phases is generally lower than 140% of the nominal phase-to- ground voltage. This corresponds to about 80% of the nominal phase-to-phase voltage. The high zero sequence current in solid grounded networks makes it possible to use impedance measuring technique to detect ground-fault.
  • Page 198 Section 3 1MRK504116-UUS C IED application occurs on the protected line. The fault infeed may enlarge the fault impedance seen by the distance protection. This effect is very important to keep in mind when both planning the protection system and making the settings. With reference to figure 61, we can draw the equation for the bus voltage Va at left side as: ×...
  • Page 199 Section 3 1MRK504116-UUS C IED application impedance. This has the drawback that it will reduce the sensitivity of the protection that is, the ability to detect resistive faults. The IED has a built in function which shapes the characteristic according to the right figure 62.
  • Page 200 Section 3 1MRK504116-UUS C IED application Table 52: Definition of long lines Line category 110 kV 500 kV Long lines 45-60 miles 200-250 miles Very long lines >60 miles >250 miles The possibility in IED to set resistive and reactive reach independent for positive and zero sequence fault loops and individual fault resistance settings for phase-to-phase and phase-to-ground fault together with load encroachment algorithm improves the possibility to detect high resistive faults at the same time as the security is improved...
  • Page 201 Section 3 1MRK504116-UUS C IED application Parallel lines introduce an error in the measurement due to the mutual coupling between the parallel lines. The lines need not be of the same voltage to experience mutual coupling, and some coupling exists even for lines that are separated by 100 meters or more.
  • Page 202 Section 3 1MRK504116-UUS C IED application Parallel line applications This type of networks are defined as those networks where the parallel transmission lines terminate at common nodes at both ends. We consider the three most common operation modes: • parallel line in service •...
  • Page 203 Section 3 1MRK504116-UUS C IED application FAULT en05000221_ansi.vsd ANSI05000221 V1 EN Figure 64: Class 1, parallel line in service The equivalent circuit of the lines can be simplified, as shown in figure 65. Z0 m 99000038.vsd IEC99000038 V1 EN Figure 65: Equivalent zero sequence impedance circuit of the double-circuit, parallel, operating line with a single phase-to-ground-fault at the remote busbar...
  • Page 204 Section 3 1MRK504116-UUS C IED application Where: = Z0m/(3 · Z1L) The second part in the parentheses is the error introduced to the measurement of the line impedance. If the current on the parallel line has negative sign compared to the current on the protected line that is, the current on the parallel line has an opposite direction compared to the current on the protected line, the distance function overreaches.
  • Page 205 Section 3 1MRK504116-UUS C IED application Calculation for a 400 kV line, where we for simplicity have excluded the resistance, gives with X1L=0.48 Ohm/Mile, X0L=1.4Ohms/Mile, zone 1 reach is set to 90% of the line reactance p=71% that is, the protection is underreaching with approximately 20%. The zero-sequence mutual coupling can reduce the reach of distance protection on the protected circuit when the parallel line is in normal operation.
  • Page 206 Section 3 1MRK504116-UUS C IED application (Equation 111) EQUATION2002 V4 EN The influence on the distance measurement can be a considerable overreach, which must be considered when calculating the settings. It is recommended to use a separate setting group for this operation condition, since it reduces the reach considerably when the line is in operation.
  • Page 207 Section 3 1MRK504116-UUS C IED application practice, the equivalent zero sequence impedance circuit for faults at the remote bus bar can be simplified to the circuit shown in figure 68. The line zero-sequence mutual impedance does not influence the measurement of the distance protection in a faulty circuit.
  • Page 208 Section 3 1MRK504116-UUS C IED application × é ù é ù ë û ë û (Equation 117) EQUATION1287 V2 EN The imaginary component of the same factor is equal to equation 118. × é ù é ù ë û ë û...
  • Page 209 Section 3 1MRK504116-UUS C IED application This application gives rise to similar problem that was highlighted in section "Fault infeed from remote end" that is, increased measured impedance due to fault current infeed. For example, for faults between the T point and B station the measured impedance at A and C is as follows: ·Z (Equation 119)
  • Page 210 Section 3 1MRK504116-UUS C IED application Fault resistance The performance of distance protection for single phase-to-ground faults is very important, because normally more than 70% of the faults on transmission lines are single phase-to-ground faults. At these faults, the fault resistance is composed of three parts: arc resistance, resistance of a tower construction, and tower-footing resistance.
  • Page 211 Section 3 1MRK504116-UUS C IED application Steady state voltage regulation and increase of voltage collapse limit A series capacitor is capable of compensating the voltage drop of the series inductance in a transmission line, as shown in figure 71. During low loading, the system voltage drop is lower and at the same time, the voltage drop on the series capacitor is lower.
  • Page 212 Section 3 1MRK504116-UUS C IED application limit 1000 1200 1400 1600 1800 P[MW] en06000586_ansi.vsd ANSI06000586 V1 EN Figure 72: Voltage profile for a simple radial power line with 0, 30, 50 and 70% of compensation Increased power transfer capability by raising the first swing stability limit Consider the simple one-machine and infinite bus system shown in figure 73.
  • Page 213 Section 3 1MRK504116-UUS C IED application without SC with SC Mech Mech en06000588.vsd IEC06000588 V1 EN Figure 74: Equal area criterion and first swing stability without and with series compensation This means that the system is stable if A ≤ (A ).
  • Page 214 Section 3 1MRK504116-UUS C IED application (Mvar) (S.C.) Capacitive Power flow (MW) 1000 1500 (T.L. + S.C.) Inductive Transmission 500 kV (T.L.) 500 km Line Series 1000 Compensation k = 50 % en06000589.vsd IEC06000589 V1 EN Figure 75: Self-regulating effect of reactive power balance Increase in power transfer The increase in power transfer capability as a function of the degree of compensation for a transmission line can be explained by studying the circuit shown in figure 76.
  • Page 215 Section 3 1MRK504116-UUS C IED application The effect on the power transfer when considering a constant angle difference (δ) between the line ends is illustrated in figure 77. Practical compensation degree runs from 20 to 70 percent. Transmission capability increases of more than two times can be obtained in practice.
  • Page 216 Section 3 1MRK504116-UUS C IED application (Equation 125) EQUATION1899 V1 EN Reduced costs of power transmission due to decreased investment costs for new power line As shown in figure the line loading can easily be increased 1.5-2 times by series compensation.
  • Page 217 Section 3 1MRK504116-UUS C IED application en06000595.vsd IEC06000595 V1 EN Figure 80: Thyristor switched series capacitor en06000596_ansi.vsd ANSI06000596 V1 EN Figure 81: Thyristor controlled series capacitor Line current Current through the thyristor Voltage over the series capacitor Rated reactance of the series capacitor A thyristor controlled series capacitor (TCSC) allows continuous control of the series capacitor reactance.
  • Page 218 Section 3 1MRK504116-UUS C IED application 0.02 0.02 0.04 0.04 0.06 0.06 0.08 0.08 0.12 0.12 0.14 0.14 0.16 0.16 0.18 0.18 0.02 0.02 0.04 0.04 0.06 0.06 0.08 0.08 0.12 0.12 0.14 0.14 0.16 0.16 0.18 0.18 0.02 0.02 0.04 0.04 0.06...
  • Page 219 Section 3 1MRK504116-UUS C IED application Imperatriz TCSC, Operating range Continuous 30 min Continuous 30 min. overload 10s overload -0.2 Bypass mode -0.4 Series5 1200 1500 1800 2100 2400 2700 3000 Line current (Arms) en06000598.vsd IEC06000598 V1 EN Figure 83: Operating range of a TCSC installed for damping of power oscillations (example) During continuous valve bypass the TCSC represents an inductive impedance of about...
  • Page 220 Section 3 1MRK504116-UUS C IED application Voltage and current inversion Series capacitors influence the magnitude and the direction of fault currents in series compensated networks. They consequently influence phase angles of voltages measured in different points of series compensated networks and this performances of different protection functions, which have their operation based on properties of measured voltage and current phasors.
  • Page 221 Section 3 1MRK504116-UUS C IED application With bypassed With inserted capacitor capacitor Source voltage Pre -fault voltage V’ Fault voltage Source en06000605_ansi.vsd ANSI06000605 V1 EN Figure 84: Voltage inversion on series compensated line With bypassed With inserted capacitor capacitor en06000606_ansi.vsd ANSI06000606 V1 EN Figure 85: Phasor diagrams of currents and voltages for the bypassed and...
  • Page 222 Section 3 1MRK504116-UUS C IED application The IED point voltage inverses its direction due to presence of series capacitor and its dimension. It is a common practice to call this phenomenon voltage inversion. Its consequences on operation of different protections in series compensated networks depend on their operating principle.
  • Page 223 Section 3 1MRK504116-UUS C IED application The first case corresponds also to conditions on non compensated lines and in cases, when the capacitor is bypassed either by spark gap or by the bypass switch, as shown in phasor diagram in figure 87. The resultant reactance is in this case of inductive nature and the fault currents lags source voltage by 90 electrical degrees.
  • Page 224 Section 3 1MRK504116-UUS C IED application based on residual (zero sequence) and negative sequence currents should be considered in studies as well. Current inversion in zero sequence systems with low zero sequence source impedance (a number of power transformers connected in parallel) must be considered as practical possibility in many modern networks.
  • Page 225 Section 3 1MRK504116-UUS C IED application é ù - × × × + - × × ê ú ë û × æ ö × ç ÷ è ø (Equation 132) EQUATION1906 V1 EN The line fault current consists of two components: •...
  • Page 226 Section 3 1MRK504116-UUS C IED application × × + - × × × × × - × æ ö × ç ÷ × è ø × é × × ù × × × ê ú ê ú ê ú × ×...
  • Page 227 Section 3 1MRK504116-UUS C IED application 0.02 0.04 0.06 0.08 0.12 0.14 0.16 0.18 t[ms ] en06000610.vsd IEC06000610 V1 EN Figure 89: Short circuit currents for the fault at the end of 500 km long 500 kV line without and with SC Location of instrument transformers Location of instrument transformers relative to the line end series capacitors plays an important role regarding the dependability and security of a complete protection...
  • Page 228 Section 3 1MRK504116-UUS C IED application CT1 and VT1 on figure represent the case with bus side instrument transformers. The protection devices are in this case exposed to possible voltage and current inversion for line faults, which decreases the required dependability. In addition to this may series capacitor cause negative apparent impedance to distance IEDs on protected and adjacent lines as well for close-in line faults (see also figure LOC=0%), which...
  • Page 229 Section 3 1MRK504116-UUS C IED application Distance IED near the feeding bus will see in different cases fault on remote end bus depending on type of overvoltage protection used on capacitor bank (spark gap or MOV) and SC location on protected power line. 100 % 50 % 33 %...
  • Page 230 Section 3 1MRK504116-UUS C IED application MOV protected series capacitor Line current as a function of time Capacitor voltage as a function of time Capacitor current as a function of time MOV current as a function of time en06000614_ansi.vsd ANSI06000614 V1 EN Figure 93: MOV protected capacitor with examples of capacitor voltage and corresponding currents...
  • Page 231 Section 3 1MRK504116-UUS C IED application Extensive studies at Bonneville Power Administration in USA ( ref. Goldsworthy, D,L “A Linearized Model for MOV-Protected series capacitors” Paper 86SM357–8 IEEE/ PES summer meeting in Mexico City July 1986) have resulted in construction of a non- linear equivalent circuit with series connected capacitor and resistor.
  • Page 232 Section 3 1MRK504116-UUS C IED application • Series capacitor becomes nearly completely bridged by MOV when the line current becomes higher than 10-times the protective current level (I £ 10· k · I Impact of series compensation on protective IED of adjacent lines Voltage inversion is not characteristic for the buses and IED points closest to the series compensated line only.
  • Page 233 Section 3 1MRK504116-UUS C IED application equation indicates the deepness of the network to which it will feel the influence of series compensation through the effect of voltage inversion. It is also obvious that the position of series capacitor on compensated line influences in great extent the deepness of voltage inversion in adjacent system.
  • Page 234 Section 3 1MRK504116-UUS C IED application may help eliminating the basic reason for wrong measurement. The most known of them are decrease of the reach due to presence of series capacitor, which apparently decreases the line reactance, and introduction of permanent memory voltage in directional measurement.
  • Page 235 Section 3 1MRK504116-UUS C IED application Equation is applicable for the case when the VTs are located on the bus side of series capacitor. It is possible to remove X from the equation in cases of VTs installed in line side, but it is still necessary to consider the safety factor K If the capacitor is out of service or bypassed, the reach with these settings can be less than 50% of protected line dependent on compensation degree and there will be a section, G in figure 96, of the power line where no tripping occurs from either end.
  • Page 236 Section 3 1MRK504116-UUS C IED application < < (Equation 141) EQUATION1898 V1 EN and in figure a three phase fault occurs beyond the capacitor. The resultant IED impedance seen from the D IED location to the fault may become negative (voltage inversion) until the spark gap has flashed.
  • Page 237 Section 3 1MRK504116-UUS C IED application en06000621_ansi.vsd ANSI06000621 V1 EN Figure 99: Distance IED on adjacent power lines are influenced by the negative impedance Normally the first zone of this protection must be delayed until the gap flashing has taken place. If the delay is not acceptable, some directional comparison must also be added to the protection of all adjacent power lines.
  • Page 238 Section 3 1MRK504116-UUS C IED application ordinary fault. However, a good protection system should be able to operate correctly before and after gap flashing occurs. en06000584_small.vsd en06000625.vsd IEC06000584-SMALL V1 EN IEC06000625 V1 EN Figure 101: Quadrilateral Figure 100: Cross-polarized characteristic with quadrilateral separate impedance characteristic...
  • Page 239 Section 3 1MRK504116-UUS C IED application in figure and a fault occurs behind the capacitor, the resultant reactance becomes negative and the fault current will have an opposite direction compared with fault current in a power line without a capacitor (current inversion). The negative direction of the fault current will persist until the spark gap has flashed.
  • Page 240 Section 3 1MRK504116-UUS C IED application Series compensation additionally exaggerates the effect of zero sequence mutual impedance between two circuits, see figure 103. It presents a zero sequence equivalent circuit for a fault at B bus of a double circuit line with one circuit disconnected and grounded at both IEDs.
  • Page 241: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application protection on healthy circuit and this way endangers even more the complete system stability. To avoid the unwanted tripping, some manufacturers provide a feature in their distance protection which detects that the fault current has changed in direction and temporarily blocks distance protection.
  • Page 242 Section 3 1MRK504116-UUS C IED application • The phase impedance of non transposed lines is not identical for all fault loops. The difference between the impedances for different phase-to-ground loops can be as large as 5-10% of the total line impedance. •...
  • Page 243 Section 3 1MRK504116-UUS C IED application æ ö × × ç ÷ è ø (Equation 150) EQUATION302 V3 EN Z AC Z CB Z CF I A+ IB ANSI05000457-2-en.vsd ANSI05000457 V2 EN Figure 105: Setting of reverse zone The reverse zone is applicable for purposes of scheme communication logic, current reversal logic, weak-end-infeed logic, and so on.
  • Page 244 Section 3 1MRK504116-UUS C IED application Directional control The directional function (ZDSRDIR) which is able to cope with the condition at voltage reversal, shall be used in all IEDs with conventional distance protection (ZMCPDIS,ZMCAPDIS, 21). This function is necessary in the protection on compensated lines as well as all non-compensated lines connected to this busbar (adjacent lines).
  • Page 245 Section 3 1MRK504116-UUS C IED application 100 % 99000202.vsd IEC99000202 V1 EN Figure 106: Reduced reach due to the expected sub-harmonic oscillations at different degrees of compensation æ ö c degree of compensation ç ÷ ç ÷ è ø (Equation 152) EQUATION1894 V1 EN is the reactance of the series capacitor p is the maximum allowable reach for an under-reaching zone with respect to the sub-...
  • Page 246 Section 3 1MRK504116-UUS C IED application Reactive Reach Compensated lines with the capacitor into the zone 1 reach : LLOC en07000063.vsd IEC07000063 V1 EN Figure 107: Simplified single line diagram of series capacitor located at X LLOC from A station Application manual...
  • Page 247 Section 3 1MRK504116-UUS C IED application en06000584.vsd IEC06000584 V1 EN Figure 108: Measured impedance at voltage inversion Forward direction: Where equals line reactance up to the series capacitor(in the picture LLoc approximate 33% of XLine) is set to (XLindex-XC) · p/100. is defined according to figure is safety factor for fast operation of Zone 1 Compensated line with the series...
  • Page 248 Section 3 1MRK504116-UUS C IED application When the calculation of XFw gives a negative value the zone 1 must be permanently blocked. For protection on non compensated lines facing series capacitor on next line. The setting is thus: • X1 is set to (XLine-XC · K) · p/100. •...
  • Page 249 Section 3 1MRK504116-UUS C IED application The increased reach related to the one used in non compensated system is recommended for all protections in the vicinity of series capacitors to compensate for delay in the operation caused by the sub harmonic swinging. Settings of the resistive reaches are limited according to the minimum load impedance.
  • Page 250 Section 3 1MRK504116-UUS C IED application Check the reduction of a reach for the overreaching zones due to the effect of the zero sequence mutual coupling. The reach is reduced for a factor: × (Equation 155) EQUATION1426 V1 EN If the denominator in equation is called B and Z0m is simplified to X0m, then the real and imaginary part of the reach reduction factor for the overreaching zones can be written as:...
  • Page 251 Section 3 1MRK504116-UUS C IED application The final reach in resistive direction for phase-to-ground fault loop measurement automatically follows the values of the line-positive and zero-sequence resistance, and at the end of the protected zone is equal to equation 160. ×...
  • Page 252 Section 3 1MRK504116-UUS C IED application The load impedance [Ω/phase] is a function of the minimum operation voltage and the maximum load current: loa d × ma x (Equation 165) EQUATION1719 V1 EN Minimum voltage Vmin and maximum current Imax are related to the same operating conditions.
  • Page 253 Section 3 1MRK504116-UUS C IED application £ × RFPP 1.6 Z load (Equation 168) EQUATION579 V2 EN Equation is applicable only when the loop characteristic angle for the phase-to- phase faults is more than three times as large as the maximum expected load- impedance angle.
  • Page 254: Setting Parameters

    Section 3 1MRK504116-UUS C IED application Setting of timers for distance protection zones The required time delays for different distance-protection zones are independent of each other. Distance protection zone1 can also have a time delay, if so required for selectivity reasons. One can set the time delays for all zones (basic and optional) in a range of 0 to 60 seconds.
  • Page 255 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description R1PG 0.01 - 1000.00 ohm/p 0.01 5.00 Positive seq. resistance for characteristic angle, Ph-G X0PG 0.10 - 9000.00 ohm/p 0.01 100.00 Zero sequence reactance reach, Ph-G R0PG 0.01 - 3000.00 ohm/p 0.01...
  • Page 256 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description OperationPG Disabled Enabled Operation mode Disable/Enable of Phase- Enabled Ground loops X1FwPG 0.10 - 3000.00 ohm/p 0.01 30.00 Positive sequence reactance reach, Ph-G, forward R1PG 0.01 - 1000.00 ohm/p 0.01 5.00...
  • Page 257: Phase Selection, Quadrilateral Characteristic With Fixed Angle

    Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description RLdFwd 1.00 - 3000.00 ohm/p 0.01 80.00 Forward resistive reach for the load impedance area RldRev 1.00 - 3000.00 ohm/p 0.01 80.00 Reverse resistive reach for the load impedance area LdAngle 5 - 70...
  • Page 258: Application

    Section 3 1MRK504116-UUS C IED application 3.6.3.2 Application The operation of transmission networks today is in many cases close to the stability limit. The ability to accurately and reliably classify the different types of fault, so that single pole tripping and autoreclosing can be used plays an important role in this matter.
  • Page 259 Section 3 1MRK504116-UUS C IED application RFltRevPP and RFltRevPP for phase-to-phase faults have to be increased to avoid that FDPSPDIS (21) characteristic shall cut off some part of the zone characteristic. The necessary increased setting of the fault resistance coverage can be derived from trigonometric evaluation of the basic characteristic for respectively fault type.
  • Page 260 Section 3 1MRK504116-UUS C IED application ( / loop) 60° 60° ( / loop) IEC09000043_1_en.vsd IEC09000043 V1 EN Figure 109: Relation between distance protection ZMQPDIS (21) and FDPSPDIS (21) for phase-to-ground fault φloop>60° (setting parameters in italic) 1 FDPSPDIS (21) (red line) 2 ZMQPDIS(21) RFltRevPG +XN)/tan(60°)
  • Page 261 Section 3 1MRK504116-UUS C IED application The reactive reach in forward direction must as minimum be set to cover the measuring zone used in the Teleprotection schemes, mostly zone 2. Equation equation gives the minimum recommended reactive reach. ³ × 1.44 X1 (Equation 171) EQUATION1309 V1 EN...
  • Page 262 Section 3 1MRK504116-UUS C IED application The resistive reach in reverse direction must be set longer than the longest reverse zones. In blocking schemes it must be set longer than the overreaching zone at remote end that is used in the communication scheme. In equation the index ZmRv references the specific zone to be coordinated to.
  • Page 263 Section 3 1MRK504116-UUS C IED application ( / phase) 60° 60° ( / phase) IEC09000257_1_en.vsd IEC09000257 V1 EN Figure 110: Relation between distance protection (ZMQPDIS) (21) and FDPSPDIS (21) characteristic for phase-to-phase fault for φline>60° (setting parameters in italic) 1 FDPSPDIS (21)(red line) 2 ZMQPDIS(21) RFltRevPP 3 0.5 ·...
  • Page 264 Section 3 1MRK504116-UUS C IED application Resistive reach with load encroachment characteristic The procedure for calculating the settings for the load encroachment consist basically to define the load angle LdAngle, the blinder RLdFwd in forward direction and blinder RLdRev in reverse direction, as shown in figure 111. RLdFwd LdAngle LdAngle...
  • Page 265: Setting Parameters

    Section 3 1MRK504116-UUS C IED application The resistive boundary RLdRev for load encroachment characteristic in reverse direction can be calculated in the same way as RLdFwd, but use maximum importing power that might occur instead of maximum exporting power and the relevant Vmin voltage for this condition.
  • Page 266: Full-Scheme Distance Measuring, Mho Characteristic Zmhpdis (21)

    Section 3 1MRK504116-UUS C IED application Table 57: FDPSPDIS (21) Group settings (advanced) Name Values (Range) Unit Step Default Description OperationZ< Disabled Enabled Operation of impedance based measurement Enabled OperationI> Disabled Disabled Operation of current based measurement Enabled IPh> 10 - 2500 Start value for phase over-current element Pickup_N 10 - 2500...
  • Page 267 Section 3 1MRK504116-UUS C IED application System grounding The type of system grounding plays an important role when designing the protection system. In the following some hints with respect to distance protection are highlighted. Solid grounded networks In solid grounded systems the transformer neutrals are connected solidly to ground without any impedance between the transformer neutral and ground.
  • Page 268 Section 3 1MRK504116-UUS C IED application The high zero-sequence current in solid grounded networks makes it possible to use impedance measuring technique to detect ground fault. However, distance protection has limited possibilities to detect high resistance faults and should therefore always be complemented with other protection function(s) that can carry out the fault clearance in those cases.
  • Page 269 Section 3 1MRK504116-UUS C IED application What is typical for this type of network is that the magnitude of the ground-fault current is very low compared to the short-circuit current. The voltage on the healthy phases will get a magnitude of √3 times the phase voltage during the fault. The zero- sequence voltage (3V0) will have the same magnitude in different places in the network due to low voltage drop distribution.
  • Page 270 Section 3 1MRK504116-UUS C IED application of cross-country faults, many network operators want to selectively clear one of the two ground faults. To handle this type phenomena Phase preference logic function (PPLPHIZ) is needed, which is not common to be used in transmission applications. In this type of network, it is mostly not possible to use distance protection for detection and clearance of ground faults.
  • Page 271 Section 3 1MRK504116-UUS C IED application Load encroachment In some cases the load impedance might enter the zone characteristic without any fault on the protected line. The phenomenon is called load encroachment and it might occur when an external fault is cleared and high emergency load is transferred on the protected line.
  • Page 272 Section 3 1MRK504116-UUS C IED application LdAngle LdAngle LdAngle LdAngle en06000404_ansi.vsd ANSI06000404 V1 EN Figure 116: Load encroachment of Faulty phase identification with load encroachment for mho function FMPSPDIS (21) characteristic The use of the load encroachment feature is essential for long heavy loaded lines, where there might be a conflict between the necessary emergency load transfer and necessary sensitivity of the distance protection.
  • Page 273 Section 3 1MRK504116-UUS C IED application In short line applications, the major concern is to get sufficient fault resistance coverage. Load encroachment is not so common. The line length that can be recognized as a short line is not a fixed length; it depends on system parameters such as voltage and source impedance, see table 47.
  • Page 274 Section 3 1MRK504116-UUS C IED application blinder might cut off a larger part of the operating area of the circle (see to the right of figure 115). It is recommended to use at least one of the load discrimination functions for long heavy loaded transmission lines.
  • Page 275 Section 3 1MRK504116-UUS C IED application • The possibility of different setting values that influence the ground-return compensation for different distance zones within the same group of setting parameters. • Different groups of setting parameters for different operating conditions of a protected multi circuit line.
  • Page 276 Section 3 1MRK504116-UUS C IED application Z0 m 99000038.vsd IEC99000038 V1 EN Figure 118: Equivalent zero sequence impedance circuit of the double-circuit, parallel, operating line with a single phase-to-ground fault at the remote busbar. If the current on the parallel line have negative sign compared to the current on the protected line, that is, the current on the parallel line has an opposite direction compare to the current on the protected line, the distance function will overreach.
  • Page 277 Section 3 1MRK504116-UUS C IED application When the parallel line is out of service and grounded at both ends on the bus bar side of the line CT so that zero sequence current can flow on the parallel line, the equivalent zero sequence circuit of the parallel lines will be according to figure 119.
  • Page 278 Section 3 1MRK504116-UUS C IED application When the parallel line is out of service and not grounded, the zero sequence on that line can only flow through the line admittance to the ground. The line admittance is high which limits the zero sequence current on the parallel line to very low values. In practice, the equivalent zero sequence impedance circuit for faults at the remote bus bar can be simplified to the circuit shown in figure The line zero sequence mutual impedance does not influence the measurement of the...
  • Page 279 Section 3 1MRK504116-UUS C IED application ANSI09000160-1-en.vsd ANSI09000160 V1 EN Figure 123: Example of tapped line with Auto transformer This application gives rise to similar problem that was highlighted in section "Fault infeed from remote end", that is, increased measured impedance due to fault current infeed.
  • Page 280: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application For this example with a fault between T and B, the measured impedance from the T point to the fault will be increased by a factor defined as the sum of the currents from T point to the fault divided by the IED current.
  • Page 281 Section 3 1MRK504116-UUS C IED application The setting values of all parameters that belong to ZMHPDIS must correspond to the parameters of the protected line and be coordinated to the selectivity plan for the network. Use different setting groups for the cases when the parallel line is in operation, out of service and not grounded and out of service and grounded in both ends.
  • Page 282 Section 3 1MRK504116-UUS C IED application • The impedance corresponding to the protected line, plus the first zone reach of the shortest adjacent line. • The impedance corresponding to the protected line, plus the impedance of the maximum number of transformers operating in parallel on the bus at the remote end of the protected line.
  • Page 283 Section 3 1MRK504116-UUS C IED application Consider the possible enlarging factor that might exist due to fault infeed from adjacent lines. Equation can be used to calculate the reach in reverse direction when the zone is used for blocking scheme, weak-end infeed, and so on. ³...
  • Page 284 Section 3 1MRK504116-UUS C IED application × (Equation 193) EQUATION1426 V1 EN If needed, enlarge the zone reach due to the reduction by mutual coupling. Consider also the influence on the zone reach due to fault current infeed from adjacent lines. Parallel line is out of service and grounded in both ends Apply the same measures as in the case with a single set of setting parameters.
  • Page 285 Section 3 1MRK504116-UUS C IED application To avoid load encroachment for the phase-to-ground measuring elements, the set impedance reach of any distance protection zone must be less than 80% of the minimum load impedance. For setting of the ground-fault loop, the following formula can be used: £...
  • Page 286 Section 3 1MRK504116-UUS C IED application The maximum setting for phase-to-phase fault can be defined by trigonometric analyze of the same figure 125. The formula to avoid load encroachment for the phase-to-phase measuring elements will thus be according to equation 197. £...
  • Page 287: Setting Parameters

    Section 3 1MRK504116-UUS C IED application Setting of direction for offset mho If offset mho has been selected, one can select if the offset mho shall be Non- Directional, Forward or Reverse by setting the parameter OfffsetMhoDir. When forward or reverse operation is selected, then the operation characteristic will be cut off by the directional lines used for the mho characteristic.
  • Page 288 Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description ZAngPG 10 - 90 Angle for positive sequence line impedance for Phase-Ground loop 0.00 - 3.00 0.01 0.80 Magnitud of ground return compensation factor KN KNAng -180 - 180 Angle for ground return compensation factor ZRevPG 0.005 - 3000.000...
  • Page 289: Full-Scheme Distance Protection, Quadrilateral For Earth Faults Zmmpdis (21), Zmmapdis (21)

    Section 3 1MRK504116-UUS C IED application 3.6.5 Full-scheme distance protection, quadrilateral for earth faults ZMMPDIS (21), ZMMAPDIS (21) Function description IEC 61850 IEC 60617 ANSI/IEEE C37.2 identification identification device number Fullscheme distance protection, ZMMPDIS quadrilateral for earth faults (zone 1) S00346 V1 EN Fullscheme distance protection, ZMMAPDIS...
  • Page 290 Section 3 1MRK504116-UUS C IED application xx05000215_ansi.vsd ANSI05000215 V1 EN Figure 126: Solidly grounded network The ground fault current is as high or even higher than the short-circuit current. The series impedances determine the magnitude of the ground fault current. The shunt admittance has very limited influence on the ground fault current.
  • Page 291 Section 3 1MRK504116-UUS C IED application Effectively grounded networks A network is defined as effectively grounded if the ground fault factor fe is less than 1.4. The ground fault factor is defined according to equation 52. (Equation 199) ANSIEQUATION1268 V1 EN Where: is the highest fundamental frequency voltage on one of the healthy phases at single phase- to-ground fault.
  • Page 292 Section 3 1MRK504116-UUS C IED application voltage (3U0) will have the same magnitude in different places in the network due to low voltage drop distribution. The magnitude of the total fault current can be calculated according to the formula below: (Equation 202) EQUATION1271 V3 EN Where:...
  • Page 293 Section 3 1MRK504116-UUS C IED application preference logic (PPLPHIZ) is needed, which is not common to be used in transmission applications. In this type of network, it is mostly not possible to use distance protection for detection and clearance of ground-faults. The low magnitude of the ground-fault current might not give start of the zero sequence measurement element or the sensitivity will be too low for acceptance.
  • Page 294 Section 3 1MRK504116-UUS C IED application The effect of fault current infeed from remote end is one of the most driving factors for justify complementary protection to distance protection. Load encroachment In some cases the load impedance might enter the zone characteristic without any fault on the protected line.
  • Page 295 Section 3 1MRK504116-UUS C IED application Load impedance area in LdAngle forward direction LdAngle LdAngle LdAngle RLdFwd RldRev ANSI05000495_2_en.vsd ANSI05000495 V2 EN Figure 129: Load encroachment phenomena and shaped load encroachment characteristic Short line application In short line applications, the major concern is to get sufficient fault resistance coverage.
  • Page 296 Section 3 1MRK504116-UUS C IED application Long transmission line application For long transmission lines the margin to the load impedance that is, to avoid load encroachment, will normally be a major concern. It is difficult to achieve high sensitivity for phase-to-ground fault at remote end of a long lines when the line is heavy loaded.
  • Page 297 Section 3 1MRK504116-UUS C IED application One example of class3 networks could be the mutual coupling between a 400 kV line and rail road overhead lines. This type of mutual coupling is not so common although it exists and is not treated any further in this manual. For each type of network class we can have three different topologies;...
  • Page 298 Section 3 1MRK504116-UUS C IED application × 3I K × × (Equation 206) EQUATION1275 V2 EN Where: is phase-to-ground voltage at the IED point is phase current in the faulty phase is ground to fault current is positive sequence impedance is zero sequence impedance Z<...
  • Page 299 Section 3 1MRK504116-UUS C IED application If the current on the parallel line have negative sign compare to the current on the protected line that is, the current on the parallel line has an opposite direction compare to the current on the protected line, the distance function will overreach. If the currents have the same direction, the distance protection will underreach.
  • Page 300 Section 3 1MRK504116-UUS C IED application Here the equivalent zero sequence impedance is equal to Z0-Z0m in parallel with (Z0- Z0m)/Z0-Z0m+Z0m which is equal to equation 207. (Equation 207) EQUATION2002 V4 EN The influence on the distance measurement will be a considerable overreach, which must be considered when calculating the settings.
  • Page 301 Section 3 1MRK504116-UUS C IED application high which limits the zero sequence current on the parallel line to very low values. In practice, the equivalent zero sequence impedance circuit for faults at the remote bus bar can be simplified to the circuit shown in figure The line zero-sequence mutual impedance does not influence the measurement of the distance protection in a faulty circuit.
  • Page 302 Section 3 1MRK504116-UUS C IED application × é ù é ù ë û ë û (Equation 213) EQUATION1287 V2 EN The imaginary component of the same factor is equal to equation 214. × é ù é ù ë û ë û...
  • Page 303 Section 3 1MRK504116-UUS C IED application infeed. For example for faults between the T point and B station the measured impedance at A and C will be ·Z (Equation 215) DOCUMENT11524-IMG3509 V2 EN æ ö æ ö × × ç ÷...
  • Page 304: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application Fault resistance The performance of distance protection for single phase-to-ground faults is very important, because normally more than 70% of the faults on transmission lines are single phase-to-ground faults. At these faults, the fault resistance is composed of three parts: arc resistance, resistance of a tower construction, and tower-footing resistance.
  • Page 305 Section 3 1MRK504116-UUS C IED application • The phase impedance of non transposed lines is not identical for all fault loops. The difference between the impedances for different phase-to-ground loops can be as large as 5-10% of the total line impedance. •...
  • Page 306 Section 3 1MRK504116-UUS C IED application æ ö × × ç ÷ è ø (Equation 218) EQUATION302 V3 EN Z AC Z CB Z CF I A+ IB ANSI05000457-2-en.vsd ANSI05000457 V2 EN Figure 137: Setting of reverse zone The reverse zone is applicable for purposes of scheme communication logic, current reversal logic, weak-end-infeed logic, and so on.
  • Page 307 Section 3 1MRK504116-UUS C IED application Parallel line in service – Setting of zone1 With reference to section "Parallel line applications", the zone reach can be set to 85% of protected line. Parallel line in service – setting of zone2 Overreaching zones (in general, zones 2 and 3) must overreach the protected circuit in all cases.
  • Page 308 Section 3 1MRK504116-UUS C IED application Parallel line is out of service and grounded in both ends Apply the same measures as in the case with a single set of setting parameters. This means that an underreaching zone must not overreach the end of a protected circuit for the single phase-to-ground faults.
  • Page 309 Section 3 1MRK504116-UUS C IED application Load impedance limitation, without load encroachment function The following instructions is valid when the load encroachment function is not activated (OperationLdCmp is set to Off). If the load encroachment function is to be used for all or some of the measuring zones, the load limitation for those zones according to this chapter can be omitted.
  • Page 310 Section 3 1MRK504116-UUS C IED application This equation is applicable only when the loop characteristic angle for the single phase- to-ground faults is more than three times as large as the maximum expected load- impedance angle. More accurate calculations are necessary according to the equation below: é...
  • Page 311: Setting Parameters

    Section 3 1MRK504116-UUS C IED application Setting of timers for distance protection zones The required time delays for different distance-protection zones are independent of each other. Distance protection zone1 can also have a time delay, if so required for selectivity reasons. One can set the time delays for all zones (basic and optional) in a range of 0 to 60 seconds.
  • Page 312: Additional Distance Protection Directional Function For Earth Faults Zdardir

    Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description OperationDir Disabled Forward Operation mode of directionality NonDir / Non-directional Forw / Rev Forward Reverse 0.50 - 3000.00 ohm/p 0.01 40.00 Positive sequence reactance reach 0.10 - 1000.00 ohm/p 0.01 5.00...
  • Page 313 Section 3 1MRK504116-UUS C IED application wideness of the operating sector. The sector is mirror-symmetric along the MTA (Maximum Torque Axis). Directional elements for ground-faults must operate at fault current values below the magnitude of load currents. As phase quantities are adversely affected by load, the use of sequence quantities are preferred as polarizing quantities for ground directional elements.
  • Page 314 Section 3 1MRK504116-UUS C IED application current in the neutral of a power transformer. The relay characteristic AngleRCA is fixed and equals 0 degrees. Care must be taken to ensure that neutral current direction remains unchanged during all network configurations and faults, and therefore all transformer configurations/constructions are not suitable for polarization.
  • Page 315: Setting Parameters

    Section 3 1MRK504116-UUS C IED application 3.6.6.3 Setting parameters Table 66: ZDARDIR Group settings (basic) Name Values (Range) Unit Step Default Description IBase 1 - 99999 3000 Base setting for current values VBase 0.05 - 2000.00 0.05 400.00 Base setting for voltage level in kV PolMode -3U0 -3U0...
  • Page 316: Setting Guidelines

    Section 3 1MRK504116-UUS C IED application In the pilot channel blocking scheme a fault inception detected by a fast acting change detector is used to send a block signal to the remote end in order to block an overreaching zone. If the fault is later detected as a forward fault the earlier sent blocking signal is stopped.
  • Page 317: Setting Parameters

    Section 3 1MRK504116-UUS C IED application SIRLevel: The setting of the parameter SIRLevel is by default set to 10. This is a suitable setting for applications with CVT to avoid transient overreach due to the CVT dynamics. If magnetic voltage transformers are used, set SIRLevel to 15 the highest level. IMinOp: The minimum operate current for the SIR measurement is by default set to 20% of IBase.
  • Page 318: Application

    Section 3 1MRK504116-UUS C IED application 3.6.8.1 Application The operation of transmission networks today is in many cases close to the stability limit. Due to environmental considerations the rate of expansion and reinforcement of the power system is reduced for example, difficulties to get permission to build new power lines.
  • Page 319 Section 3 1MRK504116-UUS C IED application I1LowLevel: The setting of the positive current threshold I1LowLevel used in the sequence based part of the phase selector for identifying three-phase fault, is by default set to 10% of IBase. The default setting is suitable in most cases, but must be checked against the minimum three-phase current that occurs at remote end of the line with reasonable fault resistance.
  • Page 320 Section 3 1MRK504116-UUS C IED application RLdFw LdAngle LdAngle LdAngle LdAngle RLdRv ANSI10000192_1_en.vsd ANSI10000192 V1 EN Figure 138: Load encroachment characteristic The calculation of the apparent load impedance Z and minimum load impedance load can be done according to equations: loadmin Zload = ×...
  • Page 321: Setting Parameters

    Section 3 1MRK504116-UUS C IED application æ ö LdAngle a ç ÷ è ø (Equation 240) EQUATION1623-ANSI V1 EN where: Pmax is the maximal active power transfer during emergency conditions and Smax is the maximal apparent power transfer during emergency conditions. The RLd can be calculated according to equation 241: ×...
  • Page 322: Distance Protection Zone, Quadrilateral Characteristic, Separate Settings Zmrpdis (21), Zmrapdis (21) And Zdrdir (21D)

    Section 3 1MRK504116-UUS C IED application Name Values (Range) Unit Step Default Description V2MinOp 1 - 100 Minimum operate negative sequence voltage for ph sel INRelPG 10 - 100 3I0 limit for release ph-g measuring loops in % of max phase current 3I0BLK_PP 10 - 100 3I0 limit for blocking phase-to-phase...
  • Page 323 Section 3 1MRK504116-UUS C IED application System grounding The type of system grounding plays an important role when designing the protection system. Some hints with respect to distance protection are highlighted below. Solid grounded networks In solidly grounded systems, the transformer neutrals are connected solidly to ground without any impedance between the transformer neutral and ground.
  • Page 324 Section 3 1MRK504116-UUS C IED application The high zero sequence current in solid grounded networks makes it possible to use impedance measuring technique to detect ground-fault. However, distance protection has limited possibilities to detect high resistance faults and should therefore always be complemented with other protection function(s) that can carry out the fault clearance in those cases.
  • Page 325 Section 3 1MRK504116-UUS C IED application detect high resistance faults and should therefore always be complemented with other protection function(s) that can carry out the fault clearance in this case. High impedance grounded networks In high impedance networks, the neutral of the system transformers are connected to the ground through high impedance, mostly a reactance in parallel with a high resistor.
  • Page 326 Section 3 1MRK504116-UUS C IED application en05000216_ansi.vsd ANSI05000216 V1 EN Figure 140: High impedance grounded network. The operation of high impedance grounded networks is different compared to solid grounded networks where all major faults have to be cleared very fast. In high impedance grounded networks, some system operators do not clear single phase-to- ground faults immediately;...
  • Page 327 Section 3 1MRK504116-UUS C IED application The infeed factor (I can be very high, 10-20 depending on the differences in source impedances at local and remote end. p*ZL (1-p)*ZL en05000217_ansi.vsd ANSI05000217 V1 EN Figure 141: Influence of fault current infeed from remote line end The effect of fault current infeed from remote line end is one of the most driving factors for justify complementary protection to distance protection.
  • Page 328 Section 3 1MRK504116-UUS C IED application necessary sensitivity of the distance protection. The function can also preferably be used on heavy loaded medium long lines. For short lines, the major concern is to get sufficient fault resistance coverage and load encroachment is not a major problem. So, for short lines, the load encroachment function could preferably be switched off.
  • Page 329 Section 3 1MRK504116-UUS C IED application The IED's ability to set resistive and reactive reach independent for positive and zero sequence fault loops and individual fault resistance settings for phase-to-phase and phase- to-ground fault together with load encroachment algorithm improves the possibility to detect high resistive faults without conflict with the load impedance, see figure 49.
  • Page 330 Section 3 1MRK504116-UUS C IED application experience mutual coupling, and some coupling exists even for lines that are separated by 100 meters or more. The mutual coupling does influence the zero sequence impedance to the fault point but it does not normally cause voltage inversion. It can be shown from analytical calculations of line impedances that the mutual impedances for positive and negative sequence are very small (<...
  • Page 331 Section 3 1MRK504116-UUS C IED application parallel line in service. parallel line out of service and grounded. parallel line out of service and not grounded. Parallel line in service This type of application is very common and applies to all normal sub-transmission and transmission networks.
  • Page 332 Section 3 1MRK504116-UUS C IED application FAULT en05000221_ansi.vsd ANSI05000221 V1 EN Figure 143: Class 1, parallel line in service. The equivalent zero sequence circuit of the lines can be simplified, see figure 52. IEC09000253_1_en.vsd IEC09000253 V1 EN Figure 144: Equivalent zero sequence impedance circuit of the double-circuit, parallel, operating line with a single phase-to-ground fault at the remote busbar.
  • Page 333 Section 3 1MRK504116-UUS C IED application The second part in the parentheses is the error introduced to the measurement of the line impedance. If the current on the parallel line has negative sign compared to the current on the protected line, that is, the current on the parallel line has an opposite direction compared to the current on the protected line, the distance function will overreach.
  • Page 334 Section 3 1MRK504116-UUS C IED applic