this is a follow up to my last question. I am working on a hand crank battery charger project. My current set up is that I am using a geared nema 17 stepper motor as a generator and have a bridge rectifier on each coil. I have the both of the two rectified coils wired in parallel to get max current output. I also have a 25V 4700uf capacitor across each rectifier to stabilise the output. I then feed the rectified voltage into a buck/boost converter to step it down to 5V which is what my 18650 li-ion BMS requires.
However I notice that when I first turn the crank there is a 10V spike from the output of the buck/boost module before for about 1 second before it stabilises to 5V (slightly less under load).
My question is what is causing this and is it a problem for my BMS circuit? If so how can I avoid it? I have a feeling it’s to do with that capacitors but I don’t know for sure. Help wound be much appreciated, happy to provide more details if need be.
Thanks
Billy.
Best Answer
I think the three items will help provide some context. I think you may still be able to use the buck converter approach with a zener voltage limiting front end on your circuit.
What is the role of zener diode in this clipper circuit?
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