CHAPTER 5: SETTINGS
CONTROL ELEMENTS
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL
5-265
5
The synchronism check function supervises the paralleling of two parts of a system that are to be joined by the closure of
a circuit breaker. The synchrocheck elements are typically used at locations where the two parts of the system are
interconnected through at least one other point in the system.
Synchrocheck verifies that the voltages (V1 and V2) on the two sides of the supervised circuit breaker are within set limits
of magnitude, angle, and frequency differences. The time that the two voltages remain within the admissible angle
difference is determined by the setting of the phase angle difference
ΔΦ
and the frequency difference
Δ
F (slip frequency). It
can be defined as the time it takes the voltage phasor V1 or V2 to traverse an angle equal to 2
×
ΔΦ
at a frequency equal
to the frequency difference
Δ
F. This time is calculated by:
Eq. 5-23
where
ΔΦ
is phase angle difference in degrees
Δ
F is frequency difference in Hz
If one or both sources are de-energized, the synchrocheck programming can allow for closing of the circuit breaker using
undervoltage control to bypass the synchrocheck measurements (dead source function).
SYNCHK1 V1 SOURCE
— This setting selects the source for voltage V1 (see the Notes section that follows).
SYNCHK1 V2 SOURCE
— Selects the source for voltage V2, which must not be the same as used for the V1 (see Notes).
SYNCHK1 MAX FREQ
HYSTERESIS: 0.06 Hz
Range: 0.00 to 0.10 Hz in steps of 0.01
SYNCHK1 SYNC CLOSE:
Off
Range: FlexLogic operand
SYNCHK1 S-CLS MAX
dF: 0.50 Hz
Range: 0.10 to 2.00 Hz in steps of 0.01
SYNCHK1 S-CLS MIN
dF: 0.10 Hz
Range: 0.01 to 1.00 Hz in steps of 0.01
SYNCHK1 S-CLS BRK
TIME: 0.035 s
Range: 0.010 to 0.500 s in steps of 0.001
SYNCHK1 V2 MAG CORR
FACTOR: 1.00
Range: 0.10 to 10.00 in steps of 0.01
SYNCHK1 V2 ANGLE
SHIFT: 0
Range: -180 to +180 degrees in steps of 1
SYNCHK1 DEAD SOURCE
SELECT: LV1 and DV2
Range: None, LV1 and DV2, DV1 and LV2, DV1 or DV2,
DV1 Xor DV2, DV1 and DV2
SYNCHK1 DEAD V1
MAX VOLT: 0.30 pu
Range: 0.04 to 1.25 pu in steps of 0.01
SYNCHK1 DEAD V2
MAX VOLT: 0.30 pu
Range: 0.04 to 1.25 pu in steps of 0.01
SYNCHK1 LIVE V1
MIN VOLT: 0.70 pu
Range: 0.04 to 1.25 pu in steps of 0.01
SYNCHK1 LIVE V2
MIN VOLT: 0.70 pu
Range: 0.04 to 1.25 pu in steps of 0.01
SYNCHK1 TARGET:
Self-reset
Range: Self-reset, Latched, Disabled
SYNCHK1 EVENTS:
Disabled
Range: Disabled, Enabled