Quote:
Originally Posted by bomelia
How far can it possibly go between "fill ups"?
The cool thing should be the constant torque (1000 ft-lbs) over the intire speed range!!
But no tail pipe sounds is weird. Maybe one could record the real one and put big speakers in the rear.
Mike
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Mike,
The 1000 ft-lbs is probably the peak torque which normally occurs at 0 rpm off the line with electric motors. The torque is directly related to amperage and, just like an electric drill, the motor draws the most amperage at stall and produces the greatest torque at this time. Perfect for acceleration off the line. An electric motor naturally has an almost ideal torque curve, maintained quite well into upper rpms, though, because of actual load.
The only way that the peak torque can occur at greater than 0 rpm is if applied voltage is suddenly deliberately increased to drive more amps through the motor. As motors gain rpm, they produce a back EMF (voltage) because they are, in effect, also a generator since the armature constitutes windings turning in a magnetic field.
When an electric motor is running freely at its top rpm, the back EMF matches the front applied voltage and, theoretically no amperage flows. In reality some amperage flows because bearing and other small frictions create a slight load that almost imperceptably slows the motor which in turn creates a slight imbalance of applied-voltage vs back-EMF and, in turn, a slight amp drain. So neutral coasting draws very little or no power. Or the back EMF recharges the battery during forced coasting. Perfect for acceleration, perfect for coasting. Too bad batteries still suck.
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