硅橡胶绝缘介质中电树的特性研究  

Growth Characteristics of Electrical Tree in Silicone Rubber

作　　者：夏岩松 彭岱 陈国东 马宗乐 郝东升 杨继东 刘玉明 魏福军 

机构地区：[1]冀北电力检修分公司,北京102488 [2]冀北电力物资供应公司,北京102488 [3]大连供电局,大连116001

出　　处：《高压电器》2013年第8期107-111,共5页High Voltage Apparatus

摘　　要：电树枝的生长是聚乙烯(PE)和交联聚乙烯(XLPE)电力电缆绝缘电老化的主要原因。电缆附件中结构复杂、电场分布不均匀,其主绝缘材料———硅橡胶长期处于高场强下。因此,非常有必要研究硅橡胶绝缘介质中电树枝的生长特性及机理。笔者选取了电缆附件应力锥的硅橡胶材料作为试验样本,研究了其电老化现象。实验过程中采用了典型的针—板电极,通过施加直流和交流电压以及改变试验参数等方式促进电树枝的生长。实验中使用数字显微成像系统实时拍摄了电树枝的整个生长过程。结果表明:硅橡胶绝缘介质中由硅的化合物形成的电树枝通道是绝缘的,完全不同于PE和XLPE电力电缆中具有导电或者半导电性质的碳化通道;电树枝的生长速度和结构完全依赖于试验电压种类、交流电压幅值和电源频率,随着电压幅值以及电源频率的增加,生长速度明显增快。Electrical tree in PE or XLPE cable, one of the electrical degradation phenomena, is considered an important reason for aging of the cable insulation. The cable accessories made of silicone rubber suffer from high intensity of electric field, therefore, it is necessary to investigate the tree growing chracteristics and mechanism in silicone rubber. In this study, silicone rubber for the stress cone was tested to investigate its electrical aging process. By applying DC and a series of AC voltages to the needle-plate electrodes, the growth characteristics and structures of electrical tree in the rubber were observed by a digital camera. Partial discharge appeared with the growth of electrical tree. The investigation shows that： the tree channel composed of silicone compounds in the rubber is non-conductive, which is quite different from the conductive or semi-conductive carbonized channel in PE and XLPE cables; the electrical tree＇s growth rate and structure exhibit remarkable dependence upon the frequency, amplitude, and type of voltage applied, and the growth rate accelarates with increasing voltage frequency and amplitude.

关 键 词：电缆附件 硅橡胶 电老化 电树 硅化合物 

分 类 号：TM247[一般工业技术—材料科学与工程]