Switching Loss Analysis of a Three-Phase Solar Power Conditioner Using a Single-Phase PWM Control Method

This paper presents theoretical analysis and experimental verification of the switching loss in the single-phase PWM control method. The single-phase PWM control method turns on or off only one of the three phase legs in each PWM-carrier period. Thus, the method makes it possible to reduce the average switching frequency by a factor of three and to reduce the switching power loss, compared with a conventional three-phase PWM control method. Experimental results obtained by a 4-kW, 200-V setup is shown to verify the viability of the developed theory. As a result, the experimental setup exhibits a good efficiency as high as 99.2% and an acceptable total harmonic distortion (THD) as low as 4.5%.