What type of multi-level input filter is used in a 3-phase 30KW vienna PFC?

Thread Starter

Younes Thabet

Joined Jan 9, 2019
Hello all,

I have been checking this 30 kW Vienna PFC rectifier reference design and didn't understand why all of these filters are used for this kind of application, i mean half of the board is inductors and capacitors for the filters.
Screenshot 2023-06-10 232126.png

Can someone explain what type of filters are used? and why are used in this application in particular? Will any 30kW type of application require such filtering?.



Joined Jan 23, 2018
The filters are required to prevent the harmonic frequencies created by the switching action of the diodes from entering the power system. They are very important. The rapid switching of the diodes tends to generate harmonic frequencies.