3 ms·
To a layman that seems like a really small efficiency tax if you can't get your hands on the magnets for some reason.
by Rapzid 4mo ago
To a layman that seems like a really small efficiency tax if you can't get your hands on the magnets for some reason.
- handstitched 4mo agoIt'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.
- namibj 4mo agoThe 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. They've been used to great success since we had the needed power electronics to drive the electric trains of Europe.
- mcdonje 4mo agoAnother comment said they're not using brushes, so they shouldn't need more maintenance.
- _kulang 4mo agoIt’s a near-doubling of energy loss - probably a healthier way to understand it when the efficiencies are all 90%+
- Maxion 4mo agoFunnily 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.
- antonkochubey 4mo agoIn 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.
- _kulang 4mo agoThermodynamically, heat is waste energy. EVs are so efficient that scavenging isn’t practical anymore; I’m not sure the temperature gets high enough to usefully extract the heat energy for heating. ICE cars obviously produce mostly heat so getting a radiator hot enough to heat the cabin is very easy
- tbrownaw 4mo agoYou can get about 2/3 as much output power for a given amount of waste heat and cooling capacity. It's like how laptop power bricks used to be big and get hot, and now they aren't and don't.