Karami Hamidreza, Azadifar Mohammad, Mostajabi Amirhossein, Rubinstein Marcos, Karami Hossein, Gharehpetian Gevork B, Rachidi Farhad
Electromagnetic Compatibility Laboratory, Swiss Federal Institute of Technology (EPFL), 1015 Lausanne, Switzerland.
Department of Electrical Engineering, Bu-Ali Sina University, 65178 Hamedan, Iran.
Sensors (Basel). 2020 Mar 5;20(5):1419. doi: 10.3390/s20051419.
In this work, we present a novel technique to locate partial discharge (PD) sources based on the concept of time reversal. The localization of the PD sources is of interest for numerous applications, including the monitoring of power transformers, Gas Insulated Substations, electric motors, super capacitors, or any other device or system that can suffer from PDs. To the best of the authors' knowledge, this is the first time that the concept of time reversal is applied to localize PD sources. Partial discharges emit both electromagnetic and acoustic waves. The proposed method can be used to localize PD sources using either electromagnetic or acoustic waves. As a proof of concept, we present only the results for the electromagnetic case. The proposed method consists of three general steps: (1) recording of the waves from the PD source(s) via proper sensor(s), (2) the time-reversal and back-propagation of the recorded signal(s) into the medium using numerical simulations, and (3) the localization of focal spots. We demonstrate that, unlike the conventional techniques based on the time difference of arrival, the proposed time reversal method can accurately localize PD sources using only one sensor. As a result, the proposed method is much more cost effective compared to existing techniques. The performance of the proposed method is tested considering practical scenarios in which none of the former developed methods can provide reasonable results. Moreover, the proposed method has the unique advantage of being able to locate multiple simultaneous PD sources and doing so with a single sensor. The efficiency of the method against the variation in the polarization of the PDs, their length, and against environmental noise is also investigated. Finally, the validity of the proposed procedure is tested against experimental observations.
在这项工作中，我们提出了一种基于时间反转概念来定位局部放电（PD）源的新技术。PD源的定位在众多应用中都备受关注，包括电力变压器、气体绝缘变电站、电动机、超级电容器或任何其他可能遭受局部放电的设备或系统的监测。据作者所知，这是首次将时间反转概念应用于PD源的定位。局部放电会同时发射电磁波和声波。所提出的方法可用于利用电磁波或声波来定位PD源。作为概念验证，我们仅展示了电磁情况的结果。所提出的方法包括三个一般步骤：（1）通过适当的传感器记录来自PD源的波；（2）使用数值模拟将记录的信号进行时间反转并反向传播到介质中；（3）定位焦点。我们证明，与基于到达时间差的传统技术不同，所提出的时间反转方法仅使用一个传感器就能准确地定位PD源。因此，与现有技术相比，所提出的方法具有更高的成本效益。在所提出的方法的性能测试中，考虑了以前开发的方法均无法提供合理结果的实际场景。此外，所提出的方法具有能够定位多个同时发生的PD源且仅用一个传感器就能做到这一点的独特优势。还研究了该方法在PD极化变化、其长度以及环境噪声方面的效率。最后，根据实验观测对所提出程序的有效性进行了测试。
