Multipurpose Protection; Secondary System Supervision; Control - ABB RES670 Product Manual

Phasor measurement unit RES670 ANSI
Customized
Product version: 1.2

7. Multipurpose protection

General current and voltage protection CVGAPC
The General current and voltage protection (CVGAPC) can be
utilized as a negative sequence current protection detecting
unsymmetrical conditions such as open phase or unsymmetrical
faults.
CVGAPC can also be used to improve phase selection for high
resistive ground faults, outside the distance protection reach,
for the transmission line. Three functions are used, which
measures the neutral current and each of the three phase
voltages. This will give an independence from load currents and
this phase selection will be used in conjunction with the
detection of the ground fault from the directional ground fault
protection function.

8. Secondary system supervision

Current circuit supervision CCSRDIF (87)
Open or short circuited current transformer cores can cause
unwanted operation of many protection functions such as
differential, ground-fault current and negative-sequence current
functions.
It must be remembered that a blocking of protection functions
at an occurrence of open CT circuit will mean that the situation
will remain and extremely high voltages will stress the
secondary circuit.
Current circuit supervision (CCSRDIF, 87) compares the
residual current from a three phase set of current transformer
cores with the neutral point current on a separate input taken
from another set of cores on the current transformer.
A detection of a difference indicates a fault in the circuit and is
used as alarm or to block protection functions expected to give
unwanted tripping.
Fuse failure supervision SDDRFUF
The aim of the fuse failure supervision function (SDDRFUF) is to
block voltage measuring functions at failures in the secondary
circuits between the voltage transformer and the IED in order to
avoid unwanted operations that otherwise might occur.
The fuse failure supervision function basically has three different
algorithms, negative sequence and zero sequence based
algorithms and an additional delta voltage and delta current
algorithm.
The negative sequence detection algorithm is recommended for
IEDs used in isolated or high-impedance grounded networks. It
is based on the negative-sequence measuring quantities, a high
ABB
value of voltage without the presence of the negative-sequence
current 3I .
2
The zero sequence detection algorithm is recommended for
IEDs used in directly or low impedance grounded networks. It
is based on the zero sequence measuring quantities, a high
value of voltage 3V without the presence of the residual
0
current 3I .
0
For better adaptation to system requirements, an operation
mode setting has been introduced which makes it possible to
select the operating conditions for negative sequence and zero
sequence based function. The selection of different operation
modes makes it possible to choose different interaction
possibilities between the negative sequence and zero sequence
based algorithm.
A criterion based on delta current and delta voltage
measurements can be added to the fuse failure supervision
function in order to detect a three phase fuse failure, which in
practice is more associated with voltage transformer switching
during station operations.

9. Control

Logic rotating switch for function selection and LHMI
presentation SLGGIO
The logic rotating switch for function selection and LHMI
presentation (SLGGIO) (or the selector switch function block) is
used to get a selector switch functionality similar to the one
provided by a hardware selector switch. Hardware selector
switches are used extensively by utilities, in order to have
different functions operating on pre-set values. Hardware
switches are however sources for maintenance issues, lower
system reliability and an extended purchase portfolio. The logic
selector switches eliminate all these problems.
Selector mini switch VSGGIO
The Selector mini switch VSGGIO function block is a
multipurpose function used for a variety of applications, as a
general purpose switch.
VSGGIO can be controlled from the menu or from a symbol on
the single line diagram (SLD) on the local HMI.
IEC 61850 generic communication I/O functions DPGGIO
The IEC 61850 generic communication I/O functions (DPGGIO)
function block is used to send double indications to other
systems or equipment in the substation. It is especially used in
the interlocking and reservation station-wide logics.
Single point generic control 8 signals SPC8GGIO
The Single point generic control 8 signals (SPC8GGIO) function
block is a collection of 8 single point commands, designed to
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