Scheme Communication Logic For Distance Or Overcurrent Protection Zcpsch - ABB REC670 Applications Manual

1MRK 511 401-UEN A
Section 15
15.1
15.1.1
15.1.2
Bay control REC670 2.2 IEC
Application manual
Scheme communication
Scheme communication logic for distance or
overcurrent protection ZCPSCH
Identification
Function description
Scheme communication logic for
distance or overcurrent protection
Application
To achieve fast fault clearing for a fault on the part of the line not covered by the
instantaneous zone 1, the stepped distance protection function can be supported
with logic that uses a communication channel.
One communication channel in each direction, which can transmit an on/off signal
is required. The performance and security of this function is directly related to the
transmission channel speed and security against false or lost signals.
Communication speed, or minimum time delay, is always of utmost importance
because the purpose for using communication is to improve the tripping speed of
the scheme.
To avoid false signals that could cause false tripping, it is necessary to pay
attention to the security of the communication channel. At the same time it is
important to pay attention to the communication channel dependability to ensure
that proper signals are communicated during power system faults, the time during
which the protection schemes must perform their tasks flawlessly.
The logic supports the following communications schemes:
• blocking schemes (blocking and delta blocking)
• permissive schemes (overreaching and underreaching)
• unblocking scheme and direct intertrip
A permissive scheme is inherently faster and has better security against false
tripping than a blocking scheme. On the other hand, a permissive scheme depend
Scheme communication
IEC 61850 IEC 60617
identification identification
ZCPSCH -
Section 15
IP15749-1 v3
M14854-1 v4
ANSI/IEEE C37.2
device number
85
IP15020-1 v1
M16866-3 v5
433