Effect of void position on partial discharge properties in different insulating materials
Effect of void position on partial discharge properties in different insulating materials
复制标题
不同绝缘材料空隙位置对局部放电性能的影响
DOI：
10.1109/mepcon.2017.8301278
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
O. Zidane
中科院分区：
文献类型：
--
作者：
El;M. Elrahman;O. Zidane
不同类型的介质材料是电力系统的重要组成部分。这些材料总是在高电应力下工作，这会导致它们长期劣化。因此，局部放电(PD)是评估高压绝缘系统的重要工具，它是高电应力的结果。本文通过模拟和实验研究了工频正弦交流电压作用下不同介质材料的空穴放电特性。测试对象由不同绝缘材料中不同尺寸和位置的圆柱形孔洞组成，如硅橡胶、乙丙橡胶和高密度聚乙烯。采用COMSOL多物理软件进行有限元分析，使用LDD-6型局部放电分析仪进行实验研究。本文研究了改变孔洞的位置和尺寸对局部放电性能的影响。众所周知，孔洞内部的电场强度与外部电场的大小按介电常数之比有关。因此，均匀电场中孔洞位置的变化不应对孔洞内部的电应力产生影响。然而，所得到的结果表明，不同的孔洞位置对Pd的性质有影响。这可能是因为当空洞接近高压电极时，空洞两端的电势差以及起始电压值增加，当空洞接近接地电极时，反之亦然。当空穴位置由接地电极改为高压电极时，局部放电值增大。在相同的空隙尺寸下，高介电常数绝缘材料的Pd值变化幅度大于低介电常数绝缘材料。在均匀电场的情况下，采用Rogowski分布的电极，实验结果与模拟结果吻合较好。然而，对于非均匀场的情况，仍有许多工作要做。
Dielectric materials in their different types are an essential part of a power system. These materials always work under high electric stress which leads to their deterioration at a long run. Therefore, partial discharge (PD), which is a consequent of high electric stress, is an important tool for evaluating the high voltage insulation systems. In this paper, the properties of void discharges within different dielectric materials under sinusoidal AC voltage at power frequency were investigated experimentally and through modelling. The test object consists of a cylindrical void with different dimensions and positions in different insulating materials like Silicone Rubber, Ethylene Propylene Diene Monomer Rubber, and High-Density Polyethylene. The finite element analysis by using COMSOL Multiphysics software was used for modelling while the experimental work was done by using PD analyzer LDD-6. This paper includes studying the effect of changing the void position and dimension on the partial discharge properties. It is well known that the electric field intensity inside any void is related to the outside electric field according to the ratio of the permittivities. Therefore, the changing of void position in the uniform field should have no effect of the electric stress inside the void. However, the obtained results showed that the PD properties affected by different void positions. This may be due to increase the potential difference across the void as well as the inception voltage value when the void approaches to high voltage electrode, and vice versa, when it approaches to ground electrode. So that the partial discharge values increase when changing the void position from ground electrode to high voltage electrode. The change of PD values in high relative permittivity insulating material is higher than low relative permittivity materials at the same void dimension. The obtained results from the experimental work and simulating agree well for the case of a uniform field by using the electrode having the Rogowski profile. However, still much work has to be done for the case of a non-uniform field.