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1、<p><b>  外文翻譯</b></p><p><b>  譯文:</b></p><p> ?。校蹋谩。裕澹恚穑澹颍幔簦酰颍濉。茫铮睿簦颍铮臁。铮妗。幔睢。牛欤澹悖簦颍椋恪。龋澹幔簦椋睿纭。疲酰颍睿幔悖濉?lt;/p><p> ?。粒猓螅簦颍幔悖簦海裕瑁椋蟆。穑幔穑澹颉。椋睿簦颍铮洌酰悖澹蟆。帷。簦澹恚穑澹颍?/p>

2、ture?。悖铮睿簦颍铮臁。螅螅簦澹怼。妫铮颉。妫椋睢。澹欤澹悖簦颍椋恪。瑁澹幔簦椋睿纭。妫酰恚幔悖濉。猓幔螅澹洹。铮睢。簦瑁濉。校蹋谩。簦澹悖瑁睿铮欤铮纾。幔睿洹。簦瑁濉。澹欤澹悖簦颍铮睿椋恪。颍澹悖簦椋妫椋澹颉。簦澹悖瑁睿铮欤铮纾裕瑁濉。瑁幔颍洌鳎幔颍濉。幔睿洹。螅铮妫簦鳎幔颍濉。铮妗。簦瑁濉。螅螅簦澹怼。幔颍濉。幔欤螅铩。铮酰簦欤椋睿澹洌?lt;/p><p> ?。耍澹鳎铮颍洌海穑颍铮纾颍幔恚恚?/p>

3、ble?。欤铮纾椋恪。悖铮睿簦颍铮欤欤澹?;heating?。妫酰颍睿幔悖澹唬校桑?lt;/p><p>  1 Introduction</p><p>  Hot stove using simple bit type constant temperature control method, temperature control precision is not high, the temp

4、erature control is of unidirectional rising, large inertia, large time delay, time-varying characteristics, and the heating, thermal insulation is dependent on the resistance wire heating, cooling, rely on the natural en

5、vironment for cooling or add furnace material, once the overshoot is difficult to use control means to bring the temperature. According to mathematical model of</p><p>  2 System structure</p><p&g

6、t;  . The hardware device is mainly composed of PC, programmable controller, temperature sensor, temperature transmitter, solid state relays and electric heating furnace. As shown in figure 1.</p><p>  Fig 1

7、 the block diagram of the control system of heating furnace</p><p>  The control system of control information and data information in the computer centralized management, allocation, make the system more si

8、mple, effective, the user can browse, printing various field data, statements, and also to control the spot operation control. The temperature control system of single loop control system, by the Mitsubishi Co Fx2N serie

9、s PLC as the core component, temperature detection using platinum thermal resistance KrlOO, used for real-time detection of temperature output</p><p>  3 PID control algorithm to achieve the PLC</p>&

10、lt;p>  Using programmable controller for analog PID control, you can use the PID process control module, and this module is expensive, economy is poor. The system uses the PID function instruction, when P1D function i

11、nstruction with the analog quantity when used together, not only can be similar to the PID process control module, and the economy is good. Due to the heating furnace is large delay, large inertia link control object, th

12、e system adopts the integral separation PID algorithm and Bang positio</p><p>  PLC main program flow diagram as shown in figure 2,</p><p><b>  Fig 2</b></p><p>  The PI

13、D algorithm program flow diagram as shown in Figure 3</p><p><b>  Fig 3</b></p><p>  4 PID algorithm for converting the PWM wave output</p><p>  The adjustment of the te

14、mperature control is the control of the bidirectional thyristor turn-on time, thereby changing the heating wire heating power to realize the temperature control. First of all, the PID operation result is converted into a

15、n internal timer timing value, to determine the delay time. This system adopts the power regulating circuit, control a power cycle in the actual conduction time, the output MV is converted to a time value mode. Due to th

16、e use of an internal timer time base</p><p>  5 conclusions</p><p>  In the control system of the furnace, the PLC is called when the built-in PID calculation program, realized PID control algor

17、ithm based on call, simplify program, improve the programming efficiency, and is not easy to make a mistake, the temperature reached the goal of accurate control; at the same time, by the PID operation result decided wid

18、th, with the timer generated PWM wave, switch quantity instead of analog output, realize the PWM wave output, allows the system to control cost. Proved by </p><p>  Change the heating wire heating power to r

19、ealize the temperature control. First of all, the PID operation result is converted into an internal timer timing value, to determine the delay time. This system adopts the power regulating circuit, control a power cycle

20、 in the actual conduction time, need to be output</p><p>  MV is converted to a time value mode. Due to the use of an internal timer</p><p>  T200, time is 10 ms, because the power cycle selecte

21、d for Tz, so real</p><p>  During heating time for t:fⅢ100Tz detector, the time value is stored in the database</p><p>  Register D, for timer instruction calls. In PLC, there are two ways to ge

22、nerate PwM output pulse wave, one is by the PLC PWM special instruction generated, but PWM wave output channels is limited, such as the FXzN series PLC only Y0 and Y1 two channels; another is the internal timer to organi

23、zation, the switch quantity channel output. The system uses second methods, by two timer T200 and T246 produce a PWM wave, T246 decided to transfer power cycle, in order to ensure the normal conduction of th</p>&

24、lt;p><b>  Reference</b></p><p>  ( 1 ) Chen Yuanqi, .F%N programmable controller for temperature monitoring and control system</p><p>  Design LJq. micro computer information, 200

25、5, ( 15).</p><p>  ( 2 ) the clock Zhaoxin . The programmable control theory and application EM . Guangzhou SCUT;</p><p>  University Press, .2003 ( 11).</p><p>  ( 3 ) Song Bosheng

26、.PLC programming and practical guide ( M ) . Beijing : mechanical industry</p><p>  Press .2006 ( 6).</p><p><b>  原文</b></p><p>  PLC在加熱爐溫控制系統(tǒng)中的應(yīng)用</p><p>&l

27、t;b>  分享到 </b></p><p><b>  翻譯結(jié)果重試</b></p><p>  抱歉,系統(tǒng)響應(yīng)超時(shí),請(qǐng)稍后再試</p><p>  支持中英、中日在線互譯</p><p>  支持網(wǎng)頁(yè)翻譯,在輸入框輸入網(wǎng)頁(yè)地址即可</p><p>  提供一鍵清空、復(fù)制功能、

28、支持雙語(yǔ)對(duì)照查看,使您體驗(yàn)更加流暢</p><p>  摘要:本文介紹了以三菱plc為核心的加熱爐溫測(cè)量與,重點(diǎn)給出了PID控制算法和參數(shù)整定以及在PLC中的實(shí)現(xiàn)。控制系統(tǒng)系統(tǒng)控制核心單元PLC根據(jù)設(shè)定的溫度值與反饋信號(hào)進(jìn)行分析、運(yùn)算,按照P1D控制算法計(jì)算出控制量,由定時(shí)器生成PWM波,調(diào)節(jié)晶閘管的導(dǎo)通角a,從而實(shí)現(xiàn)溫度的精確控制。</p><p>  關(guān)鍵詞:PLC;PID;控制;溫度

29、;PWM波</p><p><b>  1引言</b></p><p>  熱爐多采用簡(jiǎn)單位式恒溫控制方式,溫控精度不高,由于溫度控制具有升溫單向性、大慣性、大滯后、時(shí)變性等特點(diǎn),而且其升溫、保溫是依靠電阻絲加熱,降溫則是依靠環(huán)境自然冷卻或添加爐料,一旦超調(diào)很難用控制手段使其降溫。針對(duì)被控對(duì)象難以精確確定數(shù)學(xué)模型這一特點(diǎn),本系統(tǒng)由PLC作為核心控制器,根據(jù)溫度的變化采

30、用PID控制器,對(duì)溫度的采集數(shù)據(jù)進(jìn)行計(jì)算,然后通過(guò)PLC輸出控制量,調(diào)節(jié)晶閘管的導(dǎo)通,達(dá)到溫度的精確控制。本文的控制對(duì)象為常用于冶金行業(yè)的HX-1型電加熱爐,爐溫為20-600°。</p><p><b>  2系統(tǒng)構(gòu)成 </b></p><p>  硬件設(shè)備主要由上位機(jī)、可編程控制器、測(cè)溫元件、溫度變送器、固態(tài)繼電器及電加熱爐組成。如圖1所示。</p

31、><p>  圖1加熱爐控制系統(tǒng)框圖</p><p>  控制系統(tǒng)的各種控制信息和數(shù)據(jù)信息都在上位機(jī) 集中管理、分配,使系統(tǒng)維護(hù)更加簡(jiǎn)單、有效,用戶不但 可以瀏覽、打印現(xiàn)場(chǎng)的各種數(shù)據(jù)、報(bào)表,同時(shí)還能夠?qū)?控制現(xiàn)場(chǎng)的運(yùn)行情況進(jìn)行控制。 此溫度控制系統(tǒng)屬于單回路閉環(huán)控制系統(tǒng),以三 菱公司Fx2N系列PLC為核心部件,溫度檢測(cè)采用鉑熱 電阻KrlOO,用來(lái)實(shí)時(shí)檢測(cè)溫度輸出,經(jīng)RTD模塊放 大后送入模

32、擬量輸入模塊Fx2N一4AD,轉(zhuǎn)換成數(shù)字 量,經(jīng)用戶程序處理后,調(diào)用PLC內(nèi)部PID控制算法, 得到一個(gè)PID運(yùn)算值,將該值變換為時(shí)間值,以一個(gè)隨 時(shí)間變化的PWM波來(lái)控制電壓過(guò)零觸發(fā)的固態(tài)繼電 器SSR,以調(diào)節(jié)電加熱絲的工作電流,實(shí)現(xiàn)加熱爐系統(tǒng) 的溫度控制。 軟件部分以Windows XP為操作系統(tǒng),采用工控 組態(tài)軟件MCGS為應(yīng)用服務(wù)器平臺(tái)。上位機(jī)與PLC 之間通過(guò)MPI口連接,實(shí)現(xiàn)上位機(jī)與PLC之間的通 訊。由上位機(jī)完成對(duì)溫度設(shè)定

33、、實(shí)時(shí)溫度及各控制參 數(shù)的實(shí)時(shí)監(jiān)控。</p><p> ?。常校桑目刂扑惴ǖ模校蹋脤?shí)現(xiàn)</p><p>  用可編程控制器對(duì)模擬量實(shí)現(xiàn)PID控制時(shí),可以使用PID過(guò)程控制模塊,但此模塊價(jià)格昂貴,經(jīng)濟(jì)性差。本系統(tǒng)使用PID功能指令,當(dāng)P1D功能指令與模擬量一起使用時(shí),不但可以得到類似于PID過(guò)程控制模塊的效果,而且經(jīng)濟(jì)性好。由于加熱爐是大滯后、大慣性環(huán)節(jié)控制對(duì)象,本系統(tǒng)采用了積分分離的位置式

34、PID算法與Bang-Bang控制相結(jié)合的方法,即在過(guò)程的開(kāi)始、結(jié)柬或大幅增加設(shè)定值時(shí),采用Bang-Bang控制,防止偏差過(guò)大,產(chǎn)生積分積累,引起系統(tǒng)較大的超調(diào)甚至振蕩,使系統(tǒng)的穩(wěn)定性下降。而到過(guò)程后期,當(dāng)偏差達(dá)到規(guī)定的范圍內(nèi)時(shí),增加積分作用,以提高控制精度。在實(shí)際調(diào)試過(guò)程中,經(jīng)過(guò)幾次修改控制參數(shù),即可取得良好的控制器參數(shù),達(dá)到要求的精度。</p><p> ?。校蹋弥鞒绦蛄鞒虉D如圖2所示,</p>

35、;<p>  PID算法程序流程圖如圖3所示</p><p>  4 PID算法轉(zhuǎn)換為PWM波輸出</p><p>  調(diào)工控溫就是控制雙向晶閘管的導(dǎo)通時(shí)間,從而改變加熱絲的加熱功率來(lái)實(shí)現(xiàn)溫度的控制。首先,將PID運(yùn)算結(jié)果轉(zhuǎn)換成一個(gè)內(nèi)部定時(shí)器的計(jì)時(shí)值,以確定延時(shí)時(shí)間。本系統(tǒng)采用的是調(diào)功電路,控制一個(gè)調(diào)功周期中的實(shí)際導(dǎo)通時(shí)間,需將輸出量MV轉(zhuǎn)換為時(shí)間值的方式。由于使用內(nèi)部定時(shí)器

36、T200,時(shí)基為10ms,又由于調(diào)功周期選為Tz,所以實(shí)際加熱時(shí)間為t:f一Ⅲ儀100Tz,將時(shí)間值存放在數(shù)據(jù)寄存器D中,供定時(shí)器指令調(diào)用。在PLC中,有兩種方式產(chǎn)生PwM輸出脈沖波,一種是由PLC的PWM專用指令產(chǎn)生,但PWM波輸出通道有限,如FXzN系列PLC僅有Y0和Y1兩個(gè)通道;另一種是用內(nèi)部定時(shí)器來(lái)組織,經(jīng)開(kāi)關(guān)量通道輸出。本系統(tǒng)采用第二種方法,由兩個(gè)定時(shí)器T200和T246產(chǎn)生一路PWM波,T246決定調(diào)功周期,為保證晶閘管的

37、正常導(dǎo)通,確保主電路正常工作,PLC輸出的脈沖必須與電網(wǎng)頻率保持嚴(yán)格的同步關(guān)系,為此,將與電網(wǎng)電源同步并保持倍頻關(guān)系的基本數(shù)字脈沖送入PLC輸入端,作為定時(shí)器T246的邏輯控制信號(hào),T200決定脈沖寬度,延遲時(shí)間t由PID運(yùn)算的輸出值MV決定。</p><p> ?。到Y(jié)論在該加熱爐控制系統(tǒng)中,采用分時(shí)調(diào)用PLC內(nèi)置的 PID運(yùn)算程序,實(shí)現(xiàn)了PID控制算法的調(diào)用,簡(jiǎn)化了程序, 提高了編程效率,而且不易出錯(cuò),達(dá)到了

38、溫度精確控制的 目的;同時(shí),由PID運(yùn)算結(jié)果決定脈寬,用定時(shí)器產(chǎn)生 PWM波,用開(kāi)關(guān)量代替模擬量輸出,實(shí)現(xiàn)了PWM波的 多路輸出,使得系統(tǒng)控制成本降低。實(shí)踐證明,該系同具 有動(dòng)態(tài)響應(yīng)快,控制精度高,具有很強(qiáng)的魯棒性的特點(diǎn)。改變加熱絲的加熱功率來(lái)實(shí)現(xiàn)溫度的控制。 首先,將PID運(yùn)算結(jié)果轉(zhuǎn)換成一個(gè)內(nèi)部定時(shí)器的 計(jì)時(shí)值,以確定延時(shí)時(shí)間。本系統(tǒng)采用的是調(diào)功電路, 控制一個(gè)調(diào)功周期中的實(shí)際導(dǎo)通時(shí)間,需將輸出量MV轉(zhuǎn)換為時(shí)間值的方式。由于使用內(nèi)

39、部定時(shí)器T200,時(shí)基為10 ms,又由于調(diào)功周期選為Tz,所以實(shí)際加熱時(shí)間為t:f一Ⅲ儀100Tz,將時(shí)間值存放在數(shù)據(jù)寄存器D中,供定時(shí)器指令調(diào)用。 在PLC中,有兩種方式產(chǎn)生PwM輸出脈沖波, 一種是由PLC的PWM專用指令產(chǎn)生,但PWM波輸出通道有限,如FXzN系列PLC僅有Y0和Y1兩個(gè)通 道;另一種是用內(nèi)部定時(shí)器來(lái)組織,經(jīng)開(kāi)關(guān)量通道輸 出。本系統(tǒng)采用第二種方法,由兩個(gè)定時(shí)器T200和 T24</p><

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