Signals - ABB RELION REX640 Technical Manual

1MRS759142 C
9.6.7
REX640
Technical Manual
In this application example, breaker NSCB2 must be closed, so the synchronizing
conditions between the Bus1 and Bus2 power systems are checked by the
autosynchronizer for network breaker function ASNSCSYN. If the synchro check
conditions are not met, then ASNSCSYN sends the auto synchronization request and
voltage and frequency difference (ΔU, ΔF) between Bus1 and Bus2 to the
autosynchronizer co-ordinator function ASCGAPC.
ASCGAPC transfers the voltage and frequency difference sent by ASNSCSYN to the
ASCGAPC of the generator1 ASGCSYN function. It also sends permission to the
generator to start matching the voltage and frequency. The generator's ASGCSYN
function gives the raise or lower pulses to AVR and governor to raise or lower their
voltage and frequency on Bus2. The matching process is carried out so that the voltage
and frequency difference between Bus1 and Bus2 measured by ASNSCSYN reduces
and comes within the synchro check limits. This satisfies the synchro check conditions
for breaker NSCB2 which can then be synchronized by ASNSCSYN.
Voltage angle difference adjustment
In applications where the power transformer is located between the voltage
measurement and the generator circuit breaker, the vector group connection gives
phase difference to the voltages between the high- and low-voltage sides. The angle
adjustment can be used to meet synchronism.
The vector group of the power transformer is defined with clock numbers, where the
value of the hour pointer defines the low-voltage side phasor and the high-voltage side
phasor is always fixed to the clock number 12, which is the same as zero. The angle
between clock numbers is 30º. When comparing phase angles, the U_BUS input is
always the reference. This means that when the Yd11 power transformer is used, the
low-voltage side voltage phasor leads the high-voltage side phasor by 30º or lags by
330º. The rotation of the phasors is counterclockwise.
The generic rule is that a low-voltage side phasor lags the high-voltage side phasor by
clock number ⋅ 30º. This is called angle difference adjustment and can be set for
ASGCSYN with the Phase shift setting.

Signals

Table 1359: ASGCSYN Input signals
Name Type
U3P1 SIGNAL
U3P2 SIGNAL
BLOCK BOOLEAN
CL_COMMAND BOOLEAN
EXT_CHECK BOOLEAN
BYPASS BOOLEAN
GCB_TEST BOOLEAN
Table continues on next page
Default Description
- Three-phase voltages (generator side)
- Three-phase voltages (bus side)
0=False Blocking signal of the auto synchronization function
0=False External closing request
0=False External permissive check for CB close
0=False Request to bypass synchronism check and voltage
check
0=False Circuit breaker test position status
Section 9
Control functions
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