Research On Magnetic Integration And Loss Optimal Control Of Four-port Energy Router

The DC energy router is friendly for accessing multiple energy sources and achieving the comprehensive and complementary utilization of energy.The bidirectional converter is the key component in DC energy router for energy transmission between two ports.This paper studies the bidirectional four-port energy router on magnetic integration and efficiency optimization control.Firstly,the coupling characteristics of the four-port energy router are analyzed,and the inductance parameter constraints for ports power decoupling are studied.The switch equivalent circuit,inductor current and power transmission of the four-port energy router under extended phase-shift control are analyzed based on the inductance parameter constraints.The soft-switching implementation is analyzed combined with the parasitic capacitance and dead time of the switches.In order to reduce the leakage inductance and ensure the decoupling characteristics of the four-port energy router,the transformer winding structure,the magnetic integration analysis and design of the inductor are carried out and the finite element simulation verification of the transformer and inductor design are given.Secondly,the transformer loss and power device loss models of the four-port energy router are analyzed and established.By simplifying the analysis of the system loss model,the control based on optimized RMS current is determined.Combined with the characteristic analysis,the mathematical model of the RMS current is established.Taking the energy transfer characteristics and soft-switching characteristics as the constraints of equality and inequality respectively,the Lagrange extremum method is used to figure out the efficiency optimization variable that the four-port energy router achieves softswitching under the same power,while the RMS current is the smallest,reducing the loss of converter.Finally,a four-port energy router simulation model and a prototype experimental platform are built to verify the correctness of analysis and effectiveness of optimal control strategy from the perspectives of simulation and experiment.