DESIGN OF DIGITAL PWM SPEED SYSTEM OF DC MOTOR

A digital PWM speed control system of DC motor is proposed.The control system mainly consists of single chip controller, motor speed and current input passageway, keyboard and display module, digital PI regulators (ST, LT) and digital PWM generator. It measures motor speed and current, then calculates parameters of digital PI regulators (ST, LT) and generates digital PWM wave through P 3.4 . In addition, the main circuit of DC motor power supply is composed of a L298 IC chip and four UAA4002 IC chips. By realtime measurement and treatment of motor speed and current, realtime digital PWM control of DC motor can be realized. The system is provided with good dynamic and static properties of great practical value.