基于系统辨识的轴向磁悬浮轴承建模研究  

Research of modeling axial magnetic bearing based on system identification

作　　者：宋学涛 邓智泉[1] SONG Xuetao;DENG Zhiquan(College of Automation Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)

机构地区：[1]南京航空航天大学自动化学院,江苏南京211106

出　　处：《电机与控制学报》2024年第10期76-84,共9页Electric Machines and Control

摘　　要：磁悬浮轴承可有效地提升高速电机的临界转速,然而轴向磁悬浮轴承在转子高转速和材料实心的情况下涡流效应显著。针对该情况下实心轴向磁悬浮轴承的建模问题,使用等效磁路法建立轴向磁悬浮轴承模型时常会忽略涡流效应,导致理论模型与实际模型存在较大误差。为了得到更贴近实际的轴向磁悬浮轴承精确模型,针对一种混合型三自由度磁悬浮轴承的轴向部分采用系统辨识的方法进行了闭环辨识,研究了分数阶模型阶次的确定流程和误差准则,得到了轴向磁悬浮轴承的数学模型。结果表明,分数阶系统模型能够弥补整数阶模型在高频段上的相位特性误差,在整个频域上有着更高的精确度。Magnetic bearings can effectively increase the critical speed of high-speed motors,but axial magnetic bearings have a significant eddy current effect at high rotor speeds and solid materials.For the modeling of solid axial magnetic bearings,the eddy current effect is often ignored when using the equivalent magnetic circuit method to establish the axial magnetic bearing model,resulting in a large error between the theoretical model and the actual model.In order to obtain an accurate model of axial magnetic bearings closer to the reality,the axial part of a hybrid 3-degree-of-freedom magnetic bearing was identified,and the determination process and error criteria of the fractional order model were studied.The mathematical model of axial magnetic levitation bearing was derived.The results show that the fractionalorder system model can compensate for the phase characteristic error of the integer-order model in the high frequency band,and has higher accuracy in the entire frequency domain.

关 键 词：高速电机 磁悬浮轴承 三自由度混合型磁悬浮轴承 数学模型 系统辨识 分数阶系统 

分 类 号：TH133.3[机械工程—机械制造及自动化]