基于故障信息自同步的有源配电网纵联保护

随着分布式电源大量接入配电网，配电网结构变为多端电源网络，解决多端电源网络保护问题最行之有效的方法是纵联保护方案。但当前配电网硬件及通信水平无法满足纵联保护对线路两侧数据进行同步采样的要求。文中提出了故障信息自同步技术，故障时刻相对被保护线路两侧是同时的，以故障时刻为时间参考点，测量线路两侧基波电流故障时刻前后两相邻相同变化趋势峰值点的时间间隔变化，进而计算得到电流相位变化方向判定值，有效克服配电网难以同步采样的困难。基于故障信息自同步技术，文中提出了新型纵联保护方案，通过比较线路两侧电流相位变化方向判定值，即可判定故障位置。仿真验证了故障信息自同步技术的准确性，新型纵联保护方案具有良好的动作特性。

The pilot protection for active distribution network based on fault information self-synchronizes

As a large number of distributed power sources are connected to the distribution network,the structure of the distribution network is changed from a feed-supply radiation network to a multi-terminal power network. The pilot protection scheme is the most effective way to solve the protection problem of distribution network with DGs. Limited to the level of distribution network hardware and communication,data on both ends of lines can''t be sampled synchronously by pilot protection. To solve the problem above,a fault information self-synchronizes technology is put forward. As the moment of fault is the same time for both ends of lines,the technology uses the moment of fault as a time reference. The measurement about the interval between two adjacent peak points of the same trend before and after the fault time is carried out,and then intervals is used to calculate the current phase changes direction,which can effectively overcome the difficulty of acquisition of the synchronous data in distribution network. Based on fault information self-synchronizes technology,the novel pilot protection determines the fault location by comparing the direction of phase change on both sides of the protected circuit. Simulation results verify the accuracy of fault information self-synchronization technology,the novel pilot protection has good operation characteristics.