外文翻譯-- 基于plc的電梯控制系統(tǒng)的設(shè)計(jì)與應(yīng)用

1、<p><b>　　中文5150字</b></p><p><b>　　畢業(yè)設(shè)計(jì)(論文)</b></p><p>　　外文翻譯（附外文原文）</p><p>　　學(xué) 院： 機(jī)械與控制工程學(xué)院 </p><p>　　課題名稱： 基于PLC的施工 </p>

2、<p>　　升降機(jī)控制系統(tǒng)設(shè)計(jì) </p><p>　　專業(yè)(方向)： 自動(dòng)化（控制） </p><p>　　班 級(jí)： </p><p>　　學(xué) 生： </p><p>　　指導(dǎo)教師：

3、</p><p>　　日 期： </p><p>　　Xiaoling Yang, Qunxiong Zhu, Hong Xu. Design and Practice of an Elevator Control SystemBased on PLC [C/OL]. </p><p>　　http://ieeexplore.

4、ieee.org/xpl/articleDetails.jsp?arnumber=4634822, 2008-08-03/2013-05-01.</p><p>　　基于PLC的電梯控制系統(tǒng)的設(shè)計(jì)與應(yīng)用</p><p>　　楊曉玲1, 2, 朱群雄1, 徐宏1</p><p>　　1 北京化工大學(xué)信息與技術(shù)學(xué)院 中國(guó)北京，郵編100029 </p>&

5、lt;p>　　2 北京聯(lián)合大學(xué)自動(dòng)化學(xué)院 中國(guó)北京,郵編100101 </p><p>　　yxl_lmy@sina.com, zhuqx@mail.buct.edu.cn </p><p><b>　　摘要</b></p><p>　　本文介紹了為一幢居民樓的2個(gè)9層電梯而開發(fā)的電梯控制系統(tǒng)。該控制系統(tǒng)采用PLC作為控制器，并采用基于“

6、最少等候時(shí)間”的并聯(lián)調(diào)度規(guī)則使兩個(gè)電梯運(yùn)行于并行模式。本文還詳細(xì)的給出了該P(yáng)LC控制系統(tǒng)基本結(jié)構(gòu)，控制原理和實(shí)現(xiàn)方法，并展示了該系統(tǒng)核心部分的梯形圖。該系統(tǒng)不僅具有簡(jiǎn)單的外圍電路，運(yùn)行結(jié)果還表明，它增強(qiáng)了電梯的性能和可靠性。</p><p><b>　　1 導(dǎo)言</b></p><p>　　隨著建筑技術(shù)的發(fā)展，大樓變得越來越高，電梯也就成為了高層建筑中垂直運(yùn)輸?shù)闹匾?/p>

7、具，舒適，高效的把乘客送往目的地。因此，電梯控制系統(tǒng)對(duì)于每一個(gè)電梯的平穩(wěn)安全運(yùn)行是至關(guān)重要的。它告訴電梯按什么順序來啟停，何時(shí)開關(guān)電梯門，是否有重大的安全問題。</p><p>　　傳統(tǒng)的電梯電氣控制系統(tǒng)是一種繼電器控制系統(tǒng)，具有電路復(fù)雜，故障率高和可靠性差等缺點(diǎn)，大大影響了電梯的運(yùn)行質(zhì)量。因此，受一家企業(yè)的委托，我們已經(jīng)利用PLC技術(shù)改進(jìn)了居民樓中繼電器控制電梯的電器控制系統(tǒng)。結(jié)果表明，改進(jìn)后的系統(tǒng)運(yùn)行可靠，維

8、護(hù)方便。</p><p>　　本文詳細(xì)介紹了該電梯PLC系統(tǒng)的基本結(jié)構(gòu)，控制原理和實(shí)現(xiàn)方法。 </p><p><b>　　2 系統(tǒng)結(jié)構(gòu)</b></p><p>　　該電梯控制系統(tǒng)的目的是讓電梯響應(yīng)乘客的要求并做出正確的運(yùn)動(dòng)。它主要分為兩個(gè)部分：</p><p>　　2.1 電力驅(qū)動(dòng)系統(tǒng)</p><

9、;p>　　這里，電力驅(qū)動(dòng)系統(tǒng)主要包括：電梯轎廂，牽引電動(dòng)機(jī)，電梯門馬達(dá)，制動(dòng)機(jī)構(gòu)和相關(guān)的開關(guān)電路。</p><p>　　這里，我們采用一種新的LC型交流接觸器代替舊的，并使用PLC的觸點(diǎn)來代替大量的中繼器。而牽引電動(dòng)機(jī)的線路則予以保留。這樣，原來控制柜體積大，噪聲大的缺點(diǎn)就被解決了</p><p>　　2.2 信號(hào)控制系統(tǒng)</p><p>　　電梯的控制信號(hào)大

10、多是由PLC實(shí)現(xiàn)的。輸入信號(hào)有：運(yùn)行模式信號(hào)，操作控制信號(hào)，轎廂指令信號(hào)，廳門呼梯信號(hào)，安全/保護(hù)信號(hào)，梯門打/關(guān)信號(hào)和平整信號(hào)等。電梯系統(tǒng)的所有控制功能都是由PLC程序完成的，例如：登記，顯示，取消轎廂指令和廳門呼梯，判斷電梯位置，選擇電梯的運(yùn)動(dòng)方向和層等。圖1中顯示了電梯的PLC控制系統(tǒng)框圖</p><p>　　圖1 PLC信號(hào)控制系統(tǒng)圖</p><p><b>　　2.3

11、 需求</b></p><p>　　開發(fā)這個(gè)控制系統(tǒng)的目的是去控制一幢居民樓的2個(gè)9層電梯。</p><p>　　對(duì)于每一個(gè)電梯，每一層上都安裝了一個(gè)傳感器。我們能利用這些傳感器去了解電梯轎廂的實(shí)時(shí)位置。電梯轎廂的門是靠門電機(jī)來實(shí)現(xiàn)開啟和閉合的。電梯的門上安裝有2個(gè)傳感器，一個(gè)用于通知控制系統(tǒng)電梯門的位置，另一個(gè)可以在電梯門關(guān)閉的時(shí)候偵測(cè)物體。電梯的上下運(yùn)動(dòng)則是通過牽引電動(dòng)機(jī)來

12、控制的。</p><p>　　除了第一層和最高層之外，每一層都有一對(duì)方向燈指明電梯是在上升還是下降。</p><p>　　每個(gè)樓層，都有一個(gè)7段LED用于顯示電梯轎廂的當(dāng)前位置。</p><p>　　明確基本需求是開發(fā)這個(gè)電梯控制系統(tǒng)的第一步，簡(jiǎn)單來說，這兩個(gè)電梯有以下行為：</p><p>　　1)、一個(gè)電梯單獨(dú)運(yùn)行</p>

13、<p>　　一般來說，電梯有三個(gè)運(yùn)行狀態(tài)：正常模式，火災(zāi)保護(hù)模式和維護(hù)模式。維護(hù)模式具有最高的優(yōu)先級(jí)，只有不在維護(hù)模式時(shí)，其他運(yùn)行模式才能執(zhí)行。其次是火災(zāi)保護(hù)模式，當(dāng)火險(xiǎn)開關(guān)作用時(shí)時(shí)，電梯必須立即回到底層或者基站。而火險(xiǎn)開關(guān)復(fù)位后，電梯就應(yīng)該回到正常運(yùn)行模式。在正常操作模式下，控制系統(tǒng)的基本任務(wù)是指揮每個(gè)電梯上下移動(dòng)，停止啟動(dòng)，打開和關(guān)閉電梯門。但其中也有如下的一些限制因素：</p><p>　　每個(gè)電

14、梯都有一組9個(gè)按鈕放置在轎廂的控制面板上，每一個(gè)對(duì)應(yīng)一層樓。當(dāng)按鈕被按下時(shí)，按鈕就會(huì)發(fā)光并且使電梯向相應(yīng)的樓層運(yùn)動(dòng)，當(dāng)電梯到達(dá)指定樓層之后，按鈕的光芒就會(huì)消失。</p><p>　　除了底層和頂層之外，每個(gè)樓層的控制面板上都有兩個(gè)按鈕。一個(gè)按鈕請(qǐng)求電梯上升，另一個(gè)請(qǐng)求電梯下降。按鈕在按下去的狀態(tài)下會(huì)發(fā)光。當(dāng)電梯來到乘客所在樓層時(shí)，按鈕的發(fā)光消失，然后朝著期望的方向運(yùn)行。</p><p>　

15、　電梯轎廂的控制面板和樓層的控制面板上的按鈕都是用來控制電梯運(yùn)行方向的。</p><p>　　電梯不能漏過任何樓層，如果那個(gè)樓層有乘客想要出去。</p><p>　　電梯不能在沒有乘客要出去的樓層停止</p><p>　　直到將所有當(dāng)前方向的乘客送達(dá)之前，電梯不能改變方向，并且，當(dāng)電梯在相反方向運(yùn)行時(shí)，廳門呼梯不能得到響應(yīng)。</p><p>

16、　　如果電梯沒有接到任何需求，則停在當(dāng)前層，并保持電梯門關(guān)閉。</p><p>　　2)、 兩個(gè)電梯并聯(lián)運(yùn)行</p><p>　　在這種情況下，兩個(gè)電梯同時(shí)為大樓服務(wù)，從早上7點(diǎn)到9點(diǎn)，再?gòu)南挛?點(diǎn)到7點(diǎn)。</p><p>　　當(dāng)電梯到達(dá)某一層，它將測(cè)試是否需要停止，當(dāng)必須停止時(shí)，電梯則會(huì)停在這一層。</p><p>　　與此同時(shí)，為了平衡停

17、止的次數(shù)，兩個(gè)電梯的操作還將遵循一定的調(diào)度原則。</p><p>　　電梯不會(huì)停止在一個(gè)已經(jīng)有另一個(gè)電梯停著的樓層。</p><p>　　正常運(yùn)行模式的電梯是由電力驅(qū)動(dòng)系統(tǒng)和邏輯控制系統(tǒng)共同操控的。</p><p><b>　　3 軟件設(shè)計(jì)</b></p><p>　　由于呼叫時(shí)間，呼叫地點(diǎn)，乘客目的地的隨機(jī)性質(zhì)，電梯控

18、制系統(tǒng)是一個(gè)典型的實(shí)時(shí)，隨機(jī)邏輯控制系統(tǒng)。在這里，我們采用集選控制方法與西門子PLC S7 - 200 CPU226及其擴(kuò)展模塊。系統(tǒng)中有46輸入節(jié)點(diǎn)和46個(gè)輸出節(jié)點(diǎn)。這里I/O節(jié)點(diǎn)詳情見表1和表2 。</p><p><b>　　表1 輸入節(jié)點(diǎn)</b></p><p>　　描述 地址</p>

19、<p>　　1-8 層向上廳門呼梯 I0.0-I0.7 </p><p>　　2-9 層向下廳門呼梯 I1.0-I1.7 </p><p>　　1-9 層轎廂指令 I2.0-I2.7, I3.0 </p><p>　　1-9 抵達(dá)傳感器

20、 I3.1-I3.7, I4.0-I4.1 </p><p>　　電梯門打開按鈕 I4.2 </p><p>　　電梯門關(guān)閉按鈕 I4.3 </p><p>　　電梯門關(guān)閉位置開關(guān) I4.4 </p>&

21、lt;p>　　電梯門打開位置開關(guān) I4.5 </p><p>　　向上調(diào)平傳感器 I4.6 </p><p>　　向下調(diào)平傳感器 I4.7 </p><p>　　火警開關(guān) I5.0 <

22、/p><p>　　驅(qū)動(dòng)器操作開關(guān) I5.1 </p><p>　　電梯門控制面板開關(guān) I5.2 </p><p>　　超載 I5.3 </p><p>　　被迫速度變化開關(guān)

23、 I5.4 </p><p>　　滿載 I5.5 </p><p>　　表2 輸出節(jié)點(diǎn) </p><p>　　描述 地址</p><p>　　1-8 層向上廳門呼梯燈

24、 Q0.0-Q0.7 </p><p>　　2-9 層向下廳門呼梯燈 Q1.0-Q1.7 </p><p>　　1-9 層轎廂指令燈 Q2.0-Q2.7, Q3.0 </p><p>　　向上運(yùn)動(dòng)指示燈 Q3.1 </p>&l

25、t;p>　　向下運(yùn)動(dòng)指示燈 Q3.2 </p><p>　　電梯位置的7段LED顯示器 Q3.3-Q3.7 Q4.0-4.1 </p><p>　　電梯門正在打開 Q4.2 </p><p>　　電梯門正在關(guān)閉

26、 Q4.3 </p><p>　　向上運(yùn)動(dòng) Q4.4 </p><p>　　向下運(yùn)動(dòng) Q4.5 </p><p>　　滿載燈 Q4.6 </p><p>　　高速運(yùn)行

27、 Q4.7 </p><p>　　低速運(yùn)行 Q5.0 </p><p>　　加速 Q5.1 </p><p>　　減速 Q5.2-Q5.4 <

28、/p><p>　　警告發(fā)聲器 Q5.5 </p><p>　　關(guān)于軟件設(shè)計(jì)，我們采用模塊化的方法來寫梯形圖程序。模塊之間的信息傳輸則依靠PLC的中間寄存器來實(shí)現(xiàn)。</p><p>　　整個(gè)程序主要由10個(gè)模塊組成：廳門呼梯登記和顯示模塊，轎廂指令登記和顯示模塊，信號(hào)組合模塊，廳門呼梯取消模塊，電梯位置顯示模塊，樓層選擇

29、模塊，移動(dòng)方向控制模塊，電梯門開啟/關(guān)閉模塊，維護(hù)操作模塊和并行模式下的調(diào)度模塊。</p><p>　　以下是幾個(gè)典型模塊的設(shè)計(jì)描述：</p><p>　　3.1 廳門呼梯登記和顯示模塊</p><p>　　在電梯中有兩種呼叫模式：廳門呼梯和轎廂指令。當(dāng)有人按下樓層控制面板的按鈕，信號(hào)就會(huì)被登記，相應(yīng)的燈就點(diǎn)亮。這就是廳門呼梯登記。當(dāng)乘客按下電梯轎廂內(nèi)的一個(gè)按鈕，信

30、號(hào)將被登記，與之相應(yīng)的燈照亮。這就是轎廂指令登記。圖2顯示了向上廳門呼梯登記和顯示的梯形圖，自鎖原則用來確保呼叫不斷的顯示。</p><p>　　圖2 向上廳門呼梯登記與顯示</p><p><b>　　3.2 呼叫的集選</b></p><p>　　這里使用了集選控制原則。就像圖3中顯示的那樣，M5.1－M5.7，M6.0和M6.1是輔助寄存

31、器。它們分別用來表示從一層到九層的停止請(qǐng)求信號(hào)。輔助繼電器6.2指明電梯驅(qū)動(dòng)器的操作信號(hào)。如果在某一層有一個(gè)呼叫，相應(yīng)樓層的停止信號(hào)將被輸出。當(dāng)電梯被驅(qū)動(dòng)器運(yùn)行時(shí)，廳門呼梯將無法實(shí)現(xiàn)。電梯無法漏過乘客要下車的任何一層。</p><p><b>　　3.3 呼叫取消</b></p><p>　　這個(gè)模塊使電梯能響應(yīng)與轎廂運(yùn)動(dòng)方向相同的廳門呼梯指令，當(dāng)廳門呼梯已經(jīng)得到響應(yīng)

32、，它的登記將被取消。電梯向上廳門呼梯指令取消的梯形圖如圖4。</p><p><b>　　圖3 呼梯的組合</b></p><p>　　圖4 向上呼梯的取消</p><p>　　在圖4中，輔助寄存器M4.0是電梯向上運(yùn)動(dòng)的標(biāo)志，當(dāng)電梯的當(dāng)前運(yùn)動(dòng)是向上，則M4.0的觸電是關(guān)閉的，反之則是打開的。M0.1到M0.7分別對(duì)應(yīng)2樓到8樓的轎廂停止指令。

33、</p><p>　　這個(gè)程序由兩個(gè)功能：</p><p>　　1)、當(dāng)電梯向下運(yùn)動(dòng)時(shí)，使電梯能響應(yīng)正常的向下廳門呼梯指令。當(dāng)指令響應(yīng)之后，則取消該指令的登記</p><p>　　2)、當(dāng)電梯向上運(yùn)動(dòng)時(shí)，相應(yīng)樓層向下的廳門呼梯指令不響應(yīng)并保留指令的登記</p><p>　　向下廳門呼梯的取消則與向上的正好相反。</p><

34、p><b>　　3.4電梯的方向</b></p><p>　　電梯可能向上或者向下運(yùn)動(dòng)，取決于廳門呼梯和轎廂指令，圖5中的梯形圖是電梯向上運(yùn)動(dòng)的情況。</p><p><b>　　圖5 電梯向上運(yùn)動(dòng)</b></p><p>　　圖5表明，當(dāng)呼叫的樓層比當(dāng)前電梯所在樓層高時(shí)，電梯將向上運(yùn)動(dòng)。輔助寄存器M4.0被用作電梯

35、向上運(yùn)動(dòng)的標(biāo)志。當(dāng)電梯向上運(yùn)動(dòng)，向上運(yùn)動(dòng)的指示燈就被點(diǎn)亮。M4.0也就被連接上了。當(dāng)電梯到達(dá)頂層時(shí)，向上運(yùn)動(dòng)的指示燈熄滅，計(jì)時(shí)器開始運(yùn)行。0.2秒之后，M4.0被斷開。向上運(yùn)動(dòng)顯示停止。這里M4.0代替了Q3.1，用來確保取消的可靠性。</p><p>　　3.5 電梯的樓層停止</p><p>　　圖6的是電梯樓層停止功能的梯形圖。</p><p>　　如圖6，M

36、6.4是樓層停止信號(hào)的標(biāo)志，驅(qū)動(dòng)器傳送樓層停止信號(hào)到M6.6，火警開關(guān)傳送火警信號(hào)給M7.0，M6.7顯示速度改變信號(hào)。這些接觸器中的任何一個(gè)工作，樓層停止信號(hào)就會(huì)發(fā)送。</p><p>　　4 最小等待時(shí)間算法</p><p>　　在電梯系統(tǒng)中，通常有兩種控制任務(wù)，一個(gè)是基本的控制功能，用于指揮電梯上下運(yùn)動(dòng)，啟停，電梯門的開合。另一個(gè)則是用來控制一組多個(gè)電梯。</p>&l

37、t;p>　　作用于廳門呼梯和轎廂指令的一組控制系統(tǒng)的最主要的需求應(yīng)該包括：對(duì)大樓的每一層都提供同樣的服務(wù)；最小化乘客等待的時(shí)間；最小化乘客在電梯轎廂內(nèi)的時(shí)間；在規(guī)定時(shí)間內(nèi)為盡可能多的乘客服務(wù)[1]。</p><p>　　圖6 電梯的樓層停止</p><p>　　電梯的組控制有許多種算法，例如最鄰近算法[2]，這種算法下，電梯總是在下一步先響應(yīng)最近的要求；分區(qū)算法[3]通過分析不同樓層

38、的電梯需求情況來調(diào)度電梯；奇偶算法使一個(gè)電梯僅僅為基數(shù)層服務(wù)，而另一個(gè)則只為偶數(shù)層服務(wù)。</p><p>　　最鄰近算法使相鄰的兩個(gè)要求之間電梯的空運(yùn)行最小。從而得到非常小的平均等待時(shí)間。但個(gè)別的等待時(shí)間可能非常長(zhǎng)。分區(qū)算法通常適用于大樓中流量非常大的情況下，例如午餐時(shí)候的辦公室大樓。</p><p>　　相對(duì)于辦公樓和購(gòu)物商場(chǎng)，居民樓的電梯使用人流量是比較小的，而且各層之間人流比較平均。

39、其次，人們通常認(rèn)為電梯就是一種純粹的工具，對(duì)于他們中的大部分人來說乘坐電梯時(shí)間就是在等待。此外，試圖滿足所有需求也是不切合實(shí)際的?；谝陨系脑?，我們采用最小等待時(shí)間的算法來實(shí)現(xiàn)2個(gè)電梯的并行運(yùn)行[4]。</p><p><b>　　4.1 預(yù)估函數(shù)</b></p><p>　　最小等待時(shí)間算法的目的是預(yù)測(cè)每個(gè)電梯對(duì)所有呼叫的響應(yīng)時(shí)間。然后選出響應(yīng)時(shí)間最短的電梯來服務(wù)

40、。</p><p>　　當(dāng)有一個(gè)呼叫需要響應(yīng)時(shí)，系統(tǒng)根據(jù)等式(1),(2)算出每一個(gè)電梯的函數(shù)值。</p><p>　　J(*)=Min[J(1),J(2),…,J(n)] (1)</p><p>　　J(i)=Tr(i)+KTd(i)+KTo(i) i=1,2,...,n (2)&l

41、t;/p><p>　　J(i)是每個(gè)電梯的估算指數(shù)，Tr(i)表明電梯從當(dāng)前層運(yùn)行到最近呼梯的目的地的時(shí)間。To(i)則是電梯停止時(shí)額外的加速和減速的時(shí)間。Td(i)指乘客進(jìn)入和離開電梯平均所花的時(shí)間。K是廳門呼梯和轎廂指令的和。但是廳門呼梯和轎廂指令對(duì)應(yīng)同一樓層，因此只計(jì)算一次。</p><p>　　4.2 最小等待時(shí)間的計(jì)算</p><p>　　在等式2中，K是一個(gè)

42、定值，To 和Td可以通過統(tǒng)計(jì)的方法獲得。Tr = T*L，T表示電梯經(jīng)過一個(gè)樓層的平均時(shí)間，L表示從當(dāng)前樓層到廳門呼梯樓層之間的樓層數(shù)。</p><p>　　為了計(jì)算L的值，我們假設(shè)兩個(gè)電梯分別為A和B。YA,YB分別表示電梯A和B的當(dāng)前層。當(dāng)廳門呼梯鍵按下，H是一個(gè)相應(yīng)的關(guān)鍵值。H=廳門呼梯所在層的層數(shù)。</p><p>　　我們?yōu)镻LC的實(shí)現(xiàn)定義四個(gè)表：向上廳門呼梯登記表，向下廳門呼

43、梯登記表，轎廂指令登記表A和B，當(dāng)某個(gè)呼叫按鈕被按下時(shí)，樓層值被記錄在相應(yīng)的表單中。</p><p>　　以電梯A為例，定義變量MA, MB 和 MW。MA和MB分別代表電梯A或B相同運(yùn)動(dòng)方向的轎廂指令的極值。</p><p>　　當(dāng)電梯A向上運(yùn)動(dòng)，使MA等于轎廂指令登記表A的最大值，當(dāng)電梯A向下運(yùn)動(dòng)時(shí)，設(shè)MA為轎廂指令登記表A的最小值。</p><p>　　MW代

44、表與A方向相同的廳門呼梯的極值。</p><p>　　當(dāng)電梯A向上運(yùn)動(dòng)，并且向上的廳門呼梯值大于等于YA，則MW置0，否則，MW等于向上的廳門呼梯登記表A中的最小值。當(dāng)電梯A向下運(yùn)動(dòng)，并且向上的廳門呼梯值小于等于YA，MW置0，否則，MW的值等于向下廳門呼梯登記表A中的最大值。</p><p>　　這樣，我們就能根據(jù)YA，H，MA和MW來確定L的值了，總共分為三種情況：1)、當(dāng)廳門呼梯的方

45、向與電梯A運(yùn)動(dòng)方向相反時(shí)：</p><p>　　L=|YA-MA|+|MA-H| (3)</p><p>　　2)、當(dāng)廳門呼梯的方向與電梯A運(yùn)動(dòng)方向相同，并且廳門呼梯先于電梯A發(fā)出指令：</p><p>　　L=|YA-H| (4)<

46、/p><p>　　3)、當(dāng)廳門呼梯的方向與電梯A運(yùn)動(dòng)方向相同，并且電梯A先向該方向運(yùn)動(dòng)：</p><p>　　L=|YA-MA |+|MA-MW|+|H-MW| (5)</p><p>　　這樣，第i層樓的最小等待時(shí)間就能按照等式6來計(jì)算了：</p><p>　　Time(i)=TL(i)+KTd(i)+KT

47、o(i) i=1,2,...,n (6)</p><p>　　當(dāng)電梯運(yùn)行時(shí)呼叫改變，系統(tǒng)會(huì)計(jì)算每個(gè)電梯的最小等待時(shí)間，然后分配當(dāng)前的呼叫請(qǐng)求到那個(gè)擁有較小值的電梯，如果每個(gè)電梯擁有相同的值，則優(yōu)先分配給A。</p><p>　　當(dāng)有一個(gè)電梯發(fā)生故障或者不能服務(wù)時(shí)，系統(tǒng)將會(huì)跳出調(diào)度算法，而進(jìn)入單一運(yùn)行模式。</p><p><b>　　

48、4.3 算法的實(shí)現(xiàn)</b></p><p>　　與單一電梯的運(yùn)行模式相比，并行運(yùn)行模式的區(qū)別主要在于對(duì)廳門呼梯的處理方法。前者使用集選控制方法，后者使用調(diào)度原則與集選控制方法相結(jié)合的方式。</p><p>　　這個(gè)系統(tǒng)要控制一幢九層大樓，所以我們選擇兩個(gè)Siemens S7-200 PLC(CPU226)以及它的擴(kuò)展模塊去分別控制一個(gè)電梯，并使用PPI協(xié)議來實(shí)現(xiàn)兩個(gè)PLC之間的

49、交流。</p><p>　　PPI協(xié)議采用主從交流模式，所以我們將A電梯定義為主電梯，B電梯為從電梯。通過交流程序，兩個(gè)PLC能夠交換信息：例如當(dāng)前位置，廳門呼梯還是轎廂指令，運(yùn)動(dòng)方向等等。然后使用最小等待時(shí)間算法，使兩部電梯的運(yùn)行得到優(yōu)化。</p><p>　　圖7為A電梯轎廂指令極值計(jì)算的梯形圖</p><p>　　在圖7中，VB121～VB130是電梯A每一層

50、轎廂呼叫的寄存器地址。Q3.1是電梯向上運(yùn)動(dòng)的指示燈。轎廂指令的極值保存在VB120中。</p><p>　　圖7 電梯A的轎廂指令最大值計(jì)算</p><p><b>　　5 結(jié)論</b></p><p>　　這篇文章中，我們已經(jīng)通過使用PLC來改進(jìn)了一個(gè)舊的電梯控制系統(tǒng)，并且實(shí)現(xiàn)了兩個(gè)電梯的組控制。新的控制系統(tǒng)已經(jīng)使用一年，它的操作方案如下：

51、</p><p><b>　　1)、低峰時(shí)</b></p><p>　　從早上7點(diǎn)到9點(diǎn)，這時(shí)關(guān)心人們離開大樓</p><p><b>　　2)、高峰時(shí)</b></p><p>　　從下午5點(diǎn)到7點(diǎn)，這時(shí)關(guān)心人們進(jìn)入大樓</p><p><b>　　3)、其他<

52、;/b></p><p>　　從早上6點(diǎn)到晚上12點(diǎn)的所有時(shí)間，除了上述兩段時(shí)間外，這些時(shí)候僅有一部電梯運(yùn)行。</p><p>　　由于改進(jìn)之前系統(tǒng)并非并行模式，因此在高峰期和低谷期的平均等待時(shí)間和最大等待時(shí)間都長(zhǎng)于改進(jìn)后的系統(tǒng)。實(shí)踐結(jié)果表明，改進(jìn)后的系統(tǒng)表現(xiàn)好于改進(jìn)之前。</p><p><b>　　參考文獻(xiàn)</b></p>

53、<p>　　[1] Ricardo Gudwin, Fernando Gomide, Marcio. A Fuzzy Elevator Group Controller With Linear Context Adaptation[M]. IEEE World Congress on Computational Intelligence, 2006.</p><p>　　[2] Philipp Fr

54、iese, Jorg Rambau. Online-optimization of multi-elevator transport systems with reoptimization algorithms based on set-partitioning models[M]. Discrete Applied Mathematics, 2005. </p><p>　　[3] Zheng Yanjun,

55、Zhang Huiqiao, Ye Qingtai, Zhu Changming. The Research on Elevator Dynamic Zoning Algorithm and It's Genetic Evolution[M]. Computer Engineering and Applications, 2008. </p><p>　　[4] Xiaodong Zhu, Qingsha

56、n Zeng. A Elevator Group Control Algorithm for Minimum Waiting Time Based On PLC[M]. Journal of Hoisting and Conveying Machiner, 2001.</p><p>　　Design and Practice of an Elevator Control System Based on PLC&

57、lt;/p><p>　　Xiaoling Yang1, 2, Qunxiong Zhu1, Hong Xu1</p><p>　　1 College of Information Science &Technology,</p><p>　　Beijing University of Chemical Technology, Beijing 100029, Ch

58、ina</p><p>　　2 Automation College of Beijing Union University,Beijing,100101, China</p><p>　　yxl_lmy@ sina.com, zhuqx@mail.buct.edu.cn, </p><p><b>　　Abstract</b></p&g

59、t;<p>　　This paper describes the development of 2 nine-storey elevators control system for a residential building. The control system adopts PLC as controller, and uses a parallel connection dispatching rule based

60、 on "minimum waiting time" to run 2 elevators in parallel mode. The paper gives the basic structure, control principle and realization method of the PLC control system in detail. It also presents the ladder dia

61、gram of the key aspects of the system. The system has simple peripheral circuit and t</p><p>　　Introduction</p><p>　　With the development of architecture technology, the building is taller and t

62、aller and elevators become important vertical transportation vehicles in high-rise buildings. They are responsible to transport passengers, living, working or visiting in the building, comfortable and efficiently to thei

63、r destinations. So the elevator control system is essential in the smooth and safe operation of each elevator. It tells the elevator in what order to stop at floors, when to open or close the door and if</p><p

64、>　　The traditional electrical control system of elevators is a relay-controlled system. It has the disadvantages such as complicated circuits, high fault ratio and poor dependability; and greatly affects the elevator’

65、s running quality. Therefore, entrusted by an enterprise, we have improved electrical control system of a relay-controlledelevator in a residential building by using PLC. The result showed that the reformed system is rel

66、iable in operation and easy for maintenance. </p><p>　　This paper introduces the basic structure, control principle and realization method of the elevator PLC control system in detail.</p><p>　　

67、System structure</p><p>　　The purpose of the elevator control system is to manage movement of an elevator in response to user’s requests. It is mainly composed of 2 parts:</p><p>　　2.1 Electric

68、power driving system</p><p>　　The electric power driving system includes: the elevator car, the traction motor, door motor, brake mechanism and relevant switch circuits.</p><p>　　Here we adopted

69、 a new type of LC series AC contactors to replace the old ones, and used PLC’s contacts to substitute the plenty of intermediate relays. The circuits of traction motor are reserved. Thus the original control cabinet’s di

70、sadvantages, such as big volume and high noise are overcome efficiently.</p><p>　　2.2 Signal control system</p><p>　　The elevator’s control signals are mostly realized by PLC. The input signals

71、 are: operation modes, operation control signals, car-calls, hall-calls, safety/protect signals, door open/close signal and leveling signal, etc. All control functions of the elevator system are realized by PLC program,

72、such as registration, display and elimination of hall-calls or car-calls, position judgment of elevator car, choose layer and direction selection of the elevator, etc. The PLC signal control system diagra</p><

73、p>　　Figure 1 PLC signal control system diagram</p><p>　　2.3 Requirements</p><p>　　The goal of the development of the control system is to control 2 elevators in a 9-storey residential buildin

74、g.</p><p>　　For each elevator, there is a sensor located at every floor. We can use these sensors to locate the current position of the elevator car. The elevator car door can be opened and closed by a door

75、motor. There are 2 sensors on the door that can inform the control system about the door’s position. There is another sensor on the door can detect objects when the door is closing. The elevator car’s up or down movement

76、 is controlled by a traction motor.</p><p>　　Every floor, except the first and the top floor, has a pair of direction lamps indicating that the elevator is moving up or down.</p><p>　　Every floo

77、r, has a seven segment LED to display the current location of the elevator car.</p><p>　　The first step for the development of the elevator control is to define the basic requirements. Informally, the elevat

78、ors behavior is defined as follows.</p><p>　　(1)Running with a single elevator</p><p>　　Generally, an elevator has three operation states: normal mode, fire-protection mode and maintenance mode.

79、 The maintenance mode has the highest priority. Only the maintenance mode is canceled can the other operation modes be implemented. The next is fire-protection mode, the elevator must return to the bottom floor or base s

80、tation immediately when the fire switch acts. The elevator should turn to normal operation mode when the fire switch is reset. Under normal operation mode, the control system</p><p>　　Each elevator has a set

81、 of 9 buttons on the car control panel, one for each floor. These buttons illuminate when they are pressed and cause the elevator to visit the corresponding floor. The illumination is canceled when the corresponding floo

82、r is visited by the elevator.</p><p>　　Each floor, except the first and the top floor, has two buttons on the floor control panel, one to request an upelevator, one to request a down-elevator. These buttons

83、illuminate when they are pressed. The illumination is canceled when an elevator visits the floor, then moves in the desired direction.</p><p>　　The buttons on the car control panel or the floor control panel

84、 are used to control the elevator’s motion.</p><p>　　The elevator cannot pass a floor if a passenger wants to get off there.</p><p>　　The elevator cannot stop at a floor unless someone wants to

85、 get off there.</p><p>　　The elevator cannot change direction until it has served all onboard passengers traveling in the current direction, and a hall call cannot be served by a car going in the reverse dir

86、ection.</p><p>　　If an elevator has no requests, it remains at its current floor with its doors closed.</p><p>　　(2)Parallel running with two elevators</p><p>　　In this situation, t

87、here are two elevators to serve the building simultaneously. It runs at 7am to 9am and 5pm to 7pm every day.</p><p>　　When an elevator reaches a level, it will test if the stop is required or not. It will st

88、op at this level when the stop is required.</p><p>　　At the same time, to balance the number of stops, the operation of two elevators will follow a certain dispatching principle.</p><p>　　An ele

89、vator doesn’t stop at a floor if another car is already stopping, or has been stopped there.</p><p>　　The normal operation of elevators is implemented by cooperation of its electric power driving system and

90、logic control system.</p><p>　　3. Software design</p><p>　　Due to the random nature of call time, call locations and the destination of passengers, the elevator control system is a typical real-

91、time, random logic control system. Here we adopted collective selective control method with siemens PLC S7-200 CPU226 and its extension modules. There are 46 input points and 46 output points in the system. The I/O point

92、s are showed in Table1.</p><p>　　Table 1 I/O address distribute</p><p>　　About software designing, we adopt the modularized method to write ladder diagram programs. The information transmission

93、 between modules is achieved by intermediate register bit of PLC.</p><p>　　The whole program is mainly composed of 10 modules: hall-call registration and display module, car-call registration and display mod

94、ule, the signal combination module, the hall-call cancel module, the elevator-location display module, the floor selection module, the moving direction control module, the door open/close module, the maintenance operatio

95、n module and the dispatching module under parallel running mode.</p><p>　　The design of the typical modules is described as follows:</p><p>　　3.1 Hall-call registration and display</p>&l

96、t;p>　　There are two kinds of calls in an elevator: hall-call and car-call. When someone presses a button on the floor control panel, the signal will be registered and the corresponding lamp will illuminate. This is ca

97、lled hall-call registration.</p><p>　　When a passenger presses a button in the elevator car, the signal will be registered and with the corresponding lamp illuminated. This is called car-call registration.&l

98、t;/p><p>　　Figure2 shows the ladder diagram of up hall-calls registration and display. The self-lock principle is used to guarantee the calls’ continuous display.</p><p>　　Figure 2 up hall-call reg

99、istration and display</p><p>　　3.2 The collective selection of the calls</p><p>　　Here the collective selection control rules are used. As showed in Figure3, M5.1-M5.7, M6.0 and M6.1 are auxilia

100、ry relays in PLC. They denote the stopping request signal of 1st to 9th floor respectively. The auxiliary relay M6.2 denotes the elevator driver’s operation signal. When there is a call in a certain floor, the stopping s

101、ignal of corresponding floor will output. When the elevator is operated by the driver, the hall-calls will not be served. And the elevator cannot pass a floor at which </p><p>　　3.3 The cancellation of the c

102、alls</p><p>　　The program of this module can make the elevator response the hall-calls which have the same direction as the car’s current direction, and when a hall-call is served, its registration will be c

103、anceled. The ladder diagram of up hall-calls’ cancellation is showed in Figure4.</p><p>　　Figure 3 The combination of the calls</p><p>　　Figure 4 The cancellation of up calls</p><p>

104、;　　In Figure4, the auxiliary relay M4.0 is the up moving flag of the elevator. When the current direction of the elevator is up, M4.0’s contacts are closed; on the contrary, when the current direction of the elevator is

105、down, M4.0’s contacts are opened. M0.1 to M0.7 denotes the car-calls’ stopping request signal of floor 2 to floor 8 respectively.</p><p>　　This program has two functions:</p><p>　　(1) Make the e

106、levator response the normal down hall-calls when it is moving down, and when a down hall-call is served, its registration is canceled.</p><p>　　(2) When the elevator is moving up, the corresponding floor’s d

107、own hall-call it passing by is not served and the registration is remained.</p><p>　　The cancellation of down hall-calls is reversed with up hall-calls.</p><p>　　3.4 Elevator’s direction</p&g