Tesla’s lead motor engineer (Principal Motor Designer, to use the official title), Konstantinos Laskaris, recently gave an interesting interview to Charged EVs, where he expounded in detail on the company’s direction and decision-making process to date.
There was a bit following on a question involving the use of algorithms in motor modeling that stood out to my eyes, in particular: “Beyond that, through good motor modeling, we can achieve the best optimization — which means we can achieve exotic performance without the use of exotic materials and exotic manufacturing.”
The bluntness concerning the trade-offs of different performance enhancements was also quite interesting:
So the question is, can I have everything – both high efficiency and high performance? The answer, unfortunately, is no. But you can make intelligent choices between things that are competing with each other.
This is the beauty of optimization. You can pick among all the options to get the best motor for the constraints. If we model everything properly, you can find the motor with the high performance 0-60 MPH constraint and the best possible highway efficiency.
Another example is the overall motor efficiency versus its cost. There are cases where making a motor in more expensive ways could potentially increase efficiency and buy off multiple times the cost difference by saving money on the battery, or other aspects of the car. So, if you are able to model the motor efficiency and costs accurately, you can plot it against battery cost savings. Now you can see that the optimal motor for total cost minimization is often different from the cheapest motor.
Arguably this is all “common sense,” but it’s nice to hear it stated bluntly — and it’s nice that Tesla seems to have such competent people working for it. Makes me even more impatient for the Model 3 reveal that’s fast approaching….
There’s a lot more to the interview, and it’s quite interesting, so I recommend heading over to Charged EVs to read it. (The comment section for the article is quite interesting as well, with a good discussion of the comparative merits of induction motors, like the ones Tesla uses, and permanent magnet motors.)