Audisport09 said:
Mind blown, tinker aborted. Thank you. Looks like I still have a lot of research to do.
I was running under the impression that higher voltage is always faster from start to finish.
So your saying higher voltage, lower current is better for high speed cruising and lower voltage, higher current better for lower speed acceleration? Correct?
Of course, the efficient zone does start later when the motor is fed higher voltage making faster top speed. For an example, a bike set to top at 30 mph is quite efficient at 10 mph because that is a third of its speed, while a bike that does 100 mph has very poor efficiency at 10 mph.
Acceleration is a matter of power. In the case of those 2 controllers, the 72v has lower resistance mosfets and can feed higher current. Fets that are rated higher voltage are generally higher resistance, thus rated lower current.
When the ‘higher voltage-lower current’ is matching in watts the ‘lower voltage-higher current’, like 100v 50A vs 50v 100A both making 5 kw, there is little acceleration difference but there is a notable difference at the beginning of the efficiency curve, thus the higher Amps will give better torque from the start.
That is why we don’t build a 100 mph bike when we plan to ride 50. It would make it less efficient.
