Power engineering (pulse power) question 3

[Alue]

I have a simple circuit designed to discharge a large capacitor in a short amount of time. The latch I use to discharge the energy stored in the capacitor is robust and can handle well above the amount of current and voltage I am discharging. My problem is, when I connect a short load to the output the switching device is destroyed. I think this is caused by flyback voltage (the only thing between the switch and the load is an inductor). My question is how do you protect against this without reducing the amount of energy discharged or increasing the duration of the discharge too much?

 

[Alue]

I'm sorry for my late reply. I was in error about some of my calculations, for one the inductance is MUCH lower, giving a much higher rise time, but not exceeding maximum di/dt. For simplification, once the capacitor is allowed to discharge, it creates and arc from positive to ground. So once the arcing is complete, I guess it would become an open circuit again. Would a large (and high wattage) output resistor in parallel with the output of the thyristor and ground help?
Thanks for the recommendations uwe. I will look into them.

 

[Skogsgurra]

Thanks. I did ask you "Are you sure that the inductance is 18 mH? That's a very high L"

A diagram and an explanation of what you are doing would have taken a lot of blind guessing out of this thread.

Could you, please, provide details now?

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[LionelHutz]

Now it's a circuit that disharges into an arc and posts to the SCR data sheet are disappearing? You really need to actually explain what you are doing and post a schematic...