A Novel Sensorless Rotor Position Estimation Method for PMSM Based on High-Frequency Square-Wave Voltage Injection with Less Iron Loss

A novel sensorless rotor position estimation method for permanent magnet synchronous machine (PMSM) based on high-frequency square-wave (HFSW) voltage injection has been proposed in the article. Comparing with the existing HFSW voltage injection schemes, the proposed method features a unipolar injection into the estimated synchronous reference frame which can decrease the energy loss resulting from HFSW injection and hence improve the system efficiency. A practical calculation method based on the co-simulation platform integrating Matlab and finite-element analysis (FEA) tools are also proposed in the article to study and compare the energy loss resulting from different HF injection schemes. Both simulation and experimental verification are conducted in the article to verify the feasibility of the proposed strategy.