Synchrocheck - ABB REG670 Applications Manual

Section 15
Control
15.1.2.2
480
frequencies must also be within a range of ±5 Hz from the rated frequency. When
the synchronizing option is included also for autoreclose there is no reason to
have different frequency setting for the manual and automatic reclosing and the
frequency difference values for synchronism check should be kept low.
• The frequency rate of change is less than set value for both U-Bus and U-Line.
• The difference in the phase angle is smaller than the set value of CloseAngleMax.
• The closing angle is decided by the calculation of slip frequency and required pre-
closing time.
The synchronizing function compensates for the measured slip frequency as well as
the circuit breaker closing delay. The phase angle advance is calculated continuously.
The calculation of the operation pulse sent in advance is using the measured
SlipFrequency and the set tBreaker time. To prevent incorrect closing pulses, a
maximum closing angle between bus and line is set with CloseAngleMax. Table
below shows the maximum settable value for tBreaker when CloseAngleMax is set to
15 or 30 degrees, at different allowed slip frequencies for synchronizing. To minimize
the moment stress when synchronizing near a power station, a narrower limit for the
CloseAngleMax needs to be used.
Table 51: Dependencies between tBreaker and SlipFrequency with different CloseAngleMax
values
tBreaker [s] (max settable value)
CloseAngleMax = 15
with
degrees [default value]
0.040
0.050
0.080
0.200
0.400
0.800
1.000
The reference voltage can be phase-neutral L1, L2, L3 or phase-phase L1-L2, L2-L3,
L3-L1 or positive sequence (Require a three phase voltage, that is UL1, UL2 and
UL3) . By setting the phases used for SESRSYN, with the settings SelPhaseBus1,
SelPhaseBus2, SelPhaseLine2 and SelPhaseLine2, a compensation is made
automatically for the voltage amplitude difference and the phase angle difference
caused if different setting values are selected for the two sides of the breaker. If needed
an additional phase angle adjustment can be done for selected line voltage with the
PhaseShift setting.

Synchrocheck

The main purpose of the synchrocheck function is to provide control over the closing
of circuit breakers in power networks in order to prevent closing if conditions for
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
tBreaker [s] (max settable value)
CloseAngleMax = 30 degrees
with
[max value]
0.080
0.100
0.160
0.400
0.810
1.000
1MRK 502 071-UEN -
51
SlipFrequency [Hz]
(BusFrequency -
LineFrequency)
1.000
0.800
0.500
0.200
0.100
0.080
0.050
0.040
Application manual