参数不确定下的磁悬浮双转子系统的动态特性

Dynamic Characteristics of Magnetic Suspended Dual-Rotor System with Uncertain Parameters

目前,关于电磁轴承支承特性的研究大多是基于PID类传递函数明确的控制算法展开的,而非线性控制算法的模糊属性导致难以建立电磁轴承的支承刚度和阻尼模型,系统的支承特性存在不确定性,从而难以对此类磁悬浮系统的动力学特性展开研究。为此,针对支承特性不确定下的磁悬浮双转子系统,首先,运用有限元法建立了磁悬浮双转子系统的理论模型;其次,将电磁轴承支承特性中的不确定量转化为‘未知而有界’的区间;最后,基于Chebyshev正交多项式的区间分析方法对磁悬浮双转子系统的动态特性展开了研究。研究结果表明,低频峰值响应的不确定度与等效刚度和阻尼呈现幂函数变化关系。

At present,the research on electromagnetic bearing characteristics are mostly based on PID control algorithm of class transfer function is clear,and the nonlinear control algorithm of fuzzy attributes lead to difficult to electromagnetic bearing supporting stiffness and damping model is established,the system bearing characteristics of uncertainty,which is hard to start a research on dynamic properties of this kind of magnetic suspended system.For this reason,aiming at the magnetic suspended dual-rotor system(MSDS)with uncertain bearing characteristics,firstly,the theoretical model of the MSDS is established by using finite element method.Secondly,the uncertainty in the bearing characteristics of the electromagnetic bearing is transformed into an interval of′unknown and bounded′.Finally,based on Chebyshev orthogonal polynomial interval analysis method,the dynamic characteristics of MSDS are studied.The results show that the uncertainty of the low frequency peak response is related to the change of the power function with the equivalent stiffness and damping.