I've noticed that most people are bolting their electric motors directly to their transmission. Why aren't they using a typical flywheel and torque converter setup between the motor and transmission? Wouldn't you be able to go faster with fewer horsepower if you could shift gears?
Hi, John - The answer is in the difference in the torque curve between the internal combustion engine and the electric car motor. If you'd like to look at a good graph, check out p. 115 of Build Your Own Electric Vehicle.
With an internal combustion engine, most of the horsepower of the engine is needed to get you from 0-45 mph. A transmission helps it get there as efficiently as possible.
With an electric motor, like the series wound DC motor that is so popular in homebuilt electric car conversions, getting from 0-45 mph is what it does best.
Since an electric car's motor is controlled by a pot box and a controller, the real challenge is to avoid losses as much as possible.
At the present time, no transmission does a better job of minimizing losses than some sort of two-step arrangement; one gear for getting moving, one gear for the freeway.
All the best, Lynne
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