A Three-Phase Voltage-Source Solar Power Conditioner Using a Single-Phase PWM Control Method

This paper presents operating performance of a three-phase solar power conditioner introducing a single-phase pulse-width modulation (PWM) method. The proposed modulation method turns on or off only one of the three-phase legs in each PWM-carrier period. Thus, the proposed method makes it possible to reduce the average switching frequency by a factor of three and to reduce the switching power loss to 1/3 or less, compared with a conventional three-phase PWM method. Experimental results obtained by a 4-kW, 200-V setup is shown to verify the operating principle and performance. As a result, the experimental setup exhibits a good efficiency as high as 98% and an acceptable total harmonic distortion (THD) as low as 4.1%.