外文翻译--基于PLC和组态软件的冷水供应自动控制系统的发展（适用于毕业论文外文翻译+中..doc

1、译文及原稿译文题目：基于PLC和组态软件的冷水供应自动控制系统的发展原稿题目：Development of Automatic Control System for Supplying Cold Water Based on PLC and Configuration Software基于PLC和组态软件的冷水供应自动控制系统的发展摘要：为了给实验室的发动机供应冷水，本文采用PLC，组态软件，人机界面，变频器构造一个自动控制系统。这个系统是一个分布式控制系统，具有较高的可靠性和可维护性。利用网络读取和写入解决多个设备之间的沟通问题。远程监控软件使用组态软件。通过测量管道的入口和出口，实时调整制

2、冷设备的温度和水泵的压力，以保证供应稳定冷水温度和压力。因此，供水质量得到了改善，节约了大量的电能。实践证明，这个系统的设计，满足用户的需求。该系统具有良好的可靠性和较高的自动化程度。关键词：PLC，组态软件，供水，自动控制系统1.介绍随着科技的发展，电子控制技术已广泛应用于各种领域。PLC（可编程逻辑控制器）作为一个新的发明，迅速改变了电力控制技术的面貌，尤其是在工业控制领域1。随着计算机网络的发展，组态软件的开发，使得分布式控制系统和计算机技术的步伐的日趋成熟，简化了不同设备之间相互联系的过程，提高了项目自动化的效率和节省维护和升级的成本。本文介绍了基于PLC（由西门子公司生产的S7-20

3、0系列）和组态软件（由北京亚控科技发展有限公司开发的“组态王”）在一汽技术中心实验室发动机的（第一汽车工作组公司）供应冷水自动控制系统。它已成功地根据设施水的消耗自动供应冷水和智能调整功率。另一个特点是，该系统可确保在一个恒定的温度和压力条件下的供水，这意味着冷冻水到每一个供水站，并在5分钟内各种温度梯度转移是小于1C和压力为3 -4bar时供应冷水的精度为61C。2. 系统进程简介供应冷水的设施是位于技术中心的院子里的水泵房，布局如图1所示。实验室发动机所产生的高温废水通过房子里的管道和泵回流（图1左边的管道）。然后水通过净化设施清理，然后通过固定频率泵送到制冷设备冷却；接着，冷冻水通过二次

4、变频泵被送到所要供水的端口（图2右管道）；最后，它提供给实验室发动机。在这里水是循环使用的，以达到节约资源的目的。该系统有六个功能：控制五个单位的固定频率泵，控制四个单位的二次变频泵，控制恒压单位和相应的电动阀门，监测和控制水温，监测水冷却设备的运行状况，以及整个供水系统的集中控制。恒压装置水箱净水器图1供应冷水设施布局。3. 硬件设计A.控制系统的网络结构该系统是分布式控制系统如图2所示。这是由中央控制计算机（上位机），（下位机PLC），触摸屏，通信网络和组态软件软件构成。该框架具有较高的可靠性和可维护性。由中央控制计算机协调整个系统的正常运行。其主要任务包括监控系统的运行状况，下位机PLC

5、运行参数设置和修改，监控水冷却单位运行状况和其参数的制定和修改和实施系统数据库的运行状态和远程监控功能。四个PLC模块（下位机控制）根据中央控制计算机控制工作，从而保证输出的冷冻水的温度和压力，在规定的范围内改变。三个水冷却设施的PLC模块自动控制水冷却电动机的运行。在系统集成控制柜中的PLC模块，实现实时收集参数和通过中央控制计算机通讯来控制下位机，同时与三套水冷却单位的PLC模块进行通信，监控运行参数，并根据系统的要求控制水冷却单位。触摸屏为用户提供了手动操作，调整，维护界面。下位机的监测和控制包括一个冷冻水机组（CW390），2套水冷却单位（CW840），2套逆变器，5套固定频率泵（15

6、KW），4台变频泵（22KW），2台水冷冻泵，1套净水器，1套恒压装置，18套电动蝶阀。实时显示的参数，包括水的输出和输入的温度和压力，供水流量，冷冻水循环亚系统的供水和回水温度，双变频泵和冷冻水水泵的运行频率，以上这些参数都是由传感器和逆变器反馈。冷冻水电器控制柜远程监测和控制计算机 0西门子1#机组控制柜PLCCPU224XP触摸屏1#机组控制柜PLCCPU224XP触摸屏1#机组控制柜PLCCPU224XP触摸屏1#机组控制柜PLCCPU224XP触摸屏RS232RS485多点接口电缆冷冻水电器控制柜3452图2 控制系统的网络结构中央控制计算机的在网络地址是0，其中蕴藏着整个系统自动运

7、行任务和在设施调试过程中使用的计划。人机界面的地址为1，在系统集成控制柜中的PLC的地址是2，而其他三个控制单位的地址分别为3,4和5。网络配置在STEP 7中进行的，主要包括设置最高的地址，波特率等。最高地址设置为15主要是为了增加在这个系统网络的波特率和波特率被设置在19.2 Kbps。B. PLC配置为了使系统简单，可靠和安全的，按设计要求，选择构建自动控制系统，采用CPU型号为226和西门子S7- 200系列的扩展型号EM223，EM231，EM232，包括一套226的CPU，3套EM223，2套EM231，一套EM232。过程改进是另一个重要的考虑因素。CPU 226: CPU 22

8、6 AC/DC/RLY,使用交流电，由直流数字输入点，继电器数字输出点组成，包括24个输入点，16点输出。它会立即与远程监控计算机通信，并监测当地设施的状态及参数反馈给计算机，它可以接受来自远程监控计算机的指令并执行相应的操作，它可以控制3台冷却水机组，并与他们沟通，它还可以控制其他设施：5套固定频率泵，4台变频泵，18电动阀，2套传感器。它可以采集模拟输入：液压压力，流速和流出及流入水的温度。EM223：数字I / O模型，它有6种类型。在这个项目中，被选为型16点24V直流输入16点继电器输出。EM231：模拟输入模式，4个电流/电压输入通道。EM232：模拟量输出模块，2个电流/电压输出

9、通道。4. PLC程序设计根据西门子STEP7开发PLC梯型程序，通过模块化设计方法，这样，独立的功能打包成块，从而提高程序的可读性和减少迭代部分。A.自我调节供水压力由于实验室发动机所需的数额是不恒定，系统需要自动检测和调节水的压力，没有人为干预，运行后由一个固定频率泵，系统根据入水和回水管道的压力差控制运行频率和变频泵的流量，调整方法，根据不同项目的需要不同而不同，该项目通过频率换算公式为：（1）： (1)其中f是变频器的输出频率，F0是基本频率，Tpv是是瞬间的温差，Tsp是温差设定值，Psp是压力设定值，Ppv是瞬间压力，C1是温差调节系数，C2是压力差调节系数，t是调整期。在变频调速

10、中，在2t时间间隔内对即时温差和即时的压力进行采样。当温差偏离设定值，变频器的输出频率将根据公式（1）调整，当压力低于设定值，变频器的输出频率将根据公式（1）调整。在调节过程中，保证变频器的输出频率在基本频率（40HZ）和逆变器的最大输出频率（50HZ）之间变化。如果公式的计算结果小于基波频率，它会被基本频率替换，相反，由公式计算结果大于变频器的最大输出频率，将被变频器的最大输出频率替换。控制流程如图3所示。B.多个设备之间的程序通信正如图2所示，供水的自动控制系统是基于RS - 485总线的包括两个层面的分布式控制系统，中央控制计算机是整个上层系统的控制中心，下层的控制中心是型号为226的C

11、PU模型。除即时与中央控制计算机完成数据采集和远程控制沟通，它也需要在3台冷冻水机组与PLC通讯，以便于掌握各单位的工作参数和控制。通过网络读取和写入给S7系列PLC提供指令来解决这个问题，NETR指令（网络阅读）是用来初始化通信操作，从远程设备接收数据，通过通信端口，并保存在TBL。 NETW指令（网络写入）是用来初始化通信操作，TBL通过特定的端口写数据到远程设备3。STEP7中提供的说明书，以帮助用户创建NETR及NETW方案，在这个系统中，系统集成控制柜中的PLC需要同3台冷冻水机组读取的各单位的压缩机的能量调节阀的状态，压缩机的油位开关的位置，高压开关和低压开关故障，排气压力传感器，

12、输出水传感器的温度，吸气压力传感器，单位经营状况等进行沟通。在所有14个开关值条件下，在所有开关，阀门开放三通阀开启，启动倒计时参数的数值，也需要设置以下10个数值，包括各单位的启动和关机温度，能量调节，出水温度，吸气和排气压力，系统及旁路阀门的开度，阀门的和下面的3个开关控制：远程或本地的选择，引导带和重新启动的温度。启动启动第一台泵逆变器频率=50HZ持续时间延迟时间增加和减少泵在电源频率下启动第一台泵在转换频率下启动第二台泵频率调整频率调整逆变器频率=40HZ持续时间延迟时间增加和减少泵是保持第二台泵在转动频率下运行停止第一台泵逆变器频率=50HZ持续时间延迟时间增加和减少泵在电源频率下

13、启动第二台泵在转换频率下启动第一台泵频率调整频率调整逆变器频率=40HZ持续时间延迟时间增加和减少泵是保持第一台泵在转动频率下运行停止第二台泵是是图3 供水压力的自我流量调节。5.远程监视和控制软件的设计中央控制计算机通过运行远程监视和控制软件监视和控制系统供应冷却水，主要功能包括：监测现场设备的运行状态，自动提供冷冻水，设备的手动操作和设置运行参数，实时显示运行参数变化曲线，历史数据记录和查询和故障报警。远程监控软件主要是由5个部分组成：系统进程的整体画面（显示在图1），操作画面，参数设定画面，历史趋势画面，和报警记录画面。按下按钮，每个菜单可以自由切换。操作员只需要选择自动检查软件控制的手

14、段，按运行按钮，然后自动控制系统中的所有设施循环供水将启动。正在运行的进程系统可以根据供水的入口和出口的压力和温度，自动切换降低开关设备频率和调整运行频率。远程监控软件由组态软件“组态王”开发。组态王是由北京亚控科技发展有限公司生产的中文配置软件。组态王程序比较容易，使用方便且功能强大，具有较高的性能价格比，使用组态王的这些方案或设施，需要传输的数据与外围设备（下位机），外围设备包括：PLC，仪表，印刷电路板等，他们通常通过串口与上位机的数据传输，组态王只有在确定外围设备后，才可以与他们通过I / O口转移数据变量。我们选择计算机的COM1通过MPI电缆与现场设备通信，就是那些有RS232/4

15、85转换器，并能达到标准RS232和RS485之间的标准设备。通信速率为19.2Kbps之间，数据格式8N1。6.结论为了提高供水质量，保证充足的水量和稳定的压力，使用多台水泵恒压供水的控制系统的应用将越来越普遍，。从而自动控制系统，具有可以供应恒压供水的实用价值，并具有良好的可靠性和的控制性能。虽然，本文所示的自动控制系统是为某些客户的开发，但是有一定程度的推广应用价值。这个系统是在2007年投入使用。在过去3年，一直在稳定运行并具有较高的自动化程度。它使用方便，易于维护，消费者的反响良好。Development of Automatic Control System for Supplyi

16、ng Cold Water Based on PLC and Configuration SoftwareAbstract: In order to supply cold water for engine laboratory PLC, configuration software, HMI, and inverter are adopted to construct an automatic control system in this paper. The control system is a distributed control system, which has higher d

17、ependability and maintainability. The reading and writing network instructions are utilized to solve the communication among multi-master problem. The remote monitoring software is developed with configuration software. By measuring temperature and pressure of entrance and exit pipes, refrigeration

18、equipments and water pumps are adjusted real-time to guarantee to supply stable temperature and pressure cold water. Therefore the quality of water is improved and power is saved. Practice proves that the system designed meets users requirement. The system has a good reliability and high degree of a

19、utomation.Keywords: PLC; configuration software; supply water; automatic control systemI. IntroductionWith the development of technology, the electricity control technology has been widely applied in various fields. As a new invention, PLC (Programmable Logic Controller) is ameliorating the visage o

20、f electricity control technology at a rapid speed, particularly in the field of industry control 1. In pace with the development of computer network, configuration soft-wares, which was produced with the distributed control system and computer techniques getting mature, simplify the process of inter

21、-linkage among different facilities, enhance the efficiency of Automation projects and save the maintenance and upgrade expenditure 2,3. This article introduced an auto control system for supplying cold water for the engine laboratory of technique center in FAW (First Auto Work Group Company) based

22、on the PLC of S7-200 series produced by Siemens company and the configuration software Kingview produced by Peking Well in Tech company. It has succeeded in automatic supplying cold water and intelligent adjusting power of facilities according to water consumption. Another feature is that this syste

23、m ensures the supply of water at a constant temperature and pressure condition. It means that the precision of cold water in exits is 61C when the frozen water is transferred into every water supply station and the variety of temperature gradient within 5 minutes is less than 1C, and the pressure is

24、 3-4bar.II. PROFILE OF SYSTEM PROCESSThe facilities to supply cold water are located at a pump house in the yard of technique center, and the layout can be seen at Fig. 1 below.Figure 1. Layout of facilities to supply cold water.The waste high-temperature water consumed by engine laboratory flows ba

25、ck to pump house via the pipeline (the left pipeline in figure 1). Then the water is purified by clean-up facilities, and refrigerated in refrigeration sets after being drawing out by the fixed frequency pumps; The refrigerated water is drawn to delivery port (the right pipeline in figure 2) by seco

26、ndary frequency conversion pumps. Finally it is supplied to engine laboratory. Water is recycled in order to save water resources. The system has six functions: controlling five units of fixed frequency pumps, controlling four units of secondary frequency conversion pumps, controlling the constant p

27、ressure unit and corresponding electric valves, monitoring and controlling water temperature, monitoring the running condition of water-refrigerated units, and centralized control for whole supply water system.III. DESIGNOF HARDWAREA. Network structure of control systemThe system is a distributed co

28、ntrol system showed Fig.2, which is consisted by central control computer (upper computer), PLC (lower computer), touch screen, communication network and Controlling software. The framework has higher dependability and maintainability. The central control computer coordinates the whole systems norma

29、l running. Its main tasks include supervising the systems running condition, setting and modifying the lower computer operating parameters, surveying water-refrigerated unit running condition and their parameters enactment and modification, and implementing database of system running condition and r

30、emote monitor function. Four PLC modules (lower monitor) work under assistance of central control computer, which guarantees output temperature and pressure of refrigerated water to change in a prescriptive range. Three PLC modules in water-refrigerated facilities automatically control water-refrige

31、rated engine units running. The PLC module in system integrated control cabinet achieves in real-time collecting parameters and controlling lower facilities by communication with the central control computer, meanwhile communicate with three sets of water-refrigerated units PLC modules, acquire oper

32、ating parameters of units, and control water-refrigerated sets according to system requirements. The touch screen provides manual operation and adjustment and maintenance interface to consumer. Lower facilities monitored and controlled include a set of water-refrigerated unit(CW390), 2 sets of water

33、-refrigerated units(CW840), 2 sets of inverters, 5 sets of fixed frequency pumps(15KW), 4 sets of frequency conversion pumps(22KW), 2 sets of water-refrigerated pumps, 1 set of water purifier, 1 set of constant pressure unit, 18 sets of electric butterfly valves. The parameters real-time displayed i

34、nclude the temperature and pressure of water output and input, flux of water supply, the temperature of water supply and backwater of refrigerated water circulation sub-system, the running frequencies of dual conversion pumps and water-refrigerated pumps, these parameters above are fed back by senso

35、rs and inverters.The address of central control computer is 0 in the network, which bears the whole system automatic operation task and can be used as program facility during debugging. The address of HMI is 1. The address of the PLC in system integrated control cabinet is 2, while the other three c

36、ontrolling units addresses are set respectively at 3,4, and 5. The configuration of network was done in STEP7, mainly include setting the highest address, BAUD RATE etc. The highest address was set at 15 in order to increase BAUD RATE in this system network and BAUD RATE was set at 19.2 kbps.Figure

37、2. Network structure of control system.B. PLC configurationIn order to make system simple, dependable and safe, the model CPU 226 and extended models EM223,EM231, EM232 in S7-200 series of Siemens, including aset of CPU 226, 3 sets ofEM223 , 2 sets ofEM231 , a set of EM232, were chosen to construct

38、automatic control system according to design requirements. Process improvement was another important consideration.CPU 226: CPU 226 AC/DC/RLY, works by alternating current, direct current digital input points, relay digital output points, 24 input points, 16 output points. It instantly communicates

39、with remote monitoring computer, and delivered local facilities status and parameters to computer. It can accept orders from remote monitoring computer and execute corresponding operations. It can control 3 cooling-water machine units and communicate with them. It can control other facilities: 5 set

40、s of fixed frequency pumps, 4 sets of frequency conversion pumps, 18 motorized valves, 2 sets of transducer. It can acquire analog input: hydraulic pressure, flow rate and temperature of outcome & income water.EM223: digital I/O model, it has 6 types. In this project, the type 16 points 24V DC input

41、/16 points relay output was selected.EM231 : analog input model, 4 electric current/voltage input channels.EM232: analog output module, 2 electric current/voltage output channels.IV. DESIGN OF PLC PROGRAMPLC programs were developed with ladder under the STEP7 of Siemens. The design method of modular

42、ization was adopted. In this way, independent function was packaged into a block, thus the readability of programs was improved, and iterative parts were reduced.A. Self-regulation of supplied water pressure Since the amount needed by engine laboratories is not constant, the system should automatica

43、lly detect and regulate water pressure without anthropogenic intervention. After unsealing one fixed frequency pumps, the system control running frequency and amount of frequency conversion pumps based on pressure difference between income water and backwater pipelines. The adjustment method varies

44、according to different projects need. This project adopted frequency conversion formula as (1):f=f0+(Tpv-Tsp)xC1+(Ppv-Psp)xC2 (1)Thereinto f is output frequency of inverter, f0 is fundamental frequency, Tpv is instant temperature difference, Tsp is set value of temperature difference, Psp is set val

45、ue of pressure, Ppv is instant pressure, C1 is temperature difference regulation coefficient, C2 is pressure difference regulation coefficient, t is adjustment period. During frequency conversion adjustment, instant temperature difference and instant pressure are sampled by 2t time interval. When te

46、mperature difference deviates from set value, the output frequency of inverter will be adjusted according to (1).When pressure is lower than set value, the output frequency of inverter will be adjusted according to (1).During regulate process, the output frequency of inverter is guaranteed to change

47、 between fundamental frequency (40HZ) and inverters max output (50HZ). If the calculation results by the formula are smaller than fundamental frequency, it will be replaced by fundamental frequency. Instead the calculation results by formulas is bigger than inverters max output frequency, it will be

48、 replaced by inverters max output frequency. The control flow is illustrated as Fig. 3.Figure 3. Flow of self-regulating of supplied water pressure.B. Program communication between multiple masterAs Fig. 2 illustrated, the automatic control system for supply water is consisted of two levels distributed control system based on RS-485 bus, and central control computer is the control center of the whole upper layer system. The lower control center is the model of CPU 226. Except instant communicating with central cont