Real-time Power Flow Decoupling of Triple-Active-Bridge Converter for DC Microgrid System Applications

Abstract

A Triple-Active-Bridge (TAB) converter is a member of the multiport converter family and due to its benefits such as high power density and efficiency, it is gaining popularity for DC microgrid developments. The conventional structure of the TAB converter has all its ports coupled, resulting in a coupled power flow system that requires decoupling for better step response and dynamic performance. In this paper, a Look-Up Table (LUT)-based decoupling matrices with Proportional Integrator (PI) control for the real-time power flow decoupling of the TAB converter in DC microgrids is proposed. Port voltage variations and constant voltage regulation are considered for the system implementation. A 2 kW TAB converter prototype operating at 50 kHz is designed and implemented to verify the feasibility and effectiveness of the proposed power flow decoupling control method. The proposed decoupling method shows 99.79%, 99.95%, 92.05%, and 99.05% of power decoupling performances according to port power variations.