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1、<p><b>  附錄</b></p><p><b>  附錄A 外文文獻</b></p><p>  Elevator System Based on PLC</p><p>  Composed by the order of relay control system is a realization o

2、f the first elevator control method. However, to enter the nineties, with the development of science and technology and the widespread application of computer technology, the safety of elevators, reliability of the incre

3、asingly high demand on the relay control weaknesses are becoming evident.</p><p>  Elevator control system relays the failure rate high, greatly reduces the reliability and safety of elevators, and escalator

4、s stopped often to take with the staff about the inconvenience and fear. And the event rather than taking the lift or squat at the end of the lift will not only cause damage to mechanical components, but also personal ac

5、cident may occur. </p><p>  Programmable Logic Controller (PLC) is the first order logic control in accordance with the needs of developed specifically for industrial environment applications to operate the

6、electronic digital computing device. Given its advantages, at present, the relay control the lift has been gradually replaced by PLC control. At the same time, AC variable frequency motor speed control technology, the wa

7、y the lift drag speed has been a gradual transition from DC to AC frequency converter. Thus, PLC cont</p><p>  1. PLC elevator control advantages</p><p>  (1) used in elevator control PLC, with

8、software for automatic control of lift operation, reliability greatly increased.</p><p>  (2) layer was removed and a majority of the relay, the control system structure is simple, to simplify the external c

9、ircuit.</p><p>  (3) PLC can be a variety of complex control system, easy to add or change control functions.</p><p>  (4) PLC can be automated fault detection and alarm display to improve the o

10、peration of security and ease of maintenance.</p><p>  (5) for the group control the allocation and management, and improve the efficiency of elevator operation.</p><p>  (6) do not need to chan

11、ge the control scheme changes when the hardware connection.</p><p>  2. VVVF elevator control characteristics</p><p>  With the power electronics, microelectronics and computer technology to con

12、trol the rapid development of technology, communication technology VVVF also a very rapid rate. AC variable frequency motor speed control technology is the power to improve the process in order to improve product quality

13、 and improving the environment and promoting technological progress as a primary means. Frequency of its excellent performance and the speed brake from a smooth performance, high efficiency, high power fac</p><

14、;p>  Exchange characteristics of VVVF Elevator.</p><p>  (1)low energy consumption.</p><p>  (2)low load circuit, the required emergency power supply device of small In the acceleration stage

15、, the required start-up current of less than 2.5 times the rated current. Peak starting current and time is short. Since the starting current is drastically reduced, so power consumption and power supply cable diameter c

16、an be reduced a lot. Required for emergency power supply devices are also relatively small size. </p><p>  (3) high reliability and long service life. </p><p>  (4)good comfort Elevator operatio

17、n is best to follow the speed curve of a given operation. Their characteristics can be adapted to human feelings, and to ensure that noise operation, smooth brake Ping layer and high precision </p><p>  (5)

18、Stable noise-free </p><p>  (6) In the car, the engine room and adjacent areas to ensure that noise. Because their systems use a high clock frequency. Always produce a true sine wave power supply current yet

19、. Motor torque ripple does not appear. Therefore, to eliminate vibration and noise. </p><p>  3. Elevator control technology</p><p>  The so-called elevator control technology refers to the elev

20、ator drive system and electrical control system of automatic control. 70 as the 20th century in China's elevator was marked by the exchange of two-speed elevator. Its speed is used to change the elevator traction mot

21、or of the very few, two or multi-level approach to the number of windings, very few of them as high-speed winding of the winding, a very few number of windings as the low-speed winding. Windings for high-speed elevator-s

22、peed</p><p>  The early 80s, VVVF inverter controlled variable lift system available. It uses AC motor drives, are able to reach the level of DC motor, control the speed of the current has reached 6 m / sec.

23、 Its small size, light weight, high efficiency, energy saving, including the past almost all the advantages of the lift. Is the latest elevator drive system.</p><p>  Operation in vertical lift, there is als

24、o the starting point of the terminus station. For more than three-story elevator buildings, the starting point of the terminal stations and stops between the had not, the starting point for these stations at the first fl

25、oor of the terminal located at the highest floor. Starting point in the first floor of the station known as base stations, known as the starting point at both ends of the terminal stations and stations at both ends of in

26、termediate stops bet</p><p>  Outside the station has a call box, box set are used by staff for elevator call button or touch the call button, the general ends of the lift stations in the call box on the Set

27、tings button or touch of a button. Middle layer of the station set up the call box button or touch button 2. No drivers for the control of elevators, at various stations are set up calls me on a button or touch button. E

28、levator car and the internal settings (except for debris elevator) to manipulate me. Control box switch</p><p>  As the elevator call box outside the base station, in addition to set up a call button or touc

29、h button, but also set a key switch in order to work the elevator clearance. Drivers or management staff to open the elevator to the base station can wriggle through a dedicated key to the key switch. Close the elevator

30、in place to automatically cut off the elevator control power supply or power supply.</p><p>  4. PLC Control Elevator Design</p><p>  With the continuous development of urban construction, the i

31、ncreasing high-rise buildings, elevators and life in the national economy has a broad application. Elevator high-rise buildings as a means of transport in the vertical run of daily life has been inextricably linked with

32、people. In fact the lift is based on external call control signals, as well as the laws of their own, such as running, and the call is random, the lift is actually a man-machine interactive control system, simple to use

33、</p><p>  5. Elevator control system characteristics</p><p>  Operation of the lift curve is above the start to run comfort indicators lift the key features, and comfort are directly related wit

34、h the acceleration, according to control theory, for a certain amount of change according to the law must be directly controlled, for elevator control system, according to the ideal acceleration curve acceleration feedba

35、ck to be used, in accordance with the motor torque equation: M-MZ = ΔM = J (dn / dt), can be seen reflected in the rate of change of acceleration of</p><p><b>  附錄B 中文翻譯</b></p><p> 

36、 PLC控制下的電梯系統(tǒng)</p><p>  由繼電器組成的順序控制系統(tǒng)是最早的一種實現(xiàn)電梯控制的方法。但是,進入九十年代,隨著科學技術的發(fā)展和計算機技術的廣泛應用,人們對電梯的安全性、可靠性的要求越來越高,繼電器控制的弱點就越來越明顯。 </p><p>  電梯繼電器控制系統(tǒng)故障率高,大大降低了電梯的可靠性和安全性,經(jīng)常造成停梯,給乘用人員帶來不便和驚憂。且電梯一旦發(fā)生沖頂或蹲底,不

37、但會造成電梯機械部件損壞,還可能出現(xiàn)人身事故。</p><p>  可編程序控制器(PLC)最早是根據(jù)順序邏輯控制的需要而發(fā)展起來的,是專門為工業(yè)環(huán)境應用而設計的數(shù)字運算操作的電子裝置。鑒于其種種優(yōu)點,目前,電梯的繼電器控制方式己逐漸被PLC控制所代替。同時,由于電機交流變頻調(diào)速技術的發(fā)展,電梯的拖動方式己由原來直流調(diào)速逐漸過渡到了交流變頻調(diào)速。因此,PLC控制技術加變頻調(diào)速技術己成為現(xiàn)代電梯行業(yè)的一個熱點。&l

38、t;/p><p>  1. PLC控制電梯的優(yōu)點</p><p>  (1)在電梯控制中采用了PLC,用軟件實現(xiàn)對電梯運行的自動控制,可靠性大大提高。</p><p>  (2)去掉了選層器及大部分繼電器,控制系統(tǒng)結(jié)構(gòu)簡單,外部線路簡化。</p><p>  (3)PLC可實現(xiàn)各種復雜的控制系統(tǒng),方便地增加或改變控制功能。</p>

39、<p>  (4) PLC可進行故障自動檢測與報警顯示,提高運行安全性,并便于檢修。</p><p>  (5)用于群控調(diào)配和管理,并提高電梯運行效率。</p><p>  (6)更改控制方案時不需改動硬件接線。</p><p>  2.電梯變頻調(diào)速控制的特點</p><p>  隨著電力電子技術、微電子技術和計算機控制技術的飛速發(fā)

40、展,交流變頻調(diào)速技術的發(fā)展也十分迅速。電動機交流變頻調(diào)速技術是當今節(jié)電、改善工藝流程以提高產(chǎn)品質(zhì)量和改善環(huán)境、推動技術進步的一種主要手段。變頻調(diào)速以其優(yōu)異的調(diào)速性能和起制動平穩(wěn)性能、高效率、高功率因數(shù)和節(jié)電效果,廣泛的適用范圍及其它許多優(yōu)點而被國內(nèi)外公認為最有發(fā)展前途的調(diào)速方式</p><p>  交流變頻調(diào)速電梯的特點</p><p><b>  ⑴ 能源消耗低</b&g

41、t;</p><p> ?、?電路負載低,所需緊急供電裝置小</p><p>  在加速階段,所需起動電流小于2.5倍的額定電流。且起動電流峰值時間短。由于起動電流大幅度減小,故功耗和供電纜線直徑可減小很多。所需的緊急供電裝置的尺寸也比較小。</p><p>  ⑶ 可靠性高,使用壽命長。</p><p><b> ?、?舒適感好&

42、lt;/b></p><p>  電梯運行是跟隨最佳給定的速度曲線運行的。其特性可適應人體感受,并保證運行噪聲小,制動平穩(wěn)</p><p><b> ?、?平層精度高</b></p><p><b> ?、?運行平穩(wěn)無噪聲</b></p><p>  在轎廂內(nèi),機房內(nèi)及鄰近區(qū)域確保噪聲小。因為

43、其系統(tǒng)中采用了高時鐘頻率。始終產(chǎn)生一個不失真的正弦波供電電流。電動機不會出現(xiàn)轉(zhuǎn)距脈動。因此,消除了振動和噪聲。</p><p><b>  3.電梯控制技術</b></p><p>  所謂電梯控制技術是指電梯的傳動系統(tǒng)及操縱系統(tǒng)的電氣自動控制。作為我國20世紀70年代電梯的主要標志是交流雙速電梯。其調(diào)速方法是采用改變電梯牽引電動機的極對數(shù),兩種或兩種不同級對數(shù)的繞組

44、,其中極數(shù)少的繞組稱為高速繞組,極數(shù)多的繞組稱為低速繞組。高速繞組用于電梯的起動及穩(wěn)速運行,低速繞組用于制動及電梯的維修。</p><p>  80年代初,VVVF變頻變壓系統(tǒng)控制的電梯問世。它采用交流電動機驅(qū)動,卻可以達到直流電動機的水平,目前控制速度已達6米/秒。它的體積小,重量輕,效率高,節(jié)省能源等幾乎包括了以往電梯的所有優(yōu)點。是目前最新的電梯拖動系統(tǒng)?! ‰娞菰诖怪边\行過程中,有起點站也有終點站。對于三

45、層樓以上的建筑物的電梯,起點站和終點站之間還沒有??空?,起點站設在一樓,終點站設在最高樓。設在一樓的起點站稱為基站,起點站和終點站稱為兩端站,兩端站之間稱為中間站。</p><p>  各站廳外設有召喚箱,箱上設置有供乘用人員召喚電梯用的召喚按鈕或觸鈕,一般電梯在兩端站的召喚箱上各設置一只按鈕或觸鈕。中間層站的召喚箱各設置兩只按鈕或觸鈕。對于無司機控制的電梯,在各層站的召喚箱上均設置一只按鈕或觸鈕。而電梯的轎廂內(nèi)

46、部設置有(雜物電梯除外)操縱箱。操縱箱上設置有手柄開關或與層站對應的按鈕或觸鈕,操縱箱上的按鈕或觸鈕城內(nèi)指令按鈕或觸鈕。外指令按鈕或觸鈕發(fā)出的電信號稱為外指令信號,內(nèi)指令按鈕或觸鈕發(fā)出的電信號成為內(nèi)指令信號。20世紀80年代中期后,觸鈕已被微動按鈕所取代。</p><p>  作為電梯基站的廳外召喚箱,除設置一只召喚按鈕或觸鈕外,還設置一只鑰匙開關,以便下班關電梯時。司機或管理人員把電梯開到基站后,可以通過專用鑰

47、匙扭動該鑰匙開關。把電梯的廳門關閉妥當后,自動切斷電梯控制電源或動力電源。</p><p>  4. PLC控制電梯的設計</p><p>  隨著城市建設的不斷發(fā)展,高層建筑不斷增多,電梯在國民經(jīng)濟和生活中有著廣泛的應用。電梯作為高層建筑中垂直運行的交通工具已與人們的日常生活密不可分。實際上電梯是根據(jù)外部呼叫信號以及自身控制規(guī)律等運行的,而呼叫是隨機的,電梯實際上是一個人機交互式的控制系

48、統(tǒng),單純用順序控制或邏輯控制是不能滿足控制要求的,因此,電梯控制系統(tǒng)采用隨機邏輯方式控制。目前電梯的控制普遍采用了兩種方式,一是采用微機作為信號控制單元,完成電梯信號的采集、運行狀態(tài)和功能的設定,實現(xiàn)電梯的自動調(diào)度和集選運行功能,拖動控制則由變頻器來完成;第二種控制方式用可編程控制器(PLC)取代微機實現(xiàn)信號集選控制。從控制方式和性能上來說,這兩種方法并沒有太大的區(qū)別。國內(nèi)廠家大多選擇第二種方式,其原因在于生產(chǎn)規(guī)模較小,自己設計和制造微

49、機控制裝置成本較高;而PLC可靠性高,程序設計方便靈活,抗干擾能力強、運行穩(wěn)定可靠等特點,所以現(xiàn)在的電梯控制系統(tǒng)廣泛采用可編程控制器來實現(xiàn)。</p><p>  5、電梯控制系統(tǒng)特性</p><p>  在電梯運行曲線中的啟動段是關系到電梯運行舒適感指標的主要環(huán)節(jié),而舒適感又與加速度直接相關,根據(jù)控制理論,要使某個量按預定規(guī)律變化必須對其進行直接控制,對于電梯控制系統(tǒng)來說,要使加速度按理想

50、曲線變化就必須采用加速度反饋,根據(jù)電動機的力矩方程式:M—MZ=ΔM=J(dn/dt),可見加速度的變化率反映了系統(tǒng)動態(tài)轉(zhuǎn)距的變化,控制加速度就控制系統(tǒng)的動態(tài)轉(zhuǎn)距ΔM=M—MZ。故在此段采用加速度的時間控制原則,當啟動上升段速度達到穩(wěn)態(tài)值的90%時,將系統(tǒng)由加速度控制切換到速度控制,因為在穩(wěn)速段,速度為恒值控制波動較小,加速度變化不大,且采用速度閉環(huán)控制可以使穩(wěn)態(tài)速度保持一定的精度,為制動段的精確平層創(chuàng)造條件。在系統(tǒng)的速度上升段和穩(wěn)速段

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