High frequency with inverter back to back for dfig Wind generator

[Guilhermebr]

Hi.

The picture in attached was measurement from dranetz px5 in transformer with 3 winding.1 Winding in High voltage, 2 winding in 690v for inverter back to back and the 3 winding in 400 v for other loads where I did measurement.

The high frequency in sine wave measurmet can have relations with common mode from inverter back to back in 2 winding?

The inverter back to back is used for reactive Power, frequency control nas other things in dfig Wind generator

Guilherme S.

 

[jraef]

As inverters go, that's fairly clean looking, I've seen a lot worse. But to answer your question, yes, that's indicative of common mode noise resulting from the PWM firing.


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[itsmoked]

Just post the dang thing.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Guilhermebr]

I was think in a possible solution, use a new transformer HV/LV just 400V. HV is clean. there are problem if I use same ground in same transformers (Y/Yn ground)?