PFC - when do you need it

[kubeek]

I am in the process of bulding a cca 750-1kW PSU for commercial amp purposes, and I am wondering if I really need to implement PFC. Not because of the actual power factor because that is not my concern, but because of the harmonics that are sent to the power lines, in which the PFC should help.

This is my first off-line project, so I want to keep things simple. Do you think it is necessary to use PFC to get within the ragulations, or is a simple line filter enough?

 

[kubeek]

So here is a list of pros and cons:

+ should work with wider supply range
+ better EMC compatibility

- cca 50-100V higher voltage on the bulk caps than usual, also affects transistor selection
- more complex
- higher weight from the large inductor

So I think that I am better off without it, any thoughts?

 

[MicrosiM]

Pfc

So here is a list of pros and cons:

+ should work with wider supply range
+ better EMC compatibility

- cca 50-100V higher voltage on the bulk caps than usual, also affects transistor selection
- more complex
- higher weight from the large inductor

So I think that I am better off without it, any thoughts?

Yes, its true

PFC is costy and it will really cost you lot of money + no much informations can be found at the web regarding how to make PFC, specially to select the proper magnitics.

If your SMPS is 1000W, I dont think it worth to spend around 1000US$ for prototypes, unless you are lucky from first time.

Those line filters, found in many amplifiers can do the JOB, without problems.

If you can afford paying + if you have time then do it, In my last SMPS I stopped working with PFC due the problems I faced into getting custom inductors.

Good Luck!