冰柱直流放电特性及路径

冰的电气特性影响输电线路覆冰绝缘子闪络电压。该文选择冰柱为试品，在人工气候室内研究了冰柱直流放电路径和表面闪络特性，从而探讨覆冰绝缘子闪络的一般规律。试验和分析结果表明：电极布置方式不同，沿冰柱放电的路径发生变化。覆冰水电导率和气压是影响冰柱和覆冰绝缘子闪络电压的2个重要参数，随着覆冰水电导率的增加或气压的降低，冰闪电压下降。根据试验结果，文中给出了冰柱闪络电压与覆冰水电导率和气压的关系。冰柱闪络电压的极性效应明显，正极性闪络电压低于负极性的。临界闪络电流随着气压的降低明显减小。

DC Discharge Performance and Path of Ice Column

The flashover voltage of iced insulators of transmission lines is affected by the electrical characteristic of ice. An ice column was selected as the sample to study the DC discharge path and flashover performance on ice surfaces in the artificial climate chamber and the generic rule of flashover of iced insulators was discussed. The experimental and analytical results show that the discharge path along the ice column will change with the different disposal of the electrodes. The freezing-water conductivity and the air pressure are the two important factors affecting the flashover voltages of the ice column or iced insulators, the ice flashover voltages will decrease with the increase of the freezing-water conductivity or the decrease of the air pressure. Based on the test results, the relation between the flashover voltage of the ice column and the freezing-water conductivity or the air pressure was presented. The polarity effect of flashover voltages of the ice column is obvious and the positive flashover voltages are lower than negative ones. The critical flashover current reduces with the decrease of air pressure.