開題報(bào)告模板3.doc

一本課題的研究意義、研究現(xiàn)狀和發(fā)展現(xiàn)狀1. 本課題的研究意義 鍋爐是工業(yè)火力發(fā)電廠企業(yè)的重要?jiǎng)恿υO(shè)備，它是火力發(fā)電廠三大主機(jī)之一，鍋爐工業(yè)的發(fā)展影響著火力發(fā)電的發(fā)展和大電站的建設(shè)，此外，鍋爐還是輕工業(yè)生產(chǎn)中的熱源和動(dòng)力源，如為蒸餾、化學(xué)反應(yīng)、干燥蒸發(fā)等提供熱能，為風(fēng)機(jī)、壓縮機(jī)、泵類提供動(dòng)力。由此可見國民經(jīng)濟(jì)各個(gè)部門的發(fā)展離不開鍋爐工業(yè)的發(fā)展，它在我們建設(shè)有中國特色社會(huì)主義，大力發(fā)展經(jīng)濟(jì)，實(shí)現(xiàn)現(xiàn)代化的進(jìn)程中，發(fā)揮著重要作用。 氣包水位是鍋爐系統(tǒng)正常運(yùn)行的重要參數(shù)，維護(hù)鍋爐水位在一定范圍內(nèi)變化，是鍋爐水位控制的重要任務(wù)之一，也是保障蒸汽機(jī)和鍋爐安全運(yùn)行的重要條件。如果氣泡水位過高，會(huì)影響汽包的汽水分離裝置的正常工作，導(dǎo)致鍋爐出口蒸汽帶水和含鹽量過大，使過熱器熱面結(jié)垢甚至遭到破壞，影響機(jī)組的正常運(yùn)行和經(jīng)濟(jì)性指標(biāo)；如果汽包水位過低，會(huì)使鍋爐水循環(huán)工況破壞，造成水冷壁供水不足而被燒壞，所以研究鍋爐汽包水位的控制方法有著重要意義。 2. 研究現(xiàn)狀和發(fā)展趨勢(shì) 我國工業(yè)鍋爐的自動(dòng)化控制，經(jīng)歷了三四十年代的單參數(shù)控制，四五十年代的單元組合式綜合參數(shù)儀表控制從六十年代開始，人們對(duì)鍋爐水位系統(tǒng)進(jìn)行了更深入的研究，采用更先進(jìn)的計(jì)算機(jī)控制方法，如數(shù)字PID控制、最優(yōu)控制、自適應(yīng)控制等。在控制結(jié)構(gòu)上采用串級(jí) -前饋-反饋控制。針對(duì)控制鍋爐對(duì)象的滯后特性，采用Smith純滯后補(bǔ)償控制等。比如：文獻(xiàn)針對(duì)當(dāng)時(shí)鍋爐水位控制中大多數(shù)采用的DDZ-II型電動(dòng)單元組合儀表電路，故障率高，調(diào)節(jié)效果差等特點(diǎn)，設(shè)計(jì)并制作出一種采用PID調(diào)節(jié)原理的新型智能水位控制儀。 鍋爐工業(yè)的迅猛發(fā)展是近幾年的事情，國外的鍋爐工業(yè)50年代發(fā)展最快，70年代達(dá)到高峰。一直以來，用單片機(jī)實(shí)現(xiàn)鍋爐控制是控制領(lǐng)域的一個(gè)典型的問題，伴隨著控制理論和技術(shù)的發(fā)展，鍋爐自動(dòng)化控制水平也在逐漸提高，鍋爐的自動(dòng)化控制，經(jīng)歷了30年代的單參數(shù)控制，40年代的組合儀表復(fù)合參數(shù)儀表控制，以及60年代興起的計(jì)算機(jī)過程控制幾個(gè)階段。而用單片機(jī)實(shí)現(xiàn)鍋爐的控制，也是近幾年才發(fā)展起來的，是一個(gè)逐漸深入的過程，雖然與其他發(fā)達(dá)國家相比還存在差距，但是在此方面的進(jìn)步卻是很大的。 國外許多學(xué)者正深入地研究汽包水位智能控制方法。1974年英國的E.H.Mamdani ，成功的將模糊控制應(yīng)用到鍋爐和蒸汽機(jī)控制中，此后，模糊控制得到了廣泛的發(fā)展并在現(xiàn)實(shí)中得到了成功的應(yīng)用。國內(nèi)的許多學(xué)者對(duì)汽包水位模糊控制也進(jìn)行了深入的研究，如哈爾濱工程大學(xué)的夏國清等針對(duì)鍋爐水位問題，提出了一種自學(xué)習(xí)模糊控制方法，并進(jìn)行仿真研究，驗(yàn)證了模糊控制對(duì)汽包水位模型參數(shù)變化不敏感，抗干擾能力強(qiáng)等優(yōu)點(diǎn)，解決了對(duì)象數(shù)學(xué)模型不精確時(shí)控制器的適應(yīng)性問題。 但是，常規(guī)的二維PID模糊控制存在比較大的靜態(tài)誤差和多級(jí)繼電器特性，降低了它的精度,所以有必要對(duì)模糊控制進(jìn)入更深入的研究，以便提高對(duì)汽包水位系統(tǒng)控制的性能。近年來，集散控制系統(tǒng)系統(tǒng)（DCS）迅速發(fā)展并為鍋爐控制提供了強(qiáng)有力的手段，特別是在集散控制系統(tǒng)中采用模糊控制等高級(jí)算法已經(jīng)成為集散控制系統(tǒng)發(fā)展的一個(gè)重要組成部分?？偟膩碚f，汽包水位控制到經(jīng)歷了一個(gè)由單元組合式儀表到計(jì)算機(jī)控制，由傳統(tǒng)的PID控制到更高級(jí)的智能控制，由直接現(xiàn)場(chǎng)到集散控制的發(fā)展過程。二主要設(shè)計(jì)內(nèi)容采用三沖量水位控制系統(tǒng)，以鍋爐水位為主控信號(hào)，蒸汽流量為前饋信號(hào)，給水流量為控制器的反饋信號(hào)；采用以單片機(jī)為核心的硬件電路，實(shí)現(xiàn)鍋爐水位的智能控制系統(tǒng)。3 研究方案： 三沖量控制系統(tǒng)從結(jié)構(gòu)上來說，是一個(gè)帶有前饋信號(hào)的串級(jí)控制系統(tǒng)。液位控制器LC（主調(diào)節(jié)器）與流量控制器FC（副調(diào)節(jié)器）構(gòu)成串級(jí)控制系統(tǒng)。蒸汽流量的波動(dòng)是引起汽包液位變化的因素，是干擾作用;要實(shí)現(xiàn)蒸汽流量擾動(dòng)下水位不變的設(shè)想，三沖量水位控制系統(tǒng)以蒸汽流量為前饋信號(hào)，給水流量為控制的反饋信號(hào)，鍋爐水位是主沖量信號(hào)，首先用變送器從鍋爐汽包中采集到的這些物理參數(shù)轉(zhuǎn)化為模擬信號(hào)，然后通過A/D轉(zhuǎn)換器轉(zhuǎn)換成單片機(jī)可識(shí)別的數(shù)字信號(hào)，將其送入單片機(jī)中進(jìn)行處理，隨后將輸出信號(hào)再通過D/A轉(zhuǎn)換器轉(zhuǎn)換為模擬信號(hào)，最后將處理后的信號(hào)送入執(zhí)行器，執(zhí)行器通過控制給水流量來完成對(duì)鍋爐汽包水位的調(diào)節(jié)工作。同時(shí)把水位進(jìn)行顯示，超標(biāo)時(shí)進(jìn)行報(bào)警處理，同時(shí)具有人機(jī)交互功能，和顯示功能。 鍋爐液位檢測(cè)變送器給水流量變送器蒸汽流量變送器 執(zhí)行器 A/D D/A 人-機(jī)交互 顯示 報(bào)警 通信 單 片 機(jī) 設(shè)計(jì)方案框圖位變送液器重點(diǎn)：設(shè)計(jì)一個(gè)以單片機(jī)8051為核心的智能鍋爐水位控制系統(tǒng)難點(diǎn)：如何用軟件實(shí)現(xiàn)模糊前饋控制和PID控制途徑：1，進(jìn)入網(wǎng)上圖書館查閱相關(guān)質(zhì)料 2，從書店借閱相關(guān)書籍 3:，充分利用使用實(shí)驗(yàn)室里的控制系統(tǒng)設(shè)備分析了解 工作計(jì)劃1-4周 搜集資料，熟悉課題，明確設(shè)計(jì)目的和要求， 確定設(shè)計(jì)整體框架，準(zhǔn)備開題報(bào)告 5 周 確定設(shè)計(jì)方案 儀表選型6-7 周 做好硬件設(shè)計(jì)8-9 周 做好軟件設(shè)計(jì)10-12 周 軟件，硬件調(diào)試，修改13-15 周 撰寫畢業(yè)設(shè)計(jì)16-17 周 畢業(yè)答辯參考文獻(xiàn) 1陳振山，高明帥，張紅俠，火電廠鍋爐汽包水位的智能控制研究J，科技信息.p02012,3；【2】董海運(yùn)，肖航 船用鍋爐汽包水位模糊控制研究J.中國艦船研究 2009,01；【3】高雪峰 淺談?wù)羝仩t水位自動(dòng)控制J.科技信息 2009,04【4】彭雪峰，張怡典 智能鍋爐水位控制系統(tǒng)設(shè)計(jì)R .九江職業(yè)技術(shù)學(xué)院報(bào)告 2012 03.【5】陸柳延，王妹婷，齊永峰，呂學(xué)智，鍋爐水位的模糊控制及其仿真實(shí)現(xiàn) N 揚(yáng)州大學(xué)學(xué)報(bào)（自然科學(xué)報(bào)） 2013:02【6】馬躍春，基于plc的蒸汽鍋爐雙沖量水位控制J.科技信息 2013 ,10【7】張奠基 大容量鍋爐汽包水位的全程自動(dòng)控制J. 科協(xié)論壇 2013,09【8】郭慶祝 岳書朋 船用鍋爐水位控制系統(tǒng)J .中外船舶科技 2008,02【9】李成浩 鍋爐水位PID控制與模糊控制研究 J .2012,2110 Chen Ye, Cang Xiaojin, Peng Peng. Network control system based on OPC middleware technologyJ. Dianli Zidonghua Shebei/Electric Power Automation Equipment, 2011, 31: 100-104+108. 11 Xu Jianguo, Zhong Weimin, Tong Yu. Testing Platform for Advanced Process Control Algorithm Based on Matlab7.0 and KINGVIEWN. Chinese Journal of Scientific Instrument, 2006, 6: 542-544. 12 Li Anfu, Cui Yaling. OPC-based data communication between Matlab and KingViewJ. Electric Power Automation Equipment, 2007(7): 113-115.參考外文文獻(xiàn)及其譯文 Intelligent Control System of Water Level for Boiler Drum WU Mingliang1, WU Mingyong2, HUANG Jiankang3, SHAO Ling31. Electromechanical Academy, Lanzhou University of Technology, Lanzhou 730050, P. R. China E-mail: 2. Peili Oil Academy of Engineering , Lanzhou City Academy, Lanzhou 730050, P. R. China 3. Key Laboratory of Non-ferrous Metal Alloys and Processing under the management for Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, P. R. China E-mail: Abstract: WinCC configuration software and OPC technology as a breakthrough, communication integration of MATLAB and WinCC is realized. The real-time data exchange problem among different monitoring systems is solved based on OPC technology. That combine with strong engineering calculation ability of MATLAB and characteristics of real-time data collection for Siemens configuration software WinCC. The simulation results show that OPC is the communication interface between the Client MATLAB and Server WinCC. It can preferably realizes seamless transmission and experimental test of fuzzy self-adaptive PID intelligent control algorithm for boiler drum water level, and better satisfy real-time data, high efficiency requirements of process control for the boiler. Key words: OPC Technology, MATLAB, WinCC, Real-Time Data Exchange, Fuzzy Self-Adaptive PID 1 Introduction In the design of industrial boiler control system, how to effectively realize intelligent control algorithm is always the universal concern problem of the industrial boiler automation control areas. WinCC is the man-machine interface (HMI) software. It can solve visualization and control tasks in the production process and process automation, and develop acquisition system of supervisory control and data in the management level. It has high practicality and flexible configuration 1. But its ability of data processing is weak, and it is not easy to realize complex control algorithm. However, there are numerous advantages in MATLAB. For example, it is a kind of professional software for mathematical analysis and engineering computation, providing a powerful ability of data processing and open interface of application programming, having a rich toolbox of control algorithm, and completing modeling and simulation of dynamic complex control system. But WinCC cannot directly communicate with the industrial control equipment, carry on real-time operating and controlling, and effectively verify the algorithm. The OPC bases on a set of OLE and COM/DCOM technology of Microsoft Windows operating platform. It realizes standards of software interface between the different on-site equipments and applications. And it also adopts Client/Server model, in order to provide the highly effective information integration and object model component of standard interface of interactive function. Users design corresponding Client 2 ccording to OPC Server provided by hardware developers, and as a result the data exchange of different systems can be realized. If MATLAB is *This work is supported by National Natural Science Foundation (NNSF) of China under Grant 50675093. combined with WinCC by the OPC technology, complex control algorithm is used by MATLAB language, and then function of data acquisition and friendly human-machine interface are realized with WinCC, respective advantages of MATLAB and WinCC will be beneficial to be played. 2 OPC Interface Technology OPC (OLE for Process Control) is component model interface providing highly efficient information integration and interactive function for industrial applications. It is referred to object linking and embedding technology in process control. Due to maintenance and management of OPC Foundation institutions, the specifications of OPC DA (Data access), AE (Alarm and event) and HAD (Historical data access) has already been launched. At present, it is the most catholically applied that the OPC DA of data access standard. The standard is used to complete process of data exchange between process controller and HMI equipment or other clients. The datum read include data type, time label, quality and statement of numerical quality. The client can read the process data and write command into OPC server, and the command is transmitted to the scene controller3. The specification of OPC technology contains Server and Client, using the Client/Sever mode. Server is the supplier of data and Client is the user of data. They establish a complete set of rules between hardware supplier and software developer. The driver of hardware device and the communication program are encapsulated to independent OPC Server. It transmits control command and measurement data to Client. Only to obey the protocol of OPC data interface, OPC Client is generally designed and developed by the user. As a result, it can be realized that datum is acquired from OPC Client. An OPC customer can connect to one or more OPC Server, and multiple OPC Proceedings of the 30th Chinese Control ConferenceJuly22-24, 2011, Yantai, China4461customers are also allowed to simultaneously connect to the same OPC Server. Server consists of three types of objects: Server, Group and data Item, according to standard code of access for OPC data. Server has all information of Server objects and is a container of group objects, providing function of creating and operating the OPC group objects for OPC Client. Group has all the information of this group objects and is a container of OPC item, offering the mechanism of organization and management. Item is a specific process variable and the smallest unit of read-write, representing a physical connection which is from OPC Server to data source. Item cannot be directly accessed by OPC Client procedure but can be realized by accessing OPC group object containing items. Data structure of each data item contains three variables: Value, Quality and Time stamp. The OPC specification describes two kinds of access interfaces. They are Automation interface and Custom interface supported by OPC Server. The custom interface of OPC data access is a group of COM interface and can be developed and visited by high-level programming languages such as C/C + +. The realizable method of custom interface for OPC Server is complex, but fast and efficient. And the best performance of OPC Server can be exerted by this interface. However, the automation interface of OPC data visit is defined as standard interface based on scripting language of programming. It makes COM interface convert to automation OLE interface, and makes OPC server visited by expository language and macro language become possible. And it is developed and completed by senior languages such as Visual Basic. Moreover, the realization method of automation interface for OPC data visit is simple, but slow and has less function. 3 Fuzzy Self-adaptive PID Control of Water Level for Boiler Drum Presented The water level of boiler drum is an important parameter to ensure safety in production and provide steam of superior quality. Because many considerations such as load changes, inlet and outlet water speed and water quality influence the water level, it is a typically time-varying and nonlinear system. If a conventional method of automatic control is adopted, it often cannot be done that the desired control effect and the stability of drum water level. The accommodation of drum water level has certain characteristics of delay and inertia, namely, when step transition has taken place to the steam flow and water flow given, the water level of object regulated cant immediately follow with linear changes, especially there is a phenomenon of false water level when step transition has happened to the steam flow. Consequently, it is presented that fuzzy self-adaptive PID control of cascade three-level impulse module 4, 5 was adopted for the water level of boiler drum, and its scheme of control system is shown in Fig.1. Fig.1 Elementary diagram of fuzzy adaptive PID control for drum water level Inside the structure, the steam flow and water flow given which act on subloop at the same time arrive at phase equilibrium in the stable condition. But when one of them changes, due to the interference or spontaneous disturbance, the controller of water flow given for output will act on the actuator advanced regulating of water flow given and make water level invariant basically by conventional PID arithmetic, according to the deviation between the steam flow and water flow given. The parameter regulator in the first-order of major loop use self-tuning controller of fuzzy PID parameter. When the water level deviation is the given value, the adjustment value of water flow given is got by fuzzy PID arithmetic. Moreover, the water flow given controller changes water flow given, making water level return to the given value. 4 The Realization of Real-time Control on the Simulink and WinCC Between MATLAB and WinCC, the real-time transmission of data and seamless integration of system are designed and implemented. They provide intelligent control algorithm of designed calibration with an effective approach, playing an importantly practical value to field debugging of the boiler control. WinCC which can serve as either OPC Client or OPC Server has good openness and flexibility, can realize data exchange with external program safely and reliably and fully supports OPC standard. Through OPC- DA Server of WinCC, the real-time data in system of field process control can be obtained and related process variable value can be changed real-timely in system, completing effective control of system parameter 6. Fig.2 Structural diagram of MATLAB and WinCC process control 44624.1 System Structure System structure of realization process control for MATLAB and WinCC is shown in Fig.2. This system acquires data of field device with Siemens PLC S7-300 (lower computer), makes configuration software WinCC (host computor) act on the data total control platform and OPC Server and uses MATLAB as OPC Client for algorithm design, real-time control and analysis of control result. WinCC communicates with S7-300 through Profibus. 4.2 The Realization of Fuzzy Adaptive PID on Simulink and WinCC The Matlab7.0 above software has OPC toolbox which can undertake OPC Setting. Simulink7.1 integrates module sublibrary of OPC toolbox which includes OPC read block, OPC write block, OPC Configuration and OPC Quality Parts. MATLAB is used as a powerful Client, in order to realize analysis of control system, algorithm write and the graphic display of control algorithm effect 7. Using OPC Toolbox, dynamic data exchange of MATLAB and WinCC is realized, which has some main steps 8 as follows: (1) Commands of OPC register, OPC Server registered and the corresponding Windows core components used by Client are applied. (2) In the OPC Client and Server, proper DCOM configuration is carried on. Firstly, obtain node name in the network and guarantee the objects to join up in the OPC Toolbox and OPC Server. Secondly, download and install Client development kit including OPC Core Components 2.00 Redistributable 2.20.msi controls. (3) Open Simulink and find the module sublibrary of OPC toolbox in which the OPC read block, OPC write block and OPC Configuration are, these three modules are pulled to new model window. Double click the OPC Configuration, then choose and add OPC Server.WinCC to configure OPC Clients/Add/Select. Subsequently, double click to open Setting window of OPC Read parameter. First of all, OPC Server.WinCC is chosen and added through configure OPC Clients/Add/Select. Secondly, the shuiwei.cj, shuiliuliang.cj and zhengliuliang.cj of localhost/OPCServer.WinCC are selected in “Add Items”. In the same way, add qishuiwei to OPC Write. Note that other parameters in the OPC read and OPC write are set for Synchronous (de-vice) and Sample time is 0; synchronous communication mode is chosen in the Write mode and Sample time is set for 0. (4) In OPC Server WinCC, create variables, establish OPC driver, set related operation parameters and ensure that OPC server is running when mutual communication. The real-time control system in Simulink is shown in Fig.3. It mainly includes three parts: OPC read block (acquisition value of real-time read), cascade controller of fuzzy self-adaptive PID and OPC write block (control variable of real-time). WINCC display picture of reading and writing data, and real-time datacurve of OPC communication in MATLAB OPC Server are shown in Fig.4. It could be seen from this curve that according to the operation state, the system adjusts three parameters of the PID controller on line such as Kp, Ki and Kd, makes control system have good dynamic and static performance index in order to achieve optimization of system performance index and overcome unmodifiable disadvantages of traditional PID controller parameters. Fig.3 Block diagram of Simulink control system Fig.4 Real-time data curve of WinCC data display and OPC communication 5 Conclusions Through establishing a simulation model of OPC technology, corresponding control algorithm of OPC Client established in Simulink communicates with OPC DA Server of industrial control software WinCC, obtains object process data and controls the corresponding boiler equipment in the WinCC. In simulation system, various control algorithms are edited by MATLAB, and measurement verification is directly carried out through this Client/Server mechanism. So not only actual performance of control algorithm can be inspected, but also more importantly debugging data and information can be got for the system commissioning operation to provide important reference. Engineering practice shows that this method realizes the system intelligent control without increasing any system cost, has some advantages such as high control accuracy, good stability and short development cycle, and is a beneficial attempt of intelligent control realized for engineering method. The engineering method offers a new 4463way of thinking for application of intelligent control algorithm in industrial control process. 1 Weng Yifang, Duan Zhenqang, Lian Xiaoqin. Application of configuration software WinCC in logistics automatic control system. In: Sixth International Symposium on Instrumentation and Control Technology: Sensors, Automatic Measurement, Control and Computer Simulation, vol. 6358 , 2006. 2 Oh. Se-Young, Kim. Wan-Ho, Yune. Hyoung-soon: The double exposure strategy using OPC & simulation