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HV power supply and ZVS switching? Answered

I am slightly running out of brain power here and get the feeling I am just running around in circles.
Problem:
I want to build a HV power supply delivering 10-15KV that is driven by a ZVS circuit - basically the same I used in my Induction Heating Ible.
I also want to double the output voltage with a simple cascade.
Goal: To get the most effiency without overheating things.

Areas where my brain feels too empty from thinking:
1. I know for sure the primary of the transformer will operate at a resonant frequency but how does this affect the scendary coil, especially under load?
My small scale tests showed quite severe changes in the frequency depending on the load put onto the primary...
Also the output voltage shows "spikes" at certain frequencies, I assume this happens while both primary and secondary share some harmonic frequencies.
2. With a simple dide/capacitor cascade I would only get a DC output, to keep an AC output slightly more complex circuits are required.
How does this affect the resonant frequency of the secondary winding?
3. Considering 1 and 2, is there a simple way of keeping both the primary and the secondary coil of the transformer in resonance regardless of the load?

Discussions

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steveastrouk

Best Answer 2 years ago

3.) Add feedback !!

Load reduces Q of the resonant circuit

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Downunder35msteveastrouk

Answer 2 years ago

Was afraid someone would suggest that LOL
So you mean basically doing the switchmode approach with opto-couplers and controller chip?

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iceng

2 years ago

Sorry a load takes power away from a resonating ckt.

Eventually a variable load takes so much power that there is not enough left to resonate.

You need to make an input additive power circuit as the load increases.