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PMAC vs induction motor for model 3

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Its funny reading page one of this post where people were like " YOU IDIOT, TESLA WOULD NEVER USE PERMANENT MAGNET MOTORS!" to reality today where they are using it.

This just goes to prove Elon will keep you on your toes!

There may have been some degree of confusion associating PM motors with DC motors... which... if they used DC motors they would need a new name ;)

Come to think of it... even a PMAC motors is a bit odd in a 'Tesla'....
 
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Strikes me the better question is

"Which is more likely: that a Tesla employee wrote this form but can't spell PERMANENT, or that this was filled in by someone at the EPA and they wrote the wrong thing?"

2017-08-07_18h43_07.png


 
Looks like I am vindicated in my prediction. For those who doubted me, now I can say "told you so!"

Now if only they put the PMAC into the Model S with a 120KWh battery pack, I wouldn't be surprised if it can do 400 EPA miles at the cost of performance, but still quite fast if it was AWD.

Just because they chose to put in a PMAC motor into the Model 3 doesn't mean they should do it for the Model S, or a least their highest performance vehicles. The power output is very different. We shall see the difference in the efficiency as the rpm's increase and torque is low... ie. high speed highway cruising.
 
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Someone claimed that these forms are filled out by government clerks, and often have errors. So, I think we need to take it with a grain of salt.

Rereading Tesla's missive on motors: Induction Versus DC Brushless Motors
is informative. Also, a video on their induction motors:

So, I have a question for the motor engineers -- is it possible that Tesla has made a combination motor, which has permanent magnets in its rotor, but also coils -- hopefully combining the advantages of both?
 
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So, I have a question for the motor engineers -- is it possible that Tesla has made a combination motor, which has permanent magnets in its rotor, but also coils -- hopefully combining the advantages of both?

Yes it should be possible, and someone on here claim to know that Tesla was going to use a hybrid approach in the Model 3. Though we don't know if that was in a single motor, or if they were going to put a PM at one end and a Induction at the other.
 
Yes it should be possible, and someone on here claim to know that Tesla was going to use a hybrid approach in the Model 3. Though we don't know if that was in a single motor, or if they were going to put a PM at one end and a Induction at the other.
Thanks. I suspect, of the top of my head, that a hybrid motor might be the worst of both worlds (danger of demagnetizing the permanent-magnets), but who knows? Certainly, using a PM and a induction in two separate motors seems like a win-win -- better efficiency at low speeds with the PM, and better at high speeds with the induction motor. I do believe that Tesla engineers will make an informed choice.
 
Many of the world's fastest/quickest EVs use permanent magnets... just want to throw that out there.

Yes, but at what power levels and at what volume? Formula E vehicles, for example, average 190 kW with their PMAC motors. That's less than a Model 3. But they also rarely are in low torque situations.. they're high torque or high regen almost all the time. And there just aren't that many made.
 
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From April:
Estimate The Horsepower of the P75DL
Tesla will NOT use the same motor as in the S and X.
Why would they? The Model 3 will be 20% lighter than the S, so a smaller motor will give plenty of go power along with the required efficiency.
There is also a report of a third party vendor stating they are making permanent magnet motors for the M3. SO if true this will be a major departure for Tesla. But one thing for sure is that Tesla is not afraid to challenge the current orthodoxy...even when it is their own.
Some think they will be using a new, hybrid type motor than is more efficient than a given induction or PM motor of the same size.
This is the fun stuff we get to see at the next reveal. :)

Going Electric Technology || ZERO MOTORCYCLES
 
If you say so. I seem to remember reports that the entire battery system and motor system and entertainment system of the BOLT were from LG. Could be those reports were inaccurate..
The Bolt EV motor was not "off-the-shelf from another manufacturer". The motor was custom designed specifically for the Bolt EV by GM engineers in Michigan. They wrote an SAE paper about the details of its design:

Electric Motor Design of General Motors’ Chevrolet Bolt Electric Vehicle

Also, the Bolt EV uses a custom-designed fixed gear reduction transaxle. It is not an "off-the-shelf CVT.

.
These two posts do not entirely contradict each other. LG was deeply involved in all aspect of Bolt drivetrain. Denise Gray, CEO of LG Chem Power was previously head of battery at GM, a GM lifer and graduate of K entering U née. GM Tech. The two teams were joint, and LG does produce the whole powertrain IIRC. The SAE article is by GM members but never discussed LG role.

As for 'generic CVT' that may well a question of definition. The motor for the Bolt was a derivitive of the one used in the Spark EV. Guess which company designed that one? Frankly the world of Tier One is replete with cases in which the supplier actually did most if a design credited to the vehicle manufacturer.
 
If you check out the following certification documents the MS and MX are listed as using AC Induction motors while the M3 is listed as using a 3 Phase Permanent Magnet motor:

Model 3: https://www3.epa.gov/otaq/datafiles/CSI-HTSLV00.0L13.PDF

https://www3.epa.gov/otaq/datafiles/CSI-HTSLV00.0L1S.PDF
https://www3.epa.gov/otaq/datafiles/CSI-HTSLV00.0L2SV2.PDF
https://www3.epa.gov/otaq/datafiles/CSI-HTSLV00.0L2XV3.PDF
My guess is that the obvious typographical error puts the whole notion of Tesla using permanent magnets in their motors in question. On page 3, in a section labeled "Hybrid Electric Vehicle And Fuel Cell Information" there is a line for:

Motor/Generator Type 1 | AC 3 PHASE PERMENANT MAGNET | Rated Motor/Generator Power | 192

Someone may have simply chosen the incorrect option for a drop down menu before saving the PDF file, or simply typed in the wrong information. Because 'PERMENANT' is not the correct spelling for 'permanent' at all. I suspect the 192 is kW, not horsepower. So, the mechanical equivalent of about 257.476 hp. Not the 300+ I was hoping for, considering the rating for Model S 60, but it'll do against the given competition among 'entry level luxury' vehicles.

There is also the fact that Elon Musk and JB Straubel have been rather adamant that AC Induction, and avoiding the use of any form of 'rare earth metals' in the construction of their cars is imperative, makes me feel that form is not correct. I could find no publicly accessible means of getting to those PDF files. Why are they on a 'www3' server instead of a 'www', anyway?
 
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