摘要
为获得循环应力-温度协同作用下绝缘纸加速老化实验的等效性,该文首先基于绝缘纸的三变量模型,推导出绝缘纸的稳态应变。基于时间-温度-应力等效性原理,联合自由体积理论,得到了计及应力频率的修正时间-温度-应力等效性理论。其次,在实验室中开展130℃条件下、4种应力水平和3个应力频率的加速机-热老化实验,并获得了应力水平和频率对绝缘纸抗张强度损失率模型的影响规律。然后,定义了应力-时间平移因子,得到绝缘纸抗张强度损失率主曲线,进一步提出一种平移因子的建立方法。该文结论从理论和实验两方面验证了绝缘纸加速机-热老化实验的等效性,可为绝缘纸加速老化实验与寿命评估提供理论支撑。
In order to obtain the equivalence of accelerated aging test of insulating paper under the synergistic effect of cyclic stress and temperature,the steady-state strain of insulating paper was derived based on the three-variable model of insulating paper.At First,based on the time-temperature-stress equivalence principle,combined with free volume theory,a modified time-temperature-stress equivalence theory considering the stress frequency was obtained.Secondly,a series of accelerated mechanical-thermal aging experiments were carried out at 130℃with 4 different stress levels and three different stress frequencies,and the influence of stress level and frequency on the tensile strength loss rate model of insulating paper was obtained.Then,the stress-time shift factor was defined,and the master curve of tensile strength loss rate of insulating paper was obtained,and a novel method to establish the shift factor was proposed.The conclusion of this paper verifies the equivalence of accelerated aging test and thermal aging test of insulating paper from both theoretical and experimental aspects,which can provide theoretical support for accelerated aging test and life evaluation of insulating paper.
作者
李长云
董嘉桦
孙丰田
LI Changyun;DONG Jiahua;SUN Fengtian(College of Electrical Engineering and Automation,Shandong University of Science and Technology,Qingdao 266590,Shandong Province,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2021年第23期8213-8222,共10页
Proceedings of the CSEE
基金
山东省重点研发计划项目(2019GGX102049)。
