湿度对HTV硅橡胶臭氧老化特性的影响

Influence of Humidity on Ozone Aging Performance of HTV Silicon Rubber

为了研究湿度对HTV硅橡胶复合绝缘子臭氧老化的影响,将HTV硅橡胶试样置入臭氧体积分数为300×10-6环境中进行不同时间的老化。对老化后的试样进行了扫描电镜(SEM)、憎水性和热刺激电流(TSC)测试。试验结果表明,随着相对湿度的增加,试样表面的孔洞和裂纹增加;试样的静态接触角呈现下降趋势,并且试样的憎水性恢复速度较慢;同时随着相对湿度的增加,试样中逐渐出现次能级陷阱,主能级陷阱逐渐加深,陷阱电荷量也是增大的。由此可见,大气的湿度在复合绝缘子表面电晕老化过程中的作用不容忽视。

To study the influence of relative humidity on ozone aging of HTV silicone rubber composite insulators, samples of silicone rubber were put into ozone box with density of 300 ppm for different aging time. Scanning electron microscopy （SEM）, hydrophobicity and thermally stimulated current （TSC） were used to analyze the samples after aging. The test results show that： the amount of microvoids and cracks on surface increases, the hydrophobie contact angle trends to decline, and the speed of hydrophobic recovery becomes slower with the increase of relative humidity, however, the secondary level traps gradually occur, the main level traps gradually deepen, and the amount of trapped charge increases too. It is indicated that the effect of air humidity on corona aging of composite insulators can not be ignored.