# Tesla Electric Motor



## HrdTsk (Jan 17, 2018)

Any info on the Tesla electric motors?

Does the Model 3 RWD electric motor have the same power / torque as the RWD Model S / Model X electric motor? Is it the same motor?

Speculating forward on the AWD Model 3..... 
Will the Model 3 AWD 2nd electric motor have the same power / torque as the AWD Model S / Model X 2nd electric motor? Will it be the same motor?

How much does LR vs SR range battery affect the power / torque of the electric motor?

Finally, any speculation on how much the AWD option will cost on the Model 3?


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## garsh (Apr 4, 2016)

It's a new motor design. It's a permanent-magnet AC motor (the S and X use AC induction motors).
It's smaller and a little more efficient than an induction motor.
Most likely, the front motor for the AWD model will be the same as the rear motor, but that's a guess.

Some previous threads talking about the Model 3's motors:

https://teslaownersonline.com/threads/epa-certification-data.4639/page-4#post-38987
https://teslaownersonline.com/threads/model-3-specs-by-tesla-from-tesla-for-tesla.5168/
https://teslaownersonline.com/threads/dc-motor-vs-ac-motor.243/

The price to go from RWD to AWD in the S used to be $5000 (back when they still offered RWD), so it will probably be similar for the 3.


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## Guest (Feb 11, 2018)

garsh said:


> It's smaller and a little more efficient than an induction motor.


Smaller but not little more efficient. IIRC, significantly more efficient (especially at the edges of load/rpm graphs). 
We are fighting in those 90's, compared to ICE 20-50% efficiencies. 2+% difference is significant 



HrdTsk said:


> Will the Model 3 AWD 2nd electric motor have the same power / torque as the AWD Model S / Model X 2nd electric motor? Will it be the same motor?


Second motor on Model 3 will also be permanent magnet motor, likely very similar to the rear motor (stator-rotor might even be the same), but with different reduction gear and likely with weaker/smaller inverter.

AWD option should cost around 4k.
*AWD will very likely NOT be available on standard range Model 3. *Ever. 
LR Model 3 will likely not be discontinued (like it happened with Model S).


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## HrdTsk (Jan 17, 2018)

Will the frunk be displaced by the motor in AWD models?

My reservation option does include an AWD model with choice of SR or LR battery for delivery late 2018.


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## garsh (Apr 4, 2016)

HrdTsk said:


> Will the frunk be displaced by the motor in AWD models?


No, the front motor is located behind the front wheel centerline, while the frunk is completely in front of the front wheel centerline.


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## KarenRei (Jul 27, 2017)

arnis said:


> AWD option should cost around 4k.
> *AWD will very likely NOT be available on standard range Model 3. *Ever.


Absolutely, fundamentally disagree with this. Just ignoring the fact that this would be leaving a huge amount of money on the table for _no good reason at all_ (lots of people getting SR would buy dual motor - myself included; range isn't hugely in demand in the Nordics, but AWD is)... you can go right now to the customization page and it *explicitly states* that AWD will be available with both SR and LR packs. And it's been this way from the beginning.

You're confusing a performance package with AWD. Yes, there is a good reason for a performance package to require LR (you need more power coming from the pack, and that's directly proportional to how many cells you have). But you do not need any more power to have AWD with normal performance.


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## John (Apr 16, 2016)

The front motor looks to have a shorter stack (the active part with rotor and stator) than the rear.
My rough guess is the the front is roughly 2/3 as powerful as the rear.


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## DNR (Feb 10, 2018)

John said:


> The front motor looks to have a shorter stack (the active part with rotor and stator) than the rear.
> My rough guess is the the front is roughly 2/3 as powerful as the rear.


I hope so but I kind of doubt it. That would put 0-60 at about 3 seconds (4.8 /(1 + 2/3)). On the other hand that probably is an actual CAD drawing of the car. The question is will they software cripple it or will they put a smaller motor in the rear.
I guess if they use different drive ratios for the front and back that could limit the acceleration too and improve efficiency a little. From what I've read here that matters less for permanent magnet motors though?
I think SR will be available for Dual Motor after they've met the demand for LRD models.


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## John (Apr 16, 2016)

DNR said:


> I hope so but I kind of doubt it. That would put 0-60 at about 3 seconds (4.8 /(1 + 2/3)). On the other hand that probably is an actual CAD drawing of the car. The question is will they software cripple it or will they put a smaller motor in the rear.
> I guess if they use different drive ratios for the front and back that could limit the acceleration too and improve efficiency a little. From what I've read here that matters less for permanent magnet motors though?
> I think SR will be available for Dual Motor after they've met the demand for LRD models.


Yep, if they add 2/3 more torque (and relatively little weight), you'd be looking at a car pushing 3 seconds.


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## KarenRei (Jul 27, 2017)

Seriously doubt the motors will be the limit on the performance package ; I fully expect the batteries to be. Plus, Tesla keeps talking about the Model 3 motor - singular - being used in a wide range of products. And we know Musk's obsession with mass production. 

I think the main thing we may be seeing in those diagrams is different gearboxes for different ratios.


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## John (Apr 16, 2016)

KarenRei said:


> Seriously doubt the motors will be the limit on the performance package ; I fully expect the batteries to be. Plus, Tesla keeps talking about the Model 3 motor - singular - being used in a wide range of products. And we know Musk's obsession with mass production.
> 
> I think the main thing we may be seeing in those diagrams is different gearboxes for different ratios.


The internal gears no doubt will be city/highway-optimized at each end (highway in front, like the other Teslas).

But regardless, we're looking at the CAD model, which I would think is pretty authoritative. The gearboxes are the ribbed part away from the motor (motor -> gearbox -> shafts) and are externally identical each end (but flipped upside down). The smooth part is the motor-y part. Both front and back have a pretty identical-looking end cap for power feed. Pinky-swear that's how these things work.

The big guess is power rating (you can't always just look at the outside of a motor and tell how it's rated). For instance, if someone said the front motor was 1/2 the output of the rear, that'd be reasonable. By pixel count it's 2/3 (16 versus 24 pixels, to be exact).

The most surprising thing to me is that in all of the "reading of the tea leaves" last year we decided the front would be a Tesla-traditional induction motor ("different architectures" explanation of delay for Dual). But these look SO similar, it's like the front is just a shorter-stack back motor...

But I would totally design it this way: mostly same parts, slightly more compact rotor and stator, exact same assembly procedure. Result: more compact motor to fit between the front wheels, geared and wound for top efficiency at highway speeds.


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## DNR (Feb 10, 2018)

Another theory is that the picture is the performance model and the regular dual motor model will have the smaller motor in the front and back. The suspense is killing me. haha. Maybe the performance model will come out first. They did say they wanted to optimize margins.


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## John (Apr 16, 2016)

DNR said:


> Another theory is that the picture is the performance model and the regular dual motor model will have the smaller motor in the front and back. The suspense is killing me. haha. Maybe the performance model will come out first. They did say they wanted to optimize margins.


But then there's this, from the Emergency Responder's guide. Rear motors look the same:


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## DNR (Feb 10, 2018)

John said:


> But then there's this, from the Emergency Responder's guide. Rear motors look the same:


That's why I'm saying that the picture could be the performance model. In the Model S they used the same rear motor in the performance models and the RWD models. In the regular dual motors they used a smaller motor.


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## John (Apr 16, 2016)

DNR said:


> That's why I'm saying that the picture could be the performance model. In the Model S they used the same rear motor in the performance models and the RWD models. In the regular dual motors they used a smaller motor.


Ah, I see what you mean. I think you're right.

So pretending along a little more:

RWD = current motor = 4.8 s
AWD = two small 2/3 motors = 3.6 s
P = one small and one big = 2.9 s


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## garsh (Apr 4, 2016)

KarenRei said:


> Seriously doubt the motors will be the limit on the performance package ; I fully expect the batteries to be.


Yep. We're already seeing that the SR battery pack causes a difference, even with what we assume to be the same rear motor.


> Plus, Tesla keeps talking about the Model 3 motor - singular - being used in a wide range of products. And we know Musk's obsession with mass production.


That doesn't necessarily preclude a shorter version of the same design.


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## Guest (Feb 13, 2018)

DNR said:


> and the regular dual motor model will have the smaller motor in the front and back.


That is the only reasonable way to have AWD with smaller battery pack - make both motors smaller than motor on M3 now.

But I'm not sure about making one more motor/inverter design...


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## Frank99 (Aug 3, 2017)

I'd be kinda interested in what the cost differential is between, say, the larger Model S RWD motor, and the Model S AWD motors. Obviously, it's enough to make it worthwhile to build a different motor, but there is so much work and so many parts that are identical between them that it seems like the cost difference would be minimal. For example, the case/rotor is a bit smaller - but I'd imagine that fabricating the case/rotor costs a lot more than the slight differences in material. There may be less copper in the motor windings in the smaller motor - but just winding and epoxying and installing them seems like it would cost a lot more than the difference in materials cost. 

Of course, my likelihood of finding out anything to satisfy this curiosity is about zero.


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## garsh (Apr 4, 2016)

garsh said:


> No, the front motor is located behind the front wheel centerline, while the frunk is completely in front of the front wheel centerline.


This video shows how the frunk area is separate from the front motor area.


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## msjulie (Feb 6, 2018)

So lookin' at the pics above, it almost looks like I could 'decide' I needed the AWD update and they could just pop a front motor in there...


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## Frank99 (Aug 3, 2017)

And run the wires that provide power to the motor - otherwise it's just dead weight.


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## garsh (Apr 4, 2016)

msjulie said:


> So lookin' at the pics above, it almost looks like I could 'decide' I needed the AWD update and they could just pop a front motor in there...





Frank99 said:


> And run the wires that provide power to the motor - otherwise it's just dead weight.


And add shafts and hubs to connect the motor to the wheels.
But the front shock and spring are in the way, so you'll need to obtain AWD-specific versions.
And that may require a bracket to mount them.
And that front motor needs to be connected to the cooling system, so those hoses will need to be added.
And the computer needs to know of that front motor's existence and control it, so add some additional wiring harnesses.

It's all doable, and I bet somebody will eventually "upgrade" their First Production 3 to all-wheel drive, but it's not going to be easy.


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## msjulie (Feb 6, 2018)

I think I need to go back to tongue-in-check school...you all took me way to serious....


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## Bokonon (Apr 13, 2017)

garsh said:


> And add shafts and hubs to connect the motor to the wheels.
> But the front shock and spring are in the way, so you'll need to obtain AWD-specific versions.


Random thought from a mechanically-challenged mind, but: might this be why SAS is "linked" to AWD? Because air suspension provides the only form-factor that will accommodate the second motor, or do so within an acceptable range of performance?

* Disclaimer: I know virtually nothing in this area, so I could very well be asking whether it's possible to bake an orange pie simply by swapping out apples for oranges.


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## CoastalCruiser (Sep 29, 2017)

arnis said:


> Smaller but not little more efficient. IIRC, significantly more efficient (especially at the edges of load/rpm graphs).


Hello @arnis. Do you happen to have a link the load/RPM graphs you referred to? Thank you.


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## John (Apr 16, 2016)

Bokonon said:


> Random thought from a mechanically-challenged mind, but: might this be why SAS is "linked" to AWD? Because air suspension provides the only form-factor that will accommodate the second motor, or do so within an acceptable range of performance?
> 
> * Disclaimer: I know virtually nothing in this area, so I could very well be asking whether it's possible to bake an orange pie simply by swapping out apples for oranges.


I dunno. Anybody know how to spot SAS versus coils?


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## Guest (Mar 2, 2018)

@CoastalCruiser 
Found a typical PM motor graph (Nissan Leaf).








Can't find specific graph for Model S's induction motor, but few examples of general specimens: 









Even without graphs, we know, that Model S/X motor overheats (not battery, not inverter) while applying heavy load for longer. This is because heat loss is gigantic (dozens of kilowatts). Model S/X motor(s) can handle around 140-160kW constant load. Partly because of cooling restriction (too much heat generated in the stator), partly because heat buildup (heat generated in the rotor).
Nissan Leaf, while having only one weak permanent magnet motor can hold 50kW easily. Because rotor doesn't overheat (5% loss) and there is hardly any problems with cooling capacity. Heat generation is at around 40kW*0,05=2kW. That is easy to handle.


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## CoastalCruiser (Sep 29, 2017)

Sweet. Thanks.


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## Tom Bodera (Aug 10, 2016)

Suspension Mounting Changes from Model S.

Notice the same Front half shaft interference issue but brackets mounting in place for AWD suspension in RWD.








RWD








AWD


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## Tom Bodera (Aug 10, 2016)

RWD S 








AWD non P model S










Performance AWD


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