高海拔沙尘环境对典型长间隙操作冲击放电特性的影响

沙尘条件下输电线路容易发生闪络和跳闸事故.为了研究不同沙尘环境参数对输电线路外绝缘性能的影响,设计了能够调节沙尘天气强度、风沙流风速、沙尘含盐比、粒径和沙尘荷电量的沙尘环境模拟系统,利用额定电压为2400 kV的冲击电压发生器产生标准正极性操作冲击电压波,在青海塔拉地区(海拔3000 m)对1、2、3 m间隙距离的棒-棒、棒-板长空气间隙进行正极性放电特性研究.试验结果表明:风和沙尘混合作用下,间隙的50％操作冲击放电电压随着风速的增大而降低,且下降幅度随着间隙距离的增大而增大;沙尘环境对间隙的操作冲击放电特性既有促进作用也有抑制作用.

Influence of sand and dust environment in high altitude area on impulse discharge characteristics of typical long gap operation

Transmission lines are prone to flashover and tripping accidents under sand and dust conditions. In order to study the influence of different sand and dust environmental parameters on the external insulation performance of transmission lines, a sand-dust environment simulation system that can adjust the intensity of sand-dust weather, wind speed, sand-dust salt ratio, particle size, and sand-dust charge was used to create a dusty environment. An impulse voltage generator with a rated voltage of 2400kV was used to generate a standard positive polarity operating impulse voltage wave, the positive polarity discharge characteristics of the rod-rod and rod-plate long air gaps of 1m, 2m and 3m was studied in the Qinghai Tala area (3000 meters above sea level). The results show that under the mixed action of wind and dust, the 50% operating impulse discharge voltage of the gap decreases with the increase of wind speed, and the decreasing amplitude increases with the increase of the gap distance. It is concluded that sand and dust environment can promote and inhibit the operating impact discharge characteristics of the gap.