Current Protection - ABB Relion 670 Series Product Manual

Generator protection REG670
Version 2.2
(C37.118) Phasor Measurement Data Streaming Protocol
Configuration.
Multiple PMU functionality can be configured in the IED,
which can stream out same or different data at different
reporting rates or different performance (service)
classes.

7. Current protection

Instantaneous phase overcurrent protection PHPIOC
The instantaneous three phase overcurrent (PHPIOC)
function has a low transient overreach and short
tripping time to allow use as a high set short-circuit
protection function.
Directional phase overcurrent protection, four steps
OC4PTOC
Directional phase overcurrent protection, four steps
(OC4PTOC) has an inverse or definite time delay for each
step.
All IEC and ANSI inverse time characteristics are
available together with an optional user defined time
characteristic.
The directional function needs voltage as it is voltage
polarized with memory. The function can be set to be
directional or non-directional independently for each of
the steps.
A second harmonic blocking level can be set for the
function and can be used to block each step individually.
Instantaneous residual overcurrent protection
EFPIOC
The Instantaneous residual overcurrent protection
(EFPIOC) has a low transient overreach and short
tripping times to allow the use for instantaneous earth-
fault protection, with the reach limited to less than the
typical eighty percent of the line at minimum source
impedance. EFPIOC is configured to measure the
residual current from the three-phase current inputs and
can be configured to measure the current from a
separate current input.
Directional residual overcurrent protection, four
steps EF4PTOC
Directional residual overcurrent protection, four steps
(EF4PTOC) can be used as main protection for phase-to-
earth faults. It can also be used to provide a system
back-up, for example, in the case of the primary
protection being out of service due to communication or
voltage transformer circuit failure.
EF4PTOC has an inverse or definite time delay
independent for each step.
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M13667-3 v20
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All IEC and ANSI time-delayed characteristics are
available together with an optional user-defined
characteristic.
EF4PTOC can be set to be directional or non-directional
independently for each step.
IDir, UPol and IPol can be independently selected to be
either zero sequence or negative sequence.
A second harmonic blocking can be set individually for
each step.
Directional operation can be combined together with
the corresponding communication logic in permissive or
blocking teleprotection scheme. The current reversal
and weak-end infeed functionality are available as well.
The residual current can be calculated by summing the
three-phase currents or taking the input from the
neutral CT.
EF4PTOC also provides very fast and reliable faulty
phase identification for phase selective tripping and
subsequent reclosing during earth fault.
Four step directional negative phase sequence
overcurrent protection NS4PTOC
Four step directional negative phase sequence
overcurrent protection (NS4PTOC) has an inverse or
definite time delay independent for each step
separately.
All IEC and ANSI time delayed characteristics are
available together with an optional user defined
characteristic.
The directional function is voltage polarized.
NS4PTOC can be set directional or non-directional
independently for each of the steps.
NS4PTOC can be used as main protection for
unsymmetrical fault; phase-phase short circuits, phase-
phase-earth short circuits and single phase earth faults.
NS4PTOC can also be used to provide a system backup
for example, in the case of the primary protection being
out of service due to communication or voltage
transformer circuit failure.
Directional operation can be combined together with
corresponding communication logic in permissive or
blocking teleprotection scheme. The same logic as for
directional zero sequence current can be used. Current
reversal and weak-end infeed functionality are available.
1MRK 502 074-BEN M
GUID-485E9D36-0032-4559-9204-101539A32F47 v6
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