High-Precision Parameter Identification Method for PMSM Using PWM Signal

Permanent magnet synchronous motors (PMSM) are widely used in the most fields for their high efficiency and high-power density. The precise parameters significantly influence the feasibility, performance, and reliability for PMSM control system, so high-precision parameter identification is essential. However, existing parameter identification methods usually overlook the impact of PWM modulation on voltage signal, leading to inaccurate voltage information for identification, and consequently causes unsatisfactory identification results. The principle of error induced by PWM modulation is analyzed and elucidated in this paper. To address this issue, this paper proposed a novel multi-parameter identification method based on the PWM signal with high frequence (HF) voltage injection. By using PWM signals to extract HF voltage information, the error induced by PWM modulation can be avoided, leading to enhanced identification accuracy. Simulation results verify that the proposed method has high identification accuracy in different operation conditions.