SMPS Help

[AmpBuilder225]

Hi, I'm looking to build a SMPS for a class D amplifier. The supply needs to provide around 200V and 1-2A. Ideally it should be reasonably small (an inch or 2 high and up to 6 inches long).

I have made many fairly high voltage linear power supplies for valve amplifiers and a few other applications, but I am pretty new to switched mode amps and was looking for some guidance. I have done quite a bit of reasearch and found that the forward converter topology looks like a good starting point but all the existing designs I can find convert mains voltage down to something like 12V. Where is a good place to get the necessary high power parts from in the UK and does anybody have any ideas which might get my design progressing a bit better?

[Osvaldo de Banfield]

As Abraham Pressman says in his book, the forward converter may be with one or two transistors conducting simultaneously. In both cases, the trouble will be a large output smoothing inductor. Appears that flyback topology is more recommended for HV supplies.
There is another thread with a same theme:
Choke formula - Marty Brown

Regards.

[dangus]

I would be inclined to start with a known good power supply, then rewind the transformer and alter the feedback voltage divider so as to get 200V instead of 5V. Or if it's for a car amp, same thing, except use a common amp that you have docs for.

[AmpBuilder225]

Thanks for the replies - sounds like quite a good idea to modify an existing supply. I've got a few books like Osvaldo recommended and they're proving helpful. I need to do some more reading around the topic for now I think.

[Osvaldo de Banfield]

I´m planning to build a L6565 and STD7N60 quasi-resonant converter to test the performance of such a scheme.