Protective Elements
After the decoupling functions have tripped so that the generator circuit breaker has been opened, some conditions
must be fulfilled by the network operator before the reconnection of the power generating unit may be performed.
These release conditions involve making sure that the mains voltages are within their valid value and frequency
ranges. Such a test can (or must) be performed via direct measurement of the mains side voltages or / and an
remote control release signal “External Release from PCC”.
Since the various network operators may require their individual release conditions for a (re-)connection to their
medium or high voltage networks there is a choice between three different release conditions:
1. »
V Internal Release
(Release after a test based on direct measurement of the mains voltages)
2. »
V Ext Release PCC«
(Release based on an external release signal from the PCC)
3. »
Both«
(Release if 1. and 2. are both fulfilled)
Voltage release by (self-) measured voltage values
This method can be used if the PCC is on the MV side.
If the PCC is on the MV side, the device can measure the phase to phase voltages on the mains side and decide if
the mains voltage has stabilized sufficiently for reconnection.
For this method the parameter »
V Ext Release PCC
Fk«
in the menu
[Protection Para\Set[x]\Intercon-Prot\ReCon\General settings] has to be set to »
inactive«
.
Additionally the parameter »
Reclosure. Release Cond«
in the menu
[Protection Para\Set[x]\Intercon-Prot\ReCon\Reclosure Release] has to be set to »
V internal release «
Voltage release via remote control connection from the PCC
The voltage has to be recovered at the PCC before the reconnection is done.
If the PCC is located in the HV level the distance to the PCC is in general large.
The information that the voltage is restored is to be transmitted via a remote
control signal to the distributed energy resource.
This method has to be used if the PCC is on the HV side.
This method can be used if the PCC is on the MV side.
If reconnection release based on the remote control signal from the PCC is required:
In the menu [Protection Para\Set[x]\Intercon-Prot\ReCon\General settings] the parameter
»V Ext Release
PCC Fc«
has to be set to
»active«
. With this setting the voltage release signal from the PCC is used (e. g.
signal via digital input).
Additionally the parameter
»Reclosure Release Cond«
in the menu
[Protection Para\Set[x]\Intercon-
Prot\ReCon\Release Para\Reconnect. Release Cond] has to be set to
»V Ext Release PCC«.
Moreover, the remote control release signal has to be assigned to the parameter
»V Ext Release PCC«
in the
menu
[Protection Para\Global Prot Para\Intercon-Prot\ReCon\General settings].
970 MCDGV4 DOK-HB-MCDGV4-2E
To Next Page
