Abstract：In this paper, a non-destructive method based on isothermal relaxation current theory was used to determine the insulation condition of stator bar. The stator bar specimens scaled down from the actual size were manufactured. The isothermal relaxation current of the specimens at different aging conditions were measured after thermal aging and electrical aging. According to the current data, the trap distribution in insulation was obtained. In thermocycling aging experiment, the post cure phenomenon exited. So the trap density in insulation increased at first and then decreased. In electric aging experiment, the specimen aged in electric field and the number of shallow traps in the specimen increased. Depending on the contribution of polarization process to the isothermal relaxation current, third order exponential model was obtained. The results show that the performance of stator bar aging is the interface defects between epoxy resin and mica tape increasing. Meanwhile, the fitting result of third order exponential model is accuracy enough.
曹雨, 吴建东, 刘松, 王立军, 朱慧盈, 尹毅. 单因子老化中定子线棒等温松弛电流的研究[J]. 电工技术学报, 2015, 30(1): 242-248.
Cao Yu, Wu Jiandong, Liu Song, Wang Lijun, Zhu Huiying, Yin Yi. Isothermal Relaxation Current Research of Stator Bar Insulation in Single Factor Aging Experiments. Transactions of China Electrotechnical Society, 2015, 30(1): 242-248.
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2015, Vol. 30 
