使用磁流变阻尼器的大型汽轮发电机定子端部绕组振动控制

摘要

为控制大型二极汽轮发电机定子端部绕组产生的强迫振动,提出了基于磁流变阻尼器端部绕组的减振方法.将端部绕组及支撑结构简化为等效均质连续的三维板壳组合模型,采用Sigmoid力学模型计算阻尼器的阻尼力,建立了加装磁流变阻尼器的端部绕组的振动控制方程,通过直接积分法计算了电磁力作用下某大型汽轮发电机定子端部绕组加装磁流变阻尼器前后的振动响应.计算结果表明,磁流变阻尼器使端部绕组中径向、轴向动应力幅值分别降低了17.3％、55.9％,采用磁流变阻尼器是控制发电机端部绕组振动的一种有效方法.%To control the forced vibration of the stator end winding of large generators, a vibration isolation strategy based on magneto rheological damper is proposed. The stator end winding is simplified as a 3-D continuous homogeneous model of plates and shells, and the damping force produced by magneto rheological dampers is calculated adopting Sigmoid model. The governing equations of the stator end winding with magneto rheological dampers are discretized by finite element method. Forced responses of a stator end winding with and without magneto rheological dampers caused by electromagnetic forces are evaluated by numerical integration. The results show that dampers enable to reduce peaks of radial and axial stresses by 17. 3% and 55. 9% respectively.