基于DSP2812的磁悬浮轴承位移检测控制系统设计

针对磁悬浮轴承系统位移检测的特点,设计了一套以TMS320F2812 DSP为核心的磁悬浮轴承位移检测控制系统.详细介绍了电涡流位移传感器的工作原理,设计了磁悬浮轴承系统的数字控制器、位移信号调理电路等相关硬件电路,并对所设计的位移检测数字控制系统进行了软件实现,给出了主程序和中断子程序流程图,最后,对所设计的磁悬浮轴承位移检测数字控制系统进行了试验验证.     

欠传感器磁悬浮转子测量系统的设计与研究

在磁悬浮转子系统的应用中，位移传感器的个数与布置是系统设计的一个重要课题。在此分析了磁悬浮转子应用系统的传感器空间布置的问题。提出了欠传感器磁悬浮转子系统的设计思想。并具体给出了一个欠传感器磁悬浮转子系统的测控方案。对欠传感器磁悬浮系统在三维空间的测量信号进行了研究，实现了测量信号各个分量的解耦与分离。     

磁悬浮转子系统中涡流传感器的工作特性研究

根据涡流位移传感器的工作原理及其在磁悬浮转子系统中的应用,介绍磁悬浮转子的工作环境以及对传感器的影响,分析涡流传感器在变化磁场环境下的误差来源以及表现形式,设计实验并测试了涡流传感器在变化磁场环境中的工作特性。实验结果表明:磁力轴承的变化磁场以及磁滞特性也是影响涡流传感器测量精度的一个重要原因,磁悬浮转子检测系统需要考虑磁场环境对测量精度的影响,对进一步提高磁悬浮转子的控制精度具有重要的参考价值。     

轴向磁悬浮轴承用非接触式差动电感位移传感器的实验研究

介绍了轴向磁悬浮轴承系统的结构及其与位移传感器的关系,以及非接触差动电感位移传感器的基本构成和性能;讨论了这种位移传感器在电磁轴承系统中应用的特点及可行性,并在此类传感器的试验装置上做了其静特性分析实验,给出了部分实验结果。     

磁悬浮飞轮用可重复电磁锁紧装置的设计与试验

针对磁悬浮飞轮用基于机构自锁原理的可重复电磁锁紧装置,分析其原有显式电磁铁执行机构的电磁力学特性,得知其最小解锁残余力过大,若采用隐式电磁铁,可以消除解锁残余力,从而提高锁紧装置解锁可靠性。采用等效磁路法对隐式电磁铁进行磁路分析,并给出该电磁铁在执行锁紧、保持锁紧、执行解锁和保持解锁四种状态下的力学模型。利用电磁场数值分析法,对隐式电磁铁进行实例设计,并通过卫星发射过程中的正弦扫频振动和随机振动试验,检验改进后的锁紧装置对飞轮系统的保护效果。结果表明,锁紧装置的最小解锁残余力为0.25 N,远小于原有显式电磁铁方案(29.5 N),且振动测试中,飞轮定、转子的最大相对振动位移为70μm,最大位移振幅为10μm,都小于磁悬浮飞轮系统的保护间隙100μm。改进后的隐式电磁铁在提高解锁可靠性的同时,可有效地实现对飞轮系统的锁紧保护功能。     

位移传感器在磁悬浮电主轴中安装结构的改进

位移传感器在径向的安装结构是否合理,直接影响磁悬浮电主轴的控制精度。探讨了位移传感器在磁悬浮电主轴中几种不同的安装方式,并设计了一种新的安装结构。实验证明:该结构设计合理、工作可靠。     

集成式径向磁轴承用差动位移传感器的设计

介绍了差动位移传感器的工作原理,在此基础上,提出了一种集成式径向磁轴承专用传感器的结构,给出了基于AD598芯片为核心的位移信号处理电路设计方法,并试验了单自由度的静态性能以及同结构双自由度间信号耦合的静态性能分析。结果表明：文中介绍的集成式径向差动位移传感器的性能可以满足磁悬浮系统工作的要求。     

差动变压器式位移传感器及其在磁悬浮轴承中的应用

针对差动变压器式位移传感器的性能及其在磁悬浮轴承中的应用,理论分析传感器与磁悬浮轴承转子之间加入不同隔层时对传感器输出的影响;对传感器进行静态和动态标定,并将其应用于2自由度和5自由度磁悬浮轴承试验台进行静态和动态悬浮。研究结果表明：该传感器测试范围在–0.5～＋0.5 mm时,线性度可达±1.38%,灵敏度为20.18 mV/μm,截止频率在800 Hz左右;理论分析加入非导磁隔层不影响传感器性能,但实际中涡流、漏磁等多方面原因将影响传感器的静动态性能;在2自由度试验台上实现磁悬浮转子2自由度的静态悬浮,不加入隔层时转子的静态位移振动峰峰值小于5 μm,加入隔层时转子的静态位移振动峰峰值小于10 μm;在5自由度试验台上实现了磁悬浮转子的高速旋转,转速为30 kr/min,不加隔层时转子两端的径向振动峰峰值为25 μm,加入隔层时转子两端的径向振动峰峰值为25 μm,但波形没有不加隔层时规则。研究结果为差动变压器式位移传感器的设计,并将其应用于磁悬浮轴承系统中提供一定的理论和试验基础。     

电磁驱动磁悬浮进给机构研究

设计了一种新型电磁驱动磁悬浮进给机构,将电磁铁与导磁体静平衡位置交错,使其不仅产生悬浮力,而且还可利用此交错位置产生的复原力为驱动力,简化了结构设计与控制环节。分析了磁悬浮吸力及驱动力,在保证驱动力为最大的前提下,确定出电磁铁初始位置,并通过优化计算,给出了只与工作台质量有关而与其几何尺寸无关的电磁铁结构参数。     

磁悬浮轴承系统的模型辨识与控制

对某磁悬浮轴承系统进行了理论建模,并进行了试验。由于建模时忽略了功率放大器和位移传感器的影响,磁悬浮轴承系统理论模型与其实际特性有较大差异,磁悬浮轴承系统是一个三阶模型,而非理论模型的二阶模型,基于理论模型设计的控制器难以获得较好的控制性能,建模时需考虑功率放大器和位移传感器的影响。为优化控制性能,采用频域辨识法对实际系统进行模型辨识,得到系统的频率特性,并对辨识数据进行模型拟合。在辨识得到的三阶模型基础上,采用极点配置法重新设计控制器,对转子进行悬浮控制,转子稳定悬浮时的位移波动量降低了约60%。     

汽轮机DEH伺服控制系统阀门位移反馈方式的探讨

根据伺服系统安全设计和LVDT冗余设计原则提出了双通道低选位置反馈方式和提高伺服机构可靠性的冗余设计方案,大大减小因阀位反馈信号故障而使伺服机构误动作的可能性,从而提高伺服机构动作的可靠性.     

Miniaturization of a one-axis-controlled magnetic bearing

The design of a novel micro-magnetic bearing (MMB) for a 2-mm-diameter rotor is discussed. The bearing is supported by magnetic couplings generated by permanent magnets and is stabilized by a one-axis controller. The structure of the MMB is greatly simplified, not only in terms of machining and assembly of micro- and precision parts, but the number of mechanical parts is also reduced in comparison with previous designs of MMB. To increase the magnetic stiffness used to support the rotor in the passively controlled directions and to realize stable levitation using one-axis control, the dimensions of the mechanical parts that affect the magnetic stiffness are investigated using a finite element method. An MMB for a 2-mm-diameter rotor was constructed, such that the rotor could be levitated without mechanical contact and which rotated at 39,000 rpm. The static and dynamic characteristics of the MMB are evaluated, including magnetic stiffness, rotational accuracy and power consumption.     

基于CAN总线的机车微机控制系统研究

文章根据现有机车操纵控制系统的功能和控制方式,确定CAN总线作为其设备级控制总线．依据计算机网络操作系统的设计思想．对控制系统网络进行了总体设计,提出了一种网络冗余的方案,并进行了应用层程序的设计,实现了网络即插即用,冗余、自检、数据收发等功能．     

Compensation of rotor imbalance for precision rotation of a planar magnetic bearing rotor

Magnetic bearings provide an alternative for achieving precision rotation. But the rotational accuracy is sensitive to rotor imbalance. The system we study is a planar rotor supported by aerostatic suspension and positioned by a radial magnetic bearing of nanometer precision. We present compensation designs and experiment results for precision rotation about the geometric center and the mass center, respectively. In the former case, the base harmonic component at each sensor output is removed by explicit trigonometric compensation signals that are constructed in real time. In the latter case, a new double-loop compensation design is given. Each compensation loop is similar to that in the former case. The compensation, aided by a variable rotational speed that is changed up and down repeatedly, is shown to push the rotational center to approach the mass center. Once the mass center is reached, the rotor remains to rotate about the mass center at variable rotational speed without transient. Compared with the existing methods, which find the mass center or inertial axis at a fixed rotational speed and rely on exact values of plant parameters, our method may locate the mass center more accurately. Experiment data indicate that the mass center is located with an error of tens of nanometers.     

基于CAN总线的混合动力公交客车控制系统设计

针对混合动力公交客车,本文提出一种依据系统功率，确保柴油发动机转速、运行工况相对稳定,兼顾柴油发动机经济性、排放性的串联式控制系统的控制策略．确定选用CAN总线作为其控制网络。对控制网络结构进行了总体设计，在此基础上提出了一种网络冗余的设计方案，保证了数据传输的可靠性，并进行了应用层程序的设计,实现了网络冗余、自检、数据收发的功能。     

遗传算法在串-并联冗余系统可靠性优化设计中的应用

串-并联冗余系统可靠性的最优设计是可靠性技术中一个十分重要的问题。讨论了遗传算法及其在串-并联冗余系统可靠性优化设计中的应用。串-并联冗余系统具有冗余单元和可选设计，其可靠性优化设计是一高度非线性、具有多极值点、有约束的整数规划问题，传统的解决方法往往对于连续实数域有效可行，而对于解决此类多变量，离散型整数域取值的复杂的优化问题则往往很困难。由于遗传算法是一类全局收敛算法，它用点群进行寻优，而不是用一个单点进行寻优，具有隐含并行算法的特点，从而能够得到全局最优解。所给出的实例说明本文的算法是有效可行的。     

精密注塑模具的注塑成型模拟

在精密注塑模具设计过程中应用计算机辅助分析的方法模拟注塑成型过程,对保证注塑成型产品的质量,提高生产率有极大的优越性。利用MoldflowPlasticInsight(MPI)软件对精密注塑模具的注塑成型过程进行了模拟,分别介绍了注塑参数、浇注系统和冷却系统的设计过程,比较了两套不同设计方案的注塑成型模拟结果。并对影响翘曲变形的各个因素进行了详细的分析。     

基于冗余技术EPB盾构同步注浆控制系统设计

详细阐述了冗余控制技术原理及特点,以提高盾构自动控制系统可靠性为目的,基于硬件冗余控制技术开展土压平衡(EPB)盾构同步注浆控制系统软件的控制回路流程分析,关键控制算法设计,并对同步注浆系统的控制条件的关联性和控制回路流程进行分析研究。通过室内实验对上述设计进行验证、总结。对硬件冗余控制技术在盾构自动控制系统中应用前景进行了展望。     

Studies about the use of semicircular beams as hinges in large deflection planar compliant mechanisms

Conventional hinge designs in planar compliant mechanisms have a limited deformation range because of the high stresses induced during deflection. To improve the range of motion of these mechanisms, hinges that allow for large displacement are highly desirable. This paper explores the use of curved beams as large displacement hinges in planar compliant mechanisms. To facilitate design, analytic expressions that predict deflections under different types of loads are introduced. These expressions are used in pseudo rigid link models of compliant mechanism designs. Predictions made by the analytic expressions are compared with the results of FEA simulations. To validate the proposed models, two planar compliant mechanism designs were prepared and experimental measurements of deflections under loads were made. Overall, results showed that analytic models and FEA predictions lie within 10% of experimental data for the planar mechanism geometry in which pseudo rigid motion models apply. FEA models of the second case, a more complex mechanism, make predictions that lie within 15% of experimental measurements. Results and ways to improve accuracy of models and designs are discussed at the end of the article.     

Design and precision construction of novel magnetic-levitation-based multi-axis nanoscale positioning systems

This paper presents two novel six-axis magnetic-levitation (maglev) stages capable of nanoscale positioning. These stages have very simple and compact structures, which is advantageous to meet the demanding positioning requirements of next-generation nanomanipulation and nanomanufacturing. Six-axis motion generation is accomplished by the minimum number of actuators and sensors. The first-generation maglev stage, namely the Δ-stage, is capable of generating translation of 300 μm and demonstrates position resolution better than 2 nm root-mean-square (rms). The second-generation maglev stage, namely the Y-stage, is capable of positioning at a resolution better than 3 nm rms over a planar travel range of 5 mm × 5 mm. A novel actuation scheme was developed for the compact structure of this stage that enables six-axis force generation with just three permanent-magnet pieces. This paper focuses on the design and precision construction of the actuator units, the moving platens, and the stationary base plates. The performance of the two precision positioners is compared in terms of their positioning and load-carrying capabilities and ease of manufacture. Control system design for the two positioners is discussed and an experimental plant transfer function model is presented for the Y-stage. The superiority of the developed instruments is also demonstrated over other prevailing precision positioning systems in terms of the travel range, resolution, and dynamic range. The potential applications of the maglev positioners include semiconductor manufacturing, microfabrication and assembly, nanoscale profiling, and nanoindentation.