Torque Pulsation Suppression Method for Electrolytic Capacitor-less Inverter by Load Power Compensation Using Dual Inverter

Abstract

This paper proposes a motor torque pulsation suppression method for electrolytic capacitor-less single-phase to three-phase power converter using dual inverter and open-end winding IPMSM. This system reduces the capacity of both the DC link capacitor and the additional capacitor by drastically pulsing the input voltage of a floating inverter. In the proposed system, the motor torque pulsation is suppressed by making the power supplied to the motor constant when single-phase ac power is pulsated. To realize the proposed method, this paper proposes a control method for the output voltage pulsation from the main inverter to the load motor with the floating inverter. The experimental results when using the open-end winding IPMSM as a load confirm that the motor torque pulsation is reduced by 95.5% as compared to the conventional system. Furthermore, the proposed control method achieves as input power factor of 95.4%.