A Ripple Suppression Method Based Differential Spilt Capacitors for Two-stage Single-phase Inverter

This paper proposes an advanced ripple suppression scheme by controlling the bus voltage complementary with the dual active bridge (DAB) converters under extended phase shift (EPS) control without uncontrollable intervals. The existing differentiated capacitance design is based on the DAB converter under single phase shift (SPS) control, which has a limitation in parameter optimization. Meanwhile, to minimize the current stress of the DAB converters, an optimization method is designed, which considers the fluctuation of output voltage for accurate parameter selection. At the same time, this method achieves zero voltage soft (ZVS) in the DAB converters. The input-parallel output-series (IPOS) structure is adopted as the main circuit. Simulation results are provided to verify the effectiveness of the proposed scheme.