Analysis and design of DC distributed DC power system with modular three-port converter

A DC distributed power system (DC DPS) based on integrated and modular three-port converter (TPC) is proposed and analyzed in this paper, which is composed of several TPCs to interface multiple energy sources, storage devices and regulated voltage bus. A half-bridge three-port converter (HB-TPC) is selected as the integrated module, and several HB-TPC modules are utilized to build the DC DPS structure. The operational principles and power flow control of the individual module are firstly presented in detail. Then, the system level power management strategy is proposed to achieve power distribution of the multiple ports. A hybrid power control, current sharing control when the battery discharges and proportional power control based on ability of sources when the battery charges, is proposed and employed. The experimental results demonstrate the feasibility of the analysis on proposed control of both module level and system level.