The Risk Assessment Of Urban Distribution Network Based With Loop Closing Operation

Urban Mid-Voltage Distribution Network is an important link in connection withthe power points and users, and it acts in the role that transmits and distributes electricpower to the users. And gridstructure of the urban medium-voltage distributionnetwork is weak, they will lose a lot of money when power failure occurs. Socarrying out risk assessment of urban medium-voltage distribution and find theweaknesses to avoid occurring the power failure accident are important.The ideal risk assessment model must consider the gridstructure. The thesis isbased on security and reliability. At first risk identification to the urbanmedium-voltage distribution network, and then find the most important risk sources,analyses the faults and severity of the most important risk sources. At last buliding therisk assessment models, establish risk assessment model indicators.In addition, with the higher requirement of uses for the quality of electricityincreasing, the loop closing operation has become a common means of improvingreliability. The thesis analysis the loop closing operation deeply, put forward decisionscheme to judge. The analysis of examples show that the decision scheme is correct,elucidates reasons can not execute loop closing operation.Finally, the risk of actual urban distribution network is evaluated by theestablished risk assessment models and the risk method.