Variable Bench Switch Mode Power Supply

Have any designs for widely variable switch mode power supplies suitable for
use as bench power supplies been published? I've been looking at some
comercially available supplies but they're still way too pricey. Ideally I'd
like a supply that does 0-100V at 20A or 2KW with a constant current mode.
Going right down to 0V isn't essential and a maximum of 60V and 1KW would
still be great.

Scrim


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