Research On On-line Monitoring System Of Lightning Over-voltage In Distribution Network Based On Edge Calculation

As a bridge and link between power system and power customers,the safe and stable operation of distribution network directly affects the reliability of power system.Comprehensive statistical analysis of distribution network operation data shows that lightning stroke fault is an important factor affecting the safe and stable operation of distribution network.With the continuous progress of economy and society,the coverage and scale of distribution network are expanding day by day,and new energy and load are continuously connected.Traditional lightning protection means and operation management mode of distribution network can no longer meet the requirements of rapid development of power grid and power customers for power supply reliability.Therefore,in order to ensure the safe and stable operation of distribution network,ensure uninterrupted power supply,and strengthen the research of online monitoring system of Lightning Overvoltage in distribution network,has important theoretical significance and practical engineering value.Firstly,on the basis of discussing the mechanism of lightning generation,lightning parameters,lightning protection performance index and trip condition,lightning overvoltage type,and comparing the advantages and disadvantages of various lightning protection principles and lightning protection measures in detail,Hilbert-Huang transform and wavclet transform are analyzed in detail.Wavelet transform method can be used for multi-resolution analysis,but it is essentially a constant multi-resolution analysis method and has the problem of selecting the optimal wavelet basis for different kinds of overvoltage;HHT can analyze linear signals,non-linear and non-stationary models,so using HHT algorithm to identify lightning overvoltage type has advantages.Secondly,the current situation and existing problems of lightning protection of distribution network in Zaozhuang area are analyzed,and the lightning overvoltage of distribution network is deeply studied by simulation.The calculation methods of direct lightning overvoltage and induced lightning overvoltage under different conditions are discussed in detail:Based on the characteristics of Zaozhuang distribution network,the lightning current,J.Marti overhead line and column composite insulator flashover component models are selected to build the simulation model of lOkV distribution line,and the lightning overvoltage simulation under different conditions is carried out;Through the simulation analysis of short-circuit fault identification,lightning-free lightning strike,counter-attack fault,bypass fault,and induced lightning fault over-voltage simulation analysis,various over-voltage characteristics are obtained,which provides criteria for lightning over-voltage identification classification.Finally,the development idea of the system is described in detail,and the framework of on-line lightning overvoltage monitoring system based on edge calculation is constructed.Detailed analysis of the principle of each unit part of the system,the HHT-based data analysis module extracts an overvoltage feature quantity;The front-end user interface of the system is built based on HTML and Javascript.Realize on-line monitoring of edge equipment,Using MySQL data server to realize data statistical analysis and fault point judgment.The system can improve the lightning protection ability of distribution network lines,speed up the emergency treatment efficiency of lightning accidents,and provide strong support for improving the reliability of distribution network power supply.