[57Chevy]

Interesting idea, do away with rare earth magnets so vehicle price isn't tied to the commodities price and then instead of an old induction motor like Tesla, power the rotor via brushes and achieve a motor with adjustable BEMF. The extra thermal load from the rotor electromagnet is well made up by being able to turn down the magnet at light loads and at high speeds. Quite clever really. Can't wait till people start crashing these

Redirecting

amp-interestingengineering-com.cdn.ampproject.org

 

[57Chevy]

Call me a luddite or skeptic,

I'd call you a lot of things before either of those terms based on the way you interact with people here. Rude, impulsive, attention deprived... But then I also need to recognise that as part of an inclusive society we have to accept that some people don't have awareness of or control over their behavior.

The design is not new in any way, car alternators have used this principle since the 1960s. What is new is the realisation that China holds almost all of the raw materials to make magnet motors and this is a risk to productivity if China decided to change the price or availability for reasons that suit their desires. I wonder if the chip shortage has made OEMs take a harder look at their supply weaknesses and act accordingly.

What is new, and quite clever, is the holistic approach to making a drive unit that meets more than just the basic requirements of being efficient.

 

[57Chevy]

I did notice the use of commutator, which it obviously isn't. I guess their writer and editor aren't electric motor specialists.

Mahle are claiming to be developing an induction coupled system to eliminate the brushes which is basically what truck alternators have done for decades

 

[57Chevy]

After all, Renault considered the same factors and made the same decision - a decade ago - and has since switched to PM motors.

Tesla also, and also now have PM motors. I guess there is nothing new, just new reasons

The simplest reason from a DIY perspective is that magnet motors are virtually impossible to disassemble safely without a very strong jig

 

[57Chevy]

Not true

lol. Getting them out is the easy(er) part, getting them back in without gacking the sleeve or tweaking a bearing is less fun. I spent more than a bit of time making rotor extraction jigs for exactly these reasons.

 

[57Chevy]

The traditional system uses an auxiliary three-phase radial stator winding to induce current in an auxiliary three-phase radial rotor winding, which is rectified to power the rotor main rotor winding.

The ones I have seen are much simpler, just a stationary coil of wire inside the spinning claws, rather than a spinning coil of wire as part of the claws.