地闪回击电流近区跨步电压研究  

Investigations on the Step Voltage Nearby the area Stroked by Lightning Current

作　　者：任合明[1] 周璧华[1] 杨春山[1] 石立华[1] 高成[1] 

机构地区：[1]解放军理工大学工程兵工程学院,南京210007

出　　处：《高电压技术》2005年第3期4-6,共3页High Voltage Engineering

基　　金：国家自然科学基金重点资助项目(50237040)

摘　　要：讨论了计算跨步电压常用的静电场算法的局限性,提出了采用近似镜像法及“近似镜像法+表面阻抗法”计算地闪回击电流附近地面水平电场来求取跨步电压的时域算法。根据人工引雷实测电流计算了其近区跨步电压的波形,取得了与实测数据一致的结果。计算结果表明,跨步电压随径向距离的变化规律在很大程度上取决于大地电导率,计算跨步电压的静电场公式即便用于计算跨步电压峰值,在大地电导率较高时也会有较大的误差。This paper discusses the limitation of the electrostatic method that is often used for calculating step voltage in engineering and presents a method to obtain step voltage by calculating the horizontal electric field on the ground near the area stroked by lightning using quasi-images formula and quasi-images formula + surface impedance formula. The waveform of step voltage calculated from a triggered lightning current is obtained and it is identical to the measured result. Further analysis shows that variation of step voltage with radial distance from lightning strike spot greatly depends on the electrical conductivity of ground. The electrostatic formulation will introduce large errors even in calculating the peak value of step voltage when the electric conductivity of ground is high.

关 键 词：雷电 水平电场 跨步电压 混合法 

分 类 号：TM865[电气工程—高电压与绝缘技术]