【摘要】 为模拟220 kV下运行的整体预制式电缆接头的硅橡胶绝缘层热老化情况,在200℃下对电缆接头进行加速热老化试验,并对不同老化时间的试样进行电气试验。搭建了电缆接头热老化试样的超声检测平台,测试了不同热老化试样的超声声速特性。结果表明:随着老化时间的增加,硅橡胶电缆接头绝缘层的电气性能逐渐降低,超声声速也逐渐降低。将超声声速与电气性能通过函数拟合,发现超声声速特性与相对介电常数有良好的对应性,而与电气强度没有明显的对应关系。因此,超声声速可以作为评估电缆接头硅橡胶绝缘层热老化状态的重要参数。更多还原

【Abstract】 In order to simulate the thermal ageing state of silicone rubber insulation layer in integral prefabricated cable joint operating at 220 kV, we conducted accelerated thermal ageing tests on cable joint at 200℃, and the electrical properties of the aged samples with different ageing time were tested.An ultrasonic testing platform for the thermal aged cable joint was built, and the ultrasonic sound velocity characteristics of the different thermal aged samples were tested. The results show that with the increase of ageing time, the electrical properties of silicone rubber cable joint insulation layer decreases gradually, and the ultrasonic velocity also decreases gradually. By fitting the ultrasonic velocity with electrical properties through function, it is found that the ultrasonic velocity characteristics has good corresponding relation with relative dielectric constant, but have no obvious corresponding relation with electric strength. Therefore, the ultrasonic velocity can be used as an important parameter to evaluate the thermal ageing state of silicone rubber insulation layer for cable joints.更多还原