含多种分布式电源的微网动态仿真

Dynamical Simulation on MicroGrid with Different Types of Distributed Generations

通过算例仿真研究了不同分布式电源配置方案下低压微网从并网模式向孤网模式转换的动态运行特性,获得了分布式电源的功率、微网电压和频率的变化规律。如果选择微型燃气轮机作为微网的功率支撑手段,在微网从并网向孤网过渡过程中,系统频率波动较大,且部分分布式电源有可能在低频保护动作下与电网隔离,不利于微网的稳定运行;增加储能设备后,储能设备对于微网的稳定运行可发挥重要的作用。采用下垂控制策略的蓄电池在微网孤岛运行时可以快速为系统提供有功、无功支撑,有效抑制了由于燃气轮机动态响应速度慢引起的电压和频率偏差。

The dynamical characteristics of a low voltage MicroGrid from grid-connected mode to islanded mode with different distributed generation （DG） configuration schemes are analyzed by using simulation method, and the corresponding changing laws of each DG＇ s power, voltage and frequency of MicroGrid are obtained. When micro-turbine-based synchronous generators are used as the main power support, the frequency of MicroGrid fluctuates greatly, and some DGs are disconnected from the grid by the low frequency relays, which is not beneficial to stable operation of the MicroGrid. After increasing storage devices, the storage devices play an important role in MicroGrid control, and the inverter of battery using droop control could provide fast power support for the islanded MicroGrid, and can damp the voltage and frequency fluctuations caused by the slow dynamical response of gas turbine efficiently.