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Comment by satiric | Hacker News Reader

Umm, Teslas do not use DC motors, I don't know where the article got that idea. I doubt they've ever used DC motors for anything more powerful than an electric seat adjuster. The Model 3 does use a permanent magnet motor, but it's an AC synchronous reluctance motor.

If you're going to make an article about electric motors in Teslas, at least make sure you get the facts about the electric motors right.

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The first line of the article should tell you what you need to know about their quality control:

> Tesla announced at its 2024 Investor Day event that it plans to bring...

If you're going to make authoritative comments about motors, you should actually get your facts correct first.

>The Model 3 does use a permanent magnet motor, but it's an AC synchronous reluctance motor.

No, synchronous reluctance motors do not use permanent magnets on their rotors. The motors that do are called "brushless DC motors". I'm not sure what the Model 3 uses, but last time I saw a cutaway, years ago, it was using an inductance motor, which is entirely different, but maybe they switched to BLDC for efficiency gains.

What is the state-of-the-art for battery-electric ships?

the power is probably MVDC from the large battery. And these are large xxMW motors.

So will we end up usong inverters anyway?

No modern high-performance motor that needs speed control uses electric power directly from a battery or the mains: it always goes through an electronic controller of some kind, which uses transistors to generate the necessary waveforms at the required voltage. Whether the motor itself is a permanent magnet motor or an inductance motor doesn't really matter; they each have strengths and weaknesses, but they both need electronic controllers.

Ah, yes you're correct, a reluctance motor isn't a permanent magnet motor. Although the Model 3 does in fact use a PMSM - Permanent Magnet Synchronous Motor, which is an AC motor. So not all permanent magnet motors are DC.

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