【作者】 赵海涛；

【导师】 夏阳；

【作者基本信息】 大连理工大学 ， 车辆工程， 2024， 硕士

【摘要】 永磁轴承以其结构简单、运行可靠等优点,在电动汽车驱动电机、高速飞轮储能、船舶推进系统以及风力发电机等多个领域展现了广阔的应用前景。本文针对吸力型和斥力型的径向永磁轴承进行研究,分析了其磁力特性及对轴承性能的影响,并研究了漏磁防护措施,旨在进一步提升永磁轴承的磁力效率和工作安全性,以满足现代工业对于高性能、环境友好型永磁轴承不断增长的需求。本文首先研究了永磁轴承的设计方法,对永磁材料、磁化方向、磁钢堆叠结构等开展研究,并比较了不同类型磁轴承的特点及其应用领域。通过分析永磁轴承的结构和工作原理,对四种不同径向磁力计算方法即磁路法、等效磁荷法、麦克斯韦应力张量法和有限元法进行了对比研究,并采用等效磁荷法建立了单环磁力的数学模型。针对漏磁防护问题,引入磁介质理论研究漏磁防护,并对漏磁防护措施进行了详细讨论。随后,研究径向吸力型永磁轴承,通过采用磁套替代内磁环的设计简化了轴承结构,并基于磁路分析方法,根据承载力以及防漏磁要求对现有结构进行了改进。提出了多层磁轭防漏磁径向吸力型永磁轴承,经比较,其磁通密度在漏磁要求关键区域的最大值明显降低,满足了磁场的安全限制要求。进一步地,研究了径向斥力型永磁轴承,建立了其磁力的数学模型,通过蒙特卡洛方法对磁力进行计算,并结合等分序列的蒙特卡洛法和多层蒙特卡洛法,提高了磁力计算的效率。通过与有限元分析及文献结果的对比,验证了这些算法的精确性和实用性。继而,综合分析了多种影响径向承载能力的因素,并对斥力型永磁轴承进行漏磁分析。最后,本文对径向斥力型永磁轴承的设计进行了优化,对磁路结构进行了改进,设计出一种新型的上吸下斥永磁轴承。验证结果表明,该结构不仅提供了更高的径向磁力,而且显示出更优的抗扰动特性,能在内磁环受到外界振动引起的位移时保持磁力的稳定。本文对径向永磁轴承的磁力特性和漏磁防护进行了理论分析和仿真模拟,并对磁力轴承进行了优化设计,为径向永磁轴承的工程应用提供了理论和仿真方法。更多还原

【Abstract】 Permanent magnetic bearings have advantages such as their simple structure and reliable operation,therefore have shown broad application prospects in various fields such as electric vehicle drive motors,high-speed flywheel energy storage,ship propulsion systems,and wind turbines.This thesis focuses on the research of attraction-type and repulsion-type radial permanent magnetic bearings,analyzes their magnetic characteristics and their impact on bearing performance,and investigates measures for leakage magnetic protection.The aim is to further enhance the magnetic efficiency and operational safety of permanent magnetic bearings,in order to meet the growing demand in modern industries for high-performance,environmentally friendly permanent magnetic bearings.This thesis first investigates the design methods of permanent magnetic bearings,conducting research on various type of permanent magnetic materials,magnetic orientation,magnetic steel stacking structures,etc,and compares the characteristics of different types of magnetic bearings and their application areas.By analyzing the structure and working principles of permanent magnetic bearings,a comparative study of four different radial magnetic force calculation methods,namely magnetic circuit method,equivalent magnetic charge method,Maxwell stress tensor method,and finite element method,is conducted.The mathematical model of single-ring magnetic force is established using the equivalent magnetic charge method.In addressing the issue of leakage magnetic protection,magnetic medium theory is introduced to study leakage magnetic protection,and detailed discussions on leakage magnetic protection measures are provided.Subsequently,this thesis focused on the radial attractive type permanent magnetic bearing.The bearing structure was simplified through the innovative design of replacing the inner magnetic ring with a magnetic sleeve.Based on magnetic circuit analysis,factors affecting bearing capacity,and a perspective on preventing magnetic leakage,improvements were made to the existing structure.The proposed multi-layer yoke anti-magnetic leakage radial attractive type permanent magnetic bearing,upon comparison,showed a significant reduction in the maximum value of magnetic flux density in specific areas,meeting the safety limits for static magnetic fields.Furthermore,taking the radial repulsive type permanent magnetic bearing as an example,a mathematical model of its magnetic force was established using a numerical calculation method based on the equivalent magnetic charge method.By employing the Monte Carlo(MC)algorithm,and in combination with the Quasi-Monte Carlo(QMC)and Multi-Level Monte Carlo(MLMC)methods,the uniform distribution of sample points was improved.The accuracy and practicality of these algorithms were verified through comparison with finite element analysis and literature results,significantly enhancing computational efficiency.Subsequently,this paper optimized the design of the permanent magnetic bearing,conducting a comprehensive analysis of various factors affecting radial bearing capacity.Improvements were made to the magnetic circuit structure based on different magnetization methods,resulting in the design of a new type of upper-attractive and lower-repulsive permanent magnetic bearing.Verification results showed that this structure not only provides higher radial magnetic forces but also exhibits superior disturbance resistance characteristics,maintaining magnetic force stability when the inner magnetic ring is displaced due to external vibrations.This thesis provides a theoretical analysis and simulation of the magnetic characteristics and leakage magnetic protection of radial permanent magnetic bearings.It also conducts optimization design of magnetic bearings,offering theoretical and simulation methods for the engineering application of radial permanent magnetic bearings.更多还原