What’s inside an EC Apparatus brand constant voltage constant current power supply used for Electrophoresis – the separation of particles in a fluid by using an electric field.
You can get these supplies quite cheaply on ebay if you look around.
A quick reverse engineering of the circuit provides some insight into what’s happening.
en.wikipedia.org/wiki/Electrophoresis
en.wikipedia.org/wiki/IGBT
en.wikipedia.org/wiki/Snubber
Datasheets:
www.irf.com/product-info/datasheets/data/irg4ph50k.pdf
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