1000kV变电站检修人员电场防护方法

摘要

1 000 kV变电站电压等级高、带电设备多,带电作业电场环境比常规输电线路更复杂,研究带电作业电场分布十分必要.基于三维有限元法,对变电站检修人员沿不同路径进入等电位过程中的表面场强进行计算,分析检修人员人体表面场强的分布特性,以及人体对电场的畸变作用;最后,提出带电作业过程中电场防护的基本要求.研究结果表明:在检修人员接近导线的过程中,电场畸变系数不断增大,等电位时检修人员表面场强最大值超过2 800 kV/m;检修人员头部、手尖和脚尖等部位场强明显高于其胸腹部场强;穿戴屏蔽效率不低于60 dB的屏蔽服并佩带屏蔽效率为20 dB的金属面罩可使检修人员的电场值低于国标规定的限值.%The electric field environment of live working in 1 000 kV substation is more serious than that of transmission lines because of the high voltage and large number of equipments,thus it is very necessary to research the electric field protection for live working in 1 000 kV substation.To ensure the safety of live working,the surface field strength of maintenance personnel during the process of entering equipotential electric field was calculated with three-dimensional finite element method.Then,the field strength distribution characteristic of the body surface was analyzed,and electric field distortion caused by the maintainer entrance was studied.Finally,the primary safety protection criterion during live working was proposed.The analysis results show that the distortion coefficient is increased during the process of entering equipotential electric field and the highest field strength is above 2 800 kV/m.The electric fields on worker's head,fingertips and feet are much higher than that on chest.The electric fields of the maintainer will remain below the national limits by adopting conductive clothing with 60 dB shielding efficiency and a metallic mask with 20 dB shielding efficiency.