ABB RELION REX640 - Synchro check

Synchro
check
Close CB
condion
Synchroni-
zaon
control
Alarms
generaon
CL_COMMAND
BYPASS
EXT_CHECK
CB_TEST
CB_CLOSE
BLOCK
CB_OPEN
ISO_A_CLOSE
ISO_B_CLOSE
MATCH_OK
MATCH_INPRO
SYNC_OK
CLOSE_CB
CL_FAIL_AL
CMD_FAIL_AL
ENERG_STATE From
Energizing check
SYNC_INPRO
U3P1
U3P2
U_A_AB
U_B_BC
U_C_CA
U_A_AB
Figure 855: Module diagram for Synchronization check and control
Synchro check
The function measures the voltage difference U_DIFF_MEAS, frequency difference
FR_DIFF_MEAS and phase angle difference PH_DIFF_MEAS between the bus voltage
and generator voltage. In the calculation of PH_DIFF_MEAS, setting Phase shift
is used to compensate the angle shift caused if a power transformer is located
between the voltage measurements. Offset correction due to different channel
measurements (for voltage and frequency values) can be done using Voltage
offset and Frequency offset . The user can select the direction of generator
synchronization using the setting Synchronization Dir .
U DIFF MEAS U U Voltage offset
Gen Bus
_ _ = − −
(Equation 353)
U
Bus
Measured bus side voltage
U
Gen
Measured generator side voltage
Voltage off-
set
Setting Voltage offset
FR DIFF MEAS f f Frequency offset
Gen Bus
_ _ = − −
(Equation 354)
f
Bus
Measured bus side frequency
f
Gen
Measured generator side frequency
Frequency
offset
Setting Frequency offset
1MRS759142 F Control functions
REX640
Technical Manual
1561