脉冲电压下聚酰亚胺空间电荷密度对电荷激发分子振动的影响  

Effect of space charge density in polyimide on charge-excited molecular vibration under pulsed voltage

作　　者：侯健健 陈晨 郭昊鑫 王婵娟 刘学民 何东欣 HOU Jianjian;CHEN Chen;GUO Haoxin;WANG Chanjuan;LIU Xuemin;HE Dongxin(State Grid Shandong Guangrao Power Supply Company,Dongying 257300,China;Shandong Provincial Key Laboratory of UHV Transmission Technology and Equipment,School of Electrical Engineering,Shandong University,Jinan 250061,China;State Grid Shandong Dongying Power Supply Company,Dongying 257000,China)

机构地区：[1]国网山东省电力公司广饶县供电公司,山东东营257300 [2]山东大学电气工程学院山东省特高压输变电技术与装备重点实验室,山东济南250061 [3]国网山东省电力公司东营供电公司,山东东营257000

出　　处：《绝缘材料》2023年第8期73-79,共7页Insulating Materials

基　　金：国网山东省电力公司科技项目(520616220002)。

摘　　要：脉冲电压下绝缘更易发生早期失效,严重威胁电力电子器件及装备运行的稳定性。为探究脉冲电压下绝缘失效的微观机理,本文探究了聚酰亚胺中空间电荷密度对脉冲边沿时刻电荷激发分子振动的影响,并从频域的角度阐述了脉冲电压边沿时刻分子振动机理。结果表明:在直流电压的作用下聚酰亚胺试样内部积聚大量异极性空间电荷,导致分子振动波形极性发生反转;在脉冲电压上升沿频谱中,5×10^(6)~1×10^(7)Hz频段的电压分量对分子振动起主要作用。电荷激发分子振动会使得绝缘缺陷扩大,并最终导致绝缘失效。Insulating materials are more prone to early failure under pulsed voltage,which seriously threatens the stability of power electronic devices and equipment.In order to explore the microscopic mechanism of insulation failure under pulsed voltage,the effect of space charge density in polyimide on the charge-excited molecular vibration at the pulse edge was explored in this paper,and the molecular vibration mechanism at the pulse voltage edge was expounded from the perspective of frequency domain.The results show that there is a large amount of heteropolar space charges accumulated inside the polyimide sample under DC voltage,which leads to the reversal of polarity of the molecular vibration waveform.In the frequency spectrum of pulse voltage rising edge,the voltage component in the frequency band of 5×10^(6)-1×10^(7) Hz plays a major role in the molecular vibration.The charge-excited molecular vibration will expand the insulation defects and eventually lead to insulation failure.

关 键 词：脉冲电压 聚酰亚胺 空间电荷密度 电荷激发分子振动 

分 类 号：TM215[一般工业技术—材料科学与工程]