包子开题报告

1、毕业设计（论文）材料之二（2）本科毕业设计(论文)开题报告题目：基于西门子PLC S7-200的凝汽器胶球清洗系统 课 题 类 型：设计 实验研究 论文学 生 姓 名： 包子学 号： 3060201233专 业 班 级： 自动化062班系 别： 电气系指 导 教 师： 宋晓庆开 题 时 间： 2010.4.19 2010年4月 19日一、 毕业设计（论文）内容及研究意义（价值）本人于2010年3月3日在北京正东集团动力南厂实习。动力南厂是一座以天燃气为燃料的发电和供热厂，该工程作为热电联产形式，与单发电相比利用率高，燃气轮机蒸汽轮机联合循环机组及热水锅炉的综合热效率为71.1%。现场的设备中多

2、处运用了西门子PLC技术，很多设备用的甚至都是西门子S7-300和S7-400这样的新型技术，并且即将在四月份邀请西门子培训公司来南厂就PLC技术作相关的培训。毕业设计论文做凝汽器胶球自动清洗系统课题可以充分的体现理论联系实际，将课本所学的知识充分的运用到生产实践中来并且得到深层次的延伸。凝汽器胶球自动清洗装置系统是保证汽轮机凝汽器长期稳定高效工作、安全经济运行的重要设备。采用本装置可以在机组不减负荷的情况下，对凝汽器管子内部的污垢进行自动清洗，从而提高凝汽器铜管清洁度，改善凝汽器真空，降低温度端差，避免垢下腐蚀，延长铜管使用寿命，提高换热效率。使用该装置是实现火力发电厂安全、满发、经济运行的

3、有效措施。其工作原理是将密度近似于冷却水、湿态直径大于冷凝器管12mm的海绵胶球,靠循环水力携带进入凝汽器水室，通过凝汽器热换管，达到在线清洗凝汽器管的目的。该设备可以广泛应用于电力、冶金、化工、矿山等行业，是一种高效的节能设备，设备整机寿命约30年，约5-6年可以收回全部成本。凝汽器是火力发电厂、核电站及化工企业的重要设备。凝汽器的作用是在汽轮机排汽口建立并维持高度真空，将汽轮机的排汽凝结成洁净的凝结水作为锅炉的给水循环使用，长期使用的情况下会有水垢等污垢破坏腐蚀管道，所以需要清洗。采用胶球自动清洗装置，西门子PLC控制，收球率高而且方便。胶球清洗系统作为提高汽轮机组热效率的重要辅助设备，可

4、帮助维持凝汽器冷却水管内壁的洁净，提高凝汽器总体传热性能，从而使凝汽器保持较高的真空和较小的端差，因此为国内外电厂普遍采用。它的根本任务是保证胶球的正常循环，使胶球能够顺利输出并回收。二、 设计（论文）现状和发展趋势（文献综述）：胶球清洗技术于本世纪50年代初由前西德人塔布诺格所发明。首先在 西德使用，并成立了塔布诺格公司。该项技术问世不久，就以它独具的优势引起了世界各国同行的重视。胶球清洗技术在国内试验、研究起步较晚，但通过国外先进技术和经验，并结合多年的实践对产品的不断改进、完善使产品在设计、制造、投运等方面积累了丰富的经验，目前，我国产品的设计、设备性能均接近世界先进水平。胶球清洗装置是

5、汽轮机发电机组在运行中对凝汽器冷却管进行有效清洗的最佳设备，该装置使用性能的好坏，直接影响到凝汽器的清洁程度和传热效率，是提高电厂经济性，保障凝汽器安全运行不可缺少的设备。它的优点有结构设计新颖合理，操作方便，胶球回收率高（大于等于96%），二次滤网过滤能力强（有卧式或立式，手动或电动型式）。凝汽器胶球清洗装置的工作原理：选用合适的海绵胶球，球的湿态直径比冷却管内径略大一点（约1-2mm），且湿态比重和水相近。将胶球投入装球室内，数量为凝汽器进水室铜管数的10%左右。然后启动胶球泵，打开系统两端球阀，胶球就在此循环水进口压力差的作用下，被挤压通过冷却管，对冷却管内径进行一次抹擦，使管内壁污垢随

6、水流带出，胶球随循环水经出水管进入收球网，在收球网板的阻拦下，把胶球分离出来，由胶球泵抽出重新回到装球室，如此循环往复对凝汽器冷却管实现连续自动清洗。它包括二次滤网，收球网，装球室，胶球泵，分汇器，控制柜，阀门和管路。胶球清洗技术应用后的节能效益：据江苏省电力局生产处资料，NZSW机组，凝汽器真空度每降低1%，供电煤耗上升5.549/k.N300W机组，凝汽器真空每降低1%，供电煤耗上升3.609/kwh，N25W机组端差增大1C（夏季/冬季），供电煤耗上升2.78八.22g/hvh.N300W机组端差增大1C（夏季/冬季）供电煤耗上升1.93/0.859/kwh。采用胶球清洗技术，可清除或减

7、少冷却管内污垢，降低凝汽器端差，提高凝汽器真空，故可大量节约燃料。由于采用胶球清洗系统，能提高凝汽器真空及机组出力，这对过夏天困难的机组尤为重要。例如，德阳火电厂以前夏季每天都需降负荷清理二次滤网，更改了胶球清洗装置后，免去了人工清理二次滤网，且机组均超负荷发电，轻松过夏天。三、毕业设计（论文）研究方案及工作计划（含工作重点及拟采用的途径）研究方案： 本课题研究的是凝汽器胶球自动清洗装置系统。本清洗装置是由程控器自动控制的，当凝汽器铜管需要清洗时，程控器通过人工清洗指令PB101，PB102（预先由用户设置的），依次开启或关闭相应执行机及胶球泵，完成一次清洗过程，各执行机动作开关状态指示在动态

8、模拟屏上。通过编程修改可改变自动清洗时间，通过转换主令开关可以实现手动清洗或自动清洗。当程控柜安装调试完确定无问题后，投入电源，按相应侧胶球启动按钮PB101或PB102，程控柜按要求完成一次一侧胶球清洗过程。若要继续清洗另一侧，需按另一侧胶球启动按钮。PB102 PB202为每次胶球清洗停止按钮。本胶球系统两侧共用一套胶球清洗，因此每次只能清洗一侧，手动操作分配器及球阀时应分清相应侧。研究的重点与难点:1. 凝汽器清洗装置应有手动/自动切换装置以方便运行人员应能做到一键自动完成清洗并提高收球率。2. 采用西门子S7-200控制，应实现就地/远方的操作同时为了减少连接导线，使用ModBus与D

9、cs通讯，通过组态画面便于运行人员监视清洗过程。拟采用的途径:1. 查阅相关资料，掌握凝汽器胶球自动清洗装置系统的相关理论知识。2. 编写该系统的PLC程序，并核对校验。3. 到现场参观了解该系统的实际应用，实现设计的程序的可行性。工作计划：2/25-3/2 查阅相关资料（图书馆资源和网上检索）3/2-3/9 整理资料，明确课题内容3/10-3/16 了解凝汽器胶球自动清洗装置系统3/17-3/27 理清思路，设计实现方案，准备开题报告3/28-3/30 整体上熟悉胶球凝汽器胶球自动清洗装置系统3/31-4/6 了解和认识凝汽器的运用以及清洗的方案4/7-4/13 了解胶球系统工艺要求整理编程

10、思路。4/14-4/20 复习电气原理，继电器知识，电机正反转控制以及电动门常识。4/21-4/27 PLC，ModBus通讯方法以及Dcs简单组态。4/28-5/4 复习PLC软件的编程方法回顾和学习PLC相关知识5/5-5/11 根据资料和设计的方案编写出相关的PLC程序5/12-5/18 反复调试程序并验证程序的可行性5/19-6/1 现场实地的操作和实现该清洗系统的功能6/2-6/15 撰写毕业论文6/16-6/22 毕业论文答辩6/23-6/29 完善毕业论文四、主要参考文献1 吴一平，周定国.凝汽器钢管氨蚀的研究，腐蚀与防护.19922 沙占友，薛树琦，葛家怡.湿度传感器的发展趋势

11、.电子技术应用，2003，(7)：6-7 3 李培元.火力发电厂水处理及水质控制.北京：中国电力出版社，20004 王杏卿.热力设备的腐蚀与防护.北京：水利电力出版社，19885 韩中合，田松峰，马晓芳.大型火力电厂生产技术人员培训系列教材：火电厂汽轮机设备及运行.北京：中国电力出版社.20026 江苏省电力局.凝汽器的胶球清洗.北京：水利电力出版社.19797 武汉水利电力大学化学教研室，火力发电厂水处理.北京：水利电力出版社.19858 齐占庆，王振臣电气控制技术 M北京: 机械工业出版社，20029 苏国民,何勇华,黄曾.基于PLC控制的泵站自动控制系统的应用.华煤矿机电, 期刊.200

12、8-04-15 10 卞和营,胡亚卓.继电器控制系统改用PLC控制的设计方法.科技资讯, 期刊,2007-12-13 11 周敏,李凤婷, 吴为民.基于PLC控制的火工企业气动顺序控制系统的研究.工业控制计算机, 期刊,2007-11-2512 耿良田. PLC的现状及发展趋势J. 数字化工 , 2005,(08) . 13 米红艳. PLC系统的应用与发展J. 洁净煤技术 , 2005,(04) . 14 张东明,文友先. PLC的发展历程及其在生产中的应用J. 现代农业装备 , 2007,(09) . 15 潘勇,高俊雄,王耘波. PLC的应用和发展J. 计算机与数字工程 , 2007,(

13、02) . 16 王兆义,陈治川,王生学. PLC发展的几个特点和国产化J. 自动化博览 , 2006,(S1) . 17 姚栋,信明阳. PLC应用及其发展J. 科技咨询导报 , 2007,(19) . 18 廖常初. PLC的发展趋势J. 电气时代 , 2003,(12) . 19 Shigeki Kiyonaka; Kenta Kato; Motohiro Nishida; Yasuo Mori, Yakugaku Zasshi,Pharmacological Properties of Novel TRPC Channel Inhibitors,;Vol.130 No.3,2010 P

14、age 303-31120 Sanjay Jain; Amanda Knoten; Masato Hoshi; Hongtao Wang; Organotypic Specificity of Key RET adaptor-docking Sites in the Pathogenesis of Neurocristopathies and Renal Malformations in Mice,JournalofClinicalInvestigationVol.120 No.3 Mar 2010 Page 77879021 Haba, C.-g, Extending the Use of

15、PLC Simulator Software in Student Laboratory Works, Advances in Electrical and Computer Engineering ;Vol.10 No.1 Feb 2010 Page 84-89附录：英语引文及翻译Improvement of equipment for the ball-cleaning system of steam turbinecondensers Summarize:Generally, scale formation can be found in the tube of condenser ea

16、sily, the clogging of tube can lead to the pressure increase by several mbar, so the energy output of generating set can be lost by several MW, thus, the condenser is considered as a key equipment in large-scale power plant, the improve of working efficiency of condenser can improve the thermal effi

17、ciency of the whole generator set.Working principle：The KNJQ-11 type condenser rubber-ball cleaning device is made up of rubber-ball cleaning device and intelligent control system.Use flexible rubber-ball whose diameter is a little bigger than ID of tube to pass through the tube of condenser, the in

18、jection water-flow can be present on in front of rubber-ball, at the same time, the rubber ball rubs against the tube wall so that the fouling can be removed. Thus, the whole system can be kept under normal operation. There are many key technologies, suck as good ball-retraction rate、stable rubbing

19、against wall and even cleaning frequency to each condensing tube.As a sign for the advantage of one control system, through online monitoring for working state of condensation tube and temp of inlet/outlet as well as the flow pressure and alike, work out the scale depositing thermal resistance by ma

20、thematical model, then transferred into cleanness index so that the operator can know the scale depositing state, then work out the optimum washing cycle according to economic loss and washing cost.The efficiency and reliability of steam turbine unit (STU) operation are to a great extent determined

21、by the condition of the turbine condenser and the quality of its servicing. Deposits of organic and/or mineral origination always exist on the water side of the condenser tubes. Tubes and tube desks are also fouled by mechanical admixtures.All the above leads to deterioration of the heat-transfer ch

22、aracteristics of a condenser, increasing of the pressure drop, and enhancing erosion and corrosion processes. Therefore, it is necessary to periodically or permanently remove these deposits and large mechanical admixtures. Periodically cleaning by mechanical, thermal, or chemical methods does not co

23、mpletely solve the problem of preventing deposits, because between sequential cleanings inevitable fouling of the condenser takes place that causes vacuum deterioration and a decrease in the STU efficiency. For this reason, in principle, it is more effective to implement preventive measures that exc

24、lude condenser fouling. Maintaining the condenser in a clean condition is one of the unbiased indexes of a high culture of STU servicing. Many years of experience show that the most efficient preventive measure that provides cooling-surface cleanness is cleaning the tubes with porous rubber balls in

25、 the course of condenser operation. Installation of the system for ball cleaning (BCS) of the condenser and filters for additional cleaning of cooling water in an STU makes it possible to maintain the condenser in a clean condition and obtain additional power, due to operation with a higher vacuum.

26、The ball-cleaning system is excellent from the environmental point of view. Therefore, in addition to an increase in the STU efficiency by 12%, it enables us to increase the reliability of operation. For example, studies of the corrosive damages to condenser tubes (these tubes are made of MNZh5-1 al

27、loy) caused by microbiological processes have revealed that the most effective way to increase their corrosion resistance and corresponding lifetime is the application of rubber-ball cleaning.In this paper, it has been also pointed out that, in the condensers, which are not equipped with BCSs, to re

28、duce failure of tubes, it is necessary to install filters for additional cleaning of cooling water upstream of the condenser.In addition to the apparent savings of fuel and corresponding decrease in harmful emissions of NO and SO the introduction of a BCS and filters makes it possible to maintain th

29、e hydraulic resistance of the condenser at a minimum level. This increases the reliability of operation of circulation pumps and excludes additional. Expenses for pumping cooling water, thus decreasing costs for using water.In the domestic power industry, the use of BCSs and filters started as early

30、 as in the middle of the 1980s,when a license and technological line for manufacturingporous rubber balls was bought at the company .Taprohee (Germany). The manufacturing process was perfected at ZAO Uralelastotekhnika (Yekaterinburg).While developing the first examples of domestic equipment, foreig

31、n design decisions known at that time were applied. These decisions were adopted to the specifics of the water-supply-line arrangements and technological possibilities of the manufacturer. In the course of mastering this equipment at power plants, several shortcomings were recognized. These included

32、, in particular, an increased hydraulic resistance of filters and ball-catching grids, low effectiveness of methods applied for cleaning filters from mechanical admixtures, and intense wear and loss of balls from the circulation circuit. In VTI, bench and industrial studies were conducted aimed at t

33、he creation of reliable BCS equipment and filters.On the basis of these studies, original domestic designs were developed that have patent cleanness and outperform foreign analogs in simplicity and lower cost. On the license basis, these devices were transferred to the GRES-24 Power Plant, affiliate

34、d branch of OAO Mosenergo, where, starting from the beginning of the 1990s.翻译：胶球清洗系统的设备改进概述：一般来说在凝汽器的管道里很容易的可以看见有很多的细管道，管道的阻塞可导致压力增加好多毫巴，所以发电机组输出的损失可以达到好几兆瓦，因此，凝汽器被认为大型发电厂的重要设备，其工作效率的提高可以提高整个发电机组的热效率。工作原理：KNJQ - 11式凝汽器胶球清洗装置是由球清洗装置和智能控制系统组成。使用直径比管身编号要求小的灵活的橡胶球来通过凝汽器的管道，注入的水流在胶球的前方流动，同时胶球与管壁摩擦，这样就可以清

35、除污垢。因此，整个系统能够维持正常运作。这里有许多关键的技术，如球的良好回收率，对管壁的稳定摩擦，甚至每个凝汽器管道的清洗频率。作为控制系统先进性的一个标志，通过在线监测凝汽器管道的工作状态和进出口温度，像流动的压力一样，用数学模型计算出大量的热电阻的值。然后转换清洁度的指数，使操作者知道沉积状态的规模，然后根据经济损失和清洗费用制定出最佳的洗涤周期。汽轮机组运作的可靠性和效率在很大程度上由汽轮机凝汽器的条件和其运行的质量决定。有机矿物质总是存在在的凝汽器管道的水里，管道和管道壁也总是被其堵塞。上述所有导致凝汽器传热特性恶化的因素，增加了压降，加强了过程的侵蚀和腐蚀。因此，有必要定期或永久的删除这些沉积物和大量的机械杂质。定期的用机械，热，化学的方法不能完全解决防止沉积物的问题，因为顺序的清洗不可避免的污垢将导