Adaptive-ESO-based torque ripple suppression method for PMSM under single-phase open-circuit fault

This study presents an adaptive extended state observer (AESO) based sliding mode control method for PMSM under single-phase open-circuit fault. By analyzing the harmonic states of PMSM model during fault operation, the production principle of torque ripple is summarized. Then, an AESO is proposed to estimate the harmonic states caused by negative components and the 3rd harmonic component in current. Due to the salient features of proposed AESO, an appropriate 2nd harmonic compensation is added to conventional sliding mode control law. Then, the harmonics in current and torque ripple can be suppressed. A smooth torque and speed can be guaranteed under single-phase open-circuit fault conditions. Finally, numerous comparative simulation results are provided to verify the effectiveness of proposed method.