Motor mod

Mitsubishi i-MiEV Forum

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New member
Dec 15, 2023
Has anyone though of replacing the rotor magnets for stronger ones to increase low rpm torque and potentially increase range?. Now in my short research my understanding is that you loose efficiency at higher rpms but this being a city car might not be a big issue. Any thoughts or did someone try this already?
It’s an induction motor, so no magnets. The lack of torque at low speeds is all software. The motor is capable of more, but Mitsubishi limited torque at the low end for passenger comfort.
That isn't correct, just Google a motor teardown for imiev and you'll see that there are magnets.
My understanding is that motors with permanent magnets are extremely difficult to work with unless you have special equipment. Replacing the magnets is unlikely to be practical, I think.

I would also think that the motor controller firmware would have to be changed to take account of the different V/Hz constant. As above, that might well be all that you need.
I thought we had a permanent magnet (PMAC) motor. Anyway, the Pike’s Peak race car ran stock motors at much higher power levels and the inverters/ reprogramming gear was available to do so for businesses and universities at a high price, though I haven’t investigated again in the past decade. Details are in this forum…,,
I don't see why there would be a problem with firmware as it might only think you're going down hill so you require less amps for the same rpm. One other benefit might be stronger regen but I do wonder if that wouldn't be a problem as it will produce more power per rpm than stock so it might trigger faults.