Due to the continuous expansion of grid-connected renewable energy sources (RESs), the local-based methods of islanding detection are facing new challenges. We propose a communication-based detection method based on topology graph path query that can achieve improved results. This method uses existing communication technology and intelligent electronic devices (IEDs) in distribution networks to construct a distributed islanding information system. The bidirectional breadth first search (B-BFS) algorithm is used to conduct an offline path accessibility query to establish the decision islanding path (DIP) database. Then the method can quickly obtain results of islanding detection from online verification when the state of the line changes. On this basis, according to the topological structure and operation characteristics of the distribution network, we propose to use the Dijkstra algorithm based on closed-loop constraints to query the shortest path and select appropriate tie switch. This can achieve the goal of preventing islands by maintaining connectivity through synchronous switch operations. The proposed method has been verified on testing systems, and the results show that: (1) The distributed islanding information system has outstanding performance in solving islanding problems; (2) The proposed detection method has a convincing real-time performance; (3) The method of islanding prevention can fundamentally avoid the emergence of unplanned islands and their subsequent negative effects.

中文翻译：

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一种基于配电网拓扑图路径查询的孤岛检测与预防方法

由于并网可再生能源（RES）的不断扩展，基于本地的孤岛检测方法正面临新的挑战。我们提出了一种基于拓扑图路径查询的基于通信的检测方法，可以实现改进的结果。该方法利用现有的通信技术和配电网中的智能电子设备（IED）构建分布式孤岛信息系统。采用双向广度优先搜索（B-BFS）算法进行离线路径可达性查询，建立决策孤岛路径（DIP）数据库。这样当线路状态发生变化时，该方法可以通过在线验证快速获得孤岛检测结果。在此基础上，根据配电网的拓扑结构和运行特点，我们建议使用基于闭环约束的 Dijkstra 算法来查询最短路径并选择合适的联络开关。这样可以通过同步切换操作来保持连通性，从而达到防止孤岛的目的。该方法在测试系统上得到了验证，结果表明：（1）分布式孤岛信息系统在解决孤岛问题方面表现突出；(2) 所提出的检测方法具有令人信服的实时性；(3)孤岛预防的方法可以从根本上避免无规划孤岛的出现及其带来的负面影响。这样可以通过同步切换操作来保持连通性，从而达到防止孤岛的目的。该方法在测试系统上得到了验证，结果表明：（1）分布式孤岛信息系统在解决孤岛问题方面表现突出；(2) 所提出的检测方法具有令人信服的实时性；(3)孤岛预防的方法可以从根本上避免无规划孤岛的出现及其带来的负面影响。这样可以通过同步切换操作来保持连通性，从而达到防止孤岛的目的。该方法在测试系统上得到了验证，结果表明：（1）分布式孤岛信息系统在解决孤岛问题方面表现突出；(2) 所提出的检测方法具有令人信服的实时性；(3)孤岛预防的方法可以从根本上避免无规划孤岛的出现及其带来的负面影响。