摘要
水轮发电机组转子相对偏心引起的不平衡磁拉力对转子振动有较大影响。从水轮发电机转子的气隙磁场能表达式出发,推导发电机转子的电磁刚度矩阵。利用拉格郎日方程,建立了刚性和短轴承弹性两种支承方式下考虑电磁刚度的转子振动模型。利用李雅普诺夫非线性振动稳定性理论,研究了电磁刚度和轴承弹性支承对转子的临界转速和偏心力作用下的横振幅值的影响,并分析了电磁、机械、轴承等参数对临界转速的影响程度。为进一步深入研究水轮发电机组轴系统在电磁,水力和机械结构参数共同作用下的动力特性打下基础。
The unbalance magnetic pull on the rotor of an eccentric water turbine generator set has important influence on its vibration.The magnetic stiffness matrix was introduced to express the energy of the magnetic field in air gap.Two vibration models were constructed,making use of lagrange equation.The difference between the two models lies in the boundary supporting conditions:one is rigidly supported and the other is with elastic bearing supports.The influences of magnetic stiffness and elastic supports on the critical speed of rotor were studied using Liapunov nonlinear vibration theory.The vibration amplitude of the rotor was calculated,taking the magnetic stiffness and eccentrical force into account.The sensitivities of the magnetic,mechanical and bearing parameters with respect to the critical speed were analyzed.Some conclusions may be benefit to the study of dynamic characters of the generator set shaft system which concludes all the magnetic,mechanical and hydraulic parameters.
出处
《振动与冲击》
EI
CSCD
北大核心
2010年第8期169-173,共5页
Journal of Vibration and Shock
基金
国家自然科学基金(50679009)
关键词
水轮发电机转子
非线性振动
电磁刚度
轴承
临界转速
rotor of water turbine generator set
nonlinear vibration
magnetic stiffness
bearing
critical speed
