It’s a near-doubling of energy loss - probably a healthier way to understand it when the efficiencies are all 90%+
replyFunnily enough if enough of that energy loss (heat) can be scavange, this wouldn't be nearly that bad for us living up here in the cold.
replyIn most EVs motors are watercooled, so that energy can indeed be scavenged – problem is, during low-speed driving, the heat output is not high enough to get noticeably above ambient temperature.
replyYou can get about 2/3 as much output power for a given amount of waste heat and cooling capacity.
replyIt's like how laptop power bricks used to be big and get hot, and now they aren't and don't.
It's a small difference, but if you had a choice between "more efficient AND less maintenance" and "less efficient and more maintenance" then it's easy to see why the permanent-magnet solution is preferred.
replyThe actual alternative is induction motors, which are just a bit less efficient than PMSM and otherwise basically the same. Except that the frequency fed to them isn't exactly proportional to speed.
replyThey've been used to great success since we had the needed power electronics to drive the electric trains of Europe.
Another comment said they're not using brushes, so they shouldn't need more maintenance.
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