水轮机定子铁芯冲片外移事故有限元分析  

Finite element analysis for outer-movement accidents of stator core laminated sheets of hydro-generator

作　　者：李蔚[1] 张浩权[2] 钱泱[3] 蒋志强[1] 盛德仁[1] 

机构地区：[1]浙江大学热工与动力系统研究所,浙江杭州310027 [2]浙江省电力公司,浙江杭州310012 [3]紧水滩水力发电厂,浙江丽水323000

出　　处：《浙江大学学报（工学版）》2010年第5期1032-1037,共6页Journal of Zhejiang University：Engineering Science

摘　　要：采用有限元分析法,建立完整的定子模型,并采用热-结构耦合边界条件,对定子的温度场和应力场进行详细计算.计算结果表明,当定子铁芯两端施加的预紧力减弱、消失或冷却通风条件降低时,上、下两端冲片鸽尾槽的应力明显增大,从255MPa增大到439MPa;另外冲片鸽尾槽处的无过渡圆角设计,直接导致此处应力集中出现碎裂,在电磁拉力作用下发生冲片外移事故.建议同类型机组在检修时,应特别关注冲片的压紧程度,运行时应保持通风系统的清洁.A complete model of the stator based on the actual structure was established by using the finite element method. The stator temperature field and the stress field were calculated under the thermal-structural coupled-field boundary conditions. The effects on the stress of dovetail grooves at the upper and lower ends were analyzed by changing the pretightening force at both ends of the stator and the internal cooling and ventilation conditions. The stress of dovetail grooves significantly increased from 255 MPa to 439 MPa,when the imposed preload of the stator weakened,disappeared,or when the cooling conditions became worse. The dovetail grooves were designed without obvious fillets,which directly leaded to the stress concentration and the outer-movement accidents of stator core laminated sheets. The compression degree of the sheets should be concerned and the ventilation system must remain clean during the inspection of the same type units.

关 键 词：水轮发电机 定子铁芯 有限元分析(FEA) 应力场 

分 类 号：TM312[电气工程—电机] O242.21[理学—计算数学]