磁化效应对高速磁悬浮外圆磨削电主轴回转精度影响规律研究  

The Influence of Magnetization Effect on the Rotary Accuracy of a High-Speed Magnetic Levitated Cylindrical Grinding Spindle

作　　者：孙文彪 熊万里[1,2] 原帅 曾旭 汪剑 SUN Wenbiao;XIONG Wanli;YUAN Shuai;ZENG Xu;WANG Jian(National Engineering Research Center for High Efficiency Grinding,Hunan University,Changsha 410082;Guangzhou Haozhi Industrial Co.,Ltd.,Guangzhou 511356)

机构地区：[1]湖南大学国家高效磨削工程技术研究中心,长沙410082 [2]广州市昊志机电股份有限公司,广州511356

出　　处：《机械工程学报》2024年第23期236-245,共10页Journal of Mechanical Engineering

摘　　要：回转精度是高速磁悬浮外圆磨削电主轴的重要性能指标,通常以回转误差来衡量,主要受动不平衡力和轴承特性等因素的影响。铁磁体轴承会因磁化效应输出非线性电磁力,工程上为了实现高回转精度控制,一般通过硬件试验建立查找表对轴承力进行线性化处理。但是当轴承设计变更时,需要重新试验以更新查找表,增加了研发成本和周期。如果能明确磁化效应对主轴回转精度的影响规律,省略试验环节,将有效节省成本和周期。为研究磁化效应对回转精度的影响规律,根据主动磁轴承的基本原理,对无磁化模型、固定磁导模型、Jiles-Atherton(J-A)瞬态磁导模型三种不同磁化模型的电磁力输出特点进行了对比。建立了包含转子动不平衡力、轴承电磁力和磨削力的电主轴刚性转子动力学系统模型。通过系统模型仿真研究了磁化效应对系统闭环幅频特性的影响,发现磁化效应会显著改变系统的低频和中频响应。砂轮中心处回转误差的时域仿真结果表明磁化效应会增大回转误差,固定磁导模型和瞬态磁导模型在偏置电流点附近小范围内的计算结果近似。采用固定磁导模型进行轴承设计,并采用瞬态磁导模型进行验证,是实现磁悬浮磨削主轴高回转精度的可行技术路线。The rotary accuracy is an important performance index of high-speed magnetic levitated cylindrical grinding spindles,usually evaluated through the rotary error,is mainly affected by rotor unbalance forces and bearing characteristics.As the magnetization effect causes ferromagnet bearings to output non-linear forces,in order to achieve high rotary accuracy in engineering applications,the bearing forces are generally linearized by obtaining look-up tables through hardware experiments.However,when bearing design changes,experiments need to be repeated to update the look-up tables,which increases costs and period.If the influence of magnetization effect on the rotary accuracy can be clarified,the experiment might be omitted,and the costs and period can be reduced.Hence,the active magnetic bearing force characteristics of three different magnetization models are compared,such as non-magnetization model,fixed permeability model,and Jiles-Atherton(J-A)transient permeability model.A rigid rotor dynamics spindle system model containing rotor unbalance forces,bearing forces and grinding forces is established.The influence of the magnetization effect on the system closed-loop amplitude-frequency characteristics is investigated through simulation,and it is found that the magnetization effect significantly changes the low and medium frequency system response.The time-domain simulation results show that the magnetization effect increases rotary error.Near the bias current,the output deviation between the fixed permeability model and the transient permeability model is negligible.Using the fixed permeability model for bearing design and the transient permeability model for verification might be an efficient and valuable method to achieve high rotary accuracy for the spindle.

关 键 词：外圆磨削电主轴 回转误差 主动磁悬浮轴承 转子动力学 磁化模型 

分 类 号：TH133[机械工程—机械制造及自动化] TH161[电气工程—电工理论与新技术] TM153