A Novel DC Distribution Network with Multi-Level Bus Voltages and Its Energy Management System Design

摘要

A DC distribution network (DDN) with multi-level bus voltages is proposed to satisfy various DC load requirements. In the proposed DDN, a special multi-port DC transformer (MDCT) with the symmetrical CLLC resonant structure is employed for load-side voltage matching and galvanic isolation of different bus voltages. The MDCT is actually a three-port integration power converter which can construct three different bus voltages via only one power converter, and hence effectively reducing the multiple reverse conversions and improving the distribution efficiency. In addition, the power dispatch scheme of the energy management system (EMS) of the proposed DDN is also designed for transmitting the power within the battery, Photovoltaic (PV) energy and DDN bidirectionally. Finally, a SiC-based experimental prototype of the proposed DDN is established. Both the proposed DDN and EMS have been verified via experimental results.