EDR-5000
IM02602007E
Parameter Setting of Decoupling
To support the decreasing voltage (voltage drop) during faults the electric utilities require the following behavior by the
connected energy resources:
“During voltage dips under 85% of rated voltage (380/220/110 kV, e. g. 110 kV x 0.85 = 93.5 kV) and
simultaneous reactive-power demand at the PCC = point of common coupling (under-excited operation), the
connected energy resource has to be decoupled after 0.5 s.
The voltage value refers to the highest value of the three phase to phase voltages. The decoupling has to be
done at the generator circuit breaker.“
The reactive-power of the positive phase sequence system (Q1) is evaluated.
The voltage supervision only monitors the phase to phase voltages.
This prevents any influence on the measurement through neutral point
displacement in resonant earthed systems.
In the menu [Protection Para\Set[x]\Q->&U<] the »Decoupling« parameters can be set.
The reactive-power demand from the grid can be detected by two different methods. Therefor the decoupling method
»
QV-Method« has to be selected first.
•
Power Angle Supervision (method 1)
•
Pure Reactive Power Supervision (method 2)
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