基于DSP的直流伺服电机的双闭环控制系统

作为数字阀的电一转换器,电机的频率响应对数字阀的性能有非常直接的影响。为提高数字阀的动态响应,设计了直流伺服电机双闭环系统。该系统采用TMS320LF2812为控制核心,在脉宽调制（PWM）方法的基础上,加入了超前补偿网络提高电流环的带宽;采用PI控制算法实现了电机转子的精确定位。简述了实现该控制系统的硬件设计方案和软件控制策略。实验结果表明,该系统能够实现直流伺服电机的电流和位置控制,显著提高了电流环的频率响应。     

高精度数字电子雕刻机控制系统的研究

从现代数字电子雕刻的基本原理出发,对数字电子雕刻机滚筒传动电机与横向丝杠传动电机之间的关联性控制参数进行了研究,并根据高精度凹版雕刻机的要求,研究了基于磁场定向控制交流伺服电机控制器,在此电机控制器基础上实现了高精度电子雕刻机控制系统.雕刻的结果表明,设计的交流伺服电机控制器及控制系统都能稳定而准确的运行,也表明了研究的关联控制参数是正确的,控制的方法是有效的.     

直流电机的电子稳速与限流控制

直流伺服电机用于位置或转速控制时,通常都接成他激方式,并采用电枢电压控制。直流伺服电机的转矩与电枢电流的关系式为 T=C_TφI-T_o (1) 式(1)表明:电机的转矩近似与电枢电流成正比。直流伺服电机用于转矩加载控制和扭矩测量等场合时,如采用电枢电压控制方式,效果往往不理想。原因是:与电机转矩成比例的是电枢电流,而不是电压;而且一旦出现堵转,容易造成电机电流过载,甚至损坏。本文研究的限流控制方式可以克服上述弊端。     

基于LabWindows/CVI的多路伺服电机控制和在线检测系统

针对多路伺服电机的计算机控制和电机参数在线检测问题,基于LabWindows/CVI虚拟仪器软件平台,结合DSP技术,开发了多路伺服电机控制和在线检测软件系统。该软件系统通过周期性UDP/IP网络组播的方式发送/接收数据报文,能同时实现对多路伺服电机进行控制,并对电机电枢电流、电枢电压、激磁电流、激磁电压及相关性能参数进行在线检测。系统可根据用户需要将在线检测到的数据通过表格、图形实时输出。结果表明该软件系统在实际应用中获得了很好的效果,并具有良好的扩展性。     

基于LabVIEW和MPScope的多轴伺服电机控制系统开发与应用

为了满足多轴伺服电机控制系统研发的需求,缩短开发周期,增强系统的稳定性,提出一种基于Lab VIEW和MPScope的多轴伺服电机控制系统的设计方法。该方法采用工控机+运动控制器+驱动器系统结构,由工控机控制系统运行,通过上位机软件调整控制参数及控制策略,利用MPScope软件实现工控机与运动控制器的通讯,最终实现多轴电机的控制。通过对该系统进行机器人应用测试,各个轴具有很好的控制精度,并能完成机器人的各种动作。应用结果表明,该方法结构简单、性能稳定、控制精度高,适用于各种多轴伺服电机联动控制,具有很高的移植性和扩展性。     

多相电机驱动控制系统的设计与实现

多相电机由于低压大功率、高可靠性和高转矩密度等优点,为电气交通领域提供了一种新的动力解决方案。为此以九相异步电机为例,以DSP主控芯片和IGBT驱动模块为核心,设计了一套多相电机驱动控制系统。基于谐波电流闭环的转子磁场定向矢量控制方法,对多相电机驱动控制系统进行了性能测试。实验结果表明,该驱动控制系统能够准确控制多相电机的电流和转速,充分发挥多相电机的高转矩密度优势,驱动控制系统的设计合理且有效。     

交流伺服电机传动参数检测方法在故障检测中的应用

论文给出了一种间接检测交流伺服电机传动参数的方法,按照这一方法,只需检测交流伺服电机的定子电流,即可通过计算得到电机的转矩、转速和转角。该方法可用于伺服传动链的故障检测。     

基于Simulink的IPMSM矢量控制策略研究

在分析内埋式永磁同步电机(IPMSM)数学模型的基础上,利用Simulink建立了IPMSM矢量控制系统仿真模型,分别建立了速度控制模块、电流滞环控制模块、坐标转换模块等子模块,并对IPMSM矢量控制系统弱磁控制进行了仿真研究。仿真结果证明了该方法的快速性和有效性,为实际电机控制系统的分析、设计和调试提供了新的思路。     

基于PLC的台式钻床的自动化控制系统研究

为满足机床加工需求和提高加工效率,将传统台式钻床加工方式进行改造,设计了一种基于PLC自动化控制的钻床加工系统。以PLC作为控制器,换向电磁阀、伺服电机、液压缸为驱动设备的控制方法,重点讲解了液压回路、控制系统的硬件组成、电控原理以及PID参数对控制电机影响。最后,成功连接整个控制系统回路,并进行钻床调试和实验。实验数据表明:该钻床自动化加工控制系统设计合理,能够达到实际加工要求。     

基于DSP的交流数字伺服控制系统

论述了一种基于DSP的交流伺服电机数字控制系统实现方案.该系统以SVPWM矢量控制技术为基础,以TI公司的TMS320F2812 DSP为核心,实现交流伺服.电机复杂的矢量控制,能够对电机进行平稳调速与实时控制,并显著缩短电机稳定时间.给出了系统的硬件和软件算法方案.     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.