Siemens 6MD85, Manual

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synchronization stages is currently active via the binary signal
>Selection
(synchronization stage x). The
closing conditions are checked if the respective stage is activated via the
>Selection
binary signal and the
stage is activated.
The fault indication
Multiple selection
is issued upon simultaneous selection of different synchroniza-
tion stages. If several synchronization stages are activated and the input signal
>Selection
(synchronization
stage x) is missing at the starting time, a valid selection is awaited during the supervision time
Max.durat.
sync.process
. If this does not come, the process is terminated.
Different Voltage-Transformer Ratios of Both Parts of the Electrical Power System
The settings of the rated parameters of the transformer for the measuring points automatically takes the
different voltage-transformer transformation ratios of both parts of the electrical power system into account.
The
Voltage adjustment
parameter is not needed for this purpose.
Synchronization via a Transformer
There are systems in which a power transformer is located between the voltage measuring points of the circuit
breaker to be synchronized. The device automatically considers the different voltage stages by setting the
transformer ratios (within the measuring points).
A phase displacement must be taken into account based on the transformer vector group, via the
Angle
adjust. (transform.)
parameter.
The parameter is defined as -Δα = –(α2 – α1).
To calculate the Delta parameters, the voltage of side 2 is converted to the voltage of side 1 using to the
settings of both parameters.
In the Application and Setting Notes, several examples are provided for using both parameters.
Different Connection Types on Both Sides
If both of the measuring points used by the synchronization functions record different voltages of the 3-phase
system, the calculation of the phase displacement angle is automatically taken into consideration.
EXAMPLE:
The 1-phase measuring point connected with Sync-voltage 1 records the phase-to-phase voltage V
AB
. The 1-
phase measuring point connected with Sync-voltage 2 records V
A
. In this case the phase angle between V
AB
and V
A
takes into consideration the delta variable Δα during calculation..
This automation guarantees that several voltage sources can be switched between during running operation,
each of which records different voltages.
Application and Setting Notes (General)
Stage-Type Selection
The following 2 types of stage are available:
Stage Type Application
Synchrocheck stage Select this type of stage to issue, for example, an additional release
during an manual reclosing for safety reasons.
With this type, the variables ΔV, Δf and Δα are checked before
connecting the 2 parts of the power system.
6.4.4.2
Control Functions
6.4 Synchronization Function
368 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017