等离子体改性纳米粒子对聚酰亚胺复合薄膜陷阱特性影响  

Influence of Nanoparticle Plasma Modification on Trap Properties of Polyimide Composite Films

作　　者：吴旭辉[1] 吴广宁[1] 杨雁[1] 张兴涛[1] 雷毅鑫 钟鑫[1] 朱健[1] WU Xuhui;WU Guangning;YANG Yan;ZHANG Xingtao;LEI Yixin;ZHONG Xin;ZHU Jian(College of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan Province, China)

机构地区：[1]西南交通大学电气工程学院

出　　处：《中国电机工程学报》2018年第11期3410-3418,共9页Proceedings of the CSEE

基　　金：国家杰出青年基金(51325704);工程电介质及其应用教育部重点实验室(KF20151109)~~

摘　　要：聚酰亚胺（Polyimide,PI）纳米复合薄膜以其优越的绝缘性能广泛应用于变频牵引电机匝间绝缘。为研究纳米粒子表面改性对复合薄膜陷阱特性以及绝缘特性的影响,利用大气压空气等离子体对纳米粒子表面进行改性,采用原位聚合法制备聚酰亚胺纳米复合薄膜,通过去极化热刺激电流（thermally stimulated depolarization current,TSDC）分析薄膜内陷阱能级密度分布,利用电声脉冲法（pulsed electro acoustic method,PEA）得到了薄膜的空间电荷分布情况,并测试得到方波脉冲下复合薄膜的绝缘寿命。研究结果表明,纳米粒子经过等离子体改性后,聚酰亚胺纳米复合薄膜陷阱能级峰位移向低能级,浅陷阱密度由7.15×1019（1/m3）增至9.99×1019（1/m3）,而深陷阱密度由7.63×1019（1/m3）降至5.33×1019（1/m3）,浅陷阱密度的增加有效抑制了薄膜内空间电荷的积累,空间电荷密度最大值由6.93C/m3降至3.59C/m3,同时聚酰亚胺复合薄膜的绝缘寿命提高了28.06%;讨论分析了纳米粒子表面改性对聚酰亚胺复合薄膜内陷阱分布影响,并揭示了陷阱特性对薄膜空间电荷分布以及绝缘寿命的影响机理。Polyimide（PI） nanocomposite film is widely used in frequency conversion traction motor inter turn insulation because of its excellent insulation performance. In order to study the influence of surface modification of nanoparticles on the trapping characteristics and insulation characteristics of composite films, the surface of nanoparticles was modified by atmospheric pressure air plasma and polyimide nanocomposite films were prepared by in situ polymerization, the trap level distribution was obtained by thermally stimulated depolarization current （TSDC）, and the space charge distribution was obtained by pulsed electro acoustic method （PEA）, besides, the insulation life of composite films under square wave pulse was tested. The results showed that after the treatment of nanoparticles with plasma, the peak position of trap level of polyimide nanocomposite film was move to lower level, the shallow trap density was increased from 7.15× 1019（1/m3） to 9.99×1019（1/m3）, and the deep trap density was decreased from 7.63×1019 （1/m3） to 5.33 × 1019 （1/m3）, and the accumulation of space charge was effectively suppressed because of the increase of the shallow trap density, so that the maximum value of space charge density was decreased from 6.93 C/m3 to 3.59 C/m3, and as a result, the insulation life of the film was increased by 28.06%. Finally, the influence of surface modification of nanoparticles on the trap distribution in polyimide composite film was discussed and the mechanism of the influence of trap characteristics on the space charge distribution and the insulation life of the film was revealed.

关 键 词：纳米粒子表面改性 聚酰亚胺 空间电荷 去极化热刺激电流 陷阱特性 绝缘寿命 

分 类 号：TM215[一般工业技术—材料科学与工程]