永磁同步电机高精度转速测量技术研究

Study of high precision speed detection of PMSM

针对永磁同步电机闭环调速系统对速度反馈的要求,研究了M法、T法和M/T法电机测速的原理,采用基于增量式光电编码器的T法测速,进一步研究了光电编码器和T法在测速中的对应关系,给出了机械误差和测速干扰误差对该测速方法测速精度的影响.通过限幅滤波与分段式限速滤波相结合的方法降低传感器固有机械误差,采用低通滤波算法减小测速干扰误差.最后给出了T法测速的测量电路和算法实现.通过实验验证了测速系统克服干扰误差影响的效果,提高了测速性能.

In order to meet the demand that closed loop speed regulating system for velocity feedback in permanent magnet synchronous motor（PMSM）,the motor speed measurements of M method,T method and M/T method are studied,while T measuring speed is carried out based on incremental photoelectric encoder.The corresponding relationship of photoelectric encoder and T method in velocity measurement is further studied,and the infection of the mechanical errors and speed interference errors,the metrical precision of the speed method is presented.The method is improved to reduce natural mechanical error of the sensor by combining limited breadth filter and segmented limit speed filter,the low-pass filter is used to decrease the speed interference error.Finally,the measurement circuit and algorithm of T method are presented.The experimental results show that the speed interference error is eliminated,and the speed measurement performance is improved.