ABB RELION 670 SERIES REG670 - Pole Discrepancy Protection CCPDSC(52 PD); Identification; Application

tPulse: Trip pulse duration. This setting must be larger than the critical impulse time of
circuit breakers to be tripped from the breaker failure protection. T
ypical setting is 200
ms.
9.9 Pole discrepancy protection CCPDSC(52PD)
IP14516-1 v5
9.9.1 Identification
M14888-1 v4
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Pole discrepancy protection CCPDSC
PD
SYMBOL-S V1 EN-US
52PD
9.9.2 Application
M13270-3 v6
There is a risk that a circuit breaker will get discrepancy
between the poles at circuit
breaker operation: closing or opening. One pole can be open and the other two closed,
or two poles can be open and one closed. Pole discrepancy of a circuit breaker will
cause unsymmetrical currents in the power system. The consequence of this can be:
• Negative sequence currents that will give stress on rotating machines
• Zero sequence currents that might give unwanted operation of sensitive ground-
fault protections in the power system.
It is therefore important to detect situations with pole discrepancy of circuit breakers.
When this is detected the breaker should be tripped directly.
Pole discordance protection CCPDSC (52PD) will detect situation with deviating
positions of the poles of the protected circuit breaker. The protection has two different
options to make this detection:
• By connecting the auxiliary contacts in the circuit breaker so that logic is created,
a signal can be sent to the protection, indicating pole discrepancy. This logic can
also be realized within the protection itself, by using opened and close signals for
each circuit breaker pole, connected to the protection.
• Each phase current through the circuit breaker is measured. If the difference
between the phase currents is larger than a CurrUnsymPU this is an indication of
pole discrepancy, and the protection will operate.
1MRK 502 071-UUS A Section 9
Current protection
Generator protection REG670 2.2 ANSI and Injection equipment REX060, REX061, REX062 403
Application manual