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Negative reactive power un generator

Negative reactive power un generator

Negative reactive power un generator

(OP)
Hello
I have a two generators work toguether un line ,si one give a negative reactive power ,un thé circuit there is some VFDs
Questions:
1-is this ils dangerous for the generator
2- how to make this reactive power positive like a seconde generator
Best regards

RE: Negative reactive power un generator

The reactive power should be equal on both generators.
The load determines the rate of total reactive power.
Adjust the voltage settings to balance the reactive power between the generators.
Reactive current increases the total current through the generator. Usually if the current is below the nameplate current rating you are OK.
At times, in special circumstances, generators may be run at light load and very low power factor. (high capacitive reactive power).
This has been done to reduce the current and voltage drop on tansmission lines.
If a large generator is used for large reactive power, it is well to consult the capability diagram of the generator and stay within the allowed values.
This is seldom an issue with smaller reactive power unbalances.
Be aware that a sudden shift in reactive power sharing may be a sympton of excitation issues.
Google "Cross current compensation" for a standard circuit to automatically share reactive power between generators.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Negative reactive power un generator

(OP)
Thanks a lot

RE: Negative reactive power un generator

The generator with the negative var voltage is lower that the generator with positive var when running parallel. More information is needed to figure out where the problem is.What var sharing method are you using? Isochronous or droop.

The problem could also be the droop CT.

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