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New vehicle info....why?

New vehicle info....why?

"front motor is induction"
"Rear motor is permanent magnet"

Anyone wanna guess as to why T thought we needed this information?

Lonestar10_1999 | 2 februari 2020

It could come in handy if you find yourself as a contestant on Jeopardy

FISHEV | 2 februari 2020

"Anyone wanna guess as to why T thought we needed this information?"

PM motor is a selling point so Tesla wants to let owners and buyers know it has this feature.

gmr6415 | 2 februari 2020

As Tesla advances in technology those specifications may change over time. Rather than you trying to get through to them just to find out what motor/s you have or what chip you have, all you have to do is look on the car...same goes for resale.

RayNLA | 2 februari 2020

To free up the forum from endless debates.

KLemMer | 2 februari 2020

Isn’t that what a forum is for?

EVRider | 3 februari 2020

The Autopilot computer info is useful, since some owners don’t know if they have HW2.5 or HW3 (aka FSD Computer). Not every car produced after Tesla started using HW3 actually has HW3 installed.

kevin_rf | 3 februari 2020

I just want it to list which assembly line/tent it was produced on. To me, being able to say my car was produced in the tent would be a plus.

andy.connor.e | 3 februari 2020

Because the permanent magnet motor is more efficient, and the induction motor can be turned off to save energy when cruising on the highway as the Model S always used to do with the induction motors.

CharleyBC | 3 februari 2020

I think the biggie for adding this screen was to eliminate everyone wondering which computer they have. But then given the new screen, they thought of other interesting tidbits they could include.

bjrosen | 3 februari 2020

Why wouldn't you want to know that? I want as much info as they will give me. I wish they would add some info about battery health.

TeslaTap.com | 3 februari 2020

For me, the more info the better!

Mike UpNorth_ | 3 februari 2020

Could they ever do PM front and back? For more badassness

Mike UpNorth_ | 3 februari 2020

Or the opposite, induction for both for a cheaper slower version?

hokiegir1 | 3 februari 2020

@Mike - I *think* (but am not positive) that the S and X both had induction for both - at least, they used to, though this may have changed. The permanent magnet was new for the Model 3, if I recall correctly.

Kary993 | 3 februari 2020

Where does this new vehicle information appear? On website or in car? As I could not find it on the website.

Techy James | 3 februari 2020

@hokiegir1 You was correct prior to the Raven refresh from last year when the front motor was replaced by a PM motor over the previous Induction motor for both front and back.

Techy James | 3 februari 2020

@Kary993, in the car assuming you have the 2020.4.1 update.

Kary993 | 3 februari 2020

@Techy, yes I do thanks!

creativeguy | 3 februari 2020

With all the different models (SR SR+ DM RWD P, etc) it isn't always easy to know what model it is. Seems like a simple way to prove what the particular build is.

Mike UpNorth_ | 3 februari 2020

@kary

In the car, software tab, then 'more info' or something like that.

gmr6415 | 3 februari 2020

@hokiegir1, PM motors will always have a drag to them, because they have a permanent magnet in them rather than creating the necessary magnetism with a small amount of current.

I'm pretty sure there were some Ss with a different gear ration in the front, and It's my understanding they are doing the same with the 2020 Roadster to get that 250+mph out of them.

The purpose was/is one motor/gearbox for torque and the other for efficient higher speeds. With an induction motor they can terminate the current creating the magnetism, and it will coast much with less resistance when not in use than a PM motor. Switching from one to the other would have the same result as shifting into a higher gear. I've never seen it explained how they synchronize the two while both are in use such as heavy acceleration.

I don't know that to be absolute, but it's the theory I've read of how it works.

The following isn't exactly what I was looking for, but it's close:

https://insideevs.com/news/338618/has-tesla-changed-how-it-controls-fron...

Has Tesla Changed How It Controls Front & Rear Motors For Model 3?

The theory is that the rear motor is now the “cruise” motor which is opposite to Model S.

Consider this a bit of speculative forward thinking. Tesla has not said they have changed the way they control the front and rear motors. However, they have given us a few facts that may indicate they have.

The LR AWD version of Model 3 gets the same range as the RWD version (310 miles) while Model S AWD got better range than RWD version.

The rear motor in Model 3 is a permanent magnet motor while the front motor is an induction motor. Model S had induction both front and back.

Both facts listed above are contrary to the Model S. The Model S AWD version gets better range than the RWD version. The Model S uses induction motors both front and back.

In the Model S, the front motor has a gear ratio tuned for highway driving while the rear motor has a gear ratio tuned for acceleration. The control theory in the Model S is to let the front motor do the work at cruise since its gear ratio is tuned for that and to let the rear motor freewheel (or close to it).

In general, PM motors like the rear motor in Model 3 get higher efficiency than induction motors. This is why Tesla chose a PM motor for Model 3 - to get good MPGe and range and a smaller battery required.

Therefore, it makes sense for Tesla to use the rear motor at cruise speed, rather than the front motor like in Model S. Here’s another reason: the PM motor doesn’t like to freewheel. So again, switching to the front motor and freewheeling the back does not make sense for Model 3.