Optical and electrical acquisition of discharge phenomena on air gaps

在类似ATP/EMTP的仿真软件中，只有不准确的模型来模拟由于雷击引起的电力系统中的非常快速的暂态。对雷击架空线路绝缘子闪络过程的物理过程缺乏了解是该软件的主要缺陷。因此，绝缘配合计算需要考虑一些标准参数，如安全系数。因此，本研究项目的主要目标是克服这个问题，通过测量现有的过程中的情况下，绝缘子上的雷击，因为在电力系统中的雷击闪络。此外，测量结果应进行物理解释。为了提供对雷击闪络的物理理解，将使用一种开发的具有杆-杆电极的测量系统。绝缘子上最频繁的闪络可以通过棒-棒电极布置再现，然后可以同步测量脉冲发生器上的电压和两个电极上的电流。这里的主要挑战不仅是闪络电流测量，还包括预放电电流测量。在进行各种测量之后，将计算闪络的参数，例如电荷量、电荷载流子在气隙中的传播以及所施加电压的极性。此外，它将与杆-平面电极布置进行比较，这是已经研究过的。借助于经验和统计调查，杆-杆电极布置在标准雷电冲击电压下的闪络的各个阶段应该被识别和描述。这些结果是一个详细的物理过程建模的基础，在一个雷电闪络。本研究的进一步目标是提供一个基本的知识，在非标准的，振荡的雷电冲击电压下的过程，以调查在现实中发生在绝缘上的雷电闪络。针对这一建议，需要建立进一步的测量体系，并在本研究计划的基金支持下进行。因此，测量应进行的开发系统，以确定标准和非标准下的放电过程的差异，振荡雷电冲击电压。

In simulation software like ATP/EMTP, there are only inaccurate models to simulate very fast transients in power system due to lightning strikes. The lack of knowledge about physical processes in case of flashover on insulator caused by lightning strike on overhead lines is the main imperfection of such software. Therefore, some standard parameters like a safety factor are considered for insulation coordination calculations. Hence, the main goal of this research project is to overcome the issue by measuring the existing processes in case of lightning flashover on insulator because of a lightning strike in power systems. Moreover, the measurement results should be physically interpreted. To provide a physical comprehension about lightning flashover, a developed measurement system with a rod-rod electrode will be used. The most frequent flashover on insulators can be reproduced by a rod-rod electrode arrangement and thereafter, voltage at the impulse generator and the current at both electrodes can be synchronously measured.The main challenge here is not only the flashover current measurement but also the pre-discharge current measurement. After performing a variety of measurements, the parameters of flashover such as charge quantity, propagation of charge carriers in air gap and the polarity of the applied voltage will be calculated. Furthermore, it will be compared to/with the rod-plan electrode arrangement, which has been already investigated.With the aid of empirical and statistical investigation, the individual phases of flashover for rod-rod electrode arrangement under standard lightning impulse voltage should be identified and described. These results are the base for a detailed modelling of the physical processes during a lightning flashover.Further goal of this research is to provide a basic knowledge about processes under non-standard, oscillatory lightning impulse voltage in order to investigate the lightning flashover that occurs on insulation in reality. To this propose, a further measurement setup should be constructed, which should be supported by the fund of this research proposal. Consequently, measurements should be carried out by the developed system in order to identify the differences of discharge processes under standard and non-standard, oscillating lightning impulse voltage.