Setting Guidelines - ABB RELION 650 Series Applications Manual

1MRK 505 363-UEN A
used in the teleprotection scheme has switched on to forward direction, we will have an
unwanted operation of breaker B2 at B side.
IEC14000003 V1 EN-US
Figure 134: Current distribution for a fault close to B side when breaker B1 is opened
To handle this, the send signal CS or CSLx from B2 is held back until the reverse zone IRVLx has
reset and the
protection shall be connected to input IRVLx and the output IRVOPLx shall be connected to
input BLKCS on the communication function block ZCPSCH.
Weak-end infeed logic
Permissive communication schemes can basically operate only when the protection in the
remote IED can detect the fault. The detection requires a sufficient minimum fault current,
normally >20% of Ir. The fault current can be too low due to an open breaker or low short-
circuit power of the source. To overcome these conditions, weak-end infeed (WEI) echo logic is
used. The fault current can also be initially too low due to the fault current distribution. Here,
the fault current increases when the breaker opens in the strong terminal, and a sequential
tripping is achieved. This requires a detection of the fault by an independent tripping zone 1.
To avoid sequential tripping as described, and when zone 1 is not available, weak-end infeed
tripping logic is used.
The WEI function sends back (echoes) the received signal under the condition that no fault has
been detected on the weak-end by different fault detection elements (distance protection in
forward and reverse direction).
The WEI function can be extended to trip also the breaker in the weak side. The trip is achieved
when one or more phase voltages are low during an echo function.
Together with the blocking teleprotection scheme some limitations apply:
• Only the trip part of the function can be used together with the blocking scheme. It is not
possible to use the echo function to send the echo signal to the remote line IED. The echo
signal would block the operation of the distance protection at the remote line end and in
this way prevents the correct operation of a complete protection scheme.
• A separate direct intertrip channel must be arranged from remote end when a trip or
accelerated trip is given there. The intertrip receive signal is connected to input CRL.
• The WEI function shall be set to
give phase selection and trip the local breaker.
13.3.3

Setting guidelines

The parameters for the current reversal and weak-end infeed logic for phase segregated
communication function (ZC1WPSCH) 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.
Application manual
L1
A1
L2
A2
tDelayRev time has elapsed. To achieve this, the reverse zone on the distance
SBase ) are set in Global base values for settings function GBASVAL .
B1
B2
IEC14000003-1-en.vsd
OperationWEI = Echo&Trip . The WEI function block will then
IBase ), primary voltage ( UBase ) and primary
Section 13
Scheme communication
SEMOD156555-1 v2
SEMOD156562-5 v3
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