Big Electric Car Motor, Small Conversion

by Patrick L.
(Montreal)

BIG electric car motor, no batteries (unlicensed driver)

I started an EV conversion project with an old Lincoln SA-200 DC generator from a welding machine.
Before investing more money into it, do you think this will work? I tested the motor on 48 volt and it runs good (no load). Can I use it for regenerative braking?

Hi, Patrick -
Jim Husted from Hi-Torque Electric says:

"Way too much motor. Where do you put the batteries?
The most common mistake people tend to make is put in too SMALL a motor for their conversion; and the second most common mistake? Too LARGE a motor. It’s a little like Goldilocks; you want it just right. 8^)

Everyone is battery limited by definition, so you don’t want to carry more weight than is needed as it could be used for battery weight, or just a lighter, more economically running conversion.

As for re-gen, it’s got some nice attributes, but the most I’ve ever heard of (reliably) is about 10% recovery in energy. This would equate to 22 to 44 miles in range from a 20 to 40 mile conversion. There’s more complexity and costs to do this so each must weigh their own needs.

I would not suggest using a brushed series wound DC motor for re-gen as brush arcing will occur."

- Jim

P.S. from Lynne: About Jim Husted...

He's with a company called Hi-Torque Electric; if you've been around EV-land for long you've already heard of him; he's been building and repairing EV motors since before you were born, kid...

... and I'm thrilled to introduce him as our DC Motors and Control instructor at EV University (online). For more information, follow the link. See you in class!