用折线法确定避雷针保护范围的防雷漏洞与改进  

Lightning Protection Loopholes and Improvement of Determining the Protection Range of Lightning Rod by Broken Line Method

作　　者：郑江[1] 林苗[1] ZHENG Jiang;LIN Miao(School of Electrical Engineering,Guangxi University,Nanning 530004,China)

机构地区：[1]广西大学电气工程学院,广西南宁530004

出　　处：《现代建筑电气》2024年第5期1-6,52,共7页Modern Architecture Electric

摘　　要：用现行折线法确定避雷针高度为h的保护范围,由于没有考虑h的有效保护范围的影响,单支h及两支等高h之间的保护范围均存在防雷漏洞。分析了这些防雷漏洞,并对折线法进行了改进:设h=30 m时h在0.5h高度处的有效保护半径为r_(h/2)=15 m,h的圆锥体及圆台体保护范围的地面有效保护半径分别为r_(01)=30 m,r_(02)=45 m,推导出当h>30 m时,h对圆锥体的保护角α′及h在任意高度处的保护半径r_(x)的计算公式;取D<2r_(01)或D<2r_(02)限制两支等高h的针间距离,按h_(0)=r_(01)或h_(0)=r_(02)为半径的圆弧确定两支等高h的针间保护范围。改进后随着h的增高,α′减小,r_(h/2)、r_(01)、r_(02)保持不变,单支h的保护范围被拉高变窄,单支h及两支等高h之间的保护范围均在h的有效保护范围之内,有效堵住了折线法的防雷漏洞。The current broken line method is used to determine the protection range of lightning rod with a height of h,because the effective protection range of h is not considered,there are lightning protection loopholes protection range of between single h and two equal height h.This paper analyzes these lightning protection loopholes,and improves the broken line method:When h=30 m,the effective protection radius of h at a height of 0.5 h is r_(h/2)=15 m,and the effective protection radius of the ground of the protection range of cone body and roundtable body of h are respectively r_(01)=30 m and r_(02)=45 m.The formula for calculating the protection angleα′of h to the cone body when h>30 m and the protection radius r_(x)of h at any height are derived.Take D<2 r_(01)or D<2 r_(02)to limit the distance between the two equal height h,and determine the protection range between the two equal height h according to the arc of h_(0)=r_(01)or h_(0)=r_(02)as the radius.After the improvement,with the increase of h,α′decreases,r_(h/2),r_(01)and r_(02)remain unchanged,and the protection range of single h is increased and narrowed,and the protection range between single h and two equal-height h is within the effective protection range of h,effectively blocking the lightning protection loophole of the broken line method.

关 键 词：避雷针 保护角 高度影响系数 折线法 保护范围 雷闪距离 

分 类 号：TU895[建筑科学]