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Old 11-27-2018, 01:55 AM   #12 (permalink)
mechman600
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Quote:
Originally Posted by Angel And The Wolf View Post
The torque falls off as the motor gains RPM. All electric motors have peak torque at stall. A continuously variable transmission, keeping the motor near stall with acceleration, would give the best acceleration.
Not true if you control peak current electronically like all EVs do. With a motor controller capping peak amps at, say, 450A (in my Electric Booger), torque remains constant from zero rpm up to the rpm where the amount of voltage required to maintain said current is equal to pack voltage. In the Electric Booger this is 4000 rpm and 68V (pack voltage sag @ high current). Electric motor current is proportional to torque.

An AC motor's huge advantage is lack of back EMF, so voltage required to maintain a set current does not rise with rpm, which allows for a massive rpm range. If you look at the torque curve on many available AC motor kits, they are flat from nearly zero to very high rpm.
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