We have three of these drives on board, which I'm trying to make sense of. I've attached a schematic, but I couldn't find the value of the inductors, so I just wrote small and big. The small ones seem to have the same size, and the big one is BIG, I doubt I could lift it.

Why all these inductors and caps before going into to the dc link? And why an inductor after the frequency converter? And why the huge capacitor pack connected in star? It consists of a total of 6 x 67 uF caps. So many questions.

 

Take a look at page 17 of this document: https://www.siemens.com.tr/i/Assets...jileri/marine/Marine-Frequency-Converters.pdf

 

Very interesting! Thanks for the link.