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The DIY AC EV Motor journey

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OK, So I get some flack from a guy who does not like our group efforts to custom wind AC industrial motors for use in a vehicle. He says we lack any scientific credibility, (He did have a point) and we were deluding the DIY community into thinking it could be done (even though HPEV and AC Propulsion as well as Tesla and Siemens seem to do it on a regular basis).

To date, we have done eleven rewinds (that I distinctly remember). All were done by hand and did not require any special equipment.

Our results have been a mixed bag, but in every instance (But one) they ran well, proving it is not rocket science to make your own AC EV motor at home for under $1,000, AND have a custom size not as yet offered by the manufacturing community.

Our biggest problem really seems to not be the motor, but a decent controller that is affordable, (which lets imports out).

We have taken one motor and rewound it for 30 thru 90 volts and experienced what the controller does to compensate for it.

We have changed the in-hand wire bundle sizes from 8 strands up to 24 strands. (Basically that means a group of 8 wires going many times around or a group of 24 wires going only once around) Keeping the same slot fill.

We are now utilizing a "skip slot" strategy to change the saturation point in the stator, which changes the top RPM capability by trading off some torque.

We are confident of our abilities to wind and predict the motor operation, torque and RPM, but now it is time to take the next step up to accurate data acquisition instead of vehicle performance as a measurement criteria.

So, we are just putting finishing touches on a motor Dyno. It is a quality unit and is able to record repeatable results on a P.C. This way, it will be easier to illustrate the different winding types and their effects on motor operation.

A comprehensive motor winding video is in the plan also. One that takes you through the entire process from selecting a core, to the in-car optimization routine.

If and when someone finally makes a good DIY AC controller, we will be ready to custom build a good AC motor for it.....(A challenge?)