Controlled Switching Strategies - Hitachi Relion 650 Series Technical Manual

1MRK 511 557-UEN Rev. A
The conditions for using the available reference signal and for declaring missing reference are
summarized in
Table 42:
CB Status
Open
Open
Closed
Closed
Closed
Closed
9.3.7.3

Controlled switching strategies

The main purpose of SSCPOW is controlling CB switching operations to occur at a desired phase
angle of the reference signal in each phase. For a controlled closing operation, the function has the
provision to either apply user-defined target making angles (via settings CloseTargetLx) or to receive
the target making angles externally from other AFL functions (via inputs LD1CLANLx/ LD2CLANLx).
For a controlled opening operation, the settings OpenTargetLx alone define the target switching
angles. The next sub-sections describe how the function executes target switching angles for
controlled closing and opening operations separately.
Controlled opening operation with user-defined target angles
For a controlled opening operation, the target switching angles define the intended point of primary
contact separation in the CB. Based on the switching angles fed, SSCPOW issues open commands
once an input command is received.
The target phase angles for an open operation are specified through the settings described in
43.
Table 43:
Interface
OpenTargetL1
OpenTargetL2-L1
OpenTargetL3-L1
For example; if OpenTargetL1 = 60°, OpenTargetL2-L1 = -120° and OpenTargetL3-L1 = 90°, the lead
phase here is set as L2 and the contact separation instants are as shown in
Technical Manual
Table 42.
Use and status of reference signals
OpenRef VOLREFOK
(any)
(any)
Voltage
Voltage
Current
Current
User defined controlled opening targets
Type
Setting
Setting
Setting
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CURREFOK
1 (any)
0 (any)
1 (any)
0 (any)
(any) 1
(any) 0
Description
CB opening (i.e. contact separation) target in electrical
degrees relative to a positive-going zero crossing of the
selected reference signal, for phase L1
CB opening (i.e. contact separation) target in electrical
degrees relative to OpenTargetL1, for phase L2
CB opening (i.e. contact separation) target in electrical
degrees relative to OpenTargetL1, for phase L3
REFSIGLOS Reference signal
used
0 Source voltage
1 None
0 Source voltage
1 None
0 Load current
1 None
GUID-3F82917E-0763-4FD6-BA30-062A73BB8E28 v3
GUID-EB97862F-A073-47D1-B20F-787A320F3D08 v1
Figure 38.
Section 9
Control
Table
81