PLC控制系统故障检测方法与应用

结合研究ＰＬＣ系统的实例,提出并讨论了ＰＬＣ控制系统故障检测的多种方法,可适用于ＰＬＣ系统故障检测。     

PLC在潜水泵电性能检测系统中应用

针对潜水泵电性能检测系统,介绍其整体的硬件结构、原理以及关键技术,阐述ＰＬＣ在该系统中的作用和ＰＬＣ的软件结构。     

PLC在潜水泵电性能检测系统中的应用

针对潜水泵电性能检测系统，介绍其整体的硬件结构，原理以及关键技术，阐述了ＰＬＣ在该系统的中的作用和ＰＬＣ的软件结构。     

PLC在外圆磨床在线检测自动控制中的应用

介绍了外圆磨削在线检测自动控制过程中,ＰＬＣ的控制功能以及ＰＬＣ与数控系统中Ｉ／Ｏ接口的连接及应用,并介绍了该数控系统的判别ＰＬＣ信号的方法。     

PLC在机电设备故障诊断中的应用研究

分析ＰＬＣ对机电设备故障的诊断原理和它在故障诊断系统中的作用,利用ＰＬＣ和计算机构成的诊断系统实现了故障诊断的智能化。充分利用机电设备控制系统中ＰＬＣ的硬件资源,可简化诊断系统的硬件设计。     

PLC与IPC在机电系统中的应用

本文探讨了ＰＬＣ与ＩＰＣ之间的关系,讨论了ＰＬＣ与ＩＰＣ的特点及其在机电系统中的分工协作,重点论述ＰＬＣ与ＩＰＣ之间的通信。     

IPC+PLC+MCC电站锅炉吹灰监控系统

描述了ＩＰＣ＋ＰＬＣ＋ＭＣＣ在火电锅炉吹灰监控系统中的应用。系统取消了以往锅炉模拟屏和按钮群，而由大屏幕彩色显示器动态监视吹灰工艺全过程，由软操作（薄膜密封或寻标）来控制、管理整个吹灰系统。系统解决了由于ＰＬＣ内存不够的缺点，将大量数据存放于硬盘中，而不是ＰＬＣ存储器中，本系统有１４套可任意排列组合的吹灰逻辑，每套逻辑有２５６个可任意排列组合的设备代码，运行人员可以组态１２８４５０５６种吹灰工艺，     

触摸屏与可编程控制器在制冷行业中的应用

本文介绍ＣＱＭＩ和ＰＬＣ与ＮＴ３０Ｃ触摸屏在制冷机组电气控制系统改造上的应用，包括系统中ＰＬＣ与触摸屏软硬件的设计。     

用中文Word97绘制PLC梯形图

随着自动化水平的不断提高，可编程控制器的应用越来越普遍，需绘制ＰＬＣ梯形图越来越多。绘制ＰＬＣ梯形图要做大量重复性的工作，并且一旦要修改，则需重新绘制。设计速度慢、工作效率低。计算机的广泛应用，Ｗｏｒｄ９７亦越来越为人民熟知。利用 Ｗｒｒｄ９７的强大功能不仅可以处理各种文档，而且能够利用 Ｗｏｒｄ ９７的图形处理功能绘制 ＰＬＣ梯形图，具体做法如下。１ 建立ＰＬＣ元器件符号库 首先打开 Ｗｏｒｄ９７选择“文件＼新建──空文档”。然后选择工具栏中“绘图”选项，根据不同型号ＰＬＣ的规则，将所创建的各元器件…     

PLC控制系统常见的故障自动检测法

ＰＬＣ控制系统常见的故障自动检测法吕景泉天津中德培训中心天津：３００１９１ＰＬＣ控制系统中，需要检测和控制的设备很多，各种设备或元件在生产过程中都可能产生故障或误动作，给生产造成损失，因此，故障的自动检测对及时发现和处理故障是十分必要的。在ＰＬＣ构成...     

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...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

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.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

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.     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.