Development of a DC Motor Speed Control System Based on PID

In the field of motion control systems, motor speed control plays a pivotal role. Various control algorithms and methods have been developed for this purpose, and one of the earliest strategies to emerge was analog control. Over time, it has evolved into a typical control structure with convenient parameter tuning capable of meeting general control requirements. This design is based on digital control algorithms, with the ST89C52 microcontroller as the control core. It generates pulse-width modulation (PWM) pulses controlled by a digital algorithm to regulate the speed of direct circuit (DC) motors. Additionally, it utilizes a photoelectric sensor to convert motor speed into pulse frequency, which is fed back to the microcontroller, thereby achieving closed-loop speed control and eliminating static speed errors.