Simplistic MosFET HV Shunt Regs

You go for 200V PS3 out. Alright logical. That Tx will lead to a large rectified voltage figure on PS3 input as the guys above demonstrated though. So a large drop across Q1 on PS3. That means enough W of Q1 heat and a large heatsink. Isn't there a lower voltage transformer to use ending up in say 250V DC rectified max?

The attach circuit is the power supply we have now, and intended to replace with PS3 + SSHV2 for 160vdc regulation.

230vac figure is based on the same diagram, and we can change it to much lower voltage power transformer. What about 180vac @200ma? Is that good enough? The audio circuit is drawing 50-80ma.

thx!
 

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First of all: Why V1 has only 18V of amplitude if you want to achieve 200V at the output of your filter?
The inductances should have their active resistances too instead of currents (for simulation).
The bleeder resistor is here to discharge the capacitors to a safe level in case of broken connection to the loads (in your case - to the SSHVs). Usually the time for discharging is set to less than 30 seconds, the time could be counted as t=RC, you have 75uF in total, so any value of 400kOhm or less would be suitable for the job.
 
A choke input filter approaches 1.5Vac as the DC output when current falls.
The normally assumed output of DCV = 0.9Vac ONLY applies over a narrow range of load current.
That current range determines the required inductance. This is critical.

Using a CCS fed PSU ensures a near constant current. That will allow a precise determination of an acceptable inductor.
Using the wrong inductor, or a fuse blowing and removing the load would incur a potentially damaging increase in output voltage to 167% of the design DCV.