High Speed switch

[DRDC]

Hello, I am experimenting with electromagnets and need a high speed switch. I plan to pulse
300µH coils with high voltage (400-600V) at 400 Hz. I need to switch the coil from the power supply to a capacitive load between pulses. Any ideas? It is the back EMF (flyback) that is switched to the capacitive load.

 

[dougy83]

A diode perhaps? Or a IGBT with gate-drive-transformer? An SCR could probably be used quite effectively too.

 

[crutschow]

If you can be more specific about the switching sequence between the power supply and the capacitor, such as showing the circuit with just simple switches, we can perhaps give you more detailed help.

 

[simon.says]

use 555 maybe ?

 

[dr pepper]

Sounds like a flyback smps circuit, take a look at some schematics.

 

[simonbramble]

Have a look at this guide (below). As stated above, this sounds like a flyback. Are you stuck with 300uH? You might need to change this inductance depending on the switching speed and the current you need:
http://www.simonbramble.co.uk/dc_dc_converter_design/flyback_converter/flyback_converter_design.htm

This can also be modelled in LTSpice. You'll need a Schottky diode for its high speed

 

[DRDC]

Thanks for the input. Work in progress and presently on hold.