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Yes, induction machines do draw power in order to establish a magnetic field where as PM machines get it for "free" by virtue of the magnets. Also the torque production at zero speed is almost identical in induction machines vs. PM machines, so this isn't an issue.

For EV applications one of the cool things about induction machines is that they can actually achieve higher efficiency at high speeds than a PM machine. This is because at high speeds the spinning magnets in a PM machine induce losses (so called eddy-current and hysteresis losses) which are difficult to suppress. In an induction machine you are controlling the field directly so it can be weakened at higher speeds with a control loop to directly optimize the losses vs. torque production. This means that there is a trade-off speed at which an induction machine becomes more efficient than a comparable PM machine.

To mitigate this issue in PMs some vehicle manufacturers have tried to do cool tricks like partially demagnetizing the magnets at high speeds to reduce losses, but this is very difficult to do without damaging the magnets permanently.

Motor size is approximately proportional to torque, not power, so you can imagine a small, low torque induction machine that is fast and will have better efficiencies than a corresponding PM machine. In stop and go traffic or low speed travel the PM machine typically has better efficiencies.

Personally I hope in the long run we end up with induction machines in our electric cars. 1) No safety issues with spinning magnets at high speed during an inverter failure, 2) no reliance on rare-earth materials, 3) the control of induction machines is very cool in its complexity and gives an additional degree of freedom on field flux that is only partially controllable in PM machines, and 4) induction machines have longer lifetimes as there is practically nothing to wear out aside from the bearings.



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