Operation Principle - ABB REG650 Technical Manual

1MRK 502 043-UUS B
Table 37: GENPDIF (87G) Group settings (advanced)
Name Values (Range)
EndSection1 0.20 - 1.50
EndSection2 1.00 - 10.00
SlopeSection2 10.0 - 50.0
SlopeSection3 30.0 - 100.0
NegSeqROA 30.0 - 120.0
HarmDistLimit 5.0 - 100.0
OpCrossBlock No
Yes
AddTripDelay 0.000 - 60.000
OperDCBiasing Disabled
Enabled
OpenCTEnable Disabled
Enabled
tOCTAlarmDelay 0.100 - 10.000
tOCTResetDelay 0.100 - 10.000
tOCTUnrstDelay 0.100 - 100.000
TempIdMin 1.0 - 5.0
Table 38: GENPDIF (87G) Non group settings (basic)
Name Values (Range)
GlobalBaseSel 1 - 6
6.3.6
Technical Manual
Unit Step
IB 0.01
IB 0.01
% 0.1
% 0.1
Deg 0.1
% 0.1
- -
s 0.001
- -
- -
s 0.001
s 0.001
s 0.001
IdMin 0.1
Unit Step
- 1

Operation principle

The task of Generator differential protection GENPDIF (87G) is to determine whether
a fault is within the protected zone, or outside the protected zone. The protected zone is
delimited by the position of current transformers, as shown in figure 46.
Default Description
1.25 End of section 1, multiple of generator rated
current
3.00 End of section 2, multiple of generator rated
current
40.0 Slope in section 2 of operate-restrain
characteristic, in %
80.0 Slope in section 3 of operate-restrain
characteristic, in %
60.0 Operate Angle of int/ext neg. seq. fault
discriminator, deg
10.0 (Total) relative harmonic distorsion limit,
percent
Yes Operation Enable/ Disable for cross-block
logic between phases
0.100 Additional trip delay, when input
raisePickUp=1
Disabled Operation DC biasing On / Off
Disabled Enable/Disable open CT detection
1.000 Open CT: time to alarm if an open CT is
detected, in sec
0.250 Reset delay in s. After delay, diff. function is
activated
10.000 Unrestrained diff. protection blocked after this
delay, in s
2.0 Temp. Id pickup when input raisePickUp=1,
multiple of IdMin
Default Description
1 Selection of one of the Global Base Value
groups
Section 6
Differential protection
117