Sensorless Control of PMSM Based on Low-Frequency Current Signal Injection in the Direct Axis at Low and Zero Speed
A novel sensorless control method of permanent magnet synchronous motor (PMSM) based on low frequency (LF) current signal injection is proposed in this paper. A LF sinusoidal current signal is superimposed into the estimated d-axis, and the corresponding voltage response and current response are detected to estimate the rotor speed and the rotor position. This method doesn't rely on the non-ideal features but just the fundamental model of PMSM. As a result, the introduced method can be applied to not only IPMSM, but also to SPMSM. Theoretical analysis and simulation results are carried out. The simulation results indicate that the rotor position and speed can be obtained exactly at low and zero speed. The approach ensures good dynamic and static performances, and can realize accurate position servo control.
Xudong Wang, Baoyu Xu and Shaobo Zhong
Y. D. Li et al., "Sensorless Control of PMSM Based on Low-Frequency Current Signal Injection in the Direct Axis at Low and Zero Speed", Applied Mechanics and Materials, Vols. 143-144, pp. 103-107, 2012