Sensors & Transducers (Jun 2011)
The DC Motor Speed Controller Using AT89S52 Microcontroller to Rotate Stepper Motor Attached into Potentiometer in Variable Regulated Power Supply
Abstract
The DC motor speed controller using AT89S52 microcontroller with stepper motor attached into potentiometer in variable regulated power supply had been evaluated. The voltage across DC motor is varied using program subroutine in microcontroller. The reference speed was determined using keypad and actual speed measured using rotating disc with holes in optocoupler sensor. The actual speed in rpm was determined after running time base 1 second and substracted with reference speed. The error was used to turn right stepper motor if actual speed less than reference speed and vice versa. The number of step of stepper motor rotation in one cycle execution was varied using subroutine starting from 1 step, 3 step, 5 step and using approximation of difference value between actual speed and reference speed. It was observed that the best performance of controller was achieved if number of step of turning stepper motor was not constant but depending on the difference between actual speed and reference speed.
