Current And Voltage Selection For Cvgapc Function - ABB Relion 670 Series Applications Manual

Section 10
Multipurpose protection
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2. Two undercurrent steps with the following built-in features:
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3. Two overvoltage steps with the following built-in features
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4. Two undervoltage steps with the following built-in features
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All these four protection elements within one general protection function works independently
from each other and they can be individually enabled or disabled. However it shall be once more
noted that all these four protection elements measure one selected current quantity and one
selected voltage quantity (see table
protection elements and their individual stages. Sometimes in order to obtain desired application
functionality it is necessary to provide interaction between two or more protection elements/
stages within one CVGAPC function by appropriate IED configuration (for example, dead machine
protection for generators).
10.1.2.1

Current and voltage selection for CVGAPC function

CVGAPC function is always connected to three-phase current and three-phase voltage input in the
configuration tool, but it will always measure only the single current and the single voltage
quantity selected by the end user in the setting tool (selected current quantity and selected
voltage quantity).
The user can select, by a setting parameter
quantities shown in table 23.
Table 23:
Set value for parameter
"CurrentInput"
PhaseA
1
2 PhaseB
PhaseC
3
PosSeq
4
5 NegSeq
Table continues on next page
226
Definite time delay or Inverse Time Overcurrent TOC/IDMT delay for both steps
Second harmonic supervision is available in order to only allow operation of the
overcurrent stage(s) if the content of the second harmonic in the measured current is
lower than pre-set level
Directional supervision is available in order to only allow operation of the overcurrent
stage(s) if the fault location is in the pre-set direction (
during low-level polarizing voltage is settable (
Voltage restrained/controlled feature is available in order to modify the pick-up level of
the overcurrent stage(s) in proportion to the magnitude of the measured voltage
Current restrained feature is available in order to only allow operation of the overcurrent
stage(s) if the measured current quantity is bigger than the set percentage of the
current restrain quantity.
Definite time delay for both steps
Definite time delay or Inverse Time Overcurrent TOC/IDMT delay for both steps
Definite time delay or Inverse Time Overcurrent TOC/IDMT delay for both steps
Available selection for current quantity within CVGAPC function
Comment
CVGAPC function will measure the phase A current phasor
CVGAPC function will measure the phase B current phasor
CVGAPC function will measure the phase C current phasor
CVGAPC function will measure internally calculated positive sequence current
phasor
CVGAPC function will measure internally calculated negative sequence current
phasor
Non-Directional , Block , Memory )
23 and table 24). It is possible to simultaneously use all four-
CurrentInput , to measure one of the following current
1MRK 511 358-UUS A
Forward or Reverse ). Its behavior
Application manual
SEMOD53443-6 v3