分布式智能协同和云计算相结合的配电网故障选线新方法

New Fault Line Selection for Distribution Network Based on Distributed Intelligent Collaboration and Cloud Computing

针对谐振接地系统发生单相接地故障时选线方法可靠性不高、计算量大、算法实现复杂的问题,提出了一种基于云计算的配电网分布式智能故障选线方法。首先,通过构建配电网智能故障诊断云模型,将大量数据处理与复杂选线算法实现推至“云端”;其次,在分布式智能选线系统内,利用零序电压突变量和相电压的15%作为智能单元的启动,以提高智能单元启动的可靠性、选线的速动性;然后,详细讨论了包含故障电流主要特征的特征频带,并对区域智能单元内采集的暂态零序电流做小波变换选择特征频带;再次,通过分布式智能单元之间的协同分析,将特征频带上信号的幅值和相位信息结合起来进行故障选线;最后,通过算例验证。结果表明,所提方法不受复杂故障条件的影响、通信压力小、选线准确度高,为谐振接地系统单相接地故障实现快速选线提供参考。

Aiming at the problems of low reliability,large calculation amount and complex algorithm implementation when a single-phase grounding fault occurs in the resonance grounding system,a distributed intelligent fault line selection method for distribution network based on cloud computing is proposed.First,by constructing an intelligent fault diagnosis cloud model of the distribution network,the large amount of data processing and complex line selection algorithms are pushed to the“cloud”.Second,in the distributed intelligent line selection system,the zero sequence voltage mutation and 15%of the phase voltage changes are used as the start of the intelligent unit to improve the reliability of the start of the intelligent unit and the quickness of the line selection.Then,the characteristic frequency band containing the main characteristics of the fault current is discussed in detail,and the transient zero-sequence current collected in the regional intelligent unit is transformed into wavelets to select the characteristic frequency band.Furthermore,through the collaborative analysis between the distributed intelligent units,the signal amplitude and phase information on the characteristic frequency band are combined to select the fault line.Finally,it is verified by a calculation example.The results show that the proposed method is not affected by complex fault conditions It has low communication pressure but high line selection accuracy,which provides a reference for the realization of fast line selection for single-phase grounding faults in resonance grounding systems.