Preprocessing Blocks (Smai); Calculating Settings For Global Base Values For Setting Function Gbasval; Calculating Settings For Busbar High Impedance Differential Protection Hzpdif (87) - ABB Relion 650 Series Applications Manual

1MRK 505 287-UUS B
3.1.3

Preprocessing blocks (SMAI)

It is possible to use frequency adapted fourier filtering in the preprocessing blocks. In this
application, the frequency is close to nominal. Therefore, the setting of the parameters
DFTReference and DFTRefExtOut (when available) is:
3.1.4 Calculating settings for global base values for setting function
GBASVAL
Each function uses primary base values for reference of settings. The base values are defined in
Global base values for settings function. It is possible to include six Global base values for settings
GBASVAL functions: Global base 1 – Global base 6. In this application only GBASVAL instance 1 is
used to define the base quantities. The high impedance differential protection does not require
global base values.
The parameters of the Global base values are set equal to the system primary rated values:
1. Set
2. Set
3. Set
3.1.5 Calculating settings for busbar high impedance differential
protection HZPDIF (87)
In this application, there is one busbar protection covering busbar section 1 (zone 1) and one
busbar protection covering busbar section 2 (zone 2). A third zone (zone 3) is connected to cover
the total switchyard (sections 1 and 2). This zone is used as a check zone that will release a trip
from either zone 1 or 2. The substation lay-out is shown in figure 5. The settings are identical for
both zones.
Figure 6
busbar 1 to the high impedance differential protection.
BUS2
ANSI11000096 V2 EN-US
Figure 6:
The differential circuit has high impedance given by the stabilizing resistance R. This resistance is
adjustable with a maximum value of 6.8 kΩ. In balanced conditions, normal load or external faults,
the voltage V
through the high impedance differential circuit R resulting in a high voltage. This will bring the CTs
into saturation but before that, the overcurrent detection will operate and release a trip.
Busbar protection REB650
Application manual
IBase to 600 A .
VBase to 145 kV .
SBase to 151 MVA .
shows the connections of the CTs of one phase of each feeder and the buscoupler of
R R
CT CT
R
CT
BUS1
Connection of the high impedance differential protection and external fault
is very small. In case of an internal fault, the unbalanced current tries to flow
R
© Copyright 2013 ABB. All rights reserved
InternalDftRef is used.
RL4
RL3
RL2
+
RL1
R
U
R
CT
R
87
-
Busbar
REB650 setting examples
GUID-A82039F1-9EB0-4D9E-8466-420C6C7B2593 v2
GUID-7DDFEE9C-3868-4506-BE44-98ED94F4BB23 v3
GUID-B4514D6A-CD5F-464B-A8AB-D76CB478EF82 v4
External Fault
R
L
R
CT
Saturated CT
ANSI11000096-2-en.vsd
Section 3
33