• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>2016 IEEE International Conference on High Voltage Engineering and Application >Novel unilateral NMR method for assessing the aging status of silicone rubber insulator
【24h】

Novel unilateral NMR method for assessing the aging status of silicone rubber insulator

机译：评估硅橡胶绝缘子老化状态的新型单边NMR方法

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Silicone rubber insulators are widely used in the power grid. An accurate estimation of the insulator aging status is necessary for electric power safety. In this study, a novel unilateral nuclear magnetic resonance (NMR) method to quantify insulator aging status is proposed. Firstly, a unilateral NMR sensor was designed specifically for measuring the transverse relaxation time (T2) of insulators. The main magnetic field B0 generated by the sensor possesses a constant gradient of 4.6 T/m along the vertical direction. And the B0 strength variation is less than 338 ppm in a 10×10 mm2 lateral area 1.9mm above the sensor. Secondly, in order to understand better the aging rules of silicone rubber insulators with the depth under the insulator surface, a step motor system was employed to control the penetration depth of the measurement area precisely. The transverse relaxation decay curves were obtained with the sensor by using the Carr-Purcell-Meiboom-Gill sequence at each layer. Thirdly, a data-processing method based on FFT and band-pass filter was utilized. With this method, the transverse relaxation information of the layer with the desired thickness was extracted. Finally, one-dimensional T2 distributions of each layer were obtained by applying inverse Laplace transformation on the filtered transverse relaxation decay curves. The mean values of the long NMR transverse relaxation time component (T2long-mean) were calculated to characterize the aging status of silicone rubber insulators. The one-dimensional depth profiles taken from three kinds of 220 kV silicone rubber insulators with different service times were compared. The results demonstrate that the insulator with a longer service time is characterized by a shorter relaxation time. Moreover, an increase in the penetration depth into the insulators clearly results in an increase in T2long-mean. However, all insulators tend to have nearly the same T2long-mean values at 0.75mm penetration depth into the insulators. This method could be applied to on-site detection in power system to take nondestructive examination of the insulating material aging status.
机译：硅橡胶绝缘子广泛用于电网。为了电力安全，必须准确估算绝缘子的老化状态。在这项研究中，提出了一种新颖的单边核磁共振（NMR）方法来量化绝缘子的老化状态。首先，单侧NMR传感器专门设计用于测量绝缘子的横向弛豫时间（T2）。传感器产生的主磁场B0沿垂直方向具有4.6 T / m的恒定梯度。在传感器上方1.9mm的10×10 mm2的横向区域中，B0强度变化小于338 ppm。其次，为了更好地了解硅橡胶绝缘子在绝缘子表面以下深度的老化规律，采用了步进电机系统来精确控制测量区域的穿透深度。通过在每一层使用Carr-Purcell-Meiboom-Gill序列使用传感器获得横向弛豫衰减曲线。第三，利用基于FFT和带通滤波器的数据处理方法。用这种方法，提取具有所需厚度的层的横向松弛信息。最后，通过对滤波后的横向弛豫衰减曲线进行逆拉普拉斯变换，获得每一层的一维T2分布。计算长NMR横向弛豫时间分量的平均值（T2long-mean），以表征硅橡胶绝缘子的老化状态。比较了三种使用时间不同的220 kV硅橡胶绝缘子的一维深度分布。结果表明，具有较长使用寿命的绝缘子具有较短的弛豫时间。此外，增加进入绝缘子的渗透深度显然导致T2长均值的增加。但是，所有绝缘子在穿透0.75mm的深度时趋向于具有几乎相同的T2长均值。该方法可应用于电力系统的现场检测，对绝缘材料的老化状态进行无损检测。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号