摘要
电磁安全距离的确定是当巡线直升机靠近导线时确保操作人员安全的有效保证。为此,通过有限元软件的数值仿真,首先对输电线路模型进行简化并应用镜像法对简化模型的有效性进行验证。模拟直升机悬浮于500kV超高压输电线路附近时,对直升机处于输电线路不同位置及不同距离时机身附近电场的畸变情况进行计算。结果表明:无直升机时,输电线路周围空间电场强度与其到最近的导线的距离近似呈反比例关系;有直升机时,直升机上最大电场强度与直升机到最近导线的距离近似呈反比例关系,场强最大值点主要出现在机翼上,大小约为没有直升机时的6～10倍;当直升机在地线附近时,由于地线屏蔽作用使得直升机上电场强度较小,该电场不影响直升机日常巡线。通过直升机上最大场强与直升机到导线距离的关系,确定在不同电场强度限值下直升机巡线的安全距离,当限值为500kV/m时,安全距离约为2.2m。
The determination of electromagnetic safety distance in helicopter power line patrol is the assurance for operators.Thus,the field distribution was calculated using a finite element software.In the beginning of the calculation,the transmission line model was simplified and verified by the image method.Then the field distortion near the helicopter was acquired at different positions and different distances when the helicopter was floating near the 500 kV transmission lines.The calculation result shows that,when no helicopter exists,the electric field strength around a transmission line is inversely proportional to the distance from the lines;when a helicopter exists,its maximum electric field strength is inversely proportional to its distance from the transmission.The maximum strength on the helicopter normally appears at the helicopter wing and is 6-10 times that without helicopter.Moreover,if the helicopter is near the earth wire,because of the shielding effect of grounding line,the helicopter＇s field strength becomes lower so as not to affect the helicopter inspection.According to the relationship of the maximum strength and the distance from helicopter to lines,the safety distance at different electric field intensity limit-values could be determined,e.g.,it is about 2.2 m with a limit-value of 500 kV/m.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2013年第1期201-209,共9页
High Voltage Engineering
基金
国家重点基础研究发展计划(973计划)(2009CB724503)
华北电网公司科技项目(2010-143)~~
关键词
直升机巡线
500KV线路
超高压
空间电场强度
电场数值仿真
悬浮电势
helicopter line inspection
500 kV transmision lines
extra-high voltage
space electric field intensity
electric field numerical simulation
suspension potential
