The Study Of 35kV Overhead Line Design And Application In Yuhang District Of Hangzhou

With the rapid development of the national economy and the unceasing enhancement of people's living standards,35 kV line as an important energy transmission network link,has a vital role.On the current status of distribution network of Hangzhou,the 35 kV line and the voltage level of more than 35 kV line are still in the majority with overhead lines.The fault to these types of lines will cause huge economic losses on social production and people's life.Qianshui 3534 line in Yuhang District which this thesis focus on were put into operation in 1981,presents more aging and unreasonable design problems after experiencing nearly 30 years of operation,needing urgent modified.This paper focuses on a series of problems in Qianshui 3534 line in Yuhang District.35 kV distribution line,refers to the numerous domestic and international research achievements in the field of overhead line transformation and puts forward the renovation and redesign scheme.Firstly,using ATP electromagnetic transient simulation software to analyze the influencing factors of the lightning withstand level of overhead lines,and from two angles which are lightning current and tower wave impedance,to establish the tower model and then the simulation experiment was carried out.The results of the study show that: the smaller angle of protection and ground obliquity,the lower grounding resistance can reduce the risk of lightning shield the line.On the tower type selection,Shang font tower has a good performance in the lightning protection.According to the results,putting forward other measures to improve the level of resistance to lightning at the same time.Then introducing the hydrology and geographical situation of Yuhang district which is of great impact on the redesign of Qianshui 3534 line.Investigating the power grid operation and the status quo of the electrical equipment in recent years of this district,and analyzing various aspects of the aging line overhead lines redesign.Mainly including the overhead line path selection,tower type selection,grounding wire selection,insulator hardware selection and some other related problems.Finally according to the actual geographical condition and overhead line design specification,determined related equipment models of the Qianshui 35 kV overhead line after redesign in Yuhang district,and displayed the results.