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VFD DC bus input Answered

So I've heard it is possible to use a high voltage DC input with a 3 phase motor controller, but I haven't really found much info or instructions on how to modify them to be able to take a DC current. I am interested in this because I want to experiment with building an electric vehicle and a industrial motor. I bought a cheap, used VFD and a motor to experiment with, but it would be great to have some info and tips on how to go about doing this!



4 years ago

I just received the VFD in the mail and found the rectifier. Now I need a 400 DC source to test it out!

Presumably, at the front end, there will be a rectifier and diode to create high voltage DC from the usual incoming AC. Strip the bits out that do that, and you should be good to go.

Yes it's doable but you need a driver circuit that is able to power each coil in the motor one at a time in rapid succession to get the motor spinning. The RPM of the motor will be limited to how fast the driver can cycle through the coils.