电子信息工程-外文翻译-外文文献-英文文献-文献翻译.doc

Technology and Application of Fieldbus Control System -Intelligent Equipment & Measurement And Control System Based on DeviceNetPromoted 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 cant 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)Characteristics 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 caused great 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 RELAYThe 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 temperature rising, 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 0.951.25; 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 suppressed by transient suppression （cutting-peak） diode or resistance to limit the peak-inverse voltage within 50V. But the diode in parallel connection will delay35 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 cant be used in series, otherwise, the relay that the coil current is higher in the series circuit cant operate 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 cant be used in AC occasions. The relay that can switch 10A load cant always reliably operate in low level load (less than 10mA6A) or in dry circuit occasions. The relay that can switch single-phase AC power source isnt always suitable to switch two single-phase AC loads that arent synchronous; the relay that is only specified to switch the load of AC 50Hz（or 60Hz）cant be used to switch AC load of 400Hz.2.2.2 Parallel and series connection of contacts The contacts used in parallel connection cant 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 cant close or open. The parallel connection of the contacts can decrease the misplay of “break”. But the parallel connection of the contacts would increase the misplay of “freezing”. Because the misplay of “break” is 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 would increase the misplay of “break”. Anyway, 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 cant switch on steadily. 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 APPARATUSBasic 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 measures as 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 manifestationChinese 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（包括真正工作的参数值、设备的运行情况和失败的信息）。同时，它可以同时给若干个设备供电。另外，除了现场总线外，系统中不在需要模/数或者数/模的转换卡。(3)现场总线控制系统的特性开放式系统 互用性 不同厂商生产的设备可以互相替用 智能化 现场仪表可以实现自动控制的基本功能 分散式系统结构 现场适应性 强大的抗冲突性和安全性 所需附加设备少 安装费用和所用电缆少 节省了每天的维护费用 提高了系统的精确性和可靠性 (4)现场总线控制系统的发展背景和发展前景随着计算机和计算机网络的高速发展，现场总线控制系统作为连接应用于过程自动化领域、智能大厦和交通系统中的智能设备间的通信网络，也已