Analysis of high frequency current at the sampling instant of SPMSM Based on High Frequency signal Injection method

摘要

This paper presents the influence factors of the high frequency current at the sampling instant based on the high frequency square-wave-type voltage injection method. Due to the use of SVPWM control strategy, the mathematical model of the surface-mounted permanent magnet synchronous motor (SPMSM) under the high frequency square-wave-type voltage injection method is established. Further, it can be deduced that the high frequency current at the sampling instant is affected by the amplitude of the injection voltage, DC-link voltage, switching period, estimated rotor position and motor parameters. Through changing these variables, the high frequency current at the sampling instant can be increased to guarantee the higher signal to noise ratio and the accuracy of the position tracking. Finally, the analysis are verified by simulation results.