1997 Club Car Golf Cart 36V resistor sytle speed controller is there any added performance by converting to a solid state speed control system what are the advantages of converting to a 48V cart?

Answer 1

The primary 'differences' are that the solid state controller uses Pulse Width Modulation (PWM) of a fairly constant voltage verses a resistive controller using BIG resistors to drop the battery voltage before sending it to the motor. At full speed running, they will have essentially the same efficiencies. However at lower speeds the resistive controller will waste quite a bit of your precious battery power in the form of heat loss which the solid state controller will not do. The PWM controller turns the voltage on and off very quickly (pulse repetition rate), but when it's off, it's full off and when it's on it's full on. Power output is controlled by how long the pulse is left on (pulse width). There will be no (or very little) power lost to heat (external to the motor). Resistive controllers drop the battery voltage over a stack of resistors to send a lower voltage to the motor to make it run slower, but in the process, all that volage the resistors drop gets lost to heat (Power lost in Watts = Voltage dropped by resistor times current through resistor.) Less loss to heat = more cruise time per charge. There is also the idea that the PWM controller will provide for smoother speed control. The range of speeds is smoothly variable over the range, while in a unit with a so called speed board and resistors, there are "steps" to the variability of speed. Advantage of going to a 48V system verses a 36V system also has to do with the Power formula of Power in Watts = Voltage x Current (amps). Think about a DC motor with a set resistance of say 0.5 Ohms. Current is V/R So 36V/0.5 = 72A 36V*72A=2592W 746W per HP So 2592/746=3.47HP. Do those same calculations using 48V and the final number is 6.17HP. If you have a motor that can actually take it without smoking, the 48V will get you to your next Golf shot much quicker. In practice, I wouldn't advise a voltage change unless you were intending to replace everything.