TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

Q&A with Tesla’s lead motor engineer

Discussion in 'Technical' started by mspohr, Jan 31, 2016.

Tags:
  1. mspohr

    mspohr Active Member

    Joined:
    Jul 27, 2014
    Messages:
    1,790
    Location:
    California
    Charged EVs has an interesting interview with Tesla's lead motor designer. Lots of good insight into the process they use to design and optimize their electric motors. Lots of computer simulations and designing trade-offs for power and efficiency at different loads.

    Charged EVs | Qs lead motor engineer (Full Interview)
     
  2. Peter Egan

    Peter Egan Member

    Joined:
    Dec 13, 2015
    Messages:
    42
    Location:
    Artarmon, NSW, Australia
    Q&A article offers great insight . As does this interview of Sandy Munro of Munro and Associates - Check out this video https://www.youtube.com/watch?v=uDr4L6BzpP8 With the i3, BMW showed how to take mass out of a traction motor and minimise material wastage.

    The performance experienced by people in a Tesla is very much determined by the algorithms in the EV software informed by the position of the accelerator and brake pedals. With the MS and MX Tesla has optimised high initial acceleration and long cruise range. With the lower priced M3, one assumes it will offer a lower acceleration (0-60 mph in 8 seconds?), surely lower top speed (90 mph??) using just one gear. MS and MX motors have a top speed of 18,000 rpm. M3 nay only use 10,000 rpm of the possible range to avoid the low acceleration at high revs. As induction motors are cheaper than permanent magnet motors, its possible to use a larger motor and use algorithms to get the desired performance profile across the entire speed range, but not more performance. This keeps down the cost of other drivetrain components and motor cooling components. In effect, algorithms take on the role of gears on other vehicles.
     
  3. LetsGoFast

    LetsGoFast Active Member

    Joined:
    Oct 13, 2014
    Messages:
    1,342
    Location:
    Virginia
    Good find, I thought the article was quite interesting.
     
  4. emir-t

    emir-t Member

    Joined:
    Oct 28, 2013
    Messages:
    200
    Location:
    Istanbul
    I don't think 0-60mph of the base M3 would be 8 seconds. Even a regular 85D is better than the old P85+ and both Chevy Bolt and i3 have <8 second acceleration. Also 90mph top speed is a definite no go for the European market.
     
  5. Peter Egan

    Peter Egan Member

    Joined:
    Dec 13, 2015
    Messages:
    42
    Location:
    Artarmon, NSW, Australia
    Some number to put vehicle acceleration in perspective:
    1 m/s.s typical max acceleration for a train = 0-60 mph time of 26.9 seconds
    9.8066 m/s.s standard gravity = 0-60 mph time of 2.74 seconds
    13.41 m/s.s 0-60 mph time of 2 seconds
    8.94 m/s.s 0-60 mph time of 3 sec
    6.71 m/s.s 0-60 mph time of 4 sec
    5.36 m/s.s 0-60 mph time of 5 sec
    4.47 m/s.s 0-60 mph time of 6 sec
    3.83 m/s.s 0-60 mph time of 7 sec
    3.35 m/s.s 0-60 mph time of 8 sec
    2.98 m/s.s 0-60 mph time of 9 sec
    2.68 m/s.s 0-60 mph time of 10 sec
    I would think that 3 m/s.s (~10 ft/s.s) is plenty of acceleration for everyday use.
     
  6. 30seconds

    30seconds Active Member

    Joined:
    Feb 28, 2013
    Messages:
    1,136
    Location:
    SF
    Although you may be right with regards to actual use, I believe the market perception of a car with 8.5sec 0-60mph time and top speed of 90mph would be of a very, very unattractive car. Plus no need for such stunted figures based on the capabilities of an EV.

    Elon has been very clear that 1.) the Model 3 should be extremely compelling as a car (not just an EV) and 2.) the BMW 3-series is what he is aiming at.
     

Share This Page