ABB Relion REG670, Applications Manual

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8.4.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Pole slip protection PSPPPAM U
cos
78
8.4.2 Application
Normally, the generator operates synchronously with the power system, that is, all the
generators in the system have the same angular velocity and approximately the same
phase angle difference. If the phase angle between the generators gets too large the
stable operation of the system cannot be maintained. In such a case the generator loses
the synchronism (pole slip) to the external power system.
The situation with pole slip of a generator can be caused by different reasons.
A short circuit occurs in the external power grid, close to the generator. If the fault
clearance time is too long, the generator will accelerate so much, so the synchronism
cannot be maintained. The relative generator phase angle at a fault and pole slip,
relative to the external power system, is shown in figure
134 .
Section 8
1MRK 502 071-UEN -
Impedance protection
262 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual