This paper proposes a method to reduce the torque ripple vibration of an integrated power factor correction (PFC) converter by using the zero-phase inductance of an interior permanent magnet synchronous motor (IPMSM) when the motor is not running. When an integrated PFC converter is applied to electric vehicle (EV) chargers, it is necessary to reduce the torque oscillation of the motor caused by the charging current. In an integrated PFC converter using an IPMSM, the zero-phase current and magnetomotive force harmonics of the permanent magnet cause torque vibration. In the proposed control method, the generated torque is estimated using the back EMF table, and the phase current is controlled to cancel it. The proposed method can be used to suppress torque vibration irrespective of the mechanical angle of the rotor. The effectiveness of the proposed method is experimentally verified. Using the proposed method, the torque vibration can be suppressed by up to 91.3% as compared to that in the case of the conventional control method. Furthermore, a power factor of 99.9% is achieved under a load condition of 1 kW.

This study proposed a control method to reduce the torque ripple vibration of an integrated on-board charger using the windings of an interior permanent magnet synchronous motor (IPMSM). During a battery-charging operation, stopping the motor results in noise, as well as damage to the motor and other components from the torque vibration caused by the charging current. In the proposed control method, the generated torque was estimated using a back-electromotive force table, and the phase current was controlled to eliminate the torque. The proposed method can suppress torque vibration, irrespective of the angle of the rotor in the IPMSM. The effectiveness of the proposed method was verified experimentally, with the torque vibration suppressed by 94% compared with that of the conventional control method.