特高压线路瓷绝缘子污秽分布特性研究

Ｒesearch on Pollution Distribution Characteristics of Ceramic Insulators in UHV Transmission Lines

摘要:

绝缘问题是特高压输电建设中需要解决的首要问题，研究不同气候不同电压类型条件下输电线路绝缘子积 污分布对指导输电线路外绝缘设计具有重要意义。以特高压输电线路广泛使用的陶瓷绝缘子为研究对象，建立电场 等效模型，通过调整 3 片绝缘子伞裙两端电压模拟实际特高压输电线路绝缘子串周围电场情况，并基于实验室搭建的 人工雾室模拟南北方典型气候，在不同电压类型下开展了陶瓷绝缘子积污试验。研究结果表明: 在南方沿海气候下， 由于空气湿度较大，两种电压类型下的陶瓷绝缘子表面积污量均高于北方地区; 绝缘子串的积污量随电压等级的升 高而增大; 在两种气候下，陶瓷绝缘子串在直流电压作用下积污量呈现两端高、中间低的现象，而交流电压下积污量 变化不大，且直流电压较同等级交流电压作用下绝缘子片上下伞面的积污量更大; 南方和北方气候下陶瓷绝缘子直 流和交流电压下积污比分别约为 1． 37 和 1． 51。

Abstract:

Insulation is the most important problem to be solved in the construction of UHV transmission lines． It is of great significance to study the pollution distribution of transmission line insulators under different climates and voltage types． Taking ceramic insulator which is widely used in UHV transmission lines as the research object，the electric field equivalent model is established，and the electric field around the actual insulator string of UHV transmission lines is simulated by adjusting the voltage at the ends of 3 insulator sheds． Typical climates in the north and south are simulated，and pollution accumulation tests of the ceramic insulator are carried out under different voltage types based on the artificial fog chamber built in the laboratory， and the effectiveness of the model is verified． The research results show that in the southern coastal climate，the pollution accumulation on ceramic insulator surfaces are higher than that in the northern climate under two voltage types because of the high humidity of the air． Under DC and AC voltage，the pollution accumulation quality of insulator string increases with the increase of the voltage level． In both climates，the pollution accumulation quality on insulator string under the action of DC voltage on two ends sheds is higher than the middle shed，while the pollution accumulation quality on the upper surfaces of 3 sheds is about the same under AC voltage． And the pollution accumulation quality on the upper and the lower surfaces of 3 insulator sheds under DC voltage is higher than that under the same AC voltage level． The contamination ratio of the ceramic insulator string under DC and AC voltages in southern climate is about 1． 37，while that of northern climate is about 1． 51．