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电子信息工程外文翻译外文文献英文文献文献翻译

电子信息工程外文翻译外文文献英文文献文献翻译
电子信息工程外文翻译外文文献英文文献文献翻译

Technology and Application of Fieldbus Control System -------- Intelligent

Equipment & Measurement And Control System Based on DeviceNet

Promoted by the new technological revolution that automation control technology is tending digitization and internet in the field of automation industry, Shanghai Aton Electric Co., Ltd. developed Intelligent Equipment & Measurement And Control System Based on DeviceNet as a high and new technology industrialization model project. It was a state hi-tech development project of 2000 and was approved by the State Committee of Technology. Shanghai Aton Electric Co., Ltd. constructed production line of intelligent controller of pump and valve, relying on Shanghai Electric (Group) Corporation; constructed measurement and control system FCS R&D center of intelligent controller of pump and valve and built up mass production R&D basis, cooperating with Shanghai Jiaotong University and Shanghai University; constructed FCS remote diagnosis and service center of intelligent controller of pump and valve; constructed FCS training center of intelligent controller of pump and valve; founded mass production R&D basis along with the Rockwell Laboratory of Shanghai Jiaotong University and CIMS Center.

1 Summary

(1)Fieldbus control system is a system applied to field of production and microcomputerized measurement control equipment to realize both-way multinode serial communications. It is also called low-level control network for open, digital and multiplespot communications.

Application: Flow Control System of Manufacturing; Process Control System; Traffic Control & Management; Building Automation. Features: Fieldbus control system is low-level low-bandwidth digital communication and control network in industrial system as well as open system connecting microcomputerized appearance. Intelligent instrument and controller are equal to microcomputer. They make up network with Fieldbus control system as the links to complete digital communication and other tasks.

(2)Difference between FCS and DCS,FCS is updated control system after DCS integrated with digital control system and distributing control system. It solves the problem that in traditional DCS, devices made by different manufacturers cannot be connected. They can't realize exchange and operation to organize an network system with wider range of information sharing. It conquers the defect that special closed system for network should be used for communication in DCS to realize various functions of integrated automation. It turns the distributing structure combining concentration with deconcentration in DCS into new-type full distributing structure. It

releases the control function to the field thoroughly and makes it possible to realize basic control function by means of fieldbus equipment itself. FCS breaks the traditional structure form of control system. The traditional analog control system adopts one-to-one equipment tie-wire and puts up connections respectively according to control loop. FCS adopts intelligent field equipment to place the control module, all input/output modules that used to be in the control chamber of DCS into field equipment. Since field equipment has ability to communicate, the field measuring and transferring instruments can transfer signals to actuating mechanism such as valve directly. Its control function can be fulfilled directly on the spot independent of the computer or control meter in the control chamber, which realizes thorough decentralized control.

FCS adopts digital signals to replace analog signals so that multiple signals (including multiple operating parameter values, device status and failure information) can be transferred on a pair of cables. Meanwhile, it can give power supply to several devices. No switched block for analog/digital or digital/analog is needed besides fieldbus.

(3) C haracteristics of FCS

? Open System;

? Interoperability;

? replace ability of devices made by different manufacturers.

? Intelligentize and Autonomy;

? Field equipment completing basic functions of automatic control.

? Decentralized System Structure;

? Field Adaptability;

? Relatively Strong Interference Killing Feature and Safety

? Intelligentized local equipment can save investment and quantity of hardware

? Saving installation expenses and cables

? Saving daily maintenance expenses

? Enhancing accuracy and reliability of system

? Enhancing initiativeness of system integration for users

(4) Development Background and Trend of Fieldbus Control System, With the rapid development of computer and computer network, FCS has been rapidly developed as the interlinked communication network between the field intelligent

devices in the field of process automation, building and traffic etc. Because FCS meets the needs that industrial control system is developing in the way of decentralization, network and intellectualized, it has become the focus of global industrial automation and been universally concerned by the whole world. FCS has causedgreat revolutions on the aspects of system structure and function system for the current production of automation instrument, distributing control system and programmable controller. It is predicted that FCS will be the general trends in a very long time in the future fore sure.

2 APPLICATION OF RELAY

The product reliability generally refers to the operating reliability. It is defined as: the ability of accomplishing the specified function under prescribed conditions and in prescribed time. It consists of intrinsic reliability and application reliability. The intrinsic reliability is determined by product designing and manufacturing technique, and the application reliability is concerned with the correct application of users and the services provided by the manufacturer before and after selling. When using relay, the user should pay attention to the following items.

2.1 Coil applied voltage

It is best to choose the coil applicative voltage according to the rated voltage in design, or choose the voltage according to the temperature rising curve. Using any coil voltage that is less than the rated voltage will affect the operation of the relay. The coil operating voltage refers to the voltage that is applied between the coil terminals. The voltage value between the two terminals must be guaranteed, especially when using enlargement circuit to energize the coil. Whereas, it will also affect the relay characteristics if the applied voltage exceeds the highest rated voltage. Exorbitant voltage will bring exorbitant coil temperaturerising, especially in high temperature ambient. Exorbitant temperature rising will damage the insulating material and affect the working safety of relay. For magnetic latching relay, energizing (or return) pulse width should not less than 3 times of the operating (or return) time, otherwise, the relay would be left on the middle-position state. When using solid-state components to energize the coil, the components dielectric strength must be above 80V, and the leakage of current must be as little as possible to ensure the relay to release.

Energizing power source: Under 110% of the rated current, the adjusting ratio of the power source is less than 10% (or the output impedance is less than 5% of the coil impedance), the wave voltage of the DC power source is less than 5%. The AC wave is sine wave; the waviness coefficient is between 0.95~1.25; wave distortion is within ±10%; the frequency change is within ±1Hz or ±1% of the specified frequency (choosing the bigger value). The output power should not less than coil power consumption.

2.2 Transient suppression

At the moment when the coil power is stopped, peak-inverse voltage that is more than 30 times of

the coil rated voltage is produced on the coil, which is harmful to the electronic circuit. Generally, the peak-inverse voltage is suppressedby transient suppression (cutting-peak) diode or resistance to limit the peak-inverse voltage within 50V. But the diode in parallel connection will delay3~5 times of the release time. If the request of the release time is high, a suitable resistance in series can be putted with and at one end of the diode.The power supply to relays in parallel connection and series connection, When several relays in parallel connection are supplied, the relay that the peak-inverse voltage is higher will release power to the relays that the peak-inverse voltage is lower. The release time of the relay will delay. So the relays in parallel connection should be controlled separately to eliminate mutual influence.

The relays with different coil resistance and power can'bt e used in series, otherwise, the relay that the coil current is higher in the series circuit can'otperate reliably. Only the relays of the same specification can be used in series, but the peak-inverse voltage will be increased and the peak-inverse voltage should be suppressed. Resistance in series can be used to bear the part voltage that exceeds the rated voltage of the coil according to the ratio of the divided voltage.

2.2.1 Contact load

The load applied to the contacts should be accordant to the rated load and characteristics of the contacts. A load that is not applied according to the rated value range will cause problem. The relay that is only suitable for DC load can used in ' t be AC occasions. The relay that can switch 10A load can ' t always reliably operate in low level load (less tha n 10m AX6A) or in dry circuit occasi ons. The relay that can switch single-phase AC power source isn 'atlways suitable to switch two single-phase AC loads that aren 't synchronous; the relay that is onlyiesdpteocisfwitch the load of AC 50Hz(or 60Hz)can't be used to switch AC load of 400Hz.

2.2.2 Parallel and series connection of contacts

The contacts used in parallel connection can ' t increase the load current, because

the operating times of several sets of contacts are absolutely different; that is to say, there is still only a set of contacts switching the increased load. This would damage or weld the contacts and make the contacts can ' t close or open. The parallel connection

of the contacts can decreasehte misplay of “ break ” . But the parallel connection of the contacts would increase the misplay of “ freezing ”. Because the misplay of “bre the main pattern of invalidation of contacts, the parallel connection can increase the reliability and can be used on the pivotal part of equipments. But the applied voltage should not exceed the highest operating voltage of the coil and should not less than 90% of the rated voltage, otherwise, the coil life and the applicative reliability would be damaged. The series connection of the contacts can increase

the load voltage. The amount of the contact sets is equal to the times that the load voltage can be increased.

The series connection of contacts can decrease the misplay of “ freezing ”, but it w increase the misplay of “ break ”An. yway, when using redundant technology to increase the operating reliability of contacts, the characteristics and size and the failure mode of load must be considered.

2.2.3 Switching speed

The switching speed should not exceed the reciprocal of 10 times of the sum of operating and release time (times/s), otherwise, the contacts can ' t switch on stead Magnetic latching should be used under the pulse width specified in the technique criterion, or the coil may be damaged.

3 RVT DISTRIBUTING ELECTRICITY INTEGRATE TEST APPARATUS

Basic function

Measure asupervision:Three mutually electric voltage/electric current/ power factor with a great achievement/ power without a great achievement/electricity with a great

achiverment/electricity/homophonic-wave electric voltage/ homophonic-wave electric/ current Day electric voltage/ electric current biggest and minimum value/fire for the failure Electric voltage over top, the limit/ lack mutually of time homophonic-wave analyzes is up to 13 times.The data is stored for 2 months. The data communicate

RS232/485 communicating connect,The way in communicating can adopt the spot communicating or the long range communicating. ,Possible to settle invoke or

the solid hour invokes, responding to the modification and long ranges control of the parameter. Without power compensation

Taking physics measuresas the power factor without a great achievement,the power factor with a great achievement and the dull place without power compensation;Y+ the combination method of the △,Y+ the △ connects the line method,Y+ △ , Y, the △ connects the line method. Data management

According to WINDOW98 operation terrace, data in communication automatically reports born statement, curve and pillar form diagrams. Circulation of the protection

When the charged barbed wire net of mutually electric voltage over press, owe to press, and a super limit hour fast cut off in expiation of capacitor,When the charged barbed wire net lacks mutually or super limit in the preface of zero hour fast cut off in expiation of capacitor. screen manifestation

Chinese operation interface ,Adopt 128*64 the back light liquid crystal display.The solid hour shows the charged barbed wire net relevant parameter.view manifestation to place the parameter.

现场总线控制系统的技术和应用

随着新的科学技术革命的出现,在自动化工业领域中,自动控制技术的发展趋向于数字化和网络互联化。上海Aton 电气有限公司在基于DeviceNet 网络协议研制了智能设备、智能测量法和只能控制系统,建立了工业化高新技术工程模型。这是2000 年国家重点发展的高科技项目,并且由国家科技委员会认可。通过上海电气集团,上海Aton 电气有限公司构造了汞和阀门的智能控制器的的生产线;创立了汞和阀门的智能控制器的现场控制系统的研发中心,通过和上海交通大学和上海大学的合作,建立了产品集成的研发基础;建立了汞和阀门的智能控制器的现场控制系统的远程诊断和服务中心;建立了汞和阀门智能控制系统的现场控制系统的培训中心;通过和上海交通大学洛氏实验室和计算机集成制造系统中心的合作,建立了集成产品研发的基础。

1 概要

(1) 现场总线控制系统就是应用于制造业中和应用微机和测量控制设备来实现多点双工的连续通信的系统。它也被称为是开放式、数字化和多点通信的低级控制网络。

应用:制造业中流程控制系统

过程控制系统交通的控制和管理智能大厦特征:现场总线控制系统应用于工业系

统中的一中低级、低带宽的数字式化通信和控制的网络,同时它一种连接微机的

开放式系统。智能仪表和控制器就相当于微型计算机。智能仪表和控制器组成现

场总线控制系统作为一种链接来实现数字通信和其他的功能。

(2) 现场总线和集散控制系统的差别

现场总线控制系统是综合集散控制系统、数字控制系统和分布式控制系统发展起来的系统。现场总线控制系统解决了集散控制系统中不同厂商生产的设备不能连接的传统毛病。在集散控制系统中,各设备之间不能实现相互间的数据交换和操作,以致不能组成一个网络实现远程的信息共享。现场总线控制系统克服了在集散控制系统通信中,为实现自动控制的各种功能时必须用到专用的封闭式系

统来组建网络的缺点。现场总线控制系统改变了集散控制系统中将各分散系统组合在一块的结构,

取而代之的是一中新型的完整的分布式结构。它完全解放了现场控制的功能,同时使通过现场总线设备来实现智能控制成为可能。现场总线控制系统突破了传统的控制系统的结构方式。在传统的控制系统中都是采用一对一的接线方式(即各个仪表之间是没有相互联系的) ,然后在根据控制回路来分别的连接这些设备的接线。现场总线控制系统采用智能的现场设备来作为控制模块,所有曾经用于集散控制系统中的输入/ 输出模块都用现场仪表代替。因为现场设备能实现通信功能,所以现场测量仪和传送仪可以将现场采集到的数据来直接控制比如阀门等这些机械装置。我们既可以通过现场的计算机来单独实现系统的控制功能,也可以通过控制在控制室的仪表来单独实现系统的控制功能,从而实现彻底的分散式控制。

现场总线控制系统采用数字信号代替模拟信号,从而实现在一条电缆上传输更多的信号(包括真

红外数据通信技术外文翻译文献

红外数据通信技术外文翻译文献(文档含中英文对照即英文原文和中文翻译) Infrared Remote Control System Abstract Red outside data correspondence the technique be currently within the scope of world drive extensive usage of a kind of wireless conjunction technique, drive numerous hardware and software platform support. Red outside the transceiver product have cost low, small scaled turn, the baud rate be quick, point to point SSL, be free from electromagnetism thousand Raos

etc. characteristics, can realization information at dissimilarity of the product fast, convenience, safely exchange and transmission, at short distance wireless deliver aspect to own very obvious of advantage. Along with red outside the data deliver a technique more and more mature, the cost descend, red outside the transceiver necessarily will get at the short distance communication realm more extensive of application. The purpose that design this system is transmit customer’s operation information with infrared rays for transmit media, then demodulate original signal with receive circuit. It use coding chip to modulate signal and use decoding chip to demodulate signal. The coding chip is PT2262 and decoding chip is PT2272. Both chips are made in Taiwan. Main work principle is that we provide to input the information for the PT2262 with coding keyboard. The input information was coded by PT2262 and loading to high frequent load wave whose frequent is 38 kHz, then modulate infrared transmit dioxide and radiate space outside when it attian enough power. The receive circuit receive the signal and demodulate original information. The original signal was decoded by PT2272, so as to drive some circuit to accomplish customer’s operation demand. Keywords: Infrared dray;Code;Decoding;LM386;Red outside transceiver 1 Introduction 1.1 research the background and significance Infrared Data Communication Technology is the world wide use of a wireless connection technology, by the many hardware and software platforms supported. Is a data through electrical pulses and infrared optical pulse switch between the wireless data transceiver technology.

土木工程类专业英文文献及翻译

PA VEMENT PROBLEMS CAUSED BY COLLAPSIBLE SUBGRADES By Sandra L. Houston,1 Associate Member, ASCE (Reviewed by the Highway Division) ABSTRACT: Problem subgrade materials consisting of collapsible soils are com- mon in arid environments, which have climatic conditions and depositional and weathering processes favorable to their formation. Included herein is a discussion of predictive techniques that use commonly available laboratory equipment and testing methods for obtaining reliable estimates of the volume change for these problem soils. A method for predicting relevant stresses and corresponding collapse strains for typical pavement subgrades is presented. Relatively simple methods of evaluating potential volume change, based on results of familiar laboratory tests, are used. INTRODUCTION When a soil is given free access to water, it may decrease in volume, increase in volume, or do nothing. A soil that increases in volume is called a swelling or expansive soil, and a soil that decreases in volume is called a collapsible soil. The amount of volume change that occurs depends on the soil type and structure, the initial soil density, the imposed stress state, and the degree and extent of wetting. Subgrade materials comprised of soils that change volume upon wetting have caused distress to highways since the be- ginning of the professional practice and have cost many millions of dollars in roadway repairs. The prediction of the volume changes that may occur in the field is the first step in making an economic decision for dealing with these problem subgrade materials. Each project will have different design considerations, economic con- straints, and risk factors that will have to be taken into account. However, with a reliable method for making volume change predictions, the best design relative to the subgrade soils becomes a matter of economic comparison, and a much more rational design approach may be made. For example, typical techniques for dealing with expansive clays include: (1) In situ treatments with substances such as lime, cement, or fly-ash; (2) seepage barriers and/ or drainage systems; or (3) a computing of the serviceability loss and a mod- ification of the design to "accept" the anticipated expansion. In order to make the most economical decision, the amount of volume change (especially non- uniform volume change) must be accurately estimated, and the degree of road roughness evaluated from these data. Similarly, alternative design techniques are available for any roadway problem. The emphasis here will be placed on presenting economical and simple methods for: (1) Determining whether the subgrade materials are collapsible; and (2) estimating the amount of volume change that is likely to occur in the 'Asst. Prof., Ctr. for Advanced Res. in Transp., Arizona State Univ., Tempe, AZ 85287. Note. Discussion open until April 1, 1989. To extend the closing date one month,

英文文献翻译

中等分辨率制备分离的 快速色谱技术 W. Clark Still,* Michael K a h n , and Abhijit Mitra Departm(7nt o/ Chemistry, Columbia Uniuersity,1Veu York, Neu; York 10027 ReceiLied January 26, 1978 我们希望找到一种简单的吸附色谱技术用于有机化合物的常规净化。这种技术是适于传统的有机物大规模制备分离,该技术需使用长柱色谱法。尽管这种技术得到的效果非常好,但是其需要消耗大量的时间,并且由于频带拖尾经常出现低复原率。当分离的样本剂量大于1或者2g时,这些问题显得更加突出。近年来,几种制备系统已经进行了改进,能将分离时间减少到1-3h,并允许各成分的分辨率ΔR f≥(使用薄层色谱分析进行分析)。在这些方法中,在我们的实验室中,媒介压力色谱法1和短柱色谱法2是最成功的。最近,我们发现一种可以将分离速度大幅度提升的技术,可用于反应产物的常规提纯,我们将这种技术称为急骤色谱法。虽然这种技术的分辨率只是中等(ΔR f≥),而且构建这个系统花费非常低,并且能在10-15min内分离重量在的样本。4 急骤色谱法是以空气压力驱动的混合介质压力以及短柱色谱法为基础,专门针对快速分离,介质压力以及短柱色谱已经进行了优化。优化实验是在一组标准条件5下进行的,优化实验使用苯甲醇作为样本,放在一个20mm*5in.的硅胶柱60内,使用Tracor 970紫外检测器监测圆柱的输出。分辨率通过持续时间(r)和峰宽(w,w/2)的比率进行测定的(Figure 1),结果如图2-4所示,图2-4分别放映分辨率随着硅胶颗粒大小、洗脱液流速和样本大小的变化。

电子信息工程专业课程翻译中英文对照表

电子信息工程专业课程名称中英文翻译对照 (2009级培养计划)

实践环节翻译

高等数学Advanced Mathematics 大学物理College Physics 线性代数Linear Algebra 复变函数与积分变换Functions of Complex Variable and Integral Transforms 概率论与随机过程Probability and Random Process 物理实验Experiments of College Physics 数理方程Equations of Mathematical Physics 电子信息工程概论Introduction to Electronic and Information Engineering 计算机应用基础Fundamentals of Computer Application 电路原理Principles of Circuit 模拟电子技术基础Fundamentals of Analog Electronics 数字电子技术基础Fundamentals of Digital Electronics C语言程序设计The C Programming Language 信息论基础Fundamentals of Information Theory 信号与线性系统Signals and Linear Systems 微机原理与接口技术Microcomputer Principles and Interface Technology 马克思主义基本原理Fundamentals of Marxism 毛泽东思想、邓小平理论 和“三个代表”重要思想 概论 Thoughts of Mao and Deng 中国近现代史纲要Modern Chinese History 思想道德修养与法律基 础 Moral Education & Law Basis 形势与政策Situation and Policy 英语College English 体育Physical Education 当代世界经济与政治Modern Global Economy and Politics 卫生健康教育Health Education 心理健康知识讲座Psychological Health Knowledge Lecture 公共艺术课程Public Arts 文献检索Literature Retrieval 军事理论Military Theory 普通话语音常识及训练Mandarin Knowledge and Training 大学生职业生涯策划 (就业指导) Career Planning (Guidance of Employment ) 专题学术讲座Optional Course Lecture 科技文献写作Sci-tech Document Writing 高频电子线路High-Frequency Electronic Circuits 通信原理Communications Theory 数字信号处理Digital Signal Processing 计算机网络Computer Networks 电磁场与微波技术Electromagnetic Field and Microwave

土木工程外文翻译

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