Permanent magnet synchronous motor (PMSM) drive system without electrolytic capacitor was widely used in the field of white home appliance owing to its cost and longevity advantages. However, small film capacitor was utilized to replace the large volume electrolytic capacitor so that the DC bus voltage fluctuated with twice the frequency of AC source voltage. The inverter ouput voltage was saturated and the control performance was deteriorated when the DC bus voltage dropped near zero periodically, and the grid input current was distorted and the power factor was low. A motor torque control loop and an inverter output voltage modification method based on high power factor control were proposed, which could reduce the grid input current harmonics and meet the guideline of IEC 6100032. The effectiveness of the proposed method was verified through simulation.