it should be interesting to know exactly what this voltage parameter DOES effectively in the controller.
obviously, the voltage that you physically apply to the controller affects only the top speed.
the controller is able to accept any voltage up to 48v (perhaps more) and I think the controller will only adapt, depending on the voltage parameter, the PWM rate for the top speed to suit the total power this is just a guess.
the result is that if you say your max voltage is 24v, it will give you more current for a given speed.
could somebody confirm (or not) this assumption?