first off, why would you use a "Pulse Width Modulated" power supply in the first place???
i am not sure of its function as a programmable pulse generator/pulse amplifier.....which is what an edm power supply is......
and not a PWM amplifier.......
a benchtop pulse generator is a very good start.
if its programmable, even better.
5Khz to 55KHz 1us to 3us pulses
80 volt 20 amp pulse amplifier, is a good starting point.
in other words drive your homebrew pulse amplifier with your benchtop
pulse generator, and you have an edm power supply.
albiet basic, it will work just fine.
and you just keep building up from there.