强风作用下复合空心绝缘子的电场计算

高压断路器进出线的复合空心绝缘子主体长约8～10 m,弹性模量远小于瓷绝缘子。复合空心绝缘子在强风下会产生风偏,风偏量受风速大小和工作自身弹性模量影响。大幅风偏是否会引起复合空心绝缘子内外电场强度的畸变,劣化内外绝缘鲜有研究。由于高压复合空心绝缘子成本高,投运时间短,退运下来的样品较少。文中采用有限元分析的方法模拟强风工况,进行电场计算。针对750 kV断路器复合空心绝缘子在强风下振动的1阶模态振型,计算绝缘关键区域的电场强度,阐明风偏对接地屏蔽电极附近的电场畸变的危害最大,并给出了风速阈值。文中指出应该监测强风地区的风速、玻璃钢管的工作温度以及复合空心绝缘子的风偏量。

Electric Field Calculation of Composite Hollow Insulator with Strong Wind Reflection

The composite hollow insulator has a length of about 8~10 m,and the elastic modulus is less than porcelain insulator.The strong wind deflects the composite hollow insulator,where the wind deflection is affected by the wind speed and the elastic modulus under the working situation.Whether the large wind deflection will cause the distortion of the electric field strength inside and outside the composite hollow insulator,is rarely studied.Due to the high cost and fewer returned samples,in this paper,finite element analysis method is used to simulate the electric field the strong wind conditions.According to the first order modal vibration mode of the composite hollow insulator of 750 kV,the electric field in the critical region of the insulation is calculated.It is clarified that the wind reflection can cause severe distortion of the electric field near the grounding shield electrode.This paper points out that in the strong wind area,the wind speed,the working temperature of the FRP pipe and the wind reflection of the composite hollow insulator should be monitored.