PWM affects only speed or torque as well?

Help & Support Robot Parts
1

Hello all

I seached in the internet and I found 2 different answers. There are many guys who report that when they reduce the speed of their motors with PWM contoller, torque is reduced as well. Some of them say that the PWM reduces the average voltage (due to duty cycle) and thus, the current is also reduced and accordingly the torque is reduced too.

However there are many other guys who say that a PWM contoller affects only the speed of a motor ( voltage control) but the current is staying constant. Thus the PWM is NOT affecting the torque (and the current) but only the speed (and the voltage).

I’m confused ? what is really happening with the typical PWM controllers we use in modelling or project cars etc ?

1 Like
2

Hi,

You should have a look at this tutorial about DC motors and controllers from one of our suppliers, Phidgets. It provides quite a bit of details about how it all works and should give you a better understanding of what actually happens in your average DC motor when PWM voltage control is used.

Sincerely,