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Electric motors with no rare earths

renaultgroup.com

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Re: Electric motors with no rare earths

#51

Post by XorNot »

userbinator wrote: post #38

A historical pioneer in the complex technology of electric motors without magnets Those who know the history of electric machines will find the title and verbiage very amusing. Motors with no permanent magnets were the first practical ones, and at this point wound-rotor motors are over a century old. It's worth noting that some of the biggest motors have always been designed this way, because the size of magnets requ…

Not quite true: you're also limited by the mechanical strength of your windings and core (this is the upper limit on superconducting magnets like at CERN and in fusion plants).

Re: Electric motors with no rare earths

#53

Post by Jblx2 »

XorNot wrote: post #51
userbinator wrote: post #38

A historical pioneer in the complex technology of electric motors without magnets Those who know the history of electric machines will find the title and verbiage very amusing. Motors with no permanent magnets were the first practical ones, and at this point wound-rotor motors are over a century old. It's worth noting that some of the biggest motors have always been designed this way, because the size of magnets requ…

Not quite true: you're also limited by the mechanical strength of your windings and core (this is the upper limit on superconducting magnets like at CERN and in fusion plants).

And if you also ignore iron saturation.

Re: Electric motors with no rare earths

#54

Post by drnick1 »

themafia wrote: post #46
hnav wrote: post #31

Earlier quoted context omitted.

no, but requires introduces brushes (slip-rings really) which is a wear item

Cars already have lots of wear items and a mature service industry for them. If I can reliably get at least 50k miles out of it, then I wouldn't be all that bothered, as this is not likely to be an expensive part or service.

> mature service industry for them

The car service industry is a scam, and I am glad that EVs require minimal to no servicing that cannot be easily DIY like tires and brakes.

Re: Electric motors with no rare earths

#55

Post by hnav »

themafia wrote: post #46
hnav wrote: post #31

Earlier quoted context omitted.

no, but requires introduces brushes (slip-rings really) which is a wear item

Cars already have lots of wear items and a mature service industry for them. If I can reliably get at least 50k miles out of it, then I wouldn't be all that bothered, as this is not likely to be an expensive part or service.

so apparently on the BMW i4s it requires a rear subframe drop which isn't going to be cheap (10s of hours).

Re: Electric motors with no rare earths

#56

Post by butWhathuh »

userbinator wrote: post #38

A historical pioneer in the complex technology of electric motors without magnets Those who know the history of electric machines will find the title and verbiage very amusing. Motors with no permanent magnets were the first practical ones, and at this point wound-rotor motors are over a century old. It's worth noting that some of the biggest motors have always been designed this way, because the size of magnets requ…

[flagged]

Re: Electric motors with no rare earths

#57

Post by [deleted] »

butWhathuh wrote: post #56
userbinator wrote: post #38

A historical pioneer in the complex technology of electric motors without magnets Those who know the history of electric machines will find the title and verbiage very amusing. Motors with no permanent magnets were the first practical ones, and at this point wound-rotor motors are over a century old. It's worth noting that some of the biggest motors have always been designed this way, because the size of magnets requ…

[flagged]

[deleted]

Re: Electric motors with no rare earths

#60

Post by Quarrel »

bgarbiak wrote: post #4

BMW also makes rare-earths-free motors for their EVs and - at this very moment - theirs are far more advanced. They offer almost twice the power (up to 300kW vs 160kW) and are on a 800v architecture.

Which is quite the contrast to Mercedes new axial flux electric motor, which goes all in on rare earths- the design relies on the highest end high-grade permanent magnets.

Still, presumably Mercedes ambitions are for few motors than BMW or Renault.

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