ABB Relion 670 Series Applications Manual page 453

1MRK 511 401-UEN Rev. K
IEC99000043 V3 EN-US
Figure 229: Current distribution for a fault close to B side when all breakers are closed
IEC99000044 V3 EN-US
Figure 230: Current distribution for a fault close to B side when breaker at B1 is opened
When the breaker on the parallel line operates, the fault current on the healthy line is reversed.
The IED at B2 recognizes the fault in forward direction from reverse direction before breaker
operates. As IED at B2 already received permissive signal from A2 and IED at B2 is now
detecting the fault as forward fault, it will immediately trip breaker at B2. To ensure that
tripping at B2 should not occur, the permissive overreaching function at B2 needs to be
blocked by IRVL till the received permissive signal from A2 is reset.
The IED at A2, where the forward direction element was initially activated, must reset before
the send signal is initiated from B2. The delayed reset of output signal IRVL also ensures the
send signal from IED B2 is held back till the forward direction element is reset in IED A2.
16.5.2.2 Weak-end infeed logic
Figure 231
there is no fault current from node B. This causes that the IED at B cannot detect the fault and
trip the breaker in B. To cope with this situation, a selectable weak-end infeed logic is provided
for the permissive overreaching scheme.
Strong
source
A
IEC99000054 V3 EN-US
Figure 231: Initial condition for weak-end infeed
16.5.3 Setting guidelines
The parameters for the current reversal and weak-end infeed logic for residual overcurrent
protection function are set via the local HMI or PCM600.
Common base IED values for primary current (
power (
GlobalBaseSel : It is used to select a GBASVAL function for reference of base values.
Bay control REC670
Application manual
L1
A1
L2
A2
L1
A1
L2
A2
shows a typical system condition that can result in a missing operation. Note that
SBase ) are set in a Global base values for settings function GBASVAL.
© Copyright 2017 Hitachi Power Grids. All rights reserved
B1
B2
IEC9900043-2.vsd
B1
B2
IEC99000044-2.vsd
Weak
source
B
IEC99000054-3-en.vsd
IBase ), primary voltage (UBase) and primary
Section 16
Scheme communication
M15285-6 v5
IP15042-1 v1
M13933-4 v5
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