An efficiency improvement method for the TAB converter based on the minimization of fundamental reactive power

With the advantages of simple topology, voltage matching, electrical isolation, and bi-directional energy control, the Triple Active Bridge (TAB) has become an active area of exploration and research for the flexible interconnection of DC ports, such as solar energy and energy storage devices. The backflow power is substantial in the conventional dual-phase shift (DPS) control strategy of the TAB converter, resulting in an increase in the RMS current and loss in the converter. To address this problem, this paper, from a different perspective, constructs the fundamental reactive power of TAB and proposes an optimal triple-phase shift (TPS) control strategy designed to minimize the fundamental reactive power. The basic principle of the TAB converter is described, and the mathematical model of the fundamental reactive power is constructed using Fourier decomposition and phasor analysis. The expressions for fundamental reactive power at the output port are then obtained. Furthermore, the particle swarm algorithm is utilized to solve the optimal problem in a global context, and a corresponding control strategy is developed. By changing the load power, the response characteristics of the output port under the DPS control strategy and the optimization control strategy proposed in this paper are compared and analyzed. Simulation and experimental results show that the optimization control strategy proposed in this paper can effectively reduce the fundamental reactive power at the output port and improve system efficiency.