基于CPLD直流无刷电机驱动系统的调速控制分析

阐述一种以复杂可编程逻辑器件(CPLD)为核心的直流无刷电机高性能模拟量驱动系统,它采用全硬件电路设计、梯形换相和PWM调速控制策略,具有更高的响应特性。针对模拟量驱动系统,推导计算4种PWM调制方式下电机的换相转矩脉动,提出一种改进的PWM调速控制策略,即根据占空比的不同切换不同的PWM调制方式来控制系统。通过MATLAB/Simulink仿真比较采用改进的PWM调速控制和传统PWM调速控制策略的电机转矩脉动值的大小,并搭建实验平台测试在不同占空比条件下采用改进的PWM调速控制策略的电机换相转矩脉动,验证改进的PWM调速控制策略的正确性。

Analysis of Speed Control Based on CPLD DC Brushless Motor Drive System

A high performance analog drive system for DC brushless motor with complex programmable logic device (CPLD) as core was described. Full hardware circuit design, trapezoidal commutation and PWM speed control strategies were adopted, so it had higher response characteristics.For the analog drive system,the commutation torque ripple of the motor under four PWM modulation methods were derived and calculated. An improved PWM speed control strategy was proposed, namely the system was controlled by switching different PWM modulation modes according to different duty cycles.The torque ripple values of the motor which was controlled by improved PWM speed control strategy and the traditional PWM speed control strategy were compared. An experimental platform was built, and the commutation torque ripple of the motor with the improved PWM speed control strategy under different duty cycles conditions was tested. The correctness of the improved PWM speed control strategy was verified.