Something that is lacking with EV discussions.

The start motor example with a fixed commutation angle is simply not comparable to the sophistication found in 3-phase motors (with either PM or electrically-excited rotors) with high-frequency inverter drives that have been used widely in industry for 2-3 decades and now EVs. Every factory robot has five or more servomotor axes using the same technologies.

EV manufacturers are doing a pretty good job already optimising the efficiency and utilisation to be competitive. Motor speeds have been climbing and many are in the 15k-20k RPM range now. Many now use oil-wetted rotors and stators for cooling and lubrication rather than a coolant jacket and grease-packed sealed bearings. That also allows better mechanical integration with the gear reducer as no intermediate seals are needed.

There are still options to build DIY EVs with aftermarket controllers and motors but the focus is more on re-powering old ICE cars rather than applying cutting edge technology. It would be very hard to improve on what you can buy off the shelf today from the market leaders.

The Borg-Warner unit discussed in Weber Auto's video apparently can be purchased for such projects and I'd suggest it's a very good design.
 
The reason is the size and amount of the windings. AKA very low resistance, similar to a direct short, thanks to some inductive reactance it isn't when running. All starter motors are current hogs.
So please tell me how much HP a Tesla motor puts out? And what is its approximate size, length and diameter?
It is magnetism that is the ultimate importance for motors, again all the controller stuff is all secondary in importance.
 
The reason is the size and amount of the windings. AKA very low resistance, similar to a direct short, thanks to some inductive reactance it isn't when running. All starter motors are current hogs.
So please tell me how much HP a Tesla motor puts out? And what is its approximate size, length and diameter?
It is magnetism that is the ultimate importance for motors, again all the controller stuff is all secondary in importance.
I can’t find detailed info, but it fits within the subframe and is very compact even with the reduction gearbox/differential attached. A model 3 RWD is rated at 271hp and 310lb ft of torque according to Car and Driver.

IMG_9255.webp

How much would a typical EV car motor weigh?
The model 3 rear motor comes in at 101.6lbs/46.10kg, the Bolt EV motor weighs 113.5lbs/51.49kg.
 
I can’t find detailed info, but it fits within the subframe and is very compact even with the reduction gearbox/differential attached. A model 3 RWD is rated at 271hp and 310lb ft of torque according to Car and Driver.

View attachment 194037

The model 3 rear motor comes in at 101.6lbs/46.10kg, the Bolt EV motor weighs 113.5lbs/51.49kg.


Thank you.

I was expecting them to be heavier actually.
 
Hmm what gauge wires feed that thing? Anyone know the amp draw on that for various loads?
And what voltage do they use?
 
Recently read an article about a Tesla covering 1,000,000 miles. I think it required 8 battery changes though.
The part that really surprised me though, was that it also took 15 Motor replacements.

That's because wheel motors are way less reliable then using an electric motor where it belongs, which is in the engine bay. The wheel motors are subject to things like pothole damage, and when the bearing on that wheel motor goes, you need a new motor. That's just not going to happen if your EV is powered by a single motor not subject to the same shock. It would also help is wheel motors had individual replacable and regreaseable bearings.
 
Hmm what gauge wires feed that thing? Anyone know the amp draw on that for various loads?
And what voltage do they use?
It’ll vary depending on the vehicle and how many volts it’s designed for. Model 3 for example is running on 350V and a Porsche Taycan is 800. For say a 1,000W load the Model 3 requires 2.85A, the Porsche needs 1.25A.
 
That's because wheel motors are way less reliable then using an electric motor where it belongs, which is in the engine bay. The wheel motors are subject to things like pothole damage, and when the bearing on that wheel motor goes, you need a new motor. That's just not going to happen if your EV is powered by a single motor not subject to the same shock. It would also help is wheel motors had individual replacable and regreaseable bearings.
I was not aware that Tesla used wheel motors. All of the cut-aways I've seen appear to have them more in the center of the axle, where a differential would be.
I'd think "wheel motors" would be more outboard, like near or in the wheels.
 
The motor assemblies are beasts and no doubt could be turned up at the expense of lifespan.

Can you get more from them on your own as a project (like say building a sand rail which id love to do) - probably.

Can you monitor cool and control a giant high voltage pack and trust you own BMS to charge discharge not just safely and find a better balance than the factories - not even a chance.

This is well beyond anyone I know on these boards to begin to handle - so no you dont hear about modding EV's
 
It’ll vary depending on the vehicle and how many volts it’s designed for. Model 3 for example is running on 350V and a Porsche Taycan is 800. For say a 1,000W load the Model 3 requires 2.85A, the Porsche needs 1.25A.
So if your talking electrical power figures, 1,000 W load is not even 2 horsepower. Unless the vehicle doesn't weigh more than a small motor cycle and has next to no wind resistance it needs much more HP than that.
What is the HP figures for those vehicles at say 60mph? If a motor is designed around electrical power figures then the normal electrical calculations pertain.
 
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