Design and development of the microcontroller based DC motor speed control unit

A microcontroller based DC motor control unit was developed to control the user specified speed of a DC motor. The controlling unit consists of a GMR sensor along with indigenously developed planar magnetic encoder and an embedded system consisting of hardware and software. The hardware design is based on 8-bit microcontroller consisting of a motor driving unit to drive the loads up to 4 Amps. The software algorithm was developed to ramp up the motor speed to user specified value entered through keyboard. A magnetic current sensor is used, which acts as a current limiting switch for preventive measure. The efficiency of the embedded system was verified with NI data acquisition software developed for controlling these motors and the output was observed to have deviations less than 2%.