The Research on the Triple Phase Shift Control of the Isolated Bidirectional DC-DC Converter

Dual active bridge isolated bidirectional DC-DC converters-DAB-IBDCs, with the two-way power flow ability and high frequency isolation characteristic, can interconnect the different voltage and current level sources together, and are the critical unit to couple the diverse power source such as battery, generator, super capacitor etc. The triple phase shift-TPS control includes not only the phase shift between the primary bridge and second bridge but also the inner phase shifts of one bridge legs; so the TPS control is flexible and complicated as well because of numerous parameters. This paper mainly researches the current of the leakage inductance and the output voltage and power transfer characteristics of the IBDC using the TPS control. The back flow power-BFP is the drawback of the IBDC, so the analytic relationships of the back flow power and the voltage, current of the leakage inductance are given in detail. The zero back flow power control strategies are invested as well to improve the transferring efficiency. The experiment results show that the TPS control is optimal comparing with the traditional extended phase shift -EPS and dual phase shift -DPS.