聚合物绝缘研究中的微电流测量

为了从微观上解释绝缘聚合物的电老化与材料结构变化间的关系,国际上广泛开展了空间电荷理论及测量的研究。热刺激电流是材料极化后随温度升高释放的pA级电流,是一种研究聚合物绝缘材料在电气压力下内部微观结构变化的重要手段。本文设计了微电流测量电路,同时讨论了影响该电流测量的因素,包括抗干扰和数据采集、处理等技术。实测了纳米和非纳米材料的热刺激电流,分析了不同绝缘材料的热刺激电流特征和微观结构间联系。

The Measurement of Weak Current in Insulation Polymer

In order to explain the phenomenon of the polymer aged even breakdown under electric stress,the relationship between the space charge and the microstructure of polymer has being widely studied both in domestic and abroad laboratories.Thermally stimulated current(TSC) is weak current up to pA released by material when the material is heated after poling.It is an important method to study the space charge accumulation and the changes of microstructure in polymer.A new device is designed to measure the TSC of the polymer,and some influencing factor is also considered.Some effective methods(e.g.,anti-interference,data acquisition) are used in order to improve effect of measurement.The TSC curves of nanophase and normal polymer are also tested,and some useful conclusions can be concluded according to these results.