【作者】 李晖；

【导师】 陈劭； 徐向波；

【作者基本信息】 北京林业大学 ， 机械专硕（专业学位）， 2024， 硕士

【摘要】 我国目前正处在工业化高速增长期,对于能源的需求与日俱增,由其引起的生态环境问题也愈发突显。高速磁悬浮电机作为新型电动设备,具有能源损耗小、运行效率高、噪声小等优点,在降低生态环境压力、推动“碳达峰”和“碳中和”目标实现等方面发挥着重要作用,同时与当前国家强调的节能增效、绿色发展目标相符合。本文以应用于压缩机的高速磁悬浮电机为研究对象,对电机结构、机械强度、转子动力学等关键问题进行研究分析。(1)根据项目要求确定了10 kW、80000 r/min高速磁悬浮电机的设计方案,并完成了电机定转子、磁悬浮轴承、冷却系统等关键部件的设计与分析。基于力学理论,建立了考虑转速和温升的永磁体-护套结构的应力解析模型,并针对影响机械强度的关键因素展开分析,提出永磁体-护套结构的优化设计方案。利用有限元软件完成了关键部件的电磁性能分析和转子应力分析,仿真结果表明,该电机的电磁性能和机械强度都能满足设计要求。(2)根据该电机转子的结构特点和应用需求,建立了含负载的三段式转子系统的动力学分析模型,考虑了负载对其动力学特性的影响。基于传递矩阵法和有限元法进行了转子系统的临界转速分析。研究结果表明,转子系统的工作转速与临界转速之间满足安全裕度要求。同时,基于国际标准化组织(International Organization for Standardization,ISO)和美国石油学会(American Petroleum Institute,API)关于转子系统振动的相关标准分析了转子系统的不平衡响应情况,结果表明,转子系统振动满足标准要求。此外,分析了轴承刚度、不平衡量大小及加载位置等因素对于转子系统动力学特性的影响,为同类型转子系统动力学性能的改善提供理论参考。(3)完成了高速磁悬浮电机样机的制作和试验平台搭建,对电机运行性能、温升以及转子固有模态进行了试验研究。试验结果显示,电机在空载和负载工况下均能实现稳定运转,且散热效果良好;模态试验和仿真结果的最大误差约为5%,验证了转子系统动力学建模分析的准确性及在工作转速下转子不会出现共振失稳现象。上述研究结果不仅表明了该电机设计的合理性,同时对用于压缩机的高速磁悬浮电机及转子系统的优化设计和动力学分析具有一定参考价值。更多还原

【Abstract】 China is experiencing rapid industrialization growth,accompanied by a daily escalation in energy demand,resulting in increasingly conspicuous ecological and environmental challenges.As a new type of electric equipment,high-speed maglev motors have the advantages of low energy loss,high operating efficiency,and low noise.They are essential in reducing ecological pressure and promoting achieving"carbon peak"and"carbon neutrality"goals.They align with the current national emphasis on energy conservation,efficiency enhancement,and green development goals.This article relies on a school-enterprise cooperation project.It took the 10kW,80000r/min high-speed magnetic levitation motor used in compressors as the research object to study and analyze critical issues such as motor structure design,mechanical strength analysis,and rotor dynamics analysis.(1)According to the project requirements,the design scheme of the high-speed magnetic levitation motor was determined,and the design and analysis of the stator and rotor of the motor,the magnetic levitation bearing,the cooling system,and other vital components were completed.Based on the mechanic’s theory,the stress analysis model of the rotor structure,which considers the rotating speed and temperature rise,was established.The key factors affecting the mechanical strength were analyzed,and the optimal design of the rotor structure was proposed.The finite element software was used to complete critical components’electromagnetic performance analysis and rotor stress analysis.The simulation results show that the motor’s electromagnetic performance and mechanical strength meet the design requirements.(2)According to the rotor’s structural characteristics and application requirements,the dynamic analysis model of the three-stage rotor system with load was established,and the influence of load on its dynamic characteristics was considered.The critical speed of the rotor system was solved using the transfer matrix method and finite element method,respectively.The analysis shows that the operational speed of the rotor system and the first-order bending critical speed meet the safety margin requirements.Additionally,the unbalanced response of the rotor system was analyzed based on ISO and API standards.The results show that the unbalanced vibration of the rotor system is within the allowable range.Furthermore,the influence of the bearing stiffness,the unbalance,and the applied position on the dynamic characteristics of the rotor system were analyzed,offering a theoretical basis for enhancing the dynamic performance of similar rotor types.(3)The high-speed maglev motor prototype manufacture and establishment of the test platform were completed.The operation stability and temperature rise of the motor and the natural mode of the rotor were tested.The test results show that the motor can achieve stable operation under no-load and load conditions,and the heat dissipation effect was good.The maximum error of modal test and simulation results was 5%,which verifies the accuracy of dynamic modeling analysis of the rotor system,and the rotor will not appear to have resonance instability under the working speed.The research results show the rationality of the motor design.They also have a reference value for the optimal design and dynamic analysis of the high-speed magnetic levitation motor and rotor system for compressors.更多还原