Model 3 motor

[jcal0820]

Should have found this out earlier; the Model 3 uses a permanent magnet motor, for the RWD versions. I actually thought the entire Tesla lineup had this type of motor, but apparently the Model S and X have the induction style motor. Based on my (limited) research, the permanent magnet motors are supposed to be much more durable than the induction version, which I believe have fluids that will eventually degrade. Confirming, is the permanent magnet setup motors like the one in the RWD Model 3 the preferred, and more reliable motor over the induction counterpart? I ask because I plan on keeping my Model 3 til the wheels come off.

 

[Gavyne]

Yup, here let Tesla engineer explain this:

“It’s well known that permanent magnet machines have the benefit of pre-excitation from the magnets, and therefore you have some efficiency benefit for that. Induction machines have perfect flux regulation and therefore you can optimize your efficiency. Both make sense for variable-speed drive single-gear transmission as the drive units of the cars.

So, as you know, our Model 3 has a permanent magnet machine now. This is because for the specification of the performance and efficiency, the permanent magnet machine better solved our cost minimization function, and it was optimal for the range and performance target.

Quantitatively, the difference is what drives the future of the machine, and it’s a tradeoff between motor cost, range and battery cost that is determining which technology will be used in the future.”

 

[sreams]

Should have found this out earlier; the Model 3 uses a permanent magnet motor, for the RWD versions. I actually thought the entire Tesla lineup had this type of motor, but apparently the Model S and X have the induction style motor. Based on my (limited) research, the permanent magnet motors are supposed to be much more durable than the induction version, which I believe have fluids that will eventually degrade. Confirming, is the permanent magnet setup motors like the one in the RWD Model 3 the preferred, and more reliable motor over the induction counterpart? I ask because I plan on keeping my Model 3 til the wheels come off.

Slight correction... *all* Model 3s (not just RWD models) have a PMSRM (permanent magnet switched reluctance motor) in the rear. The front motor in the AWD Model 3s is AC induction... which is the same type of motor used in all Model S/X cars both front and rear.

 

[BrandonLive]

Normally when people say “permanent magnet motor” they mean a standard permanent magnet synchronous motor like in the Bolt. The model 3 rear motor apparently uses a new kind (for EVs) called a switched reluctance motor. From what I’ve read this requires a much smaller amount of rare earth magnetic material, and is cheaper and more efficient than the AC induction motors used on the S and X (and the smaller Model 3 front motor for AWD variants).

 

[NeverFollow]

Yup, here let Tesla engineer explain this:

“It’s well known that permanent magnet machines have the benefit of pre-excitation from the magnets, and therefore you have some efficiency benefit for that. Induction machines have perfect flux regulation and therefore you can optimize your efficiency. Both make sense for variable-speed drive single-gear transmission as the drive units of the cars.

So, as you know, our Model 3 has a permanent magnet machine now. This is because for the specification of the performance and efficiency, the permanent magnet machine better solved our cost minimization function, and it was optimal for the range and performance target.

Quantitatively, the difference is what drives the future of the machine, and it’s a tradeoff between motor cost, range and battery cost that is determining which technology will be used in the future.”

I guess, it will be used also for the Semi truck.

 

[ilg]

And, since nobody has mentioned it yet, I'll add that there are NO FLUIDS in either type of motor.

 

[jcal0820]

And, since nobody has mentioned it yet, I'll add that there are NO FLUIDS in either type of motor.

Either for the permanent magnet or AC induction variants?

 

[ilg]

Either for the permanent magnet or AC induction variants?

Correct. That is, unless you're talking about the coolant. Is that what you were referring to?

 

[jcal0820]

No, for the motor itself. Both being sealed, I was under the impression that AC induction motors typically used lubrication oil

 

[Feathermerchan]

So you think your box fan, air compressor, and home/window air conditioner indoor and outdoor fans use oil?

 

[jdcollins5]

There is an oil filter mounted on the motor gearbox. There is no maintenance schedule to change this filter. It is supposed to have been tested to a million miles.

From a tear down video, there is also a coolant loop that goes through the motor/gearbox.

 

[Feathermerchan]

Right the oil is for the gearbox. Not the motor.

 

[jcal0820]

Overall, is the permanent magnet motor more durable/reliable than induction motors, as claimed on press releases?

 

[lolder]

Probably no significant difference.

 

[jcal0820]

Well, at least it's rated for a million miles

 

[cdeleo]

There is an oil filter mounted on the motor gearbox. There is no maintenance schedule to change this filter. It is supposed to have been tested to a million miles.

From a tear down video, there is also a coolant loop that goes through the motor/gearbox.

This oil filter is one of the areas of concern for me. I live in an area of the US that uses heavily road salt. I have seen from my experience as a tech at a local repair shop (while in high school) that with traditional can style oil filters that were neglected and not changed would rust out pretty badly. Maybe tesla has better paint on theirs or it's stainless, but something I will be keeping an eye on during tire rotations.

 

[NeverFollow]

Don't the electric engine is used for heating the car cabin?

Even if the car is not moving, power is sent to the engine to generate heat?

 

[Feathermerchan]

Can you see the oil filter? I think it may be covered by all the trim underneath.

To create heat, power is sent to the motor in such a way to create no torque.

 

[lolder]

In the Model 3, power can be sent to the motor/electronics to heat the battery but not the cabin.

 

[SD_MDL3]

Has it been confirmed that the mid-range version also uses this same motor?