Loss Modelling and Experimental Verification of A 98.8% Efficiency Bidirectional Isolated DC-DC Converter

High efficiency in power converters means less power wasted, which implies reduction in heat sink requirement, thereby small in size and less in weight. This power loss reductions in space application leads to smaller solar panels and less fuel on-board, hence reduces the spacecraft size, weight and launch cost. One of the major challenges for power converters in space application is to boost their efficiency, to reduce thermal dissipation problems. In this paper, design and implementation of an ultra-high efficiency isolated bi-directional dc-dc converter utilizing GaN devices is presented. Loss modelling of the GaN converter is also included in this paper. The converter has achieved a maximum measured efficiency of 98.8% in both directions of power flow, using the same power components. Hardware prototype of the converter along with the measured efficiency curve is also presented in this paper