Distribution System Reliability Evaluation Based On The Fault Incidence Matrix

The distribution system has a direct impact on the customers’ reliability.Therefore,evaluating the distribution system reliability is an important task in both system design and daily operation.In this dissertation,the following research work is carried out around the reliability evaluation of the distribution system:1)A fast analytical reliability evaluation method for the distribution system based on the fault incidence matrix(FIM)is proposed.Though simple matrix algebra and boolean operation of the fault incidence matrixes,the explicit analytic calculation of the system reliability index is realized,which avoids the repetitive network search in the traditional reliability evaluation and saves the calculation time.In addition,the analytical expression of the reliability index in the matrix form can clearly show the impact of various equipment faults on the downtime of loads,which is convenient for the reliability sensitivity analysis and the vulnerability location.2)The sensitivity calculation method for the factors affecting the system reliability is proposed.Influencing factors are divided into two categories,one is the quantifiable parameters and the other is the network structure parameters.The explicit sensitivity calculation methods are helpful to quickly locate the weak links that affect the reliability most,and provide numerical reference for the subsequent reliability promotion strategy optimization.3)Two reliability improvement optimization methods for the distribution system are presented.One is the joint optimization method for the network segment switches and tie lines.The other is the condition-based maintenance strategy optimization method for the distribution equipment.In the network segment switches and tie lines optimization,the 0-1 integer programming model is constructed,and the global optimal solution can be obtained quickly.In the optimization of the condition-based maintenance strategy for the distribution equipment,a state transition model with multiple deterioration states is established,which can flexibly simulate the deterioration process of the equipment during the operation and the influence of the maintenance behavior on the equipment condition.The optimal maintenance strategy can be easily arranged according to the reliability sensitivity value.