Research On Voltage Equalizing Characters Of Segmented Composite Insulators On 330kV AC Transmission Lines

Insulators are important components of high-voltage transmission lines.In the northwest power grid,330kV transmission lines are the main ones,and silicone rubber composite insulators are most widely used.However,the mechanical performance of the silicone rubber composite insulator is poor,and it is vulnerable to strong wind or bird pecking.Due to the high mechanical strength of epoxy resin,some scholars have proposed to replace the silicone rubber material with epoxy resin.so as to solves the problem of bird pecking damage and external damage of strong wind.However,due to technical limitations,it is unable to meet the length requirements of composite insulator,so it is necessary to adopt the segmented form to connect two short composite insulators together through hardware to meet the insulation requirements of a long string of composite insulator.In this paper,the electric field distribution of the new 330kV segmented composite insulator is calculated,the parameters of the grading ring are optimized and analyzed,and a reasonable grading ring configuration mode is proposed.Firstly,the basic principle of the finite element method and its application in the electrostatic field are introduced.The finite element software is used to model the new 330kV segmented composite insulator.The whole process of modeling and solving is given.The principles and precautions in the process of modeling and solving are described in detail.Then,the electric field distribution of 330kV segmented composite insulator is calculated,and the influence of tower,grading ring and conductor on the electric field distribution is analyzed,which provides a reliable basis for the simplification of the model in the subsequent calculation.At the same time,three parameters,namely ring diameter,pipe diameter and upper shoulder position,were optimized and analyzed by exhaustive method,and a set of configuration parameters of the equalizing ring was recommended.Finally,the concept of sub model is applied,which makes the calculation model greatly simplified and the calculation speed greatly improved.By comparing with the calculation results of the whole model,it is found that the error is less than 5%.In addition,a hybrid differential multi-objective optimization algorithm is introduced,which effectively combines the advantages of the differential evolution algorithm and simulated annealing algorithm.through the iterative optimization algorithm calculates a set of the optimal configuration parameters,comparing with exhaustion method to calculate the result,the voltage equalizer of 330kV line sectional composite insulator is designed.