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关键词：: S7-200 PLC控制变频调速恒压供水系统设计 cad图纸西门子PLC 程序毕业论文变频调速恒压供水 S7-200 PLC控制

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S7-200 PLC控制的变频调速恒压供水系统设计

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S7-200 PLC控制的变频调速恒压供水系统程序.mwp

S7-200 PLC控制的变频调速恒压供水系统设计开题报告.doc

S7-200 PLC控制的变频调速恒压供水系统设计文献综述.doc

S7-200 PLC控制的变频调速恒压供水系统设计论文.doc

S7-200变频调速恒压供水系统系统图.dwg

任务书.doc

外文翻译--恒压供水的控制与节能的探索.doc

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摘要

传统的供水系统存在着占地面积大、建设费用高、管理维护复杂困难、供水质量低下等缺点和不足。为了解决这些问题，本文采用控制技术和变频调速技术相结合的方法来研究恒压供水系统，该系统与现场液位传感器、压力传感器一起组成了两个独立的闭环控制子系统。设计好的系统每天24小时不间断按预先设定的水压恒定地向城市供水，保证了水厂的不间断生产。

通过该项目的研制和应用，不仅能够节约宝贵的水、电资源，降低了生产成本，减少设备维护，降低维修成本；而且提高了整个水厂的生产调度管理水平，减轻工人劳动强度，有效的提高了生产率。

关键字：恒压供水，控制，变频器，

ABSTRACT

Traditional water supply system has the shortages including occupying wide surface area、high expenses、management complex and difficult、water pollution again, and so on. In order to solve these problems, this paper combines control technology and transducer technology to research constant pressure water supply system. Two independent sub-systems are irrespectively built with water place sensor and pressure sensor. The finished system can fulfill constantly supplying water to city day and night according to the water pressure given to assure the continuously produce.

With the research and use of this project, we can save large sum of precious water、electrical source, and decrease the produce price, reduce device management and lessen repair price. Moreover, this system also can improve the lever of produce and management, lighten the work’s strength, and increase the productivity

Key Words: constant water supply system, control transducer,

第1章绪论1

1.1 采用恒压供水系统的目的和意义[1、2、7、9]1

1.2 恒压供水的特点1

1.2.1 恒压供水方式讨论1

1.2.2 恒压供水的实现2

1.3 现行高楼供水的模式[19]2

1.3.1 恒速泵供水2

1.3.2 高位水箱供水2

1.3.3 气压罐供水3

1.4 毕业设计的主要任务3

第2章变频调速恒压供水分析4

2.1 变频恒压供水的工艺调节过程介绍[6]4

2.2调速系统的构建[25-29]4

2.2.1 调速原理4

2.2.2 恒压供水系统的组成5

2.2.3 调节系统的计算方法[12、13]5

2.2.4变频恒压供水频率变化分析7

2.3 节能分析[3]8

2.3.1 水泵的基本参数和特性[14-18，36，37]8

2.3.2 水泵调速运行的节能原理11

第3章恒压供水系统13

3.1 系统概述[31]13

3.2 控制系统的组成13

3.2.1 供水系统的组成13

3.2.2 系统功能说明13

3.3 恒压供水系统的机理及调速泵的调速原理14

3.3.1 恒压供水系统的工作原理14

3.3.2 调速泵系统构成14

3.4 变频器[6]14

3.4.1 变频器输入输出接口14

3.4.2 变频器外围设备的选择及保养15

3.5变频调速恒压供水系统的特点16

第4章可编程控制器PLC17

4.1 的定义[20-22]17

4.2 的发展阶段及发展方向17

4.3 的特点与应用领域18

4.3.1 可编程序控制器的特点18

4.3.2 可编程序控制器与继电器控制系统的比较19

4.3.3 可编程序控制器的应用领域19

4.3.4 在现代自动控制系统应用中所面临的问题20

4.4 我国常用的性能比较研究20

4.4.1 的一般结构20

4.4.2 基本工作原理22

4.5 我国常用的性能特点23

4.5.1 SIMATIC S7系列 [24]23

4.5.2 S7-200系列可编程序控制器23

4.5.3 控制系统设计内容24

4.5.4 控制系统设计步骤24

4.5.5 控制系统的硬件设计25

4.6 控制系统的软件设计26

4.6.1 软件设计概述26

4.6.2 软件设计27

4.6.3 程序设计的常用方法28

4.6.4 程序设计步骤29

第5章 PLC控制系统的设计31

5.1 概述31

5.2 输入输出分配31

5.2.1 输入口31

5.2.2 输出口31

5.2.3 辅助触点31

5.3 控制系统功能介绍32

5.4 恒压供水系统的流程图33

5.5 控制系统的可靠性及应用程序设计34

5.5.1 程序的优化设计34

5.5.2 应用程序的设计35

5.5.3 故障检测程序的设计37

第6章系统调试38

6.1 变频器关键参数的设定38

6.2 的调试38

致谢43

附录 PLC程序44

1.3.2 高位水箱供水

采用电流及电压的相位大小等变化特性对高位水箱泵组进行控制。供水系统利用高位水箱及地下水池的水位变化来自动启闭水泵，以向各水箱供水。改供水方式可控性差。

1.3.3 气压罐供水

气压供水设备是利用压缩空气的涨力将水送往用水点的通用供水设备。气压供水整套设备高压密封，没有外部污染，内部不长青苔。并且供水压力可以根据需要很方便地在控制器上进行调整，不象高位水箱当放置的高度确定后，水压就已确定，无法调整。但是气压供水能耗大，且控制水压能力有限，不如水泵供水的压力控制。

1.4 毕业设计的主要任务

随着变频调速技术的发展，变频恒压供水系统已逐渐取代原有的水塔供水系统，变频恒压供水已广泛应用于厂矿企业及生活、消防等供水系统。

S7-200控制的变频调速恒压供水系统采用变频调速方式自动完成泵组软启动及无冲击切换，自动调节水泵电机转速，改变以往“先启后停”方式，使水压平稳过渡。采用硬件/软件备用及时钟控制功能，使各泵进行轮休，延长设备的机械使用寿命。变频器故障时系统仍可运行，保证不间断供水。从以上各图可以看出调节之后的效果。

图6-1可以看出系统的稳态误差。

图6-2可以看出图1系统的各参数。

图6-3、6-4可以看出调节的效果，系统的输出随中间变量的变化而变化。

调试过程

本次设计我是在浙江工业大学浙西分校信电系一楼过控实验室进行调试的，起初程序并没有现在复杂，一开始只有8个子程序，一个中断，而现在有12个自程序，每个子程序都有各自的功能上面都已经介绍过了，下面我介绍以下调试时遇到的问题好。

例如：课本上的置位与复位，只需要写SET或者RESET，再标注哪一个触点就可以了，但是在-7中编辑程序时，在置位与复位下面还有一个数字，一开始始终不了解这个数字是干什么用的，一开始始终认为是要置位到1，或者复位到0，所以一直再下面输1或者0，但是程序总有错误，上网查资料，再查说明书，再加上不停的调试，总算知道这个数字是表示从该触点的内存位置开始置位或者复位多少位。

再如，起初我在程序中大部分使用的是输出，而不是置位，但是经过调试之后我发觉有些位置使用输出是不行的，例如加泵子程序中因为使用了许多互锁，因为这些互锁的原因，程序也修改了多次。

面对上述以及许多零星错误，自己的失误，和对部分数据判断的错误，我经过不懈努力，多次尝试，以及指导老师的讲解，终于全部克服，完成任务。

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内容简介：: 浙江工业大学浙西分校信息与电子工程系毕业设计（翻译资料）English Part毕业设计(论文)翻译资料信息与电子工程系工业电气自动化专业 04 级 1 班课题名称：S7-200 PLC控制的变频调速恒压供水系统设计毕业设计(论文)起止时间：2007年3 月1 日6 月10 日(共17周)学生姓名：赵晋学号： 3040221123指导教师：黄云龙、朱秋琴、廖东进报告日期： 2007-3- The control and Energy-saving of automatic Water Supply SystemAbstract: Based one simple analysis of the methods for water supply used domestically and abroad, this paper discusses the principe and systems structure of automatic water supply system by using frequency conversion speed regulation in detail. Then the systems advantages are discussed and some key problems that should be pay attention to designing are presented.Keyword: Frequency conversion speed regulation; water supply with stable pressure: PID regulator.1、 ForewordAt present , supply water in residential area and life of the skyscraper of our country generally adopt the way common frequently . It has heavy energy consumption, high noise ,and there has a great deal of questions in the source of water, such as secondary pollution etc. And it is a kind of comparatively ideal mode to adjust the watersupply device controlled rapidly with frequency conversion .Entering the middle and later periods of the 1990s, as the speed technology of frequency conversion achieves more development becomes perfect, the way of the full-automatic constant pressure that based on this technology supplied water has already been widely used in the developed country , and is becoming riper.In recent years, author has made some real work on rapidly to the transformation in frequency conversion supply water design and construction of control system , have accumulated some experience, and has formed the view on some questions. The reason why the energy-conserving principle frequency conversion of the water pump system of speed adjustmentbecomes popularized , is mainly because that it has a better energy- conserving result. To pump system of frequency conversion, the water pump after adjusting the speed has functional relation of the following:Q1/Q2 =n1/n2(1) H1/H2 = (n1/n2)2(2)of the type. Q1, Q2 represents the flow before and after the speed for the water pump respectively; N1, n2 represents the rotational speed before and after the speed for the water pump respectively; H1, H2 represents the lift before and after the speed for the water pump respectively . According the above:H1/H2=(f1/f2)2Namely real lift of a water pump is power the square offrequency in direct radio. Therefore changing the power supply frequency of the electrical machinery of water pump through the frequency converter , can control supporting water pressure strength of the water pump . 2 constant pressure as Fig. 1 shows supply water of the automatically controlled frequency conversion water -supply system principle block diagram. P1is the give pressure value, p2 for the actual pressure value had examined from the pipeline of the pressure sensor, PID regulator passes the error operation of the two value, and through controlling the frequency output of the frequency converter, thus make the pressure of the pipeline remain throughout on establishing value p1.This system can measure users instantaneous water pressure adjust automatically, regulate the amount of quantity of supplying water and operation conditions of the electrical machinery in view of the above. Can according to give water pressure strength to set for and control pressure value which needed , make the equipment in the constant pressure state all the time, can know from load characteristic of electrical machinery axle power and its the third power of in direct radio rotational speed of electrical machinery mixed, that is p1/p2=(n1/n2)3. For example, as the frequency converter output frequency for 35Hz (establish as 50Hz at most), that is to say that the actual rotational speed is 70% oclock of specified rotational speed, the power consumption of the governor is 0.73 =0.343, account for specified 35%. That is to say , the water pump is always in constant pressure and turn the working state of matching the way into the flow , is it is it keep to exceed to dispel and backset current have work loss. Constant speed transfer with frequency conversion speed axle power change curve as Fig. 2 shows , relatively can know, it is the most obvious that frequency conversion adjusts the energy-conserving result of speed way.2、 Caseanalyse Constant pressure is it regulate flow of water to the purpose to up to constant pressure through suiting well rapidly in frequency conversion to supply water, the goal that it controls finally is the water pressure. Controlling the target has non-linear , lagging characteristics. The quality of PID regulator performance , has determined the quality of the water -supply system to a great extent When the system is during the course of starting and stopping, or the pressure establishing value changes by a large margin , because there is a very great deviation within short time, no matter the controll algorithm of PID regulator adopts the increment type or the position type, its total mark one will fetch the cistern , water pump group (1M , 2M ) and complement the fittings to form relevantly. The core of this system is that frequency conversion adjusts the speed switch board, it monitors the pressure of the pipe network in real time through the pressure sensor , and change into the electric signal and offer the frequency converter to to make operation, through the controlling commonly of frequency converter , programmable controller PLC and relay array, adjust the system of supplying water rapidly after forming perfect full-automatic frequency conversion.Frequency converter is various in kind, for instance the types , such as Mitsubishi , Fuji , three Kenya and ABB ,etc. Generally often select the pumps , special-purpose series of air blower for use. Whether take Mitsubishi FR-A140E as an example, it except general function had of brand , there are the following characteristics : The inside adopts the intellectual power module of IPM, it is lowest to make the noise of the electrical machinery to reduce; Frequency converter, and work-frequency power can is it switch over to go on frequently, user is it is it start , stop through PLC and switch over the order automatically to input to need only, can conveniently through to lock movement switch over different water pump each other contactor, and does not need to design the tedious control procedure by oneself like the thing that in the past , this is one of this peculiar functions of frequency converter; Built-in instantaneous power cut starts and retries and starts the function , in a situation that nobody guarded, even if can be started by oneself after the frequency converter shuts down, totally realize with the operation of the automatic way. PID regulator available frequency converter of system this built-in value very heavy, this will store deviation in regulate. During the process of dispelling the deviation to regulate , must lead to the fact the system and present greater ultra mediation long-time vibration , can produce the serious integration saturation phenomenon also at the same time , thus influence the normal running of the equipment. Is it drop the influence to most low to want , should adopt PID control method that integration separate among controlling algorithm, in order to reach the anticipated result. After dealing with like this , can shorten the system and reach steady transition course time greatly System allocate two 11kW water pump support 600 over resident water. Two pump offer large peak flow most when working at the same time, single platform meet the small flow and supply water at night. In addition all water pump can run by way of frequency conversion , can circulate way soft to start, in this way , can reduce the impact to the electric wire netting and pipe network . What merits attention is two pump when frequency conversion and worker are switched over frequently , have procedure it locks to be enough each other only, outputting must adopt machinery to interlock the contactor , can avoid the situation that two contactors close at the same time in the twinkling of an eye in this way, so as not to short out in twinkling of an eye causing power .pressure sensor P monitors the size of the water pressure signal in real time, the signal is dealt with by PID, input it to the frequency converter. At the small flow, water pump electrical machinery 1M turn round (whether 1KM1 is it shut to suck), and through feedback password change his rotational speed constantly, it is invariable in order to keep the pressure; In case of large flow , compare frequency conversion by pressure circuit send out through PLC constant/changed switch over frequently operate and interlock the order, machinery interlocks the contactor ( 2KM2 in 2KM (2KM1 +2KM2 ), contactor 3KM have the electricity. At this moment, electrical machinery 2M is started by way of frequency conversion, 1M is switched over and run at full speed frequently to run . In this way, this system can maintain water consumption on a invariable pressure all the time . Built up in the aforesaid district initial stage , supply water and adopt the way frequently of workers, because of energy consumption being heavy dependability is bad, the household reflects strongly. Use instead after frequency conversion supply water, installation total capacity reduce 25% than original equipment , economize on electricity the index is close 30% synthetically actually, the result is remarkable.3、 Several questions while apply are in case of great majorityThe environment for use of the scene is comparatively abominable . Though frequency converter has very strong protection functions itself, such as owe keep , excessive pressure , is it flow to pass, electric current amplitude limiting is it make exactly to choose, overload, overheated lacking looking , shorting out and disconnected ink protect the function But must prevent trouble before it happens . Through using finding , two kinds of brands of Mitsubishi , Fuji, because has fully considered various kinds of abominable running environment in design and manufacture. The dependability and service life under the same condition are higher than some brands. One small city of mountain area of west place in Hubei in Hubei, average 1200m above sea level, the humidity on the high side of long-term most of the time (about 80%), the sulfur dioxide is seriously polluted, a set of frequency conversion that one factory produces supplies water of the equipment, because has not considered above-mentioned factors , less than one year, the relevant parts of the equipment are corroded seriously. And the like product which we designed , installed in the same area, because has fully considered the situations of different difference, on the selecting types of the equipment and component , have adopted the ship standard. Through the use of more than two years , ran well , stood the tests of different sternness. Find in using actually , the frequency converter itself is that a strong interference takes place in the source , will often influence the normal running of the equipment. Especially when the low rotational speed of the water pump operates, the frequency shown on the frequency converter does not correspond to actual operation frequency. Generally there are two kinds of spread ways to interfere: The circuit bunch is disturbed and space radiation is interfered. Can take the corresponding measure to solve according to the actual conditions of the scene. For example is it strain wave and absorb the return circuit to increase to programmable power end of controller, PID regulator introduction of unit output sure to have reliable shielding , link frequency converter , ground terminal of electrical machinery with earth stake firmly, control the line and motive force line leave certain distance , in order to strengthen and resist the electromagnetic ability to interfere. Only in this way ,can make system keep the long and steady working state in high temperature , humidity , mould , strong harsh terms of interfering etc.4、 ConclusionsAre by way of adjusting the speed as the central water supply in frequency conversion, the result is obvious to economize on water , economize on electricity, can be extensively suitable for 20-10000 residents the biotope , skyscraper , hotels and retaurants , fire control or district pressurize and supply water, it is ideal facilities that the medium and small- scale waterworks supplied water too. Its amount of water quality supported is high, the economic benefits are obvious, the social benefit is enormous, with the development of national economy and constant improvement of the living standards of the people, it is sure to be used and popularized progressively in our country5、 List of references Zhang Wanzhong, Zhu Jie, Wang Mingquan. A kind of new-type frequency conversion constant pressure supplies water of the plan of design of the pump station. Electrical age, 1999 (10): 22-232Liu YingChun. Principle design of the sensor and application. Beijing: University of Science and Technology of the national defence publishing Presss, 1989.59-623Lu Guangda. Electric installation project manual of the building . Beijing: The electric publishing house of water conservancy, write the group in 1995.222- 2244 The automatic projecting . Give and drain off water the automatic project. Beijing: The electric publishing house of water conservancy, 1997.301-312恒压供水的控制与节能的探索摘要:在简要分析国内外给水系统现状的基础上,介绍了系统的组成,提出了以变频调速为核心所构成的全自动给水系统控制方式,并以实例详细分析了该系统的组成、工作原理以及在控制与节能方面所表现出的优越性.文中根据作者的实际使用经验,简要阐述了该系统在应用中应注意的一些问题。关键词: 变频调速;恒压供水。PID调节器中图法一、引言目前,我国居民小区与高层建筑的生活供水,普遍采用工频方式.它存在着能耗大,噪音高,水源存在二次污染等诸多问题.而用变频调速控制的给水装置是一种较为理想的模式.进入90年代中后期,随着变频调速技术的不断发展与完善,基于该项技术的全自动恒压给水方式已在发达国家得到广泛的应用,且日趋成熟.近几年来,作者在变频调速给水控制系统的设计与施工方面做了些实际工作,积累了一些经验,并形成了对于一些问题的看法.水泵节能原理变频调速系统之所以得到推广,一个很重要的原因就是它有较好的节能效果.一台水泵的实际扬程与电源频率的平方成正比.因而通过变频器改变水泵电机的供电频率,就可控制水泵的供水压力.恒压供水自动控制变频恒压供水原理框图如图1所示. 为给定的压力值, 为压力传感器从管道上所测得的实际压力值,PID调节器通过对两者的误差运算,并经过控制变频器的频率输出,从而使管道的压力始终保持在设定值上。该系统能自动检测用户的瞬时水压,据此调节给水量的多少及电机的运行状况.还可根据所需的给水压力设定控制压力值,让设备始终处于恒压状态,从负载电机的特性可知,所配电机的轴功率与其转速的三次方成正比,即 .例如,当变频器输出频率为35Hz(最高设定为50Hz),也就是实际转速为额定转速的70%时,调速器的用电量为0.343,约占额定的35%.也就是说,水泵总处于恒压变流量匹配方式的工作状态,从而消除了超压和回流的无功损耗.恒速与变频调速轴功率变化曲线如图2所示,比较可知,变频调速方式节能效果最为明显。二、实例分析：恒压供水是通过变频调速来调节水的流量从而达到恒压的目的,它最终控制的目标是水压.控制对象具有非线性、滞后特性.PID调节器性能的好坏,在很大程度上决定了恒压供水的质量.当系统在启动与停止阶段,或压力设定值大幅度变化时,由于在短时间内存在很大的偏差,因而无论PID调节器的控制算法采用增量式还是位置式,其积分项将取蓄水池、水泵组(1M,2M)及相关辅配件构成.本系统的核心是变频调速控制柜,它通过压力传感器对管网压力进行实时监测,并转换为电信号提供给变频器进行运算,通过变频器、可编程控制器PLC与继电器阵列的共同控制,构成了完善的全自动变频调速给水系统。变频器的品种繁多,如三菱、富士、三肯及ABB等型号.一般常选用泵类、风机专用系列.以三菱FR-A140E为例,它除了一般品牌所具有的功能外,还有如下特点:内部采用IPM智能功率模块,使电机的噪音减至最低;变频器与工频电源之间可进行切换,用户只需通过PLC输入启动、停止及自动切换指令,就可方便地通过接触器的互锁动作来切换不同的水泵,而不需要像以往那样自行设计繁

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