DC motor control system based on PWM technology
Due to its good starting, braking and speed regulation performance, DC motors have been widely used in various fields such as industry and aerospace. With the development of power electronics technology, pulse width modulation (PWM) speed regulation technology has become a commonly used speed control method for DC motors, featuring high speed regulation accuracy, fast response speed, wide speed range and low power consumption. The power drive circuit with the H-bridge circuit as the driver can conveniently realize the four-quadrant operation of the DC motor, including forward rotation, forward rotation braking, reverse rotation and reverse rotation. It has been widely used in modern DC motor servo systems. .
1. DC motor PWM speed control principle
DC motor speed control can be divided into excitation control method and armature voltage control method. Excitation control is used sparingly, and armature voltage control is used in most applications. With the advancement of power electronics technology, changing the armature voltage can be achieved in a variety of ways, among which pulse width modulation (PWM) is a commonly used method of changing the armature voltage. The method is to adjust the armature voltage U of the DC motor by changing the ratio of the on-time of the motor armature voltage to the energization period (ie, the duty ratio), thereby controlling the motor speed.
