Controlled Switching Operations - Hitachi Relion 650 Series Technical Manual

1MRK 511 557-UEN Rev. A
9.3.7.4

Controlled switching operations

Upon receiving a controlled switching command, SSCPOW converts the target switching angles into
release instants for each circuit breaker pole, and transmits three different output commands with
these individual time stamps to the respective PBOs. The principle is outlined in
IEC19000899 V1 EN-US
Figure 40:
In Figure
reference for controlled switching of the circuit breaker. Point A represents a random instant of
switching command given by the user. Without controlled switching, the CB would close/open at point
C (random switching instant), which is presumably not ideal for the CB, the switched load, and/or
power quality. Controlled switching delays the CB operation command to occur at the optimal
switching instant (point D) to minimize the transients.
SSCPOW reacts to switching commands received (point A) at its inputs described in
switching command is received while the function is still executing another controlled switching
operation, the later command is ignored.
Table 46:
Interface
CMDOPEN
CMDCLOSE
Controlled closing and controlled opening operations are described separately below.
Controlled closing operations
Controlled closing is the technique of issuing the CB closing commands such that primary current is
initiated at a desired phase angle in each phase, to minimize switching transients.
For controlled closing of a CB, consider the reference voltage in
CB closing command (CMDCLOSE input) at point A, which is at a random phase angle of the
Technical Manual
random instant of
switching command
signal analysis
Principle of controlled switching
40, the analog signal displayed is either a voltage or current signal, which is used as a
Command inputs
Type
Input
Input
For proper execution of a controlled switching operation, SSCPOW requires the time
stamp when the original Close or Open signal input was activated. Therefore, if
inserting additional logic between the respective binary inputs (in the application
configuration) and the CMDOPEN / CMDCLOSE inputs of SSCPOW, make sure to
use only "QT" logic functions with propagation of quality and time information.
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random
A
switching
instant
breaker operating time
calculated time delay
B
release instant of
circuit breaker
Description
CB opening command (from binary input)
CB closing command (from binary input)
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Figure
optimal
C D
switching
instant
IEC19000899-1-en.vsdx
Table
GUID-BF5433EA-14EE-4F02-8A54-8FF531F65570 v2
Figure 40. When the user gives a
Section 9
Control
40.
46. If a
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