Approx circuit of DC-51 motor speed controller (D6 and D8 are the wrong way around, and there may be more errors). And the more I looked at the circuit, the more I liked the speed controller. Update ...

The load allowed the DC-51 motor speed controller current limit preset to be adjusted. As the control was working right down one end (max is 4A and the motor max is 0.9A), and is very light in action ...

This paper presents a DC motor speed controlling technique under varying load condition. The linear system model of separately excited DC motor with Torque-variation is designed using PID controller.

The DC motor speed control project is intended to manage the pace of a DC motor by means of an 8051 sequence micro-controller. The pace of DC motor is straightforwardly relative to the voltage ...

But not correctly, the motor is powered from the 5V supply which is only good for low speed/load. Also, this trick will not work when powering from 12V. Report comment ...