为了研究高海拔地区空气间隙的操作冲击特性,在大型人工气候室内对0.25~2m的棒-板间隙的操作冲击50%放电电压与气压p、间隙距离d的关系进行了系统的实验研究。结果表明:操作冲击50%放电电压U50随着气压p的下降呈幂指数关系下降,间隙长度不同,气压影响指数n不同;通过分析得到了不同间隙长度下的U50气压校正公式;U50与不同间隙距离d之间的关系与电压极性有关:正极性时U50与间隙距离d的线性关系较好,负极性时有明显的饱和性,且U50的气压影响特征指数n与电压极性有关。试验结果显示操作冲击50%放电击穿时间与电压极性和间隙距离有关。
The systemic switching impulse discharge tests of rod-plane air gaps with 0.25-2 m length were carried out in the large multi-function artificial climate chamber. The results show that the relationship between 50% switching impulse breakdown voltage Us0 and the air pressure p is a power function, and the air pressure exponent n is influenced by the gaps length. The voltage correction formulas at low air pressure are gained by analyzing the experimental data. U50 is affected by voltage polarity, there is a nearly linear relation between the positive voltage and the gap length d while there is a nonlinear relation between the negative voltage and d. The exponent n is affected by voltage polarity also. The test results show that the voltage polarity and gap length have influences on the switching impulse breakdown time.