PWM Based Automatic Closed Loop Speed Control of DC Motor

  ijett-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
© 2012 by IJETT Journal
Volume-3 Issue-2                          
Year of Publication : 2012
Authors :  Atul Kumar Dewangan, Nibbedita Chakraborty, Sashi Shukla, Vinod Yadu


Atul Kumar Dewangan, Nibbedita Chakraborty, Sashi Shukla, Vinod Yadu. "PWM Based Automatic Closed Loop Speed Control of DC Motor". International Journal of Engineering Trends and Technology (IJETT). V3(2):110-112 Mar-Apr 2012. ISSN:2231-5381. published by seventh sense research group


The electric drive systems used in many industrial applications require higher performance, reliability, variable speed due to its ease of controllability. The speed control of DC motor is very crucial in applications where precision and protection are of essence. Purpose of a motor spee d controller is to take a signal representing the required speed and to drive a motor at that speed. Microcontrollers can provide easy control of DC motor. Microcontroller based speed control system consist of electronic component, microcontroller and the LCD. In this paper, implementation of the ATmega8L microcontroller for speed control of DC motor fed by a DC chopper has been investigated. The chopper is driven by a high frequency PWM signal. Controlling the PWM duty cycle is equivalent to controlling th e motor terminal voltage, which in turn adjusts directly the motor speed. This work is a practical one and high feasibility according to economic point of view and accuracy. In this work, development of hardware and software of the close loop dc motor spee d control system have been explained and illustrated. The desired objective is to achieve a system with the constant speed at any load condition. That means motor will run at a fixed speed instead of varying with amount of load.


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DC motor, Speed control, Microcontroller, ATmega8, PWM