# filter circuit for three phase ac to dc converter.

Discussion in 'The Projects Forum' started by antony.prathiban, May 17, 2008.

1. ### antony.prathiban Thread Starter Member

May 14, 2008
24
0
i have to design a rectifier circuit.(three phase ac to dc).
the input is three phase ac supply of 415v,15amps, and 50hz.
now ,could you please anyone suggest regarding the filters design for this circuit and and how to calculate all those parameters.

2. ### 2ManyHobbies New Member

May 16, 2008
4
0
Given that you have a 3-phase input, the output should be fairly stable. What is your DC output current and max ripple voltage? It might be as simple as connecting an appropriately sized capacitor across the output.

Vr = I/(CF), but keep in mind that F depends on input frequency and your rectification method -- full bridge doubles the frequency, and 3-phase also makes things interesting...

3. ### thingmaker3 Retired Moderator

May 16, 2005
5,072
6
One rule of thumb for filter caps is C = 0.7(I)/ΔE(f) where ΔE is acceptable ripple voltage.

4. ### antony.prathiban Thread Starter Member

May 14, 2008
24
0
thanks a lot.