ABB REB670 Series Applications Manual page 256

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Section 12
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
time. To prevent incorrect closing pulses, a maximum closing angle between bus and line is set
CloseAngleMax . Table
with
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
Table 40: Dependencies between tBreaker and SlipFrequency with different CloseAngleMax values
tBreaker [s] (max settable value)
with
CloseAngleMax = 15 degrees
[default value]
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
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
12.1.2.2
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 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 function block includes both the synchrocheck function and the energizing function
to allow closing when one side of the breaker is dead. SESRSYN function also includes a built in
voltage selection scheme which allows adoption to various busbar arrangements.
250
40
below shows the maximum settable value for
CloseAngleMax needs to be used.
tBreaker [s] (max settable value) with
CloseAngleMax = 30 degrees [max
value]
0.040
0.050
0.080
0.200
0.400
0.800
1.000
PhaseShift setting.
Single pole auto-reclosing does not require any synchrocheck since the system
is tied together by two phases.
SlipFrequency and the set tBreaker
SlipFrequency [Hz]
(BusFrequency - LineFrequency)
0.080
0.100
0.160
0.400
0.810
1.000
SelPhaseBus1 , SelPhaseBus2 , SelPhaseLine2 and
1MRK 505 370-UEN D
tBreaker when
1.000
0.800
0.500
0.200
0.100
0.080
0.050
0.040
M12309-6 v10
Busbar protection REB670
Application manual

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