Smart Search Implemented H-Infinity Control Design for DAB Converter in DC Microgrid

Dual Active Bridge (DAB) converters are used in DC microgrids for electric vehicle battery interfaces due to their bidirectional power transfer, high power density, and soft-switching capability. However, there are some challenges associated with these converters. On the one hand, substantial current stress and elevated RMS current can result in substantial losses and safety concerns. On the other hand, external perturbations, disturbances, and variations in load can adversely affect the performance and stability of the system. To mitigate these issues, Triple Phase-Shift (TPS) modulation strategies have been introduced to reduce peak and RMS currents, while H∞ control methods have been developed to manage system uncertainties. An important aspect of the design of H∞ control systems is the optimization of weighting function parameters, which is complicated by the complexity of the system. This work proposes a novel solution by using a revised NSGA-II algorithm for H∞ control, which facilitates the automatic determination of controller parameters efficiently with given optimization information. The proposed control method is capable of minimizing the peak or RMS current, and provide robustness against system uncertainty simultaneously. Simulation and experimental results are presented to demonstrate the robust performance and fast response times.