低气压下染污覆冰表面和冰凌间隙的直流电弧特性

Characteristics of Surface DC Arc on Pre-polluted Ice and Icicle-icicle Air Gap DC Arc Under Low Air Pressure

低气压下染污覆冰表面沿面电弧和冰凌空气间隙电弧伏安特性是研究高海拔、污秽、覆冰综合环境中绝缘子放电机理和放电模型的基础,为此,利用三角平板玻璃先染污后覆冰和冰凌间隙模型在低温低气压实验室分别试验研究了低气压下覆冰沿面电弧和冰凌间隙电弧直流伏安特性。结果表明:染污覆冰表面沿面电弧和冰凌间隙电弧的伏安特性E-I关系呈负幂函数,相同条件下,正极性沿面电弧电压高于负极性,而空气间隙电弧伏安特性受极性影响很小;沿面电弧和空气间隙电弧直流伏安特性均随着气压降低而下降,且空气间隙电弧受气压影响较沿面电弧大。研究结果为建立低气压下染污覆冰绝缘子串直流放电模型提供了基础。

Characteristics of surface DC arc on pre-polluted ice and icicle-icicle air gap DC arc under low air pressure is fundamental to the study on the discharge mechanism and the model of insulators under the combined conditions of high altitude,pollution and icing.We analyzed E-I characteristics of surface DC arc on pre-polluted plane triangular ice sample and icicle-icicle air gap DC arc under low air pressure in the low-temperature and low-pressure climate chamber.The results show that,the E-I curves of surface DC arc and icicle-icicle air gap DC arc are respectively in a negative power function relationship;the voltage of positive surface arc is higher than that of the negative one under the same conditions,while the polar of voltage has little effects on the E-I characteristics of icicle-icicle air gap DC arc;the E-I characteristics of surface DC arc and icicle-icicle air gap DC arc decrease with the decreasing air pressure,and icicle-icicle air gap arc is more remarkably affected by the pressure,compared with surface arc.The results can lay the foundation for the establishment of the DC discharge model of polluted and iced insulator strings under low air pressure.