Run system at 24 volts & take waveforms across MOSFET. Then you can extrapolate those waveforms for 310 Volts .Once i turn ON the power, the MOSFET explode. And gate driver fails too.
Actually 4n35 is slow, but I archived fast turn OFF but pulling it’s gate to emitter by 10k ohm. And i check the waveform with the oscilloscope, it is pretty well.
Here it is.
Hmmm, I'm not sure about that. At 310v Vds the impact of the charge through the drain-gate capacitor on the switching time is very different to that at 24v...Run system at 24 volts & take waveforms across MOSFET. Then you can extrapolate those waveforms for 310 Volts .
Add RC Snubbers @ 310 volts it is must.
For engineering purposes the ionisation point of air is usually taken as 1kV/cm depending on atmospheric conditions etc but many cheap/small eg 1/4W resistors are rated at 200 - 250v. Its common practice then to use a string of them to limit the voltage across any single resistor. Some more expensive types, eg Ohmite, are rated at 500V or 1kV so you could use fewer but at £1.80 ($2.50) each that's expensive. Historically the 'general rule of thumb' was 5:1 though I can't cite a specific source. So a minimum of 5 resistors to make 99Mohm. 20Mohm are hard to find so I use 10Mohm, needing 10 resistors. Does that make it clear?
Just because the probe is rated at 300V doesn't mean you should rely on that. For both these HV probes the HV end is a custom heavily insulated cable/probe. I wouldn't use a 300v tip on a 1kV circuit..
I think so, because I tested my circuit with 20ish Voltages and the waveforms were good I couldn't notice much of the issues, but once I apply 310V, boom!Hmmm, I'm not sure about that. At 310v Vds the impact of the charge through the drain-gate capacitor on the switching time is very different to that at 24v...
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by Jake Hertz