Sensorless Control of PMSM Based on Improved SOGI High-Frequency Pulsed Sine Wave Injection

In sensorless control of the permanent magnet synchronous motor (PMSM) based on the pulsating high-frequency voltage injection method, the traditional filter incurs a substantial phase delay when extracting the high-frequency response current to obtain the rotor position information. This phase delay significantly compromises the accuracy and efficiency of the motor control system, leading to suboptimal performance and instability issues. To tackle this problem, this paper proposes a novel rotor position detection method grounded in an improved second-order generalized integrator. This innovative structure consists of two second-order generalized integrator cascades plus an integrating link, effectively mitigating the phase delay, bolstering harmonic suppression, and enhancing the system’s dynamic performance. Simulation results using Matlab/Simulink show that this method has good stability during the motor start-up acceleration phase, and has strong carrying capacity after stabilization. The method effectively reduces the rotor position observation error, improves the observation accuracy, and exhibits better dynamic performance and anti-interference capability.