高压变频电机绕组端部防晕结构温升分布特性的研究

Study of Temperature Rise Distribution along Stress Grading System of HV Inverter-fed Motor

本文针对高压变频电机定子绕组端部防晕结构的高温升问题,建立了基于18kV变频电机绕组端部防晕结构的有限元电热耦合分析模型,仿真计算了多电平电压下防晕结构的电场与热场分布特性,研究了低阻防晕层电导率对热场分布的影响。仿真结果表明,多电平电压下槽口低阻防晕层会随着重复脉冲上升沿和下降沿而产生显著的电位提升和损耗增加,导致槽口低阻防晕层的温升高于高阻防晕层,而随着低阻防晕层电导率的增加,低阻防晕层的损耗和温升呈下降趋势。

In this paper,aiming at the problem of high temperature rise along the stress grading system of the high voltage(HV)inverter-fed motor stator end-winding,a finite element electro-thermal coupling analysis model based on the stress grading system at the endhang of an 18kV inverter-fed motor winding was established.The electric field and thermal field distribution characteristics of the stress grading system under multi-level voltage were simulated.The effect of the conductivity of the carbon armor coating on the thermal field distribution characteristics of the stress grading system was studied.The simulation results show that the carbon armor coating under multi-level voltage have a significant potential increase and loss increase with repeated pulse rising and falling edges,resulting in the higher temperature rise of the carbon armor coating than that of the stress grading coating.And as the conductivity of the carbon armor coating increases,the loss and temperature rise of the carbon armor coating perform a downward trend.