输电线路复合绝缘子伞裙与护套粘接界面强度预测

Prediction of interface strength of composite insulator umbrella skirt and sheath bonding of transmission lines

研究基于输电线路复荷绝缘子伞裙与护套粘接界面强度预测方法,明确复合绝缘子使用状态,使输电线路更好地进行电力传输。以FXBW-110/120-22型复合绝缘子为例,通过单边核磁共振传感器发射的CPMG脉冲序列,测量复合绝缘子伞裙与护套粘接界面横向弛豫时间,并经CPMG回波衰减数据双指数函数拟合,得到复合绝缘子伞裙与护套粘接界面强度衰减曲线,从而完成对伞裙与护套粘接界面强度的预测。实验结果表明,该方法利用横向弛豫时间进行复合绝缘子伞裙与护套粘接界面强度预测的灵敏度更高;在低温、高温环境、紫外线照射强度以及灰尘与泥土附着物含量增加的情况下,会导致复合绝缘子复合绝缘子等效横向弛豫时间降低,使伞裙与护套粘接界面强度衰减曲线衰减程度加大,降低伞裙护套粘接界面强度。

Based on the method of predicting the interface strength of the composite insulator umbrella skirt and sheath bonding of the transmission line,the use state of the composite insulator is clarified,so that the transmission line can better carry out power transmission.Taking the FXBW-110/120-22 composite insulator as an example,the lateral relaxation time of the bonding interface between the umbrella skirt and the sheath of the composite insulator was measured using the CPMG pulse sequence emitted by a unilateral nuclear magnetic resonance sensor.The strength attenuation curve of the bonding interface between the umbrella skirt and the sheath of the composite insulator was obtained by fitting the CPMG echo attenuation data with a double exponential function,thus completing the prediction of the bonding interface strength between the umbrella skirt and the sheath.The experimental results showed that this method had higher sensitivity in predicting the bonding interface strength between composite insulator umbrella skirt and sheath using lateral relaxation time.Under the condition of low temperature and high temperature environment,increased UV radiation intensity and dust and soil adhesion contentthe equivalent lateral re‐laxation time of composite insulators will decrease,resulting in an increase in the attenuation degree of the strength attenuation curve of the umbrella skirt and sheath bonding interface,and a decrease in the strength of the umbrella skirt and sheath bonding interface.