棒－板长空气间隙在低气压下雷电冲击特性及电压校正

文中在人工气候室内对0.5～2.0m的棒-板空气间隙雷电冲击50%放电电压U50与气压P的关系进行了系统的试验研究,分析了P对雷电冲击U50的影响,得到了U50与间隙距离d之间的关系.研究结果表明0.5～2.0m棒-板空气间隙的U50与P之间满足幂函数关系,其幂指数即气压对U50影响的特征指数n与电压极性有关;当d＜1.0m时,n与d关系较密切,当d＞1.0m时,n与d关系不明显,且U50与d基本呈线性关系.提出了棒-板长空气间隙雷电冲击U50的海拔高度校正方法,并得到海拔每升高1km,正、负极性的U50分别下降8.7%和8.0%.

LIGHTNING IMPULSE DISCHARGE PERFORMANCE AND VOLTAGE CORRECTION OF LONG AIR GAPS AT LOWER ATMOSPHERIC PRESSURE

Laboratory investigations of the lightning impulse discharge performance were carried out in the multifunction climate chamber for 0.5~2.0 m long air gaps at lower atmosphere pressures. The relationship between the 50% lightning impulse discharge voltage U50 and air gap distance d was obtained. It is shown that the relationship between the U50 and d can be expressed as a power function. The power index n is polarity dependent. At d < 1.0m, n is influenced by d, and at d >1.0m, n is independent with d. U50 is proportional to the air gap distance d. An altitude correction method for U50 is proposed. With the increasing of the altitude, the positive and negative 50% discharge voltage will decrease 8.7% and 8.0% per kilometer respectively.