摘要
本文在对一个电磁悬浮转子实行线性控制研究的基础上,采用了两种非线性补偿控制,位移补偿和速度补偿。数字仿真结果表明,非线性补偿控制可使电磁悬浮转子达到更好的动态控制效果。
A Rotor suspended in electromagnetic bearings and a controller with sensors and power amplifierscompose a nonlinear mechanical and eletronic system,because the electromagnetic force is a nonlinear func-tion of the rotor's deflection and the control current.Therefore a commonly used linear controller can onlyprovide the system with a stable operation within a narrow frequency range.So it is necessary to attemptsome more effective control strategy such as nonlinear Control to improve its dynamic properties includingthe dynamic instability.The model of nonlinear control should be built on the basis of nonlinear characteristics or dynamic be-haviors of the system to be controlled.In this paper two kinds of nonlinear control model have been devel-oped,one is the deflection compensation,and the other is the frequency compensation.The former is ob-tained according to the nonlinear characteristic of electromagnetic force which is used to compensate for thedeflection nonlinearity of the system;and the latter is obtained according to the frequency characteristic of the dynamic response and the excitation of the system,which is used to compensate for the frequency non-linearity of the system.Both methods make the controller gain change in a nonlinear way with the variationof the system parameters.As a result,both of the frequency response and the dynamic instability of thesystem have been improved to a certain degree.The adoption of the deflection compensation brings an offset effect of the shaft centre's loci,althoughit can make some contribution to the improvement of the system stability.The frequency compensation canobtain even a better improvement of the system stability without occurence of offset shaft centre's locl.Sothe frequency compensation control is more suitable to be recommended.
出处
《振动工程学报》
EI
CSCD
1993年第4期386-393,共8页
Journal of Vibration Engineering
基金
国家自然科学基金资助项目
关键词
电磁轴承
非线性控制
线性控制
悬浮转子
electromagnetic bearings,nonlinear control system,linear control,compensation
