含电动汽车充电站的多端直流微电网研究

为未来大规模能源互联网的形成以及多种新能源的接入提供技术支撑，设计直流微电网的拓扑结构，提出了一种四端口环网的直流电网拓扑结构，实现交流电网、储能单元、直流负荷、风力发电和光伏发电与直流电网的互联。首先研究了交流电网与直流电网的接口方式和相关技术参数，提出了光伏发电、风力发电和储能单元等接口的技术配置。其次，研究了整个直流微电网的启停时序，设计了直流电网的接线方式、电压等级和容量，最后基于MATLAB Simulink平台搭建了直流园区系统仿真模型，然后对典型工况进行了仿真分析：（1）储能单元由放电到能量为零；（2）储能单元由充电到能量充满；（3）VSC1变换器功率反转；（4）负荷跳变；（5）储能单元由放电到充电。这些工况基本包涵了直流微电网可能出现的运行状态，对直流微电网的运行管理有较高的参考价值。

Research on multi-terminal DC micro grid with an electric vehicle charging station

It provides technical support for the future large-scale energy Internet formation and the access of various new energy sources, the topology structure of DC micro grid is designed, this paper proposes a four port ring DC grid topology, realization of AC power grid, the energy storage unit, DC load, wind power and photovoltaic power and DC power grid interconnection. Firstly, the interface mode and related technical parameters for AC power grid and DC power grid are studied, and the technical configuration of the interface such as photovoltaic power generation, wind power generation and energy storage unit is proposed. Secondly, the start-stop timing sequence of the whole DC micro grid is studied, the DC power grid connection mode , the voltage level and capacity is designed, Finally, the simulation model of DC park system is built based on MATLAB Simulink platform, and then the typical working conditions are simulated and analyzed: (1) the energy storage unit by the discharge to the point of zero energy; (2) the energy storage unit is charged to full energy; (3) power reversal of VSC1 converter; (4) load jump; (5) the energy storage unit is discharged to charge. These conditions basically contain the possible running state of DC micro grid, which has a higher reference value for the operation and management of DC micro grid.