Research On Reliability Of Power Distribution Network With Distributed Generation

With the widespread application of distributed power sources in distribution networks,the topology of distribution networks has been transformed from a single-supply radial network into a complex network with multiple power supply bidirectional currents.Changes in the topology and operation mode of the distribution network with distributed power supply make the reliability assessment analysis and calculation methods of traditional distribution networks no longer fully applicable.Therefore,it is necessary to study the reliability assessment index system and reliability assessment analysis method of distribution network with distributed power supply.Based on the analysis of the reliability evaluation method of active distribution network and traditional distribution network,the reliability model of components and systems is established for the distribution network with distributed power supply,and some new reliability evaluation indicators are proposed.The reliability evaluation index system of distribution network has been improved.For the analysis of the distributed power characteristics of transient faults,a reliability model of the distribution network with distributed power is considered.Considering the impact of island operation on distribution network reliability,the dynamic island formation mechanism and partitioning algorithm are studied,and the improved breadth-first search algorithm is used for islanding.Aiming at the problem that the interval algorithm will produce overestimation,the affine algorithm and the interval minimum path algorithm are combined to propose an improved affine minimum path algorithm.The noise element is used to represent the correlation between variables,and the reliability evaluation of the whole system is improved..In the simulation study of the example,the modified IEEE RBTS BUS6 test system is used to analyze and study the reliability evaluation indicators and analysis algorithms.The simulation results of improved affine minimum path method and interval minimum path method show that the improved affine minimum path method improves the accuracy of reliability evaluation.At the same time,it is also found that the reliability calculation result is related to the error of the original parameters of the system,that is,the accuracy of the reliability calculation result of the distribution network increases with the increase of the original parameter error of the system.In addition,the influence effect of the reliability factors of distribution network with distributed power supply is simulated.