为减小切换瞬间电压和频率的暂态波动,提出了基于控制器状态跟随的微电网平滑切换控制方法.进入孤岛状态后,储能装置逆变器的控制方式由PQ控制转变为V/f控制,切换前使V/f控制器随时跟随PQ控制器的输出,避免切换瞬间控制器输出状态的跳变.在DIg SILENT Power Factory软件平台建立含光伏单元和蓄电池的微电网模型,仿真微电网由并网模式转为孤岛模式运行.仿真结果表明,该方法能够有效抑制切换过程中电压和频率的波动,减小暂态过程对电网的冲击.
In order to reduce the transient fluctuation of voltage and frequency during switchover,a newswitchover method based on controller state following is proposed. When transferring to island mode,the control method for inverter of storage device changes from PQ control to V / f control. Before switchover,the output of V / f controller is always following the output of PQ controller,so that the sudden change of output is avoided at the moment of switchover. A microgrid model with photovoltaic and battery is built on DIg SILENT Power Factory simulation software,to simulate microgrid switchover from grid-connected mode to island mode.The results showthis method can effectively suppress the transient fluctuation of voltage and frequency,and reduce the influence of transient process on power grid.