纳米改性聚丙烯复合绝缘材料性能研究Ⅰ——在交流电场下的击穿特性

Research on the Properties of Nano-Modified Polypropylene Composite Insulating MaterialsⅠ-Breakdown Characteristics Under AC Electric Field

聚丙烯作为一种复合绝缘材料目前已广泛应用于射频电容器及电力电缆等设备中。聚丙烯混合天然纳米黏土颗粒后可作为一种纳米复合绝缘材料应用于实际工程中。本文旨在通过实验及理论的研究获取该复合绝缘材料的电气性能,为其应用提供技术支持。首先搭建了一套用于测试材料电气击穿特性的综合实验平台,接着分别在2种不同的加压方式下测量得到了混合不同重量比例(0%、2%和6%)纳米黏土颗粒的聚丙烯绝缘薄膜的电流密度及击穿场强值。研究结果表明:1)混合纳米颗粒的聚丙烯其击穿场强要明显高于未经纳米黏土添加的试品;2)复合绝缘材料电流密度与电场强度之间呈现非线性的函数关系,并有饱和趋势。随着电场强度的增加,复合绝缘材料的相对介电常数也发生着变化。在本文的实验样品范围内,纳米黏土颗粒的添加比重为2%时对于材料电气性能的提升较为明显。本文的研究成果可为聚丙烯复合绝缘材料的应用提供参考。

Polypropylene has been used in radio-frequency capacitors and power cables as composite insulating material.While being mixed with natural clay nano-particles,it can be used as a nanocomposite insulating material in practical engineering.The objective of this study is to evaluate the electrical properties of polypropylene filled with natural clay as nano-material.A comprehensive test platform for testing electrical breakdown characteristics of material samples is setup.Polypropylene samples having 0%,2%and 6%of natural clay by weight are exposed to voltages at two different rates-of-rise while measuring the RMS current.Breakdown voltages of each samples are also determined at two different ramp-rates.The important findings of this study are:1)The breakdown strength of the natural nanoclay filled polypropylene is higher than the unfilled polypropylene and the optimum concentration of nanoclay appeared to be 2%by weight;2)Within the scope of the experimental samples in this article,the addition of nanoclay particles at 2%will significantly improve the electrical properties of the material.The results of this paper can provide reference for the application of polypropylene composite insulation materials.