基于FPGA的数字PI超声波电动机速度控制系统

摘要

针对超声波电动机速度蠕动,提出一种基于FPGA的数字PI的速度控制方案.该方案对超声波电动机输出的光电编码器方波信号进行高频插值细分,作为速度的反馈信号,通过PI运算,将其结果进行D/A转换,控制直流电压的输出,并把此直流电压作为超声波电动机驱动器的调速控制电压,构成超声波电动机速度闭环系统,从而有效解决了超声波电动机转速蠕动的问题.%A scheme of digital PI speed control based on FPGA for ultrasonic motor was proposed to solve the problem of its speed creep. The square-wave signal of photoelectric decoder was operated by high-frequency interpolatory subdivision as the speed feedback signal. The results was transformed by D/A converter through PI operation. The output DC voltage was controlled, which was considered as the speed setting voltage of ultrasonic motor drive. The closed-loop speed control of ultrasonic motor was achieved and the problem of its speed creep was solved effectively.