De-Energized Switching - Siemens SIPROTEC 4 User Manual

Functions
2.21 Synchronization Function
•
Is the reference voltage V
•
Is the voltage V
Vmax?
•
Is the voltage difference V
•
Is the voltage difference V
•
Are the two frequencies f
•
Is the frequency difference f
•
Is the frequency difference f
When the check has been terminated successfully, the device determines the next instant at which the two
systems are in phase from the angle difference and the frequency difference. The ON command is issued at
this instant minus the operating time of the circuit breaker.
2.21.1.4

De-energized Switching

Connecting two components of a power system is also possible if at least one of the components is de-ener-
gized and if the measured voltage is greater than the threshold 6106 V>, with a multiple-phase connection at
side V all three voltages must have a higher value than threshold V> so that side V
1
gized. With single-phase connection, of course, only one voltage has to exceed the threshold value.
Besides release under synchronous conditions, the following additional release conditions can be selected for
the check:
SYNC V1>V2< =
SYNC V1<V2> =
SYNC V1<V2< =
Each of these conditions can be enabled or disabled individually; combinations are thus also possible (e.g.,
release if SYNC V1>V2< or SYNC V1<V2> are fulfilled).
For that reason synchronization with the use of the additional parameter 6x13 25 Synchron (configured to
NO) can also be used for the connection of a ground electrode. In such a case, one may only connect when
there is no voltage on the load side, i.e. under synchronous conditions no connection is permitted.
The release conditions can be configured individually either for automatic reclosing or for manual closing via
control commands. You can, for example, allow manual closing for synchronism or for de-energized feeder
whereas before an automatic reclosing operation, checking only de-energized conditions at one feeder
terminal and afterwards only synchronism at the other.
The threshold below which a power system component is considered as de-energized is defined by parameter
V<. If the measured voltage exceeds the threshold V>, a power system component is energized. Thus, with a
multiple-phase connection at side V
side V is recognized as energized. With single-phase connection only one voltage has to exceed the threshold
1
value.
Before granting a release for connecting the energized component V
the following conditions are checked:
•
Is the reference voltage V
•
Is the voltage to be synchronized V
•
Is the frequency f
After successful termination of the check the release is granted.
294
above the setting value Vmin, but below the maximum voltage Vmax?
1
to be synchronized above the setting value Vmin, but below the maximum voltage
2
– V within the permitted threshold dV ASYN V2>V1?
2 1
– V within the permitted threshold dV ASYN V2<V1?
1 2
and f within the permitted operating range f
1 2
– f within the permitted threshold df ASYN f2>f1?
2 1
– f within the permitted threshold df ASYN f2<f1?
1 2
Release on the condition that component V
gized.
Release on the condition that component V
gized.
Release on the condition that component V
all three voltages must have a higher value than threshold V> so that
1
above the setting value Vmin and V>, but below the maximum voltage Vmax?
1
below the thresholdV<?
2
within the permitted operating range f
1
± 3 Hz?
Nom
is recognized as ener-
1
is energized and component V
1
is de-energized and component V
1
and component V are de-energized.
1 2
and the de-energized component V
1
± 3 Hz?
Nom
SIPROTEC 4, 7SJ62/64, Manual
C53000-G1140-C207-8, Edition 08.2016
is de-ener-
2
is ener-
2
,
2