【作者】 刘平凡；

【导师】 富宏亚；

【作者基本信息】 哈尔滨工业大学 ， 机械制造及其自动化， 2013， 博士

【摘要】 神光III是我国在建的激光惯性约束核聚变工程，其中终端光学组件作为惯性约束核聚变中激光光路传输的末端装置，承担着频率转换、谐波分离和光路聚焦等功能。其核心元件KDP晶体镜片工作环境必须为高洁净和超高真空的大型密闭容器，要求无油和无碳氢化合物等污染，且工作真空度<1×10-8Pa，极限真空度甚至要达到1×10-9Pa。为了满足神光Ⅲ终端光学组件模块高真空、高洁净环境的要求，研制了磁悬浮复合分子泵作为达到高真空、高洁净环境的主要装置，采用无物理接触和无需润滑的磁轴承系统，融合涡轮叶片结构和多螺旋槽牵引结构，实现了无油蒸汽返流以及无其它碳氢化合物污染，对额定工作转速高于其刚性临界转速、转子大转速范围内稳定性、高速运转时陀螺效应对系统稳定性的影响、结构模态和高阶挠性模态振动的抑制、系统基座振动等问题进行分析研究，设计了磁悬浮复合分子泵结构和及其控制器。磁悬浮复合分子泵系统的研制为神光Ⅲ工程实现达标奠定了坚实的基础。依据神光Ⅲ终端光学组件对高真空高洁净环境的要求，确定磁悬浮复合分子泵的技术参数，对其总体结构进行了设计和分析；根据涡轮叶片结构和多螺旋槽牵引结构的工作原理，分别设计多级涡轮叶片和多螺旋槽牵引的结构和参数；利用Fluent软件分别对设计的多级涡轮叶片和多螺旋槽牵引结构进行了流场流态分析，对抽气通道内的流动规律进行了数值模拟，重点分析了多螺旋槽结构参数与抽速的关系，仿真结果为其结构设计和优化提供基础。其结果证明在磁悬浮复合分子泵结构设计中结合流场数值模拟可以节约设计成本，成为今后其结构设计的主要方法。根据磁轴承系统工作原理对磁悬浮复合分子泵的径向和轴向磁轴承机械结构进行设计和改进；针对磁悬浮复合分子泵高转速、支撑刚度可变、陀螺效应较强的特点以及薄叶片的结构特征，建立磁悬浮复合分子泵磁轴承支撑叶片转子系统模型，通过有限元软件对叶片转子系统进行模态分析分析了叶片转子系统的模态频率和模态振型，对叶片转子系统高转速下出现频率分叉现象进行分析，为控制器设计提供了理论基础。以磁悬浮复合分子泵叶片转子系统为对象建立系统控制模型，并以此为研究对象进行分散PID控制器设计以满足转子稳定悬浮和正常运转；设计交叉反馈控制器对转子陀螺效应进行抑制，通过Matlab软件进行仿真分析验证控制器的有效性；为了避免激发转子结构模态和挠性高频模态的振动，设计陷波滤波器；为了顺利到达叶片转子额定工作转速，解决转子大范围不稳定和转子过刚性临界转速的问题，设计了变增益自适应控制器；为了抑制磁悬浮复合分子泵转子同频振动和基座振动，设计不平衡补偿控制器。利用设计的变增益自适应控制器和不平衡补偿控制器对磁悬浮复合分子泵系统依次进行了转子静态悬浮、陀螺效应抑制、不平衡补偿控制和高速旋转实验测试。实验结果表明磁悬浮复合分子泵系统在变增益自适应控制器和不平衡补偿控制器共同作用下，不仅能实现顺利超越转子刚性临界转速的要求，而且能够克服转子陀螺效应的影响和抑制转子挠性模态频率，大幅度降低了系统基座的振动，具有较强的自适应性和鲁棒性，额定工作转速可达24000rpm，额定工作转速下转子最大径向振动小于7.8μm，转子可在0~24000rpm转速范围内任何频率处稳定运转。验证了变增益自适应控制器和不平衡补偿控制器的有效性和实用性，验证了磁悬浮复合分子泵转子系统机械结构设计和模态分析的有效性和实用性，积累了磁悬浮复合分子泵转子系统设计、调试和运行的经验。磁悬浮复合分子泵系统转子转速、转子振动和稳定性等性能指标已经能够基本满足神光Ⅲ终端光学组件模块高真空、高洁净环境对其的要求，整体性能居于国内领先水平。更多还原

【Abstract】 Shenguang III is a large engineering project under construction for laser-driveninertial confinement fusion (ICF), of which end optical components are used as theend equipment in laser path to perform functions, such as transforming frequency,separating harmonic and laser focusing etc. The critical component is crystal KDPlens which must work in closed vessel of high clean and vacuum with no oil andhydrocarbon. The normal requirement of vacuum degree is less than1×10-8Pa, evenbelow1×10-9Pa. In order to meet the strict requirement of high vacuum and clean,magnetically suspended compound molecule pump is studied in this dissertation.Turbine blade, multi-spiral groove traction structure and magnetic bearing systemwhich has such advantages as non-contact and no lubrication, are adopted to avoidthe pollution of oil and hydrocarbon. Additionally, the rigid critical speed higherthan normal work speed, the stability of wide rotational speed of rotator, the systemstability of gyroscopic effect in high speed, structural-mode and the suppression ofhigh order of torsion vibration mode, the vibration of system base andelectromagnetic noise are analyzed respectively. At last, the magnetically suspendedcompound molecule pump and its controller are developed, which lay a solidfoundation for the success of Shenguang III project.Based on the requirement of high vacuum for end optical component inShenguang III, the parameter of the magnetically suspended compound moleculepump is determined and the whole analysis is performed for overall structure. Thearguments of multilevel turbine blade and multispiral groove are designedindividually based on the mechanism of turbine blade and multispiral groove. Theflow pattern analysis of flow field is performed for multilevel turbine blade andmultispiral groove in Fluent software. The numerical simulation of flow law isanalyzed for bleed-off passage. The relationship between the geometrical parameterof multispiral groove traction structure and the performance of air exhaust is alsoanalyzed. These simulated results provide a foundation for designing and optimizingstructure. The magnetically suspended compound molecule pump with thesimulation of flow field is demonstrated to cut the price, which becomes asignificant approach for the design of structure.Based on the mechanism of magnetic bearing, the radial and axial magneticbearing physical construction of the magnetically suspended compound moleculepump is designed and improved. Based on the magnetically suspended compoundmolecule pump characteristics of the high speed, metabolic support stiffness andgyroscopic effect and infinitely thin blade, the blade rotor systematic model of the magnetically suspended compound molecule pump is established, which issupported by magnetic bearing. The modal analysis is performed for blade rotorusing the finite element software, thus the modal frequency and modal shape isobtained. Additionally, the phenomenon of frequency bifurcation of blade rotor inhigh speed is analyzed. These will provide a theoretical foundation for the design forcontroller.To control the magnetically suspended compound molecule pump blade rotor,discrete PID controller is investigated to meet the levitation stability and normalrotation for rigid rotor. The constraint of gyro effect is analyzed based on crossfeedback controller and the validity of the controller is demonstrated based on thesimulation using Matlab software. In order to avoid the vibration of structure modaland bending resistance high frequency mode, the notching filter is developed.Variable gain adaptive controller is designed to solve the problem of wideinsatiability of rotor and critical speed of superabundant stiffness for the normalrotational speed of blade rotor. Under the control toward vibration of samefrequency and support of magnetic levitation compound molecule pump andelectromagnetic noise, the non equilibrium compensation controller is developed.To verify the feasibilty and correctness of designed variable-gain adaptivecontroller and imbalance compensating controller, experiments including rotor staticsuspension, the constraint of gyroscopic effect, the compensation of control forimbalance, and high speed rotation are carried out. The result shows that themagnetically suspended compound molecule pump system can not only satisfyingthe requirement of surpassing the rigid critical speed of rotor, but also can overcomeinfluence of gyroscopic effect of rotor and restrain the flexible modal frequency ofrotor. At the same time the blade rotor of the magnetically suspended compoundmolecule pump can rotate around its principle inertia axis, thus the pedestalvibration and electromagnetic noise of the system can be decreased. The controlsystem can have great self-adaptability and robustness. The maximum radialvibration of the rotor is less than10μm on the rated speed which can achieve24000rpm. The rotor can rotate steadily on any frequency in the speed range of0~24000rpm. The experiment verified the validity and practicability of variable-gainadaptive controller and imbalance compensating controller, and verified indirectlythe validity and practicability of the magnetically suspended compound moleculepump system’s mechanical structure design and modal analysis. The experimentaccumulated the experience of design, test and operate for the magneticallysuspended compound molecule pump system. The performance of rotor speed, rotorvibration and stability of the magnetically suspended compound molecule pump isable to satisfy the circumstance of high vacuum and clean for the end opticalcomponent module in shenguang III. And the overall performance of this pump is in the domestic leading level.更多还原