[BrianG]

A motor has a certain resistance. Current is determined by voltage divided by resistance. So, you increase voltage, current will increase as well.

However, motors are NOT simply resistors. They do have a baseline resistance value, but also inductive reactance, which depends on motor speed and load (and frequency). Resistance and reactance creates impedance. Increase the speed increases the impedance. Increase the load decreases the impedance.

So, you can actually keep the same current draw when going to higher voltage IF you also reduce the mechanical load by reducing gearing. Motor is doing the same amount of work, but with different voltage/current requirements.