Identification; Application; Setting Guidelines - ABB RED650 Applications Manual

1MRK 505 393-UEN B
8.7.1
8.7.2
8.7.3
Line differential protection RED650 2.2 IEC
Application manual

Identification

Function description
Pole discordance protection

Application

There is a risk that a circuit breaker will get discordance 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 discordance 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 earth-
fault protections in the power system.
It is therefore important to detect situations with pole discordance of circuit
breakers. When this is detected the breaker should be tripped directly.
Pole discordance protection CCPDSC 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 discordance.
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 CurrUnsymLevel this is an
indication of pole discordance, and the protection will operate.

Setting guidelines

The parameters for the Pole discordance protection CCPDSC are set via the local
HMI or PCM600.
The following settings can be done for the pole discordance protection.
GlobalBaseSel: Selects the global base value group used by the function to define
IBase, UBase and SBase as applicable.
Operation: Off or On
Current protection
IEC 61850 IEC 60617
identification identification
CCPDSC
PD
SYMBOL-S V1 EN-US
Section 8
M14888-1 v4
ANSI/IEEE C37.2
device number
52PD
M13270-3 v6
M13274-3 v8
187