Synchronism Check - ABB Relion 670 Series Applications Manual

Section 13
Control
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
prevent incorrect closing pulses, a maximum closing angle between bus and line is preset
internally to a value of 15 degrees.
preset maximum closing angle of 15 degrees, at different allowed slip frequencies for
synchronizing.
Table 26: Dependencies between tBreaker and SlipFrequency with maximum closing angle of 15 degrees
tBreaker [s] (max settable value) with the internally
preset closing angle of 15 degrees
The reference voltage can be phase-neutral A, B, C or phase-phase A-B, B-C, C-A or positive
sequence (Require a three phase voltage, that is VA, VB and VC) . By setting the phases used for
SESRSYN, with the settings
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.
13.1.2.2

Synchronism check

The main purpose of the synchronism check function is to provide control over the closing of
circuit breakers in power networks in order to prevent closing if conditions for synchronism are
not detected. It is also used to prevent the re-connection of two systems, which are divided after
islanding and after a three pole reclosing.
SESRSYN (25) function block includes both the synchronism check function and the energizing
function to allow closing when one side of the breaker is dead. SESRSYN (25) function also
includes a built in voltage selection scheme which allows adoption to various busbar
arrangements.
254
Table 26
0.040
0.050
0.080
0.200
0.400
0.800
1.000
SelPhaseBus1 , SelPhaseBus2 , SelPhaseLine2 and SelPhaseLine2 , a
Single pole auto-reclosing does not require any synchronism check since the
system is tied together by two phases.
SlipFrequency and the set tBreaker time. To
shows the maximum settable value for
SlipFrequency [Hz] (BusFrequency - LineFrequency)
1MRK 511 358-UUS A
tBreaker at the
1.000
0.800
0.500
0.200
0.100
0.050
0.040
M12309-6 v9
Application manual