高渗透率微网自适应电流保护方法研究

Research on adaptive current protection method for micro-grid with high penetration

随着分布式发电(DG)渗透率的不断提高,微电网保护间的配合日趋复杂,现有保护已经难以满足需求。为此,提出一种基于智能保护中心的高渗透率微网自适应电流保护方法,利用信息共享,实时获取各线路的状态信息,有效跟踪网络拓扑结构的变化,对电流保护定值进行在线计算与调整。此外,智能保护中心可充当远程后备保护,与本地保护构成双重化保护结构,提高了微电网继电保护的可靠性。算例分析和仿真结果表明:该方法不受DG接入与系统运行方式的影响,能够实时适应微电网状态的动态变化,大大提高了微电网保护的可靠性。

With continuous improvement of DG penetration,the cooperation between protections in micro-grid becomes more and more complex,which causes that the existing protection is difficult to meet the requirements of micro-grid safe and stable operation.Aiming at solving this problem,an adaptive current protection for micro-grid with high penetration DG based on intelligent protection center was proposed in this paper.In this method,the status information of every line can be acquired in real time by utilizing information sharing.The changes of the network topology can be tracked effectively,and the protection setting value can be calculated and adjusted based on various changes of state information.In addition,the intelligent protection center can be the remote backup protection,and combined with local protection,which formed a dual protection operation mode.It can improve the reliability of the relay protection in micro-grid.Examples analyses and simulation results show that this method is not affected by the DGs connected and different system operation mode.It can adapt to the dynamic changes of micro-grid in real time,which greatly improves the reliability of micro-grid.