GE 850 - Page 512

8–40 850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
SYNCHROCHECK (25) CHAPTER 8: CONTROL
Figure 8-20: Synchrocheck logic diagram
892754A2.cdr
SETPOINT
FUNCTION: Enabled
FlexLogic Operands
Sync1 OK
SETPOINTS
Do Not Operate, Operate OUTPUT RELAYS3 to 7
ΔV <= MAX VOLTS DIFF
AND
SETPOINT
BLOCK : Off = 0
Magnitude Vbv Disabled
SETPOINTS
MAX VOLT DIFFERENCE:
SETPOINT
DEAD SOURCE PERM: Disabled L BUS & D LINE L LINE & D BUS
Sync1 Dead Src OK
Phase Φbv Frequency fbv Magnitude Vlv Phase Φlv Frequency flv
ΔV=|V3phv –V1phv|
Δf=|f
3phv –f1phfv|
ΔΦ=|(Φ
3phv – Φ1phv)|
MAX FREQ DIFFERENCE: MAX ANGLE DIFFERENCE:
Δf <= MAX FREQ DIFF
ΔΦ <= MAX ANGLE DIFF
Vbus >= LIVE BUS V MIN
SETPOINT
LIVE BUS VOLTS MIN:
Vline >= LIVE LINE V MIN
SETPOINT
LIVE LINE VOLTS MIN:
Vbus<=DEAD BUS V MAX
SETPOINT
DEAD BUS VOLTS MAX:
Vline<=DEAD LINE V MAX
SETPOINT
DEAD LINE VOLTS MAX: D LINE & D BUS D LINE OR D BUS D LINE XOR D BUS
OR XOR
AND AND AND AND AND
OR
ANDAND AND AND AND AND
OR
Sync1 Close Perm Sync1 Live Bus Sync1 Live Line Sync1 Dead Bus Sync 1Dead Line
MAX FREQ HYSTERESES:
TO: Autoreclose Undervoltage restoration Underfrequency restoration Manual local/remote closing TO: Transfer Scheme
Bus (Line) voltage Associated setpoints from System/Voltage Sensing/ Phase VT connection Line (Bus) voltage Associated setpoints from System/Voltage Sensing/ Aux VT connection
Transfer Initiate
from Tie -Breaker Transfer scheme
from Breaker State Detection
BKR 1 Disconnected