Multi-objective Optimization Control for Input-Series Output-Parallel Dual-Active-Bridge DC-DC Converter in EER Application

For reducing backflow power and improving dynamic performance of the input-series output-parallel dual-active-bridge (ISOP-DAB) converter in the electric energy router application, a hybrid control strategy based on the extended-phase-shift (EPS) output voltage model predictive control and gradient descent algorithm (MPC-GDA) is proposed. Firstly, the backflow power models under single-phase-shift (SPS) and EPS control are established, and the output voltage state space averaging equation under EPS control is also derived. Then the output voltage model predictive control is obtained, and the gradient descent algorithm for backflow power optimization is proposed. Finally, the overall control block diagram of the ISOP-DAB based on MPC-GDA control is derived. The simulation models of ISOP-DAB under MPC-GDA and SPS control are built and compared. It is verified that the MPC-GDA control shows better dynamic response and backflow power optimization compared with the traditional SPS control.