一种带辅助电感的分裂绕组电流型三电平多端口变换器及其在直流微网中的应用

Multilevel Multiport DC-DC converters (MPC) offer superior voltage-blocking capability, larger step-up ratios, and increased degrees of freedom compared to traditional two-level MPC making them particularly suitable for connecting energy storage devices to DC micro grids. This paper introduces a current-fed three level triple active bridge (TAB) DC-DC converter with auxiliary inductor which uses a split winding high frequency transformer. Detailed transformer modelling has been presented and its advantages over traditional transformer has been discussed. Power flow through different ports has been analyzed using Fourier series of port voltages which remains valid over the entire range of duty cycle and phase shift angle. Effect of different variables like the duty cycle and phase shift angle on power flow and zero voltage switching (ZVS) operation has been presented. The performance of the proposed converter structure has been validated on a laboratory prototype operating at 1.6 kW power output and 100 kHz switching frequency, achieving voltage conversion from 90V to 650V. The prototype demonstrated a peak efficiency of 96.8% during forward power flow which is at least 4% more than the conventional VF TAB converter.