Research On Cascading Failure Critical Branches And Propagation Patterns Identification Based On Simulation Data Analysis And Mining

In the past decades,cascading failures in power systems have caused several large-scale blackouts around the world,resulting in severe economic losses and threatening the stable operation of power systems.With the increasing demand of loads,the tighter interconnection between regional grids and the emergence of new energy integration,the influence factors of cascading failure blackouts are more complex,the area of outage propagation is wider,and the consequence of blackouts is more serious Therefore,it is of great significance to analyze the process of cascading failure propagation and identify critical links in propagation for the effective cascading failure mitigation.In this paper,the analysis and control of cascading failure propagation process are studied through cascading failure simulation data analysis and mining.The main research contents are as follows(1)Establish the cascading failure simulation model to obtain cascading failure data,and conduct data modeling.ADC power flow simulation model of cascading failure based on branch overload is established,which is used for obtaining cascading failure data(i.e.fault chains and system load losses).Considering time-sequence characteristic and outage causalities contained in cascading failure data,the data structure is modeled(2)Propose cascading failure critical branch identification method,evaluate the criticalness of branch in propagating outages and being influenced by other outages,and identify the critical outage propagation relationship.According to outage propagation relationship,the branches can be divided into propagation branches and vulnerable branches.Based on the improved web link analysis algorithm,the criticalness of propagation and vulnerable branches are evaluated respectively According to outage propagation relationship,the propagation correlation is studied,and similar propagation paths for different outages can be found.On this basis,combined with load loss data,the criticalness of outage propagation relationship in outage propagation process is evaluated(3)Propose the definition of cascading failure pattern(CFP),and propose cascading failure pattern identification method to identify critical CFPs.CFP can be formed by the combination of outage propagation relationships which contain outage causalities,and CFP can be further defined by considering characteristics of cascading failure data.The improved sequential pattern mining algorithm is used to mine CFPs from fault chains,and criticalness of CFPs in outage propagation process can be evaluated by further considering system load losses,so as to realize the efficient identification of the cascading failure propagation path that may cause serious blackout and critical branches.