Improved Sensorless Control of IPMSM Drives Using Complex Bandpass Filter and Pseudolinear Enhanced PLL

The high-frequency (HF) rotating signal injection method has been widely applied in sensorless control of interior permanent magnet synchronous machine (IPMSM). However, the signal demodulation process is intricate and produces an undesired phase delay. Meanwhile, the conventional HF rotating voltage signal injection method also has the problem of deteriorated dynamic performance and poor robustness due to the PI phase-locked loop (PI-PLL), which cannot realize high-precision industrial control. Therefore, this paper proposes an improved scheme that adopts complex bandpass filter (CBF) to extract position information without phase shift. Furthermore, pseudolinear enhanced phase-locked loop (PL-EPLL) is employed to facilitate the optimization of dynamic response and robustness. MATLAB simulation results demonstrate the effectiveness of the proposed scheme.