基于旋转高频信号注入法的内置式永磁同步电机低速段转子位置检测及其误差补偿

旋转高频信号注入法注入信号较为稳定,且位置估计过程不依赖电机参数,因而十分适用于内置式永磁同步电机(IPMSM)的零、低速转子位置检测。针对传统高频信号注入法无法辨别磁极的问题,用电压方波注入法检测磁极,结合有限元软件仿真,来合理选取方波电压幅值和时长,有效缩短了磁极判断耗时。分析了滤波器和信号离散化对位置估计精度的影响,提出在低速段可用线段拟合带通滤波器中心频率处的相频特性曲线,推导所需补偿角度与电机转速的关系。在理论分析的基础上,采用基于DSP28335的样机平台进行试验,结果表明磁极判断过程稳定,耗时较短,补偿后的位置估计值相比补偿前有明显改善,调速过程中系统动态性能良好。

Rotor Position Detection of Interior Permanent Magnet Synchronous Motor Based on Rotating High Frequency Signal Injection Method and Error Compensation

Rotating high frequency signal injection method was well suited for the rotor position detection of interior permanent magnet synchronous motor in the zero and low speed range, for the stability of the injected signals form and the independence from motor parameters. The square wave voltage injection method was used to detect the magnetic pole, and the finite element simulation was performed to select the amplitude and duration of the injected square wave voltage, effectively reducing the detecting time. The effect of filters and signal discretization on the accuracy of position estimation was analyzed. It was proposed that the phasefrequency characteristic curve near the center frequency of the bandpass filter could be fitted to a line segment in the lowspeed range. The relationship between the required compensation angle and the motor rotation speed was deduced. On the basis of the theoretical analysis, experiments were carried out on the prototype platform based on DSP28335. The results showed that the magnetic pole judgment process was stable and took a short time. The compensated position estimation was obviously improved compared with that before compensation. The dynamic performance of the system during the speed regulation process was good.