DC/AC Stage Parameters Design Method for Dual-Mode Control DC/DC-DC/AC Converter System

Recently, a DC/DC–DC/AC converter system using dual-mode control to increase efficiency has been actively studied by many researchers. Due to the similar maximum voltage and current stress of switches for dual-mode control and traditional two-stage control, the same switches and switching frequency are chosen in the existing literature. However, under dual-mode control, the DC/AC stage switches discontinuously operate at high frequency, and the amplitude of the sinusoidal pulse width modulation (SPWM)wave is lower than that under traditional two-stage control. Thus, there is an issue that the selected switches have excessive performance when using dual-mode control. The DC/AC stage parameters, including switching frequency and the LC filter, are unreasonable. To solve that issue, this article proposes a new DC/AC stage parameter design method for dual-mode control the DC/DC–DC/AC converter system. The proposed method makes an overall design of the switching frequency, inductor, and capacitor. The switching frequency is increased on 100 kHz with slight influence of total loss and efficiency. The LC filter for the dual-mode control DC/DC–DC/AC converter system is diminished by more than 50% in a 1 kW case, which reduces the weight, volume, and cost of the converter system. The calculation and experimental results based on a 1 kW prototype verify the validity of the proposed method.