聚合物绝缘材料载流子陷阱的表征方法及陷阱对绝缘击穿影响的研究进展

聚合物绝缘材料在电气设备中已得到广泛应用,其绝缘安全对电气设备的可靠服役具有显著影响。由于聚合物材料内部因生产工艺、运行老化等原因形成大量的载流子陷阱,为空间电荷的积聚提供了条件,从而使聚合物绝缘材料面临着击穿破坏的风险,严重威胁其运行安全。因此,对聚合物绝缘材料内部的载流子陷阱进行有效表征,探寻其与材料老化、击穿的相关性,对于保障绝缘材料安全具有重要意义。针对聚合物绝缘材料载流子陷阱表征方法的研究进展进行总结,分析并评述了各类材料陷阱表征方法的基本原理、应用及局限性。研究表明:等温表面电位衰减法、热刺激电流法、光刺激放电法和电声脉冲法均可有效进行载流子陷阱的表征,但需进一步建立精细化数学模型以适用于不同尺寸规格的样品,并探究多种表征方法的内在关联性,发展聚合物材料载流子陷阱的三维成像技术。通过各类物理、化学手段实施聚合物材料的陷阱调控或陷阱编缉,可为提高材料的绝缘性能提供了新的思路。

Characterization Method for Carrier Trap and the Effect on Insulation Breakdown Within Polymer Insulating Materials: A Review

Polymer insulating materials have been widely used in electrical equipment, and their insulation safety has a significant impact on the reliable service of electrical equipment. The formation of a large number of carrier traps in polymer materials due to the production process and the aging of the operation provides the conditions for the accumulation of space charge, so that it makes polymeric materials to face the risk of breakdown and seriously threatens its safe operation. Therefore, characterizing the carrier traps in the polymeric insulators and exploring the correlation with aging and breakdown of materials are important for their safety. So, we summarized the research progress of characterization methods for carrier trapping of polymer insulating materials, and analyzed and reviewed the basic principles, applications, and limitations of various materials trap characterization methods. It is suggested that isothermal surface potential decay, thermally stimulated current, photo stimulated discharge, and pulsed electroacoustic methods exhibit high effectiveness for carrier trap characterization. However, detailed mathematical models are still needed for samples with various sizes, the intrinsic relations among the measurements should be further investigated, and three-dimensional mapping technique for the trap should be developed. It is possible to employ physical or chemical methods to modulate or edit the trap, by which the insulation property of the material can be improved.