An Equivalent Circuit Method for Modeling and Simulation of Dual Active Bridge Converter Based Marine Distribution System

Abstract

The dual active bridge (DAB) converter is a core component for various types of power conversions in marine distribution systems. Real-time simulation and hardware-in-the-loop (HIL) testing is helpful for validating the complex control of the DAB based shipboard electrical systems. Due to high operating frequencies of the transformer in DAB converters, the full detailed or average DAB models are not suitable for real-time simulation that requires very small time-steps (a few microseconds to sub-microseconds). In this paper, a DAB model using an equivalent circuit method is proposed for real-time simulation. The equivalent circuit of the DAB converter is represented by mathematical equations, which can be implemented in CPUs or field-programmable gate array (FPGA) and solved in parallel to achieve real-time performance. The proposed modeling method can be applied to different types of power converters that adopt DABs for the dc-dc conversion stage. The accuracy of the model is validated by comparison with the detailed model built in Simscape Power Systems (SPS) Specialized Technology.