服装裁剪机的步进电机细分控制系统

针对服装裁剪机中步进电机的运动控制问题,基于LPC2138和L6207设计了步进电机细分控制系统,实现了对步进电机的高精度细分控制。实验结果表明,步进电机可以在细分控制系统的控制下稳定、准确的运行,满足了服装裁剪机的精度要求。     

步进电机细分驱动电磁转矩分析

步进电机运行时存在低频振荡、高频容易失步等缺点,采用细分驱动方法可以有效提高步进电机的运行性能.步进电机的运行性能主要由电磁转矩决定.为了研究细分数对步进电机细分驱动运行性能的影响,推导了电磁转矩随细分数变化的函数关系式.通过对步进电机细分驱动与整步驱动时瞬时电磁转矩、总有效转矩及总有效转矩的方差的比较分析,得出了细分驱动可使步进电机总有效电磁转矩增加、转矩波动幅度减小、转矩波动频率增大等结论,细分驱动可提高步进电机的运行效率和平稳性,克服步进电机运行时的共振现象.研究结果表明步进电机细分驱动能够有效地克服低频振荡、高频失步等缺点,扩大了步进电机的应用范围,具有实际应用价值.     

基于DSP的步进电机细分控制系统的设计

为了实现基于DSP的步进电机的细分控制系统,本文首先简述了两相混合式步进电机的细分控制原理,给出了步进电机的驱动接口电路.给出了DSP实现细分控制部分的关键程序代码,实验证明,采用此方案实现步进电机的细分可行有效.     

基于单片机的步进电机细分控制系统

步进电机细分技术主要用于提高电机的运转精度,实现步进电机步距角的高精度细分。通过对步进电机细分驱动原理的分析,合理选择细分电流波形,以AT89C51单片机为核心,结合步进电机驱动芯片L 297/298,设计出步进电机的斩波恒流细分驱动控制系统。并在实际运行过程中运行良好。     

基于FPGA的步进电机均匀细分驱动器的实现

在对步进电机细分驱动原理进行分析研究的基础上,提出一种基于FPGA控制的步进电机细分驱动器.利用FPGA中的嵌入式EAB构成LPM-ROM,存放步进电机各相细分电流所需的PWM控制波形数据表,并通过FPGA设计的数字比较器,同时产生多路PWM电流波形,实现对步进电机转角进行均匀细分控制.     

风动涡轮步进电机细分驱动微机控制调速系统

介绍了风动涡轮步进电机细分驱动微机控制调速系统应用场合、背景及其有关技术;详细介绍了系统组成原理及技术关键;重点描述了步进电机细分驱动和微机控制的涡轮调速器;从理论上阐明步进电机细分驱动是提高步进电机分辨率和消除低频振荡的有效办法,作者提出的定频脉宽调制细分驱动很好解决了效率低的技术问题。设计的８０Ｃ１９６为核心的微机控制调速器很好解决了各种控制技术问题。整个系统结构简单。通过改变软件设计,可灵活地实现各种控制功能。试验结果表明这对系统性能有很大提高。     

基于DSP的自诊断步进电机控制系统

本文介绍了一种的新型的步进电机控制系统,采用DSP作为控制器,构建步进电机的驱动系统,并在此基础上实现细分角度和电流的实时运算.利用其片内集成的事件管理模块通过软件实现脉宽调制.提高了系统控制性能,实现步进电机步距角的高精度、连续细分驱动.同时通过振动信号的分析对电机轴承进行故障诊断.综合利用了包络检波和对FFT频谱分析法,有效提高系统的实时性和测量精度,并实现了步进电机在运行中瞬时故障的实时监测和报警.     

高细分步进电机驱动系统

本文采用步进电机双全桥MOSFET驱动芯片THB6128实现对步进电机的高细分驱动.该驱动系统具有速度1~5转固定可调、细分档可调、正反转可调和输出过流保护的功能.     

步进电机细分驱动在喷膜机中的应用

现在已有专用的步进电机细分驱动器，但是对于一些小型产品，采用专用的细分驱动器将会增加成本，这里以四细分驱动在喷膜机中的应用为例，介绍了一种用软件实现步进电机细分驱动的方法，该方法在喷膜机中取得了良好的效果。     

步进电机的微机综合控制

本文以步进电机的细分驱动为中心阐述了步进电机微计算机综合控制的实现。文中以常州微电机厂200BF—001型14.7N·m 的步进电机为例详细地介绍了利用 TP801型单板机实现细分、转向、转速及定位控制的硬件组成和软件设计,并给出了实验结果。文中提出的设计思想及有关硬件和软件稍加修改即可用于其他类型的步进电机控制。     

燃料电池混合动力车能源配置方法研究

燃料电池混合动力车能源系统的配置包括元件尺寸选型、控制策略确定和车辆行驶循环工况选择三要素.文中针对某燃料电池混合动力车的能源系统配置,对能源系统选型、控制策略类型和车辆行驶循环工况三要素分别进行了系统论述.借助于Advisor车辆仿真平台,通过对控制策略采用基线控制的燃料电池混合动力车能源系统配置的实例分析,提出燃料电池混合动力车给出其能源配置的一般方法,最后对仿真结果进行了分析并验证配置方法的有效性和可行性.     

融合类人驾驶行为的无人驾驶深度强化学习方法

现有无人车辆的驾驶策略过于依赖感知-控制映射过程的“正确性”,而忽视了人类驾驶汽车 时所遵循的驾驶逻辑。该研究基于深度确定性策略梯度算法,提出了一种具备类人驾驶行为的端到端 无人驾驶控制策略。通过施加规则约束对智能体连续行为的影响,建立了能够输出符合类人驾驶连续 有序行为的类人驾驶端到端控制网络,对策略输出采用了后验反馈方式,降低了控制策略的危险行为 输出率。针对训练过程中出现的稀疏灾难性事件,提出了一种更符合控制策略优化期望的连续奖励函 数,提高了算法训练的稳定性。不同仿真环境下的实验结果表明,改进后的奖励塑造方式在评价稀疏 灾难性事件时,对目标函数优化期望的近似程度提高了 85.57%,训练效率比传统深度确定性策略梯度 算法提高了 21%,任务成功率提高了 19%,任务执行效率提高了 15.45%,验证了该方法在控制效率和 平顺性方面具备明显优势,显著减少了碰撞事故。     

多机驱动带式输送机功率平衡模糊控制方法

针对以调速型液力偶合器作为驱动装置的带式输送机多机驱动系统采用传统方法控制各驱动电动机之间的功率平衡,存在系统运行过程中动态特性较差、功率平衡调节精度较低等问题,提出一种多机驱动带式输送机功率平衡模糊控制方法:对液力偶合器涡轮转速实行闭环控制,保证在工作机负载发生变化时带式输送机具有恒定不变的带速;转速调节器采用模糊控制器代替传统的PID控制器,以提高功率平衡的调节精度。Matlab仿真结果表明,采用模糊控制方法可有效改善系统动态性能,提高功率平衡调节精度。     

Global stabilisation of a class of generalised cascaded systems by homogeneous method

This paper considers the problem of global stabilisation of a class of generalised cascaded systems. By using the extended adding a power integrator technique, a global controller is first constructed for the driving subsystem. Then based on the homogeneous properties and polynomial assumption, it is shown that the stabilisation of the driving subsystem implies the stabilisation of the overall cascaded system. Meanwhile, by properly choosing some control parameters, the global finite-time stability of the closed-loop cascaded system is also established. The proposed control method has several new features. First, the nonlinear cascaded systems considered in the paper are more general than the conventional ones, since the powers in the nominal part of the driving subsystem are not required to be restricted to ratios of positive odd numbers. Second, the proposed method has some flexible parameters which provide the possibility for designing continuously differentiable controllers for cascaded systems, while the existing designed controllers for such kind of cascaded systems are only continuous. Third, the homogenous and polynomial conditions adopted for the driven subsystem are easier to verify when compared with the matching conditions that are widely used previously. Furthermore, the efficiency of the proposed control method is validated by its application to finite-time tracking control of non-holonomic wheeled mobile robot.     

Measurement of Control Skills,Vigilance, and Performance on a Subsidiary Task during 12 Hours of Car Driving

Eight subjects were given short driving tests at 0700, 1000, 1300, 1400. 1700 and 2000 hours on 2 days: (1) under experimental conditions of continuous driving and (2) under control conditions in which they carried on with their normal work between tests. Car control skills and performance on a subsidiary task of time-interval production were measured on a 2·2 mile test circuit in city traffic. Pulse rate and oral temperature were also recorded. Vigilance was measured during main-road driving on the experimental day by scoring time taken to respond to a light signal. Vigilance improved significantly during the spell of prolonged driving. Time-interval production was reliably more variable under experimental conditions than under control, but this difference was independent of the duration of the driving period. Differences in car-control skills between conditions were slight and statistically unreliable. These results support previous findings that a virtually continuous 12 hour period of driving during the normal working day need not affect either perceptual or motor skills adversely.

The apparent discrepancy between present findings, that performance on the subsidiary task was worse on the day of prolonged driving, and previous findings, that it tended to be better, is briefly discussed in relation to the general problem of measuring performance by the dual-task method.     

Anode‐voltage‐control circuit for compensation of luminance deterioration

Abstract— An external driving circuit that has realized long lifetime, power‐consumption control, and peak luminance for organic light‐emitting diode (OLED) displays have been developed. This circuit realizes an effective method for constant‐anode‐voltage (CV) driving refered to as clamped inverter (CI) driving. The feature of CV driving is to achieve low‐power consumption compared with constant‐anode‐current (CC) driving and to control the power consumption and peak luminance according to the image because display luminance can be easily changed by controlling the anode voltage. On the other hand, CV driving has the problem that luminance deterioration appears to be serious compared with that of CC driving because the current of the OLED element decreases according to usage time. To cope with this, a lifetime compensation circuit that has increased the anode voltage so that it compensates for the luminance deterioration has been developed. This circuit can compensate not only the decrease in current but also the decrease in luminance at a constant current that CC driving cannot. However, increasing the anode voltage causes an increase in stress on the OLED element. The influence of stress on OLED lifetime was verified. As a result, it was confirmed that this circuit can extend the lifetime by 32% even if the anode voltage is increased, causing stress on the OLED structure.     

基于MPC564的发动机电控单元硬件设计

介绍一种基于Freescale公司32位高性能控制芯片MPC564的汽油机电控单元硬件设计方案,包括系统电源模块设计、传感器信号处理电路设计、执行器驱动电路设计等。该电控单元采用高性能的处理芯片、高集成度的信号处理模块和驱动模块,为建立可靠的控制系统、实现复杂的控制算法及扩展控制功能奠定了硬件基础。     

基于二次型性能指标的混合动力汽车实时优化控制

为解决混合动力系统实时优化控制问题,本文提出了一种基于二次型性能指标最优的混合动力汽车功率分配优化方案.通过合理的假设和近似,建立了混合动力系统的线性模型,并利用二次型最优控制理论将混合动力最优控制问题转化为二次型最优调节问题进行求解,得到了一个结构简单的实时优化控制算法.5种道路工况下的仿真结果表明,本文提出的控制方法在未来道路工况未知的情况下能够实现混合动力系统的实时优化控制,且节油率与离线计算以燃油消耗最小为性能指标的全局最优控制的节油率相近.     

可变频变压器的建模仿真与分析

采用高压直流输电方式连接两个异步电网存在谐波干扰、换相失败、难以实现功率平滑调节、无功功率不能随有功功率传输等问题。文章介绍了可变频变压器的的基本结构及原理,研究了可变频变压器的数学模型及控制模型,给出了可变频变压器传输功率与直流驱动电动机提供的驱动转矩之间的数学关系式,在此基础上采用PSCAD软件搭建了可变频变压器模型并进行了仿真研究。仿真结果表明,可变频变压器可以实现两个异步电网之间的连接并进行功率双向平滑传输,响应速度快;通过转速控制器控制直流驱动电动机的转速可使旋转变压器的转速恒定,以弥补两个电网的频差,维持系统平衡。     

Continuous extensions of Rosenbrock-type methods

Solving an initial value problem by a Rosenbrock method produces, in general, the numerical solution at (in advance unknown) gridpoints. Applications requiring frequent output (as graphics, delay differential equations, problems with driving equations) normally restrict the stepsize control of these codes and increase the computational overhead considerably. In this paper we introduce a class of continuous extensions for Rosenbrock-type methods. These extensions furnish a continuous numerical solution without affecting the efficiency of the codes.