Hi, I am working on a project where I want to reduce as much load as I can. So my idea is to figure out between what RPMs I need to run the motor to get my desired voltage. (To avoid using a charge controller and I am using it as a generator) However, I am missing key information which is figuring out the amperage? Is there a way to get a rough estimate of amperage running at a certain rpm? I have a motor rated as: 120v , 3500 rpm, 50w I want to run between 262.5rpm & 182.29rpm which will produce run at 262.5 rpm produces accounting for inefficiency ~7.2V run at 182.29 rpm produces accounting for inefficiency ~5V
Amps can be calculated by deviding volts by watts. Since you know what watts are produced reducing the rpm (roughly) you can get a rough amp measurement. https://www.rapidtables.com/convert/electric/Watt_to_Amp.html
There are too many variables. You can get an idea from the above. But still there is mass of the windings, flux of the magnets,thickness of the wires ,amount of turns per pole,rpm,number of poles.
