Analysis Of Vulnerability Assessment And Reconfiguration In Self-healing Distribution Networks

The intelligent self-healing power grid brings a sense of hope into the power system security. It can rapidly predict, detect and respond to any possible accidents. Based on the distribution network, this thesis researched two important ways to realize the self-healing function of the distribution grid from the strategic decision level: vulnerability assessment and network reconfiguration.Combining vulnerability with risk theory, this thesis introduces a method of vulnerability analysis based on risk assessment in distribution network. Considering some security indexes, risk indexes are established. It analyses vulnerability assessment of distribution network through fault probability and consequence. Based on the risk theory, this thesis defines four vulnerability indexes. Combine with these indexes the integrated system vulnerability (ISV) is estabilished. It synthetically assesses the security level of the grid.In this thesis, a new objective function is proposed:network reconfiguration for improving the ISV. After that, power distribution system is resolved into a series of loop, and a high efficiency GA algorithm is developed. In the proposed algorithm specific encoding method and gene operation strategies are employed and the infeasible produced during evolution are greatly reduced.