High Voltage, MCU controled 300Volt power supply

[amgen]

I would..... use triac or power mosfet, phase control or pwm. PiC can do all control, Vfb voltage feed back. current feed back and isolated opto drivers.... smooth the output as desired etc. sorry about messy drawing

[pedja089]

In video above, they use same system as you suggested. Only they have used isolation transformer.
In my opinion that schematic have high ripple and relatively large capacitance on output. So short circuit energy is very large... That means current control would have huge overshoot, until capacitor is discharged.
We don't know spec for PSU, that maybe acceptable, but not very nice solution in my opinion.
I definitely would go with minimal output capacitance, overshoot and ripple.
All that you can get from solution that I suggested.

[Ioannis]

Having a requirement of 400mA means a large output capacitor.

Also the problem of the wide duty cycle variation remains as we need 10-300 volt at the output.

Nice and simple idea but with difficulties in the implementation.

Ioannis