Medium Voltage Ring-Bus Grid Design Employing Current-Fed, Three-Port Dual Active Bridge Converters with Average Power Flow Control

This paper introduces a coupled control strategy for a current-fed, three-port dual active bridge converter. This method can be applied to control the converter across its full operating range, which will allow the converter to control the power flow between the three DC buses in any direction. MATLAB symbolic toolbox was used to compute average power flow equations from state space equations. The average power flow equations were then used to compute valid operating points based on the desired power output. A PLECS model confirmed the accuracy of the analysis and second model simulated a back-to-back ring bus network with two converters. The resulting average power output graphs make a useful design tool for visualizing the converter capacity across its operating range.