机电复合作用下发电电动机磁极连接线建模及应力分析

Modeling and Stress Analysis of Magnetic Pole Connection Line of Generator-Motor under Combined Action of Electromechanical Factors

针对抽水蓄能机组发电电动机转子磁极连接线现有设计校核往往仅考虑单一机械应力作用,提出计及机端短路故障的机电复合作用下发电电动机磁极连接线建模及应力分析方法。首先,基于有限元方法建立某抽水蓄能机组发电电动机转子结构有限元模型,得到磁极连接线不同工况下单一机械应力结果,然后建立机端三相短路故障下发电电动机电磁场有限元模型,得到计及故障下电磁力作用的机电复合应力结果。结果表明,磁极连接线飞逸工况下承受机械应力约为额定工况时的2倍,电磁力对磁极连接线不同区域影响不均,受力方向和大小的变化规律与机械应力不同,机电复合作用下会造成磁极连接线局部应力激增。

Aiming at the fact that the current design and verification of the rotor magnetic pole connection line of the pumped storage motor usually only considers the single mechanical stress,the modeling and stress analysis method of the rotor magnetic pole connection line of the electric motor under the combined action of electromechanical factors including the terminal short circuit fault is proposed.First of all,the finite element method was used to establish rotor structure finite element model of a certain pumped storage units generator motor,and the magnetic pole connection line single mechanical stress results was obtained under different working conditions.Then electromagnetic field finite element model was established under the three-phase short-circuit at the side of the motor,and the results of electromechanical composite stress under the action of electromagnetic force are obtained.The results show that the mechanical stress of the magnetic pole connection line under the runway speed working condition is about twice as high as that under the rated working condition,the electromagnetic force has uneven impact on different areas of the magnetic pole connection line,and the law of force direction and size is different from the mechanical stress.Mechanical and electrical composite action will cause local stress surge of magnetic pole connection line.