In an Electric Motor, why does Torque increase with current and RPM with voltage? Does anyone have the theory?
Everywhere I look, I see Torque increases with current and RPM increases with voltage. I want to understand why this happens. OHM’s Law states they must go up at the same unless your changing resistance (V=IR). I was under the assumtion the “resistance” is in the motor thus can’t be changed. Please explain how you can increase voltage without changing current (and vise versa). Also how increasing voltage WON’T affect Torque and increasing current WON’T affect RPM. Nowhere I look do they give any relationship between Current and RPM, or Voltage and Torque.
Michael:
I think you misunderstand how an electric motor works. I am not sure how to explain it to you. When motors operate they generate an internal back EMF.
Below are three links for books with information on the theory of operation for electric motors.
I hope they help with your understand of how electric motor work.
Niel