聚集态和陷阱对交联聚乙烯真空沿面闪络特性的影响

研究了半结晶聚合物交联聚乙烯的聚集态和陷阱等对真空沿面闪络特性的影响.交联聚乙烯(XLPE)在135℃下恒温10min后,分别经过-56℃,-25℃淬火处理,自然降温,或1℃/min,0.5℃/min慢速降温等热处理过程,测量了热处理后试样的电气性能、显微结构、陷阱分布和真空中的沿面闪络特性.实验结果表明,与未热处理试样相比,热处理试样的直流闪络电压最高提高了76%,脉冲闪络电压最高提高了19%.认为热处理改变了XLPE试样的聚集态和陷阱,从而提高了XLPE试样的真空沿面闪络性能,提出了可以通过控制半结晶聚合物的聚集态和缺陷结构提高其真空沿面闪络性能.

Influence of aggregation structure and traps on surface flashover of XLPE in vacuum

In the paper, the influence of aggregation structure and traps on both DC and impulse flashover voltage of semi-crystalline cross-linked polyethylene (XLPE) in vacuum are investigated. After heat t at 135 ℃ for 10min, the XLPE samples were quenched to -56 ℃ or -25 ℃, cooled normally, cooled at a rate of 1 ℃/min or 0.5 ℃/min to room temperature, respectively. The electrical properties, microstrueture and trap distribution of heat-treated samples were studied. Compared with untreated samples, it is found that the dc and impulse flashover voltages of heat treated samples are raised by 76% and 19%, respectively. It is proposed that the aggregation structure and trap level is changed by heat treatment, leading to the improvement of surface flashover properties in vacuum. It is suggested that the vacuum flashover characteristics can be improved by controlling the aggregation structure and trap levels of seml-crystalline polymers.