Siemens SIPROTEC 4 User Manual

Before a release is granted, the following conditions are checked:
•
Is the reference voltage V
1
above the setting value Vmin, but below the maximum voltage Vmax?
•
Is the voltage V
2
above the setting value Vmin, but below the maximum voltage Vmax?
•
Is the voltage difference V
2
– V
1
within the permitted thresholddV SYNCHK V2>V1?
•
Is the voltage difference V
1
– V
2
within the permitted threshold dV SYNCHK V2<V1?
•
Are the two frequencies f
1
and f
2
within the permitted operating range f
N
± 3 Hz?
•
Is the frequency difference f
2
– f
1
within the permitted threshold df SYNCHK f2>f1?
•
Is the frequency difference f
1
– f
2
within the permitted threshold df SYNCHK f2<f1?
•
Is the angle difference α
2
– α
1
within the permitted threshold dα SYNCHK α2>α1?
•
Is the angle difference α
1
– α
2
within the permitted threshold dα SYNCHK α2<α1?
Synchronous / Asynchronous (only 7SJ64)
The operating mode ASYN/SYNCHRON uses the frequency slip of the two power systems (parameter F
SYNCHRON) to determine whether the power systems are asynchronous to each other ("Switching under Asyn-
chronous System Conditions") or synchronous ("Switching under Synchronous System Conditions"). The
synchronous condition is indicated by the message
Sync f syn (170.2332). If the systems are asynchro-
nous, the time window for switching is passed relatively quickly. Therefore, it is sensible to take the operating
time of the circuit breaker into account. Thus the device can issue the ON command at a time where asynchro-
nous conditions are still prevailing. As soon as the poles make contact the conditions will be synchronous.
It is also possible to generally take into account the operating time of the circuit breaker, i.e. also with
synchronous conditions prevailing.
Switching under Synchronous System Conditions
Switching under synchronous conditions means that the ON command will be released as soon as the charac-
teristic data (voltage difference, angle difference) are within the thresholds specified by configuration.
Before granting a release for closing under synchronous conditions, the following conditions are checked:
•
Is the reference voltage V
1
above the setting value Vmin, but below the maximum voltage Vmax?
•
Is the voltage V
2
to be synchronized above the setting value Vmin, but below the maximum voltage
Vmax?
•
Is the voltage difference V
2
– V
1
within the permitted threshold dV SYNC V2>V1?
•
Is the voltage difference V
1
– V
2
within the permitted threshold dV SYNC V2<V1?
•
Are the two frequencies f
1
and f
2
within the permitted operating range f
Nom
± 3 Hz?
•
Is the frequency difference smaller than the configured threshold frequency difference F SYNCHRON,
which defines the transition from synchronous to asynchronous systems??
•
Is the angle difference α
2
– α
1
within the permitted threshold dα SYNC α2> α1?
•
Is the angle difference α
1
– α
2
within the permitted threshold dα SYNC α2< α1?
As soon as all synchronism conditions are fulfilled, the message
25 Synchron is issued.
Switching under Asynchronous System Conditions
For switching under asynchronous system conditions the device determines the time for issuing the ON
command from the angle difference and the frequency difference such that the voltages (of busbar and
feeder) are identical at the instant the poles make contact. For this purpose the device must be informed of
the operating time of the circuit breaker for closing.
Before a release is granted, the following conditions are checked:
2.21.1.3
Functions
2.21 Synchronization Function
SIPROTEC 4, 7SJ62/64, Manual 293
C53000-G1140-C207-8, Edition 08.2016

Siemens SIPROTEC 4 Specifications

General

Brand	Siemens
Model	SIPROTEC 4
Category	Protection Device
Language	English