Base Quantities For Cvgapc Function; Application Possibilities - ABB Relion REC670 Applications Manual

Section 10
Multipurpose protection
Set value for parameter
"VoltageInput"
MaxPh-Ph
13
MinPh-Ph
14
UnbalancePh-Ph
15
It is important to notice that the voltage selection from table
regardless the actual external VT connections. The three-phase VT inputs can be connected to
IED as either three phase-to-earth voltages U
U , U
L1L2
as a setting parameter for the pre-processing block, which will then take automatically care
about it.
10.1.2.2

Base quantities for CVGAPC function

The parameter settings for the base quantities, which represent the base (100%) for pickup
levels of all measuring stages shall be entered as setting parameters for every CVGAPC
function.
Base current shall be entered as:
1. rated phase current of the protected object in primary amperes, when the measured
Current Quantity is selected from 1 to 9, as shown in table 23.
2. rated phase current of the protected object in primary amperes multiplied by √3 (1.732 x
Iphase), when the measured Current Quantity is selected from 10 to 15, as shown in table
23.
Base voltage shall be entered as:
1. rated phase-to-earth voltage of the protected object in primary kV, when the measured
Voltage Quantity is selected from 1 to 9, as shown in table 24.
2. rated phase-to-phase voltage of the protected object in primary kV, when the measured
Voltage Quantity is selected from 10 to 15, as shown in table 24.
10.1.2.3

Application possibilities

Due to its flexibility the general current and voltage protection (CVGAPC) function can be used,
with appropriate settings and configuration in many different applications. Some of possible
examples are given below:
1. Transformer and line applications:
•
•
•
•
•
202
& U VAB, VBC and VCA. This information about actual VT connection is entered
L2L3 L3L1
Underimpedance protection (circular, non-directional characteristic)
Underimpedance protection (circular mho characteristic)
Voltage Controlled/Restrained Overcurrent protection
Phase or Negative/Positive/Zero Sequence (Non-Directional or Directional)
Overcurrent protection
Phase or phase-to-phase or Negative/Positive/Zero Sequence over/under voltage
protection
Comment
CVGAPC function will measure ph-ph voltage phasor with the maximum
magnitude
CVGAPC function will measure ph-ph voltage phasor with the minimum
magnitude
CVGAPC function will measure magnitude of unbalance voltage, which is
internally calculated as the algebraic magnitude difference between the
ph-ph voltage phasor with maximum magnitude and ph-ph voltage
phasor with minimum magnitude. Phase angle will be set to 0° all the
time
, U & U
L1 L2
24 is always applicable
or three phase-to-phase voltages
L3
1MRK 511 358-UEN A
SEMOD53443-112 v3
SEMOD53443-136 v2
Application manual