Given that a car will need to run off stored power (Battery or fuel cell etc.), is it best to use the DC supply to run a DC motor, or drive a controller to run an AC motor to power the car. I'm disocunting running an AC generator as this would still need powering by an engine, which seems pointless.Which type of electric motor is most suited to powering a car and why?
I'm not sure about the other stuff but I have an idea for a throttle. Hook a potentiometer up in series with the motor, power source. Controlling it on the ground side may be better so you can have a big thick cable from the power to the motor.
For smaller cars, with a power requirement of only a few dozen kW, it is is more efficient to use DC motors. Advantages: No DC to AC conversion with associated losses needed to run the motors. Wide rpm range. Torque can be controlled either with running the four individual wheel motors in parallel, or 2x2 series or all four in series. Another torque and power control is possible with pulse width control at a frequency of several hundred Hz. For larger vehicles such as trucks with a power requirement of 1 MW or more it would be more efficient to convert the battery DC power to variable frequency three phase power. This would have the following advantages: Lighter motors for the same power. More efficient conversion of DC to var. freq. 3-ph AC power than pulse control of large DC currents
