Experiment of electrothermal stress for different types of end turn grading in the inverter-fed form-wound windings  

作　　者：Wenhuan Zhao Peng Wang Yingwei Zhu Yue Zhang Shuai Yang Yan Liu Yang Shi Chaofan Yu 

机构地区：[1]Electrical Engineering Department,Sichuan University,Chengdu,Sichuan,China [2]D&R,Dongfang Electric Machinery Co.,Ltd.,Deyang,Sichuan,China

出　　处：《High Voltage》2024年第4期853-861,共9页高电压（英文）

基　　金：Science and Technology Department of Sichuan Province,Grant/Award Number:2021YFG0351;National Natural Science Foundation of China,Grant/Award Number:51977134。

摘　　要：End turn grading with resistive–capacitive coupling experiences severe electrothermal stress when subjected to pulse width modulation(PWM)voltage.In this paper,several experiments and simulations were carried conducted for four types of end turn grading.First of all,the temperature rise in the end turn grading increased with a decrease in rise time.When the rise time was less than 500 ns,the temperature rise at the terminal was higher owing to the increased capacitive current coupled from the main wall insulation.Further,the current in the linear region exhibited minimal variation at different fundamental frequencies resulting in synchronized the temperature rise at the terminal and overlap.Furthermore,the jump voltage was the key factor influencing temperature rise in end turn grading,confirmed by comparing different voltage magnitudes.Finally,the transient behaviour of the maximum field in the stress grading material was determined at rise time.The experimental and simulation results indicate that balancing and interdependently addressing the electrical and thermal stress protection in end turn grading is crucial.The study aims to provide an experimental and theoretical foundation for an insulation system of inverter-fed rotating machinery operating under PWM voltage.

关 键 词：stress INVERTER INSULATION 

分 类 号：TM464[电气工程—电器]