Simplified Fixed Frequency Phase Shift Modulation for A Novel Single-Stage Single Phase Series-Resonant AC-DC Converter

Recently, series-resonant based dual-active-bridge (SR-DAB) topology and corresponding phase-shift modulation strategies have been widely studied as a promising candidate for grid-connected bidirectional converter applications. However, the strongly coupled non-linearity between the power level and phase-shift variables makes the control very complex. This paper proposes a novel series-resonant single stage single phase AC-DC converter, along with a simplified fixed-frequency single-phase-shift (FF-SPS) modulation strategy. Two ground-connected half bridges on the AC side with parallel capacitors will clamp the switch voltage automatically during switching, results in a simple switching pattern on the primary side. On the secondary side an adaptive phase shift enables Power Factor Correction (PFC). Critical system performance includes PWM switching pattern, zero-voltage-switching (ZVS) range and switching stress for each switch are examined respectively. A novel Fast-Fourier-Transform(FFT) based modeling method is introduced to analyze the system performance. Finally, a detailed simulation result with semiconductor loss model is introduced.