Abstract：Partial discharge(PD) under a sequence of high-frequency pulse is one of the key factors which lead to premature failure of turn insulation of inverter-fed motors. Aging experiments for turn insulation samples under bipolar continuous square impulse voltage were done. The number and mean quantity of PDs under impulse voltage were studied. By means of scanning electron microscope (SEM), the microcosmic morphologies of surface of turn insulation were analyzed. The results reveal that the relationship of PD parameters(PD number and mean PD amplitude value) between aging time is complicated. The damage of polyimide nano-composite film is concentrated on the degradation of polymer matrix in the presence of PDs. The residual nano-fillers remain on the surface and form an inorganic insulation layer to resist the further damage of PDs. It is the symbol of faults expanding rapidly when the floccules and voids form on the surface, which leads insulation failure.
罗, 杨, 吴广宁, 刘继午, 朱光亚, 彭, 佳, 曹开江, 张依强. 局部放电作用对变频电机匝间纳米复合绝缘的损伤机理研究[J]. 电工技术学报, 2014, 29(6): 303-310.
Luo Yang, Wu Guangning, Liu Jiwu, Zhu Guangya, Peng Jia, Cao Kaijiang, Zhang Yiqiang. Study on PD Damage Mechanism of Nano-composite Used as Turn Insulation in Inverter-Fed Traction Motors. Transactions of China Electrotechnical Society, 2014, 29(6): 303-310.
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2014, Vol. 29 
