Understanding the Tesla Model S Performance Motor
Join me for a deep dive into the details of the 18,000 RPM performance rear motor and drive unit from a 2015-2016 Tesla Model S P90D. This drive unit is similar to the one used in the 2017-2020 P100D. The video is divided into four sections showing: 1. The motor and gears. 2. The high-performance bearings. 3. The lubrication system. and 4. The cooling system.
CORRECTIONS:
Thank you to everyone for catching my errors. There are always errors ;)
1. The Nissan Leaf ring gear is held on with 8 bolts, not 6.
2. The fluid in this drive unit is Dexron 6 transmission fluid.
3. Induction motor rotors do not have poles, just the stator. The 60 slot stator has four poles.
4. Silicon Nitride is a ceramic material.
Timeline:
0:00 Start
0:10 Introduction
1:35 Gearbox housing
2:10 Video Section 1 - Gears and Motor Rotor
2:45 The giant differential ring gear with 16-bolts!
4:20 The giant differential case bearings
4:50 The differential case speed at 250 km/h (155 mph) = 1841 RPM
5:15 MUST SEE Comparing the Tesla differential to others from a Chevrolet Bolt EV and Nissan Leaf EV
5:40 A Chevrolet Bolt EV differential ring gear with 12-bolts.
6:10 A Nissan Leaf EV differential ring gear with 8-bolts!
7:30 The Counter Shaft (Jack Shaft) with 25 pinion gear teeth. 78/25 = 3.12:1 Gear ratio from countershaft to the differential case
8:50 The countershaft speed at 250 km/h (155 mph) = 5743 RPM
9:30 The motor shaft with 25 teeth drives 78 teeth on the countershaft for another gear reduction of 78/25 = 3.12:1
10:08 The motor shaft speed at 250 km/h (155 mph) = 17,919 RPM
11:20 See all three gears in the reduction gearbox with an overall gear reduction of (78/25) x (78/25) = 9.7344:1
12:05 MUST SEE The AC Induction Motor Rotor with 74 bars
13:25 Motor specifications for power, torque, and gear ratio
15:00 MUST SEE Ceramic Bearings (Silicon Nitride) on the rotor from the SKF Group (skf.com)
16:22 MUST SEE Close up view of silicon nitride bearing
18:20 The motor rotor speed sensor reluctor wheel (tone ring)
19:22 Must SEE The rotor installed on the drive gear and the functioning gearbox
20:18 Video Section 2 - Specialized Bearings
21:21 The 60 slot four-pole stator and housing
23:05 The oil pump and how it is overdriven by the differential ring gear 23/78 = 0.2948:1 gear ratio (3.339 times faster than the ring gear)
23:55 MUST SEE The function of the oil pump (it may surprise you)
26:27 Motor shaft bearing reference speed and limiting speeds
27:30 How to run bearings at higher speeds than their limiting speeds
29:54 Video Section 3 - Lubrication
30:25 Drain and fill plug locations
30:50 Gearbox vent and inverter vents
31:05 Sport model label
31:39 MUST SEE Four different sealed areas in the drive unit
32:46 Video Section 4 - Cooling System
33:30 MUST SEE The coolant inlet port and the two paths coolant takes
33:53 Up for rotor cooling and gearbox cooling
35:03 Down for stator and inverter cooling
36:05 Coolant from the rotor moves to the gearbox heat exchanger and the outlet port
37:25 Stator temperature sensors
38:10 Coolant from the stator to the inverter coolant passages
38:28 Stator coolant temperature sensor
38:35 MUST SEE Insulated-Gate Bi-Polar Transistor (IGBT) module coolant passages and flow through gearbox passages
40:34 Inverter coolant outlet temperature sensor
40:45 The gearbox oil-to-coolant heat exchanger
41:38 Coolant outlet port to coolant pump and on-board charger module under the back seat.
41:55 Drive unit cooling system summary
43:04 IGBT inverter modules installed and inverter cover
43:40 High voltage battery cable connections and low voltage connections at the inverter
44:35 Video summary
Join us for hybrid and electric vehicle training with two online courses and in a 5-day on-campus boot camp with Professor John D. Kelly. See www.weber.edu/evtraining for more information.
Weber State University (WSU) - Automotive Technology Department - Advanced Vehicles Lab. A technical description and demonstration of the Tesla P90D Rear Drive Unit (RDU).
We teach current vehicle technologies to our automotive students at Weber State University and online. For more information visit: www.weber.edu/automotive
This video was created and edited by Professor John D. Kelly at WSU. For a full biography, see www.weber.edu/automotive/J_Kelly.html
Visit my other youtube channel kgfilm.info to see the amazing NVH app for vibration diagnosis!
Please consider a donation to the Department of Automotive Technology at Weber State University here: advancement.weber.edu/Automotive
Great video. Keep up the good work sir.
Huh... I assumed there would be way more magic in these.
I learned that with an EV, you're not totally getting away from oil.
What an amazing video! And great explanation of how it works.
Another fantastic class! You have some very fortunate students!
Impressive!
Prof. Kelly, thank you for making this video. I'm an energy systems and climate change researcher currently at Georgia Tech and I was a bit of a car nut in my younger days so it's very illuminating to me to see the EV tech broken down and explained. BTW I've stood and watched a tech rebuild the gearbox of a Jaguar XJR-9 race car and its innards didn't have anywhere near the beef of this Tesla Model S rig.
I watched this entire video, and now I feel like such a nerd. What a great feeling! Very informative,great insight. Thank you
Sucked me in for 46 minutes! Amazing information, very good content!
Very interesting , thanks.
I know this may be extremely difficult/expensive, but it would be amazing to also do a teardown of the latest 2021 Model S Plaid (1000-1100+ horsepower, 1300 torque I believe?) when it gets released. Sounds a bit strange, but perhaps we should cross our fingers that somebody crashes one, so that you can buy the motor? Maybe set up a crowdfund to buy a crashed Plaid motor or something haha. Or even better, get hold of a Rimac Concept 2 motor (2000HP) - but that'll probably be even more expensive haha XD
Thank you, professor.
can i change the wiring to go from a manual ac to a automatic ac in my kia optima 2014? anybody knows please?
A talented man, bless you.
Thank you very much for this explanation. regards from the Netherlands.
Tesla builds the best EVs on the planet.
If he had long hair he would be doc from back to the future
Another Excellent video from "WeberAuto" I think Professor Kelly must be one of the best instrutors ever. It's a delight to view & listen to these videos. [Please Also check out www_autotec_no , a very good contribution to instruction , Arendal Norway ]
Thank you, Mr. John. This explanation is excellent and it helped us a lot
The Nissan Leaf had 8 bolts, professor !!!
Absolutely one of the best explanation videos, on any subject, that I have ever seen. Thank you very much.
I just started working as a software engineer at an automotive transmission remanufacturer and this is absolutely perfect! I knew a little and now I know a little more. Thanks for the details and taking time to make these videos.
It is interesting to me that they are using ball bearings instead of roller bearings, I was taught that roller bearings are stronger, interesting how technology has changed.
Hopefully video platforms like YT will be referenced many, many years from now in perpetuity. BC it will take generations to fix our educational institution from the contempt of teachers and unions who are now showing us who they really are, fakes who hate America. Not all of course but seemingly the majority of the institution.
Cleaning a dirty Model 3 Motor/Drive unit.? Dry ice blasting is the key to cleaning parts without destroying the finishes, coatings, etc. The dry ice pellets turn from a solid to gas upon contacting that’s resting on the surface-without taking off anything that wasn’t originally there. The pellets aren’t removing the surface grime; the pressure of the gas is. The PSI adjustability is pretty impressive. For example, it can remove the ink from a business card without harming the cardstock. It can even remove the “M” on an M&M without damaging the colored coating.
Next time use paint stripper to help the cleaning process. Or oven cleaner
Mosy practical approach to understand this. Thank you so much. Great work
So is the difference between large induction motors of the product and 90d besides the software then?..TIA
Excellent and informative. One point, silicon nitride is, in fact, a ceramic material.
@WeberAuto Appreciate your courtesy. Thanks
Thank you, yes, I was wrong
try to disassemble the new Model S Plaid +
I hope to someday
Loved the video long time awaiting.
Thank you very much
Is that just a crummy open differential ( one wheel don't drive) in the Tesla? That should be a torque splitting or friction plate 'posi-drive' of some sort. So disappointing.
It uses the vehicle brakes as the friction plates of a Posi-drive. It works very well. Thanks for watching
Primitive overrated US shit.
Thanks for watching
wow
@WeberAuto i am tempted to convert my 1983 F100 short bed truck. it has 300 CID inline six cylinder engine and three speed manual transmission. still thinking of a dc motor low budget low speed short range project.
Thanks for watching
I personally do not like that certain bearing "have no external lubirication/ no external cooling" ....what do I know? Okay granted I dont "know" shit...I'm just saying "I dont LIKE it!" lol....Because IF I personally spend a SHIT TON of money? And driving like I DO drive? (balls to the Fing WALL?) I just do NOT want to get STUCK out of warranty with a LUNCHED car that is now NOT even worth repair....ya know?....IF I buy one of these? i TOTALLY intend to explore it's touted abilities and WILL be BEYOND miffed IF the hype was BS....just saying....ya know?
BTW I am NOT saying Elon Musk is the type asshole that would claim his product could actually achieve a spec it never COULD while simply betting that only a tiny fraction of buyers would ever even test it??? And just be willing to cover up the BS with warranty payout for the tiny few that DID test it?? ? I would HATE such a person FOREVER and devote myself to running them into the GROUND as scumbag liars.....just saying....
I wanted to know the gear ratios they use and stayed for the whole video. So much great information, you've earned my subscription
In Germany we have highways where there is no limit 🙂🤭 still the Tesla's aren't speeding...
Thank you so very much for sharing. God Bless you sir.
Next presentation; Complete Forensic Breakdown of each Rare Earth mineral mined from the ground to the overall creation to this electric vehicle. I tire of the words Self Sustainable used in every persuasive forum we see. Just the use of fire alone cancels out the entire range of sustainable as petroleum coal natural gas can never be eliminated. Myth.
It is great video I found it very educational , appreciate your effort and time in making these videos, just a quick note: if you knew the max frequency of the inverter and the the max motor speed , which we already knew, then you would be ably to find the number of the pole of the motor .
I counted 8 on the leaf.
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Thanks for sharing these “deep dives.” It’s fascinating to compare and contrast the engineering, design, and manufacturing details implemented for the various EV offerings. Naturally, there are different design goals among the different EVs, but seeing the differences in implementation between this Tesla component and what you’ve shown in the Bolt, for example, speaks to levels of elegance, robustness, and performance that can really help a consumer make a better purchase decision, based on their needs. I think both approaches show sophistication equal to, or superior to the other, each in their own way. I also find it interesting that many of us have seen ICE production evolve over decades, and have grown in our understanding and comfort in repairing/maintaining those vehicles. The relatively rapid rollout of ICE-competitive EVs has suddenly brought vehicles to the market that are familiar in basic functionality (and for some component systems), but that require serious re-education to catch up to the level of, or different technology that’s present. We haven’t “grown up” with EVs like we have with ICEs. Heck, I’m afraid to do much to our Bolt for fear of not following proper deactivation/activation sequences (Thanks to your videos. No, I really mean thanks.). These cars seem as much an electrical power distribution system as automobile. I’m seriously considering your on-line courses and workshop to gain a better understanding, if not actual ability to service/repair EVs, as a tinkerer/owner. Keep up the good work and your positive, “breezy” style. Any references you (or anyone else) can suggest for a deeper, yet understandable, dive into the electrical power systems’ theory and implementation, including inverters, frequency control, regeneration and switching?
Is there a comparison of the number of moving parts of ICE and Performance motor? Very informative; amazing and creative engineering!
The nissan leaf diff has 8 bolts, not 6!
yes and WHY does he never apologize I wonder??? WTF??
I love detailed tear-downs and explanations like these! Please keep them coming!
I remember as a young boy being fascinated by a display in the front window of an industrial machinery supply store in the center of Ludwigshafen Germany. This display, by SKF, consisted of a 6-foot high tower that had an elevator that transported a number of steel-bearing balls up to the top of the tower. Each was maybe a little larger than a Ping Pong ball. The balls then dropped off the tower to the floor below onto an angled thick round steel plate, where they then turned 90 degrees, jumped onto another angled steel base, turned 90 degrees again, and landed in a hopper to be transported back up to the top of the tower, in a continuous loop. I am not surprised that those Swedes can build bearings that can pretty much do anything.
Swedes? I thought this motor was built in Fremont CA
Lose the mic
Thanks for watching
My great mentor taught me of one thing of you like something for example eating piece of bread not just try to like it but to know how it make.
Good advice
Ludicrous Speed!
Fun stuff
Turbo encabulator. :)
kgfilm.info/net/video/k5max4HWl4Wpq58
kgfilm.info/net/video/opZnq27eh35kdps
... monastically spaced bearings to prevent side fumbling and provide increased duractance while reducing sinusoidal depleneration.
But, of course
Wow, so explanatory. Thanks boss keep doing a great job
Thank you
Great Tech - I wish I had found your Channel a long time ago - great info. 5 Star Chanel!!
Thank you very much
The left canoe hopefully film because ellipse eventually fool in a nosy face. fanatical, raspy geography
This is fascinating, I’ve seen the teardowns of the Model 3 and Y from Munro Associates, though they obviously keep a fair bit of information for themselves to sell to potential clients, so seeing this for the Model S Performance motor is really great! Liked and subbed.
Does inverter cover has seal O-ring or sealing compоund? On first sight, it looks like there is no water resist. Thanks for video, it is pleasure to watch it, as always
I was looking this kind of VDO for a week. Finally this one help cleared out my doubts Thanks so much.
Bought and driven by suckers.
what is the model of that car elevator @7:05?
@WeberAuto I meant the elevator, not The car, sorry if I worded it wrong
2018 Tesla Model S P100D
I don't know how there are still people insisting on EV's being simpler and maintenance free. Please watch this and understand it.
How do they vary the speed of the 3 phase AC motor? Does the voltage or current input change? What is the maximum input 3 phase voltage going to the motor from the inverter? Is the 3 phase input motor voltage constant?
Variable frequency changes the speed. Output voltage is approximately battery voltage. Of course that voltage slowly drops over time
Fantastic Video and Explanation ( Right at the end of the video - you refer to High Voltage - in electrical engineering that is considered greater than 240Volts - which is doubtful - I think you are meaning High Current capacity cabling rather than High Voltage. I would be interested to know what is the actual voltage being provided to the motor - thank you )
@L MVC I do not know why it burned
@WeberAuto Thank you - I'm amazed that it is 400 Volts - I was referring to British Wiring Regulations when I said over 240 volts. Have you got any information / best guess about what caused the fire in the vehicle ?
Thank you very much. The applied voltage is close to 400V with a fully charged battery. The U.S. federal government defines automotive high voltage as anything above 30V AC or 60V DC. It also required orange-colored wire insulation for those voltages. See Federal Motor Vehicle Safety Standard (FMVSS) 305 www.ecfr.gov/cgi-bin/text-idx?SID=a38f3920b0634a03f94e50338cdee23c&mc=true&node=pt49.6.571&rgn=div5#se49.6.571_1305
Unlike ICE engines, electric motors are simpler and easier to build. This is where Tesla has zero advantage as others will catch up and surpass Tesla, relegating the brand to a footnote in automotive history.
There is a lot of development in electric motors going on. The motor in this video is old technology compared to the model three motors. To say Tesla has zero advantage is quite bold without evidence. Upon what facts are you basing that statement?
Battery technology, however, is complex. This is where the cutting edge breakthroughs are happening, not in the motor.
So what might be the downside to slightly smaller roller elements (balls) in the high speed bearing? Lesser life span and / or more shaft rattle? Great presentation and reveal of this wonderfully complex powertrain. Weird to get this in a disposable product with a limited life span. Who is going to work on it when it’s ten years old or more. Parts availability? A lot of unique parts and seals!
Lower life span will cause massive parts failures as they tilt and rub on parts they should not. There are already shops rebuilding these units in California. Search the comments for motor repair.
Germans get to 250km/h daily.
@WeberAuto I made a post 4 years ago explaining how Model S cooling system works. Here: teslamotorsclub.com/tmc/threads/tesla-thermal-management-system-explanation.88055/ No heat scavanging into the cabin on older versions without Octovalve.
Awesome!
That was excellent !
Thank you
Simplified to perfection 👌i didn't know now i do ! Much appreciated 👍 Uk
Glad it helped
Congratulations the best mechanical explanation I've ever seen !!! Every particular of the motor has been shown in big detail !! Well done !!!
Thank you very much!
Non-lubricated bearings on the motor shaft at 18,000 rpm?! WOW I am impressed and also leary, lol! Seems later you mentioned these 2 bearings are lubricated internally, had to be!
I showed a white paste type grease inside the bearing seal, that is all it has. Incredible SKF technology
If didnt know better, in my opinion, your seeing alien tec.
LOL, Maybe!
I watched this whole video till the end, before I knew nothing about the technology that goes into these cars. Very professional and educational video!! thank you !! I will subscribe and watch more ! Keep up the good work!!
Much appreciated!
Informative content Professor. Thanks for teaching me something today. I think I'll have a look at the Bolt videos now.
Thank you
Something new for youtube, a really great video, that is interesting and informative to even shade tree mechanics like myself. Thanks for the video.
Glad you enjoyed it!
0:55 I suggest blasting this smoked pork with dry ice or walnut shells. Saves a lot of time and nerves. :-)
@WeberAuto I have to thank you for your wonderful work! "Danke schön" to say it in John Henry Weber's words. Is there a possibility to donate to your YT channel? Best regards from Germany (Some hours south of Weber's home town Hamburg and owning a Model 3 😁)
Good idea, thank you
Amazing job, absolutely love that this information is becoming readily available to the average idiot like me.
Thank you
The gear mounted on the electric motor, is usually called a Pinion Gear, which is usually a small spur gear. The Pinion Gear drives the Counter Gear, Which is usually a large spur gear. The Counter Gear is directly connected with another Pinion Gear, which drives another Counter Gear that is connected to the Differential. Most people call the Counter Gear that is connected to the differential a "Differential Gear".
@WeberAuto Quite welcome. 😁 btw, most differentials use helical cut gears, ie. "at an angle", but they are technically still pinion and counter gears. Also, "pinion" literally has it's roots in the word "small", though I forget what language it was from - Thus "Big and Small gears". I think there's a wikipedia on it, and everything.
Thank you for the information
As a doctor, I really suggest you to workout / somehow reduce your weight. Your obesity is affecting your breathing. As for the video, thank you for sharing a quality video on EV motor.
Thank you for your kind words
Hi, I'm still confused about the placement of the rotor with respect to the stator. Are you saying that the rotor is allowed to move up and down (along the axis of rotation) when assembled?
@T Legend The front motor rotor is spring-loaded and so are the model 3 motor rotors
@WeberAuto WOW, that must be a huge investment on cycle time. I thought they would preload it some how with a spring. Thanks for the updated answer.
They use selective shims between the outer bearing race and the housing
@WeberAuto So how would they address the tolerances from one unit to the next? On one shaft, there must some play from one bearing shoulder to the other bearing shoulder, right?
Thank you
I enjoyed every minute of it great trade for our youth to learn certain levels of it should be taught in high school remember back in the day we had pulpwood harvesting auto mechanics brick Masonry and wood works we had quite a bit to pick and choose from we need to get back to it we respected each other and work together those were the great days make America great again
Glad you enjoyed it, thanks for watching
I want to see the new PM assisted Tesla rotor please. Another great breakdown of really clean old parts. Glad I'm not paying for specimen clean-up labor and waste disposal. Great student free labor?
Coming soon. Paid student labor
But how many changes did they make in the last 4 years?
I do not know
I count 8 books on the Leafs gear.
Yes, I was wrong
I don’t understand why anyone thumbs down this video. This channel is easily one of the most professional automotive channel on KGfilm. Thank you professor for making such high quality educational videos!
Thank you very much
Wow! you got this down, really enjoyed it, those bearings fail, $$$ and the whole drive unit gets scrapped, i think those bearings are shrinked / press fit,
Glad you enjoyed it
That was fun - 46 minutes just flew by. Looking forward to your video about the Model 3 motor.
Thank you, coming soon
Excellent post. Very well taught.
Thank you kindly!
I worry that Weber might be short of tool cabinets. Sheesh!
LOL, I do need more! Thanks for noticing
who the damn is disliking this video lol
Thank you
Yes, I make mistakes and I also correct them in the top pined comment in the comments.Careless accuracy? I suspect you know better than that.
Maybe someone that sees him holding up a Leaf ring gear saying and captioning that it has 6 bolts when you can clearly see at 6:20 that it has 8 bolts. Makes you wonder what other areas he is careless in accuracy.
Professor, I was really hoping to get details on the Amps and Voltage being switched by the IGBTs. It's pretty impressive. How do they limit the RF interference from the fast switching speeds of such a high current/voltage? Is this why there isn't an AM radio in the Tesla (???). Of course i'm an EECS geek so I was really impressed with this 3 phase motor without a permanent magnet. The electro mechanical aspects are fascinating, since it's where theory meets the road. Getting all the heat out of a 60 lb rotator that is suspended in air spinning at near 20,000 rpm is just crazy. I used to joke with my wife that there is no oil to change in her Tesla, so why do they have periodic maintenance. Now I take it all back.
@WeberAuto thanks
The voltage is about 384V with a fully charged battery. The wide-open throttle current in ludicrous mode to the rear motor/inverter is close to 1300 Amps and another 600 Amps to the front motor/inverter. It uses a 2000 Amp pyro-technique fuse inside the battery pack to protect the system. All the high voltage cables use shielded wire. It is an amazing motor. The model 3 motor and inverters are even more technologically advanced. Thanks for watching.
Fascinating!, thanks for sharing this interesting and informative video
Glad you enjoyed it!
The best tutorial video I have ever watched on youtube! Very well made and comprehensible! Thank you Prof. Kelly!
Wow, thank you!
Gran video, los que nos gustan las maquinas siempre aprendemos con ellos. Gracias
Thank you
And this is why I dislike this addition to speed. All this over-engineering is a contradiction to an EV. I'm not impressed that you can go 3 times the speed limit.
@WeberAuto I understand that but I still think many people can't handle this type of power and speed. Just look at the number of deaths due to street racing.
In Germany, 250km/h is legal on some roads. Here is the USA In Utah and Texas you can drive 80 mph on certain freeways. It is a big world out there
Great job enjoyed the video 👍🏻
Glad you enjoyed it
A one speed gear reduction unit is correctly called a transmission because it is responsible to transmit the input power to the output drive, shifting gears is optional, it’s a gear transmission rather than chain transmission found in other vehicles but nevertheless a transmission ....
Thanks for the information. Most EV manufacturers still call it a gear reduction unit. This is possibly to reduce confusion with consumers who may expect it to shift if it is called a transmission.
🌈🇺🇳27:30
Thanks for watching
Where did the fire start, in the motor, in the battery or at it’s connection to the motor assembly, or somewhere else?
I do not know
Why is he laughing at the size of the bearings? Because they stupidly or wisely made them super strong to handle 550 hp from a standing start?
I was laughing in awe and the super strong large size of the bearings required to handle the incredible torque of the electric motor.
i think because they seem comically large, but he does understand why
I am puzzled. At about 17:25 you state that the motor bearings do NOT receive external lubrication and then at 26:00 you say the opposite????
Sorry for the confusion. The two bearings on the motors shaft are not externally lubricated. The motor is connected to a separate shaft with two more bearings that do receive external lubrication from the oil pump. Thanks for watching