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Old 02-05-2021, 12:51 PM   #10 (permalink)
AeroMcAeroFace
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Quote:
Originally Posted by aerohead View Post
1) Porsche addresses the issue with a two-speed transmission.
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2) The Institute of Electrical Engineering, Karlesruhe Institute of Technology, Germany, reports that the issue of high-rpm electric motor operation and efficiency stem from divergent rpm Lorentz force, versus Reluctance force rpm optimization requirements, which Martin Doppelbauer and Patrick Winzer resolved in their laboratory R & D.
Today's 12,000 - 20,000 rpm motors may soon yield to 30,000 - rpm motors, currently under development.
Something like 49,000 member organizations of the Institute of Electric and Electronic Engineers, globally, are actively addressing this issue.
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3) Typically, in mechanical engineering, it's common to assume a constant BSFC, with respect to predictions surrounding road load hypotheticals. As a mechanical engineer you would know that.
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4) My illustration for the Cybertruck / tadpole configuration, with the exception of correcting for higher rolling resistance, isolates only the delta- road load response based upon Cd. It absolutely assumes the efficiency demonstrated by Tesla performance. And I'll make absolutely no apology on account of that. You'd suffocate on the margin of error.
1) What is the relevance to your calculations? Tesla used to use the front/rear power split to maximise efficiency as the motors had different efficiency bands, I don't know if they still do.

2)Relevance?

3)True, apart from the fact I am not an engineer

4)Assumptions of constant efficiency are perfectly adequate,(assuming you know that there is a small margin of error) we can agree there also. Thanks for clearing that up.
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