In this paper, a novel single-stage single-phase isolated bidirectional AC-DC PFC bidirectional converter is proposed for grid-tied energy storage applications. Inspired by the innovative AC side topology, the paralleled primary side half bridge capacitors, and the body diodes of MOSFETs clamp the switching point voltage up automatically, of which is followed by a simplified modulation scheme on the AC side. On the secondary side, an adaptive phase shift is employed to adjust the instant power level along the whole AC line cycle to guarantee unity power factor. A Fast-Fourier-Transform(FFT) based circuit analysis method is introduced to examine the key system performance, including PWM switching patterns, zero-voltage-switching(ZVS) along the whole AC cycle and switching currents for each switch. Finally, a detailed simulations in PLECS is demonstrated to verify the FFT based model results.
