Reliability Analysis Based On Competitive Failure Of Substation System And Importance Measure Analysis

Functional dependence(FDEP)widely exists in the substation system,during the execution of work tasks,there is a close connection and information interaction between subsystems and subsystems and components of each system,and such a connection,on the one hand,improves the operating efficiency of the system and can efficiently complete the work tasks;on the other hand,it also causes the propagation failure effect when the fault occurs.If the propagation failure effect is isolated by the monitored components or subsystems,it will only cause local effect,that is,local failure.Correspondingly,if it is not isolated,it will spread to the whole subsystem or the whole system,that is,propagation failure with global effect(PFGE).The competition in time domain between the failure isolation effect of the monitoring component(or system)and the propagation failure effect of the failing component or subsystem is called the competition failure.The competition failure previously existing research in computer systems are analyzed,the main work content on this thesis,is the study of the competition in the power system failure effect,extended and improved according to the characteristics of the key of the smart grid system substation system.This work makes our results have more valuable when analysis reliability of substation system,and provide support for substation system resource allocation and maintenance decision.On the other hand,the importance measure analysis method is studied.Importance measure analysis is an important branch of reliability discipline and a key part to refer to that must be considered in the design,operation and maintenance of the system.By means of importance measure analysis,the weak links of the system can be identified,which has always been the common concern of scholars in academia and engineering designers in industry for complex systems with high reliability and long life requirements such as power system,aerospace and nuclear power plant.The reliability analysis that takes competitive failure into account can obviously improve the value of reliability analysis results,while the importance measure analysis of substation system can identify the weak links of the system and allocate manpower and material resources more reasonably.The main content and innovation points of this paper are a carried out from these two points:(1)According to the structural characteristics of substation system,take functional dependence as the breakthrough point,based on the existing related concepts of competition failure to expand,take three levels: ingle-function dependence group single-phase mission system,multi-function dependence group single-phase mission system,single-function dependence group multi--phase mission system as the research object,put forward the corresponding analysis method.Divide the components of system according to functional dependence,and then partition all situation according to the principle of full probability formula and probabilistic,study separately,and finally to integrate all the results of the analysis.Compare the reliability results of transformer substation based on competition failure with results getted by not considering failure to verify the effectiveness of this method.(2)Three levels of substation systems are modeled: single-function dependence group single-phase mission system,multi-function dependence group single-phase mission system,single-function dependence group multi--phase mission system,and then the corresponding methods are applied.For complex practical systems,it is expected that after these three levels of modeling and analysis,the final reliability results will be obtained by recursive analysis.Limited to insufficient experimental conditions and lack of actual data,as many examples of failure distribution types as possible were used to test the effectiveness of the proposed method in the analysis of calculation examples.(3)In terms of the importance measure analysis based on multi-value decision diagram,the Birmbaum importance,Griffith importance,Wu importance,and Integrated importance measure of component states based on loss of system performance(IIM)are expanded.The expanded importance can be more easily calculated by the multi-value decision diagram method,which can reduce the amount of calculation in practical engineering applications,and in fact does not change the original definition of the importance and the physical meaning of the formulas,and finally verified by an example And discussed the relationship between them.The selection of importance measure includes static indicators and dynamic indicators;life importance and reliability importance;Whether to consider the component state transition matrix,etc.,which make them have good representation.