Soft Starting Algorithm to minimize the transient inductor current and transient capacitor voltage in series resonant Dual Active Bridge Converter

Abstract

Bidirectional Dual-Active bridge (DAB) DC-DC converter is one of the emerging technologies to be used in Electric vehicle charging and renewable energy application like solar cell, fuel cell etc., where stepping up/down of DC voltage is required. As DAB is operated at higher switching frequency switching loss is very high. By using resonant converter topologies of DAB soft switching is achieved and switching losses are reduced but starting current through inductor and starting voltage across capacitor is very high. In this paper, design and modelling of 207/48 V,3000 W bidirectional DC/DC DAB Series Resonant Converter is done; open loop soft starting algorithm is used for starting in LC type series resonant converter DAB and CLLC type series resonant converter DAB to reduce the high transient currents through resonant inductor and high transient voltage across resonant capacitor, comparison of peak currents and steady state currents are made.