Hi, i want to build regenerative system in my electric scooter, i try to rectifying back emf of three phase wire and convert it with dc/dc converter then save the power in supercapacitor. But when i try this, my mosfet was broken, because the inductive spike from bldc motor, for several time it can take over 2kV for several ms in period. I try to fix this using TVS diode and varistor, but it seems useless. Anyone know how to fix this? Sorry for my english and Thankyou for your expert.
This is what i get in my scope
This is what i get in my scope