On 2009-01-11 13:02:45 -0800, John Larkin
said:

Where to begin?

The gate driver is seriously wimpy, unbypasses zener 12-volt thing,
weak opto pullup and weaker passive pulldown. Slow edges make for high
dissipation. You need a serious gate driver, like an LM5112 or some
such.

Is the transformer saturating? The slow gate drive may contribute.

Why such a tiny post-rectifier filter cap?
I tried a 35uF 400 V cap. Still same results.
What's the operating frequency and pulse width?
The frequency is variable between 90HZ and 2kH. The pulse width is 50%

Why use a transformer at all?
The transformer provides a higher voltage and lower current which is
ideal for this type of electrolysis.
What's it all for, anyhow? Electrolysis is absurdly inefficient at
high voltages.

John


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