基于轴向支撑超声波悬浮高速电机的研究

设计了一种轴向支承电机转子的超声波悬浮支撑结构。采用圆锥型轴承超声悬浮支撑结构,并对承载能力进行了分析和测试,获得了悬浮力与悬浮间隙间的关系,在振动过程中形成稳定的承载气膜;从理论上分析了在超声悬浮支承条件下,悬浮间隙变化对于电机转子临界转速与振动模态的影响情况,对转子最高转速与悬浮间隙的关系进行了实验研究。结果表明,通过减小悬浮间隙,能增强间隙气膜的刚度支承效果,并提高转子的最高转速。     

温度对悬浮浆料黏度的影响

多线切割在光伏以及半导体行业中有着广泛的应用,多线切割所用的悬浮浆料有着非常重要的作用,悬浮浆料由悬浮液和SIC切割微粉配制并长时间搅拌而成,性能优良的悬浮浆料兼有切削、黏滞、冷却3大功能,可以有效提高硅片质量,提高生产效率,研究其特性对于科研生产意义重大,通过对悬浮液特性的研究,进而研究悬浮浆料对切割效果的影响,主要是温度对其的影响,说明在生产中,悬浮浆料要控制在适宜的黏度范围内,才能有效控制晶片质量。     

基于Leap Motion手势识别的悬浮真3D显示实时交互系统

提出基于Leap Motion手势识别的悬浮真3D显示实时交互系统,可实现对多个悬浮3D图像的独立交互.系统由显示和交互两个模块组成,显示模块利用集成成像3D显示屏再现3D图像,再通过二面角反射镜阵列实现悬浮真3D显示;交互模块通过Leap Motion识别手部各关节空间位置,提取手势信息并判断用户操作意图,利用提出的...     

塔上外拉线悬浮抱杆分解组塔方法

在川藏联网工程中,大多数塔位处于高差变化极大的孤山、半山甚至危崖地带,铁塔组立地形条件极差,采用传统的内拉线悬浮抱杆分解组塔和外拉线悬浮抱杆分解组塔很难满足施工需要。针对这种情况,本文提出了塔上外拉线悬浮抱杆分解组塔的方法,并在川藏联网工程组塔施工中成功应用。     

静电悬浮转子微陀螺五自由度位置检测研究

给出了一种基于微机电系统(MEMS)技术的静电悬浮转子微陀螺,为了实现对静电悬浮转子微陀螺转子的五自由度(5-DOF)悬浮控制,需要对转子进行五自由度位置检测,首先介绍了微位移检测原理,提出了一种基于频分复用技术和开关解调技术的微位移检测方法,设计了基于直接数字频率合成(DDS)技术的多频率信号发生器、前置放大器及锁相放大器组成的位置测试系统,位移检测电路的各项性能指标能满足静电悬浮转子微陀螺的五自由度控制需要.     

超声波轴承悬浮性能及承载能力的实验研究

超声波悬浮及减摩技术是一种新型的科学技术。在超声减摩方面我们已经做了大量的研究。文章在此基础上，首次提出超声波振动悬浮轴承的概念。分析对比了普通动压润滑滑动轴承与超声波悬浮轴承；模拟简单的静载推力轴承，并对其悬浮性能和承载能力进行了初步的研究。     

无源电悬浮原理及其实验研究

人们在研究微电机的过程中发现：转子与基底和轴承的摩擦已构成严重影响其运转动态性能的瓶颈障碍，它的转速和寿命远未达到理论值，用电悬浮轴承替代机械轴承不适为一种可选方案，本文对无源电悬浮的稳定平衡条件进行了论证，并作了悬浮过程的动力学模拟，选择直径为３ｍｍ，厚为０．２ｍｍ的玻璃片做悬浮的宏观模拟实验，在仔细调谐电路之后，悬浮物获得六个自由度（ｘ，ｙ，ｚ，θ，ψ）上的鲁棒稳定，进而论证了电悬浮在微机械中应用的可行性。     

单绕组磁悬浮开关磁阻电机低铜耗发电研究

为减小单绕组磁悬浮开关磁阻电发电机(SWBSRG)保持悬浮时绕组的铜耗,以及解决励磁不平衡时续流发电区间悬浮不可控问题,提出了一种新的悬浮发电控制策略。该控制策略可降低悬浮过程中绕组的铜耗。并通过对悬浮、励磁、发电区间的划分和区间时长的推导来解决续流发电区间悬浮不可控问题。通过Simplorer和Maxwell的联合仿真验证了此种低铜耗悬浮发电原理的正确性以及转子径向位移具有较好的悬浮收敛性,并通过反馈控制励磁电流来实现对输出电压的良好控制。     

单颗粒煤粉声悬浮全息测量实验研究

运用数字全息测量技术对声悬浮场中煤粉颗粒的冷态、热态现象进行了实验研究。通过电荷耦合器件(CCD)记录煤粉颗粒的冷热态全息图,应用小波变换对图像进行重建,获得同一煤粉颗粒在不同投影面下的粒径以及空间位置。重点分析了煤粉在CO2激光器照射下,挥发分析出及颗粒破碎现象,挥发分只在竖直方向析出,且主要集中在尖角处。破碎形成的颗粒大小不一,位置比较随机,z轴方向距离较大。通过分析热态时颗粒粒径随时间的变化,获得了颗粒的燃烧速度,同时给出了颗粒z轴位置随时间的变化。实验结果表明数字全息技术可以应用于声悬浮场中煤粉颗粒燃烧时的测量,是研究煤粉燃烧的有力工具。     

高密度硬磁盘用压电复合磁头悬浮臂

针对硬磁盘驱动器中磁头定位两级伺服控制系统,利用宽度弯曲振动模式,设计并制备了分割电极型压电复合磁合悬浮臂。研究了复合磁头悬浮臂的动态位移特性,动态频响特性,以及它对读出信号脉冲幅值的影响。结果表明：２０Ｖ正弦电压激励下可 动态位移幅值约为１μｍ;其固有庇振频率达６．３ｋＨｚ,满足高密度硬磁盘对两级伺服控制系统的基本要求。     

Electrostatic suspension of dielectrics

This paper reports the successful electrostatic suspension of dielectric materials. In order to implement a stable suspension, the electrostatic forces exerted on a dielectric are actively controlled on the basis of the measured suspension gap lengths. The principle of electrostatic force generation for dielectrics is different from that for conductors. By utilizing a stator electrode pattern containing many boundaries over which potential differences exist, the suspension characteristics, such as dynamic stability, suspension initiation time and stiffness of lateral motion are greatly improved. The dynamic model of the suspension system and the influence of the resistivity of a dielectric on the closed-loop stability are described, followed by the experimental apparatus and stabilizing controller. As dielectric objects, glass plates have been suspended electrostatically at a gap length of about 0.3 mm. Apart from the structure of the stator electrode, the suspension initiation time is also influenced by air humidity, glass type, supplied voltage and gap length, which have been experimentally explored. Experimental results on the lateral dynamic characteristics are also presented     

Characteristics of superconductive magnetic suspension and propulsion for high-speed trains

Theoretical analyses are carried out on a magnetic suspension and a linear synchronous motor, both utilizing superconducting magnets. The derived theory is applied to the studies of the high-speed train models. In the suspension system investigated here, the roadbed is equipped with normal conducting coils. The magnetic lift force is found to be pulsating, and a design criterion for eliminating the pulsation components in the lift force is derived. An improved suspension system is proposed, which consists of a "ladder-type conductor" in the roadbed. This new system is investigated theoretically. An end effect of the suspension system is also studied. In the linear synchronous motor, the methods of minimizing reaction forces are derived. The combined magnetic suspension and propulsion system is analyzed. It is found that the influence of the track loops for the suspension on the linear synchronous motor is not very significant.     

Development of gold to gold interconnection flip chip bonding for chip on suspension assemblies

Gold to gold interconnection (GGI) flip chip bonding technology has been developed to bond the drive IC chip on the integrated circuit suspension used in hard disk drives. GGI is a lead free process where the Au bumps and Au bond pads are joined together by heat and ultrasonic power under a pressure head. The use of GGI flip chip assembly process will help to eliminate equipment parts and processing steps of the traditional flip chip C4 process and hence shortens the overall cycle time. With the integrated circuit suspension design, it becomes possible to assemble the drive IC chip close next to the magneto-resistive head slider on the suspension.This paper describes a flip chip bonding method joining the drive IC chip on integrated circuit suspension with GGI bonding. The reliability evaluations are concentrated on thermo-mechanical analysis, robustness and functional performance of the final assembly. GGI bonding for chip on suspension application is still relatively new and has not been achieved for volume use. Work is still being done to establish and extend the limits of the technology with regard to long term reliability.     

Design and analysis of a novel wound rotor for a bearingless induction motor

The traditional squirrel-type bearingless induction motor (BIM) suspension winding generates induced current in its squirrel-cage rotor and affects the phase and amplitude of the suspension force. Based on the analysis of the spatial distribution of torque winding magnetic field and suspension winding magnetic field, a new type of wound rotor BIM is designed. Different from the squirrel-cage rotor, the wound rotor uses a special method of embedding a set of coils at any symmetrical four rotor slot positions, so as to only induce the torque winding magnetic field. The induced current, air-gap magnetic density, magnetic field line distribution, suspension force as well as electromagnetic torque of the traditional squirrel-cage motor and the new wound motor are analysed by Maxwell finite element calculation. The results show that the designed new wound BIM can not only effectively suppress the induced current of suspension winding, eliminating its influence on the suspension force, but also has a better starting performance.     

Integrated tilt with active lateral secondary suspension control for high speed railway vehicles

This paper presents a novel active suspension control configuration for high speed tilting railway vehicles which integrates tilt with active lateral secondary suspension. The use of the active lateral secondary suspension is to attenuate the vehicle body lateral vibration on straight track, while complementing tilt action during curving. Various control strategies are proposed to accommodate both tilt and active lateral suspension multiple design requirements, whilst considering the strong interaction between vehicle body roll and lateral modes. Compared with the commercial solutions for tilt control, the proposed integration strategy improves the tilting control performance both on curved and straight track as illustrated by simulation tests and control assessments based on given track profiles.     

基于有限元分析的直流电机控制策略

无轴承无刷直流电机集成了直流和交流电机的优点,具有重要的实际应用价值,针对传统悬浮力控制方法存在工作复杂、逆变器通断频繁等缺陷,为了提高磁悬浮力的控制效果,提出了基于有限元分析的无轴承无刷直流电机悬浮力控制策略。首先对无轴承无刷直流电机的结构以及悬浮力产生的原理进行了分析,然后采用有限元分析法对电机转矩和悬浮力进行计算,从而实现无轴承无刷直流电机控制,最后采用Matlab/Simulink工具对其性能进行测试与验证。结果表明,本文策略可以提高转子悬浮的稳定性,能够保证无轴承无刷直流电机的正常运行。     

Modeling of Nonlaminated Electromagnetic Suspension Systems

Eddy currents induced within nonlaminated electromagnetic actuators by time-varying magnetic fields have a strong effect on the dynamics and control of electromagnetic suspension systems. This paper examines the modeling of these suspension systems and resolves two important problems: 1) the effect of time-varying flotor position on electromagnetic force production and 2) the proper manner in which to model voltage-mode operation of the suspension. The models developed are explicit functions of actuator material and geometric properties. The investigation focuses on axisymmetric cylindrical electromagnetic actuators. Similar results are provided for nonlaminated actuators with C-core stators. Experimental results are presented that demonstrate the accuracy of the modeling approach.      

An optimal tandem active-passive suspension system for roadvehicles with minimum power consumption

The authors examine the problem of the synthesis of an optimal control law for active suspensions of road vehicles, based on a model with two degrees of freedom. The possibility of realizing the desired optimal control law with a tandem active-passive suspension is considered. The procedure for determining the desired optimal control law on the basis of suitable design specification is outlined. In the case of a suspension with two degrees of freedom, the possibility of realizing a control law with an active suspension in tandem with a conventional passive one consisting of a spring and a damper is examined. The characteristic parameters of the passive part of the suspension are identified with the aim of minimizing the power required by the active part. The expressions for calculating the values of the elastic constant of the spring and of the characteristic coefficient of the damper, which are both assumed to be linear, are provided. An example of the application is presented     

Permanent-magnets linear actuators applicability in automobile active suspensions

Significant improvements in automobile suspension performance are achieved by active systems. However, current active suspension systems are too expensive and complex. Developments occurring in power electronics, permanent magnet materials, and microelectronic systems justifies analysis of the possibility of implementing electromagnetic actuators in order to improve the performance of automobile suspension systems without excessively increasing complexity and cost. In this paper, the layouts of hydraulic and electromagnetic active suspensions are compared. The actuator requirements are calculated, and some experimental results proving that electromagnetic suspension could become a reality in the future are shown.     

基于单轮车辆悬架的Fuzzy-PID控制器设计和仿真

研究车辆主动空气悬架的控制问题,在车辆主动空气悬的常规PID控制器的基础上,运用模糊推理对常规PID控制器进行参数在线修订,设计了基于单轮车辆主动空气悬架的Fuzzy-PID控制器,并对Fuzzy-PID控制的单轮车辆主动空气悬架进行Matlab建模和仿真试验。仿真结果表明,与车辆被动空气悬架、常规PID控制的车辆主动空气悬架相比,Fuzzy-PID控制的车辆主动空气悬架可大大降低车身加速度和悬架动行程,提高车辆乘坐舒适性和操纵稳定性,具有良好的鲁棒性,从而验证了Fuzzy-PID控制器的有效性和实用性。