机械应力对硅橡胶电树枝起始性能的影响  

Effects of Mechanical Stress on Electrical Tree Initiation in Silicone Rubber

作　　者：周远翔[1] 张云霄[1] 陈铮铮[2] 刘睿[3] 陈明[1] 张灵[1] Zhou Yuanxiang Zhang Yunxiao Chen Zhengzheng Liu Rui Chen Ming Zhang Ling(State Key Laboratory of Control and Simulation of Power System and Generation Equipments, Tsinghua University, Beijing 100084, China China Electric Power Research Institute, Wuhan 430074, China State Grid Hubei Electric Power Research Institute, Wuhan 430077, China)

机构地区：[1]清华大学电机系电力系统及发电设备控制和仿真国家重点实验室,北京100084 [2]中国电力科学研究院,武汉430074 [3]国网湖北省电力公司电力科学研究院,武汉430077

出　　处：《绝缘材料》2017年第2期53-57,63,共6页Insulating Materials

基　　金：国家重点基础研究发展计划(973计划)项目(2014CB239501);国家电网公司科技项目(<直流交联电缆热特性及性能评价技术的研究>)

摘　　要：选取电缆附件用硅橡胶材料为研究对象,研究了不同机械应力(0~0.5 MPa)下硅橡胶材料内部电树枝的起始特性。测量了硅橡胶材料的应力应变曲线,结合Mooney-Rivlin模型进行仿真计算。结果表明:随着外施压力的增加,电树枝的起树电压单调下降,出现单枝状电树枝的概率增加,密集形态电树枝(松枝状和丛状)的出现比例下降。当压强大于0.3 MPa时,丛状和松枝状电树枝消失。硅橡胶材料在承受外施压应力时,在内部的正交方向上将产生拉伸应力,解释了硅橡胶电树枝的起始特性。在电缆设计过程中,需要综合考虑机械应力对电树枝特性的影响,以保证电缆绝缘的有效运行。The initiation characteristics of silicone rubber for cable accessories was studied under different mechanical stress（0~0.5 MPa）, and their stress-strain curves were measured and simulated with Mooney-Rivlin model. The results show that with the increase of applied stress, the initiation voltage of electrical tree decreases monotonically, the probability of single-branch-like trees increases, while the probability of intensive trees（pine-like and bush-like trees） decreases. When the pressure is greater than0.3 MPa, the pine-like and bush-like trees disappear. The silicone rubber would generate tensile stress inside its orthogonal direction when bearing stress, which explains the tree initiation characteristics in silicone rubber. The effects of mechanical stress on the characteristics of electrical tree need to be considered in cable design process to ensure the effective operation of cable insulation.

关 键 词：电树枝 硅橡胶 机械应力 起树电压 应力应变 

分 类 号：TM215[一般工业技术—材料科学与工程] TM201.4[电气工程—电工理论与新技术]