Inspection of the Loss Reduction Effect of Three-Phase Inverter by Using a New Single-Phase PWM Control Method

This paper presents the loss reduction effect of a three-phase inverter using a new single-phase Pulse Width Modulation (PWM) control method. The proposed modulation method turns on or off only one of the three phase legs in one PWM-carrier period. In this method, the number of switching cycles can be reduced to one-third compared to a three-Phase modulation method. Also, the control algorithm can be simplified in comparison with a conventional single-phase modulation method. The simulation analysis was conducted to indicate the operating principle and evaluate its performance. As a result, it is confirmed that the proposed single-phase modulation method has control characteristics equal to the conventional single-phase modulation method and the switching loss can be reduced compared to the three-phase modulation method. In addition, the experimental results obtained by using a 2-kW, 100-V setup are shown to verify the operating principle and its performance. The conversion efficiency of the proposed system achieved 95.3%. Furthermore, the same effect as the conventional single-phase modulation method was also achieved.