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Effects of mechanical interfaces on magnetic levitation systems and analysis of self-excited vibration mechanisms in coupled systems

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Science China(Technological Sciences) 2024年第12期67卷 3925-3939页

作者： TANG JingHu LI ChaoFeng ZHOU Jin WU ZhiWei School of Mechanical Engineering&Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China Northeastern University Shenyang 110819China School of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 20016China

magnetic levitation is a non-self-stabilizing system that requires high control *** system's stability is affected by the mechanical interface between the levitation object and the loading device,with self-excited vibration generated in the operation *** paper proposes to consider the mechanical behavior of the contact interface in the magnetic levitation *** electromagnetic and control systems are mechanically equivalent,the coupled electric-magnetic-mechanical model is established by adopting the lumped mechanical modeling ***,the effect of the contact clearance on the mechanical behavior of the system is analyzed using the Routh-Hurwitz *** research results show that with the decrease in the contact clearance,the vibration frequency *** the vibration frequency exceeds the critical value,a continuous vibration phenomenon occurs in the system under the joint action of feedback and energy ***,the effect of interface parameters on the vibration characteristics is analyzed using the fourth-order Runge-kutta numerical *** analyses show that the interface contact leads to combination frequency and frequency multiplication components in the coupled system.

关键词： magnetic levitation coupled systems self-excited vibrations mechanical interfaces nonlinear vibrations

Design and Implementation of Digital Fractional Order PID Controller Using Optimal Pole-Zero Approximation Method for magnetic levitation System

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IEEE/CAA Journal of Automatica Sinica 2018年第5期5卷 977-989页

作者： Amit S.Chopade Swapnil W.Khubalkar A.S.Junghare M.V.Aware Shantanu Das IEEE the Department of Electrical Engineering Visvesvaraya National Institute of TechnologyNagpur India-440010India Reactor Control Division Bhabha Atomic Research CentreIndia

The aim of this paper is to employ fractional order proportional integral derivative(FO-PID)controller and integer order PID controller to control the position of the levitated object in a magnetic levitation system(MLS),which is inherently nonlinear and unstable *** proposal is to deploy discrete optimal pole-zero approximation method for realization of digital fractional order *** approach of phase shaping by slope cancellation of asymptotic phase plots for zeros and poles within given bandwidth is *** controller parameters are tuned using dynamic particle swarm optimization(d PSO)*** of the proposed control scheme is verified by simulation and experimental *** performance of realized digital FO-PID controller has been compared with that of the integer order PID *** is observed that effort required in fractional order control is smaller as compared with its integer counterpart for obtaining the same system performance.

关键词： Approximation methods digital control dis-cretization fractional calculus fractional order PID controller(FO-PID) magnetic levitation particle swarm optimization(PSO) position control.

Research on modeling and self-excited vibration mechanism in magnetic levitation-collision interface coupling system

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 873-890页

作者： Jinghu TANG Chaofeng LI Jin ZHOU Zhiwei WU School of Mechanical Engineering&Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems of Ministry of Education of China Northeastern UniversityShenyang 110819China School of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The modeling and self-excited vibration mechanism in the magnetic levitation-collision interface coupling system are *** effects of the control and interface parameters on the system's stability are *** frequency range of self-excited vibrations is investigated from the energy point of *** phenomenon of self-excited vibrations is elaborated with the phase *** corresponding control strategies are briefly analyzed with respect to the vibration *** results show that when the levitation objects collide with the mechanical interface,the system's vibration frequency becomes larger with the decrease in the collision gap;when the vibration frequency exceeds the critical frequency,the electromagnetic system continues to provide energy to the system,and the collision interface continuously dissipates energy so that the system enters the self-excited vibration state.

关键词： magnetic levitation coupling system self-excited vibration mechanical interface vibration frequency

Electromagnetic vibrational energy harvester with targeted frequency-tuning capability based on magnetic levitation

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NANOTECHNOLOGY AND PRECISION ENGINEERING 2024年第4期7卷 16-26页

作者： Hu, Chengbo Wang, Xinyi Wang, Zhifei Wang, Shudong Liu, Yuanyuan Li, Yunjia Southeast Univ Sch Elect Engn Nanjing 210096 Peoples R China Xi An Jiao Tong Univ Sch Elect Engn Xian 710049 Peoples R China Xian Inst Space Radio Technol Xian 710100 Peoples R China

This article presents a compact magnetic levitation energy harvester (MLEH) with tunable resonant frequency. Unlike many of the reported tunable harvesters with unknown tuning results, the proposed MLEH can be tuned toward designated resonant frequency values within its tuning range. The targeted tuning processes is realized by a nonlinear magnet repulsive force exerted on a Halbach magnet array, combined with a calibrated scaling system. At a sinusoidal acceleration of +/- 0.15 g, the maximum frequency tuning range of the proposed MLEH is 6.3 Hz (8.1-14.4 Hz), which is 77.8% of its resonant MLEH (8.1 Hz). At a frequency of 9.7 Hz, the output power is 462.1 mu W and the calculated normalized power density is 496 mu W cm-3 g-2. (c) 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://***/licenses/by/4.0/).

关键词： Electromagnetics magnetic levitation Vibrational energy harvester Frequency tuning Nonlinear system

A novel superconducting magnetic levitation method to support the laser fusion capsule by using permanent magnets

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Matter and Radiation at Extremes 2018年第3期3卷 104-109页

作者： Xiaojia Li Tingting Xiao Fengwei Chen Yingjuan Zhang Xiaofei Li Weidong Wu Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China Science and Technology on Plasma Physics Laboratory Mianyang 621900China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240China Institute of Applied Electromagnetic Engineering Huazhong University of Science and TechnologyWuhan 430074China

A novel magnetic levitation support method is proposed, which can relieve the perturbation caused by traditional support methods andprovide more accurate position control of the capsule. This method can keep the perfect symmetry of the octahedral spherical hohlraum and hasthe characteristics in stability, tunability and simplicity. It is also favorable that all the results, such as supporting forces acting on the super-conducting capsule, are calculated analytically, and numerical simulations are performed to verify these results. A typical realistic design isproposed and discussed in detail. The superconducting coating material is suggested, and the required superconducting properties are *** oscillation of the floating capsule in thin helium gas is discussed, and the restoring time is estimated.

关键词： ICF capsule support magnetic levitation Symmetry

Research on magnetic levitation absolute vibration measurement method in vehicles

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Instrumentation 2014年第2期1卷 38-49页

作者： JIANG Dong SHAN Yi WANG Deyu YANG Jiaxiang College of Electrical&Electronic Engineering Harbin University of Science and TechnologyHarbin 150080C仇加a

This paper presents a design for a magnetic levitation absolute- vibration test system which can be used by vehicles to measure the road surface roughness. The relationship between the vibration test system output voltage and measured speed of the object was obtained through testing,the power spectrum of the measured signal was obtained by virtual instrument analysis,the vibration waveforms of the vehicle over gentle and steep slopes were measured respectively and the road surface roughness was obtained by waveform analysis. Data was saved where the waveforms exceeded threshold. Finally,the steep slope was located using a GPS system. Experimental results show that the magnetic levitation absolute- vibration measurement method has characteristics of high sensitivity and a wide frequency range. This lays the foundation for research into multi- dimensional vibration measurements through magnetic levitation vibration test systems in vehicles.

关键词： magnetic levitation speed sensor flatness power spectrum analysis

A Hybrid High-Tc Superconducting magnetic levitation Sculpture Model

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A Hybrid High-Tc Superconducting Magnetic Levitation Sculptu...

Lateral magnetic stiffness under different parameters in a high-temperature superconductor levitation system

中国材料大会2012

作者： Jun Zheng Hailian Jing Xinglin Liao Dabo He Jifu Chen Suyu Wang Applied Superconductivity Laboratory (ASCLab) Southwest Jiaotong University (SWJTU) Traction Power State Key Laboratory (TPL) Southwest Jiaotong University (SWJTU)

ISBN: (纸本)9783037856079

Different from other applications, this paper explores how to use the stable high-Tc superconducting （HTS） magnetic levitation （maglev） to lift the sculpture art to a high levitation position for satisfying the artist’s requirement for the light artistic concept. With a combination of the permanent magnet （PM） levitation and HTS maglev technologies, a sculpture model was built to sustain a stable levitation with a levitation height of over 80 mm. In this hybrid HTS maglev sculpture model, three PM rings are arranged as upper, middle, and bottom as a double-layer axial levitation structure;six rectangular YBaCuO bulks are fixed along the side of the PM rings’ upper-layer as a stabilizer component along the radial direction. When the bottom PM ring was driven up by the lifting bolt, the upper PM ring, which was fixed with the art, can be lifted much higher. Then the required artistic effect will be enhanced. After the model was designed and optimized by finite element method, it was experimentally validated by the HTS maglev measurement system. This levitation design is helpful to the realization of a real-scale levitation sculpture art, and can also provide references to superconducting radial magnetic bearing systems.

关键词： High-temperature superconductor magnetic levitation Permanent magnet YBaCuO bulk.

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Chinese Physics B 2021年第7期30卷 515-525页

作者： Yong Yang Yun-Yi Wu School of Mechano-Electronic Engineering Xidian UniversityXi'an 710071China China Three Gorges Science and Technology Research Institute Beijing 100036China Physikalisches Institute B RWTH AachenAachen 52056Germany

magnetic stiffness determines the stability of a high-temperature superconductor(HTS)magnetic levitation *** quantitative properties of the physical and geometrical parameters that affect the stiffness of HTS levitation systems should be identified for improving the stiffness by some effective *** magnetic stiffness is directly related to the first-order derivative of the magnetic force with respect to the corresponding displacement,which indicates that the effects of the parameters on the stiffness should be different from the relationships between the forces and the same *** this paper,we study the influences of some physical and geometrical parameters,including the strength of the external magnetic field(B0)produced by a rectangular permanent magnet(PM),critical current density(Jc),the PM-to-HTS area ratio(α),and thickness ratio(β),on the lateral stiffness by using a numerical approach under zero-field cooling(ZFC)and field cooling(FC)*** the first and second passes of the PM,the lateral stiffness at most of lateral positions essentially increases with B0 increasing and decreases withβincreasing in ZFC and *** largest lateral stiffness at every lateral position is almost produced by the minimum value of Jc,which is obviously different from the lateral force–Jc ***α-dependent lateral stiffness changes with some parameters,which include the cooling conditions of the bulk HTS,lateral displacement,and movement history of the *** findings can provide some suggestions for improving the lateral stiffness of the HTS levitation system.

关键词： high-temperature superconductor magnetic levitation lateral stiffness lateral force

Current-Bounded Commutation of a Long-Stroke magnetically Levitated Stage with Moving Coils

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1238-1244页

作者： ZHU Yu ZHANG Shengguo YANG Kaiming MU Haihua YIN Wensheng Department of Precision Instruments and Mechanology Tsinghua UniversityBeijing 100084China

magnetically levitated stages（MLS） have potentials to obtain good motion performances in high vacuum environment. Yet the electromagnetic forces/torques corresponding to six degrees of freedom（DOF） motions have coupling relationship with each current of coil array, and this coupling is still associated with the relative positions between the mover and the stator of the stage. So it is quite difficult to control the 6-DOF motions of the stage. By reasonable commutation of coil array, this complicated coupling relationship can be decoupled. The analytical force/torque-decomposing model of the stage is established first. Then the initial currents of coil array are commutated based on the pseudo inverse of the analytical force/torque-decomposing model matrix. And then the coil array currents are commutated again with different current bounds given to the initial currents as well as in the sense of minimum 2-norm of currents vector. Using the long stroke magnetically levitated stage with moving coils under investigation as examples, the currents of coil array are commutated with different current bounds adopting the proposed commutation method, the determination of current bound and the current bounds＇ influences on the heat-losses in coil array are analyzed, and the effectiveness of implementation algorithm of proposed commutation method is discussed. Simulation, analysis and discussion results indicate that the currents of coil array within the given current bound can be solved analytically by proposed commutation method, and the implementation algorithm does not need any searching or iteration. By the current-bounded commutation method proposed, the amplitude of coil array currents can be limited within an appropriate current bound（This is very beneficial to the improvement of the reliability and motion performance of the stage）, as well as these currents can also generate the desired forces and torques.

关键词： magnetic levitation current-bounded commutation current bound coil array electromagnetic forces/torques heat-loss.