Study On Distribution Network Topology Identification Based On Synchronous Phasor Measurement

As the last link of power system,distribution network affects the security,reliability and economy of power supply.Network topology parameters is the basement of many advanced applications in distribution network management system,so the correctness and real-time of distribution network topology identification is of great significance.With the wide application of distributed generation,distribution network topology changes more frequently,which presents a higher challenge to topology identification.The topology of distribution network is complex and the power flow is much smaller than that of transmission network.The traditional phasor measurement unit has limitations in the monitoring of distribution network.According to the characteristics of distribution network and the demand for synchronous phasor measurement unit,a miniaturization and low cost synchronous phasor measurement unit of distribution network is introduced firstly.The device can complete the acquisition of current and voltage with high accuracy and sampling rate.It has self-powered technology form the power line and can provide required data for topology identification and other applications.Secondly,using the phase angle information measured by the measurement unit as the main parameters for distribution topology identification.In order to be closely related to the actual operation,the topology identification is divided into two scenarios to meet the requirements of reliability and the real-time requirement.The simulation result proves that the proposed method is simple and feasible.The islanding detection is included in the scope of distribution network topology identification.The traditional characteristic quantity and the characteristic quantity extracted by the signal processting technology are combined into vector and identified by the BP neural network to detect the islanding effect and other interference phenomenon.Finally,the optimal PMU placement method is analysed.This paper proposed an improved BPSO algorithm for PMU optimization allocation,aiming at the whole network node observable.The vulnerability of buses is analysed,and an optimal configuration scheme of PMU considering both reliability and economy is given.A simulation case is given to verify the method.The results shou that the method can satisfy the network observability,maximize the reliabiligy and economy,and ensure the correct rate of topology identification.