Algorithm - GE Multilin F650 Instruction Manual

5 SETPOINTS
SLIP CONDITION: I
BUS FREQ > LINE FREQ:
BUS FREQ < LINE FREQ:
Voltage and frequency values for line and busbar can be obtained, both in primary and secondary values at:
Actual> Metering > Primary Values > Voltage
VBB Primary (KV)
VL Primary (KV)
Actual> Metering > Secondary Values > Voltage
Line Voltage (V)
Bus Voltage (V)
Actual> Metering > Frequency
Line Frequency (Hz)
Bus Frequency (Hz)
Note on the measure: voltage and current angles are available for the user from firmware version 1.60.
The voltage angles can be obtained in primary metering values (Actual> Metering > Primary Values > Voltage), being the
line voltage angle, the one that corresponds to the voltage set in the frequency reference in General setpoints (please refer
to the voltage correspondence table (Table 5–71:), and the angle of the busbar voltage the one that corresponds to Vx
Angle, when the Auxiliary Voltage setpoint as been selected as VX.

5.5.4.5 ALGORITHM

F650 units perform the synchronism check by basically establishing and comparing three parameters:
Module difference of voltage phasors ΔV (V)
Phase angle of voltage phasors Δϕ (º)
Frequency slip between two phasors S (Hz)
These parameters are continuously determined and managed once that Unit 25 has been enabled by setpoint, and
in open breaker conditions. It is necessary to consider that all calculations are made once the open breaker condition is
detected; if the breaker is closed or undefined, the synchronism unit will not issue a closing permission signal, even when
closing conditions are met.
If voltage on one side of the breaker to be closed is null, the synchronism unit cannot establish the synchronism check, and
therefore it will not issue synchronism permission. For these cases, usual in breaker maintenance situations, or in new
installations where voltage might not be present, but the breaker operation needs to be verified, F650 units incorporate
closing permission logics for situations of:
Dead Line – Dead Bus (DL-DB)
Live Line – Dead Bus (LL-DB)
Dead Line – Live Bus (DL-LB)
In order to establish the closing permission signal, the first parameter used by the algorithm is the difference in magnitude
between line and bus voltages, and afterwards, the angle difference and frequency slip are verified.
Δ
Voltage Difference V
GE Multilin
DL-LB OPERATION: Closing permission in dead line – live bus condition.
LL-DB OPERATION: Closing permission in live line – dead bus condition.
Internal signal indicating frequency slip between the line voltage and bus voltage
phasors.
Busbar Frequency higher than line frequency
Busbar Frequency lower than line frequency
Busbar voltage in primary values
Line voltage in primary values
Line voltage in secondary values
Busbar voltage in secondary values
Line frequency in Hz
Bus frequency in Hz
F650 Digital Bay Controller
5.5 CONTROL ELEMENTS
5-83
5