電氣專業(yè)論文文獻(xiàn)綜述.doc

精品文檔滄 州 師 范 學(xué) 院專 業(yè) 外 語 閱 讀文 獻(xiàn) 綜 述學(xué) 院 機(jī)械與電氣工程學(xué)院姓 名 劉昊 學(xué) 號 1414216125 專 業(yè) 電氣工程及其自動化班 級 2014級1班 2017 年 1 月PLC技術(shù)簡介與應(yīng)用摘要:隨著電子計(jì)算機(jī)技術(shù)的不斷發(fā)展，PLC 技術(shù)在電氣化自動控制制造與研發(fā)領(lǐng)域中的應(yīng)用變得越來越廣泛，發(fā)揮著不可替代的作用。PLC 技術(shù)在電氣設(shè)備自動化控制中的應(yīng)用是以微軟的處理器作為基礎(chǔ)，結(jié)合了現(xiàn)在的計(jì)算機(jī)技術(shù)，自動控制技術(shù)，現(xiàn)代通訊技術(shù)等的優(yōu)勢，極大的擴(kuò)充了 PLC 技術(shù)在電氣設(shè)備自動化控制應(yīng)用中的適用領(lǐng)域，有很強(qiáng)的實(shí)效性。 PLC 技術(shù)有著高靈活性、高可靠性、便捷性，和工業(yè)機(jī)器人、CAD/CAM 并稱現(xiàn)代自動化工業(yè)的三大頂梁柱。 本文介紹何為 PLC 技術(shù)，PLC 技術(shù)在電氣設(shè)備自動化控制中的優(yōu)勢與應(yīng)用，希望能有一定的借鑒作用。關(guān)鍵詞:PLC 技術(shù)；電氣設(shè)備；自動化控制一.PLC 技術(shù)的概念PLC 是英語可編程控制器 Programmable logic Controller 的縮寫，以微處理器為依托，結(jié)合通信，計(jì)算機(jī)，互聯(lián)網(wǎng)和自動控制技術(shù)開發(fā)而成的工業(yè)上的控制裝置。 PLC 技術(shù)起源于 20 世紀(jì) 70 年代，被成功的運(yùn)用于汽車工業(yè)中。 隨著 PLC 技術(shù)運(yùn)算，處理速度，控制各種功能的進(jìn)步與商業(yè)化， 它在電氣設(shè)備自動化中的應(yīng)用領(lǐng)域也變得越來越廣泛，形成了儀表-電器-計(jì)算機(jī)控制的一體化模式。 PLC 技術(shù)在產(chǎn)品中的應(yīng)用與生產(chǎn)， 是以 DCS 集散控制系統(tǒng)和 FCS 總線控制系統(tǒng)作為主要的控制形式。 PLC 技術(shù)在將來的發(fā)展中，將不僅僅是作為一個基礎(chǔ)系統(tǒng)，而是一種全分布式，開放式的控制系統(tǒng)。二.PLC的結(jié)構(gòu)P L C 技術(shù)的本質(zhì)是應(yīng)用于工業(yè)控制的計(jì)算機(jī)技術(shù)，因此，它的硬件結(jié)構(gòu)組成同大多數(shù) 計(jì)算機(jī)結(jié)構(gòu)是基本一致的， 都包括有:電源、C P U( 中央處理器)、 存儲器、 功能模塊、 通 信模塊、 輸入/ 輸出接口電路等等。三.PLC的工作原理概述第一個步驟，輸入采樣。在這個步驟當(dāng)中，可編程控制器讀取采樣數(shù)據(jù)主要通過掃描的方式，然后利用輸入I/O輸出映像區(qū)中所對應(yīng)的單元對這些數(shù)據(jù)進(jìn)行存儲。在數(shù)據(jù)采樣被輸入之后，繼續(xù)執(zhí)行輸出刷新操作對轉(zhuǎn)入用戶程序。第二個步驟，程序執(zhí)行。在用戶程序執(zhí)行的過程中，可編程控制器對用戶程序進(jìn)行掃描的執(zhí)行順序總是自上而下，在掃描的過程中，其運(yùn)算按照固定的順序和路線進(jìn)行，其中，掃描順序也是由左至右，由上至下，而掃描線路則是由用戶程序的各個觸電構(gòu)成。第三個步驟，系統(tǒng)輸出刷新。在這一階段所要完成的操作是可編程控制器在執(zhí)行完用戶程序之后的刷新。在刷新過程中，系統(tǒng)的中央處理器會根據(jù)輸入I/O輸出映像中相應(yīng)的狀態(tài)和前一階段輸入的數(shù)據(jù)來進(jìn)行鎖存電路，再完成對其他外設(shè)的驅(qū)動。四.PLC主要特點(diǎn)分析（1）有較高的性價比，功能完備。PLC 控制器內(nèi)有大量編程元件供用戶使用，具有很強(qiáng)大且完備的控制功能，還可以利用通信聯(lián)網(wǎng)實(shí)現(xiàn)集中管理但分散控制。(2)抗干擾能力強(qiáng)一方面，PLC 應(yīng)用了大規(guī)模的集成電路技術(shù)，在生產(chǎn)工藝上采用先進(jìn)的抗干擾處理技術(shù)，如內(nèi)部電源采取屏蔽、穩(wěn)壓、保護(hù)；設(shè)置獨(dú)立的輸入 / 輸出接口電路電源等措施，從自身硬件上增強(qiáng)了其抗干擾能力及設(shè)備的可靠性。另一方面，通過正確選擇接地地點(diǎn)和完善接地系統(tǒng)，以及采用密封、防塵、抗震的外殼進(jìn)行封裝，也可以起到良好的減少外界干擾的效果。通過以上措施使得 PLC 能在較為惡劣的環(huán)境中可靠的工作，并減少故障的發(fā)生率，提高了系統(tǒng)的可靠性。(3)PLC 控制器具有安裝方便、易維修、操作簡單等優(yōu)點(diǎn)，PLC 控制器出現(xiàn)故障時，其故障原因可通過其運(yùn)行和故障指示裝置檢查出，用戶在系統(tǒng)發(fā)生故障時，可立即采取措施更換模塊等措施進(jìn)行恢復(fù)，同時PLC用戶界面簡單明了，對于用戶來說很容易掌握。五.PLC在電力系統(tǒng)中的應(yīng)用現(xiàn)狀(1)順序控制。在火力發(fā)電系統(tǒng)中，其內(nèi)在輔助系統(tǒng)的工藝流程可以分為兩種方式，即開關(guān)控制和順序控制。隨著我國對能源及環(huán)境保護(hù)的重視程度越來越高，因此在火力發(fā)電行業(yè)中，其生產(chǎn)過程的資源節(jié)約已經(jīng)成為各企業(yè)管理的目標(biāo)。為達(dá)到節(jié)能減排的終極目標(biāo)，必須提高該企業(yè)輔助車間的自動化控制水平。隨著 PLC 控制技術(shù)的問世，在火力發(fā)電企業(yè)的輔助系統(tǒng)中，傳統(tǒng)繼電控制器基本被 PLC 控制系統(tǒng)代替，于此同時，隨著科技的不斷進(jìn)步，PLC控制系統(tǒng)不僅可以對單個工藝流程進(jìn)行有效控制，而且可以通過將 PLC 連接通信總線的方式來對整個生產(chǎn)環(huán)節(jié)進(jìn)行協(xié)調(diào)。（2）開關(guān)量控制斷路器控制。原來的火電系統(tǒng)內(nèi)多采用電磁型繼電器為主要元件的控制器，該系統(tǒng)采用了大量電磁元件，因此其自身的大量觸點(diǎn)大大降低了系統(tǒng)的可靠性，同時該種系統(tǒng)還具有接線復(fù)雜、維修困難等缺點(diǎn)，而近年來PLC的運(yùn)用則用大量軟繼電器代替大量的實(shí)物元 件，因此 大大提高了其可靠性，運(yùn)行人員只需進(jìn)行簡單 的分合閘操作，在操作過程中系統(tǒng)能夠根據(jù)實(shí)際能否運(yùn)行而給出相應(yīng)的指示信號。自動切換。為了加強(qiáng)供電的可靠性，備用電源 自動投人裝置多年前就應(yīng)用在火電企業(yè)當(dāng)中，最初為手動或 自動進(jìn)行供回電線路的操作，雖然該操作過程往往之需要幾秒鐘的時間，但對于有連續(xù)供 電要求的用戶來說也是不允許的，因此，為了提高供 電的可靠性，由PLC構(gòu)成 的備用電源自動投人裝置應(yīng)運(yùn)而生，其可以通過編程來使用各種運(yùn)行方式，其將采集到的一次設(shè)備 的正常運(yùn)行信號作為備用電源啟動或關(guān)閉的依據(jù)，由于該控制系統(tǒng)具有數(shù)據(jù)處理以及邏輯判斷功能，因此其不僅能完成備用電源自投的操作，且其能考慮系統(tǒng)運(yùn)行情況以及其他操作要求，同時系統(tǒng)本身具有很強(qiáng)的抗干擾能力，并具有可靠性高、接線簡單、調(diào)試操作方便以及成本低等優(yōu)點(diǎn)。(3)閉環(huán)控制泵類電機(jī)?；痣姵蓛?nèi)泵類啟動方式一般有自動啟動、機(jī)旁屏手動啟動以及現(xiàn)場控制箱手動啟動幾種。自動狀態(tài)下泵的開機(jī)時由PLC內(nèi)順控模塊根據(jù)各個泵 的累積運(yùn)行時間長短來選擇主備用泵；而機(jī)旁屏開啟方式則是需調(diào)節(jié)現(xiàn)場開關(guān)的方式來啟閉泵，其主備用泵則是根據(jù)人類對運(yùn)行時間的比較來決定每臺泵的啟閉，而若要在現(xiàn)場對其進(jìn)行操作則需將開關(guān)調(diào)至“調(diào)速器手動”檔位才能實(shí)現(xiàn)。六.PLC 在電氣自動化中的應(yīng)用前景控制與管理功能一體化。在一臺控制器上同時實(shí)現(xiàn)控制功能和信息處理功能，PLC 產(chǎn)品采用計(jì)算機(jī)信息處理技術(shù)、網(wǎng)絡(luò)通信技術(shù)和圖形顯示技術(shù)，使得 PLC 系統(tǒng)的生產(chǎn)控制功能和信息管理功能融為一體，進(jìn)一步提高 PLC 的功能，最大限度滿足現(xiàn)代化大生產(chǎn)的控制與管理的需要?，F(xiàn)代 PLC 控制技術(shù)將向體積更小、功能更強(qiáng)、價格更低、速度更快的微小型方向發(fā)展，同時也會朝著大型網(wǎng)絡(luò)化、兼容性好、功能全及可靠性高的方向發(fā)展。在網(wǎng)絡(luò)信息技術(shù)高速發(fā)展的時代，PLC 控制技術(shù)也將逐步得到優(yōu)化，也必將擁有更為廣闊的發(fā)展前景。七.PLC在電氣自動化中的發(fā)展趨勢伴隨著科技的發(fā)展，全球工業(yè)計(jì)算機(jī)控制領(lǐng)域已經(jīng)發(fā)生巨大變 革，PLC幾乎到處都 有，對于PLC控制器的核心控制軟件來講，開放式的編程組態(tài)工具軟件以及開放式通信網(wǎng)絡(luò)技術(shù)的突破，將PLC推向了更加開放的工業(yè)控制行業(yè)。PLC控制系統(tǒng)在高端應(yīng)用方面，將和工業(yè)PC控制系統(tǒng)相媲美，因?yàn)檫@兩者在微處理器和內(nèi)存芯片方面十分相似，將來的發(fā)展趨勢是將更多的功能進(jìn)一步集成到一個控制箱內(nèi)，以方便用戶的操作和使用，像順序控制和過程控制將會采用功能化方式進(jìn)行處理，其他類似運(yùn)動控制等也能夠共享到相同的控制結(jié)構(gòu)體系中?？梢韵嘈?，PLC技術(shù)的發(fā)展繼續(xù)沿著開放式控制系統(tǒng)的方向，尤其是基于工業(yè)PC的控制系統(tǒng)。為了更好的提供用戶使用，PLC在人機(jī)界面方面要做的完美、通信設(shè)備要更加完備、現(xiàn)場總線通信能力要更加的成熟，這樣才能更好地適應(yīng)各種不同工業(yè)控制場合的需求。除了在靈活性方面比傳統(tǒng)PLC具有截然不同的優(yōu)勢外，還要做到能夠縮短系統(tǒng)投放到市場的周期，并能降低系統(tǒng)投資費(fèi)用，提高從工廠底層到企業(yè)辦公自動化的數(shù)據(jù)信息流動效率等，這將是PLC未來發(fā)展不可抵擋的趨勢。結(jié)論:綜上所述，PLC 技術(shù)在電氣自動化控制中是一項(xiàng)先進(jìn)的技術(shù)，它克服了傳統(tǒng)電氣自動化控制系統(tǒng)的諸多缺點(diǎn)，減少了材料消耗，減少了維護(hù)工作，幫助企業(yè)節(jié)省資源，提高企業(yè)的工作效率。同時 PLC 在電氣自動化控制中的應(yīng)用又需要進(jìn)一步的發(fā)展，要突破現(xiàn)有的技術(shù)瓶頸，做到在各種環(huán)境下都能讓PLC 運(yùn)用到電氣自動化的控制之中，同時，需要對現(xiàn)有的 PLC 技術(shù)進(jìn)行改進(jìn)，使之能在高溫高壓以及高電磁輻射等各種復(fù)雜的環(huán)境下進(jìn)行工作，這樣 PLC 在電氣自動化控制中的應(yīng)用才能得到充分的擴(kuò)展和全面的開發(fā)利用。參考文獻(xiàn)1 劉鐵中.PLC技術(shù)在電氣設(shè)備自動化控制中的應(yīng)用.J.科技視界，20132 于軍，苗百春.PLC技術(shù)在電氣自動化中的應(yīng)用.J.科技資訊，20133 張俊莉.PLC在電氣自動化中的應(yīng)用探究.A.第二屆“科協(xié)文化中關(guān)村論壇”論文集.4 王華琳.PLC在電氣自動化控制中的應(yīng)用.J.信息與電腦（理論版），20135 孫勝濤.PLC 在電氣自動化控制中的應(yīng)用分析.J.電子技術(shù)與軟件工程，2013，Introduction and application of PLC technologyAbstract: With the continuous development of computer technology, PLC technology in the electric automatic control is becoming more and more widely applied in the field of manufacturing and research and development, play an irreplaceable role. PLC technology in the application of the electric equipment automation control based on Microsofts processor as the foundation, combined with the present computer technology, automatic control technology, modern communication technology and other advantages, greatly extend the application of PLC technology in the electric equipment automation control applicable areas, have very strong effectiveness. PLC technology has high flexibility, high reliability, convenience, and industrial robots, CAD/CAM and three big pillar of modern industrial automation. This paper introduces what is the PLC technology, PLC technology in electrical equipment of the advantage and application of automation control, hope to have certain reference function.Keywords: The PLC technology, Electrical equipment; Automatic control1.The concept of PLC technologyIs English PLC Programmable Controller Programmable logic Controller, which is based on microprocessor, combined with communication, computer, Internet and automatic control technology on the development of industrial control device. PLC technology originated in the 1970 s, has been successfully applied in automobile industry. As the technology of PLC, processing speed, control the progress of the various functions and commercialized, its applications in electrical equipment automation is also becoming more and more widely, formed the instrument - appliances - the integration of computer control mode. The PLC technology in the application of products and production, with DCS DCS and FCS bus control system as the main form. The development of PLC technology in the future, will not just as a basic system, but a whole distributed, open control system.2.The structure of the PLCThe essence of P L C technology is applied in the industrial control computer technology, as a result, the hardware structure is the basic consistent with most computer structure, all include: power supply, C P U , memory module, function module, letter, input/output interface circuit and so on.3. The working principle of PLC The first step, the input samples. In this step, programmable controller read sampling data mainly through the way of scanning, and then use the input in the I/O output image area of the storage unit of the data. After the sampling data is input, continue to implement the output refresh operation to turn to the user program.The second step, the program execution. In the process of the user of the program execution, programmable controller for the user program to scan the execution order from top to bottom, always in the process of scanning, its operation shall be carried out in accordance with the fixed order and route, among them, the scanning sequence is from left to right, from top to bottom, and the scanning line is made up of each user program to get an electric shock.The third step, the system output refresh. The operation to be completed at this stage is a programmable controller to refresh after the execution of the user program. In the refresh process, the system CPU I/O output will be based on the input image in the corresponding state and the previous phase of the input data to latch circuit, then complete the drive for other peripherals.4. PLC main characteristic analysis(1) Has high cost performance, fully functional. PLC controller contains a large number of programming components used by users, has the very strong and complete control function, still can use communication network to realize centralized management but decentralized control.(2) Strong anti-interference ability on the one hand, the application of PLC on a large scale integrated circuit technology, adopts advanced anti-jamming processing techniques in the production process, such as internal power to shield, voltage regulator, protection; Set up the independent power supply, input/output interface circuit from their own hardware to enhance its anti-jamming ability and reliability of equipment. On the other hand, through the correct selection of grounding location and improve the system, and the sealing, dustproof, seismic encapsulation shell, also can have good reduce interference effect. Through the above measures can make the PLC in a relatively harsh environment and reliable work, and to reduce the incidence of failure, improve the reliability of the system.(3) The PLC controller has the advantages of convenient installation, easy maintenance, simple operation, PLC controller failure, the failure cause by its operation and fault indication device, check out the users in the system failure occurs, immediately take measures to replace modules such as measures to restore, PLC user interface simple and clear at the same time, it is very easy for users to master.5. Application of PLC in power system are reviewed(1) Sequential control. In the thermal power system, its internal auxiliary system of technological process can be divided into two ways, namely, switch control and sequence control. Along with our countrys emphasis on energy and environmental protection degree is more and more high, so in the thermal power industry, the production process of saving resources have become the target of each enterprise management. In order to reach the ultimate goal of energy conservation and emissions reduction, it is necessary to improve the automatic control level of the enterprise auxiliary workshop. With the advent of PLC control technology, in the auxiliary system of thermal power enterprises, the traditional relay controller is replaced by PLC control system, basic at the same time, with the constant progress of science and technology, PLC control system can not only to a single technological process for effective control, and be able to connect to PLC communication alwaysTo coordinate the way for the whole production line.(2) the switch quantity controlCircuit breaker control. Original type thermal power system with electromagnetic relay as the main components of the controller, the system USES a large amount of electromagnetic components, so its a lot of contact greatly reduce the reliability of the system, simultaneously this system also has the disadvantages such as complex wiring, maintenance difficulties, and the application of PLC in recent years with a lot of soft relay instead of a lot of physical yuan, accordingly Greatly improve the reliability, operators need to closing operation, simple points in the process of operating system can be based on the actual operation and the corresponding indicator is given.Automatic switching. In order to enhance the reliability of power supply and standby power automatic device years ago used in thermal power enterprises, initially for the back line for manual or automatic operation, while the operating process often takes a few seconds, but for continuous electrical requirements of the user is not allowed, therefore, in order to improve the reliability of supply electricity, composed of PLC of standby power automatic device, it can be programmed to use all kinds of operation mode, it will be a equipment normal operation signals were collected as a basis for the standby power on or off, due to the control system with functions of data processing and logical judgment, so it can not only complete the reserve power source operation, and it can consider the system running situation and other operation requirements, at the same time, the system itself has a strong anti-interference ability, and has high reliability, simple wiring, debugging, convenient operation and low cost etc.(3) closed loop controlPump motor. Thermal power into the general pump startup mode automatically start, screen machine manual start and run several field manual control box. Automatic condition of pump is powered by PLC in sequence control module based on the accumulation of each pump running length of time to choose the main spare pump; And beside the machine screen open means is to adjust the switch to open/close pump, its main standby pump is based on human compare to run time to determine each pump type, while in the scene to manipulate it will switch to manual governor gear to achieve.6. The application prospects of PLC in electrical automationControl and management integration. On a controller to control and information processing functions at the same time, PLC adopts computer information processing technology and network communication technology and graphics display technology, makes the production control function of PLC system and information management functions, to further improve the function of PLC, the maximum meet the needs of the modern production control and management.Modern PLC control technology to a smaller, more powerful and cheaper and faster microminiature direction, as well as toward a large network, good compatibility, full functions and high reliability. In the era of network information technology high speed development, PLC control technology will gradually optimized, will surely have a broader development prospects.7. The development trend of PLC in electrical automationAlong with the development of science and technology, tremendous changes have occurred in the field of global industrial computer control, PLC, almost everywhere, for the core of the PLC controller, control software, programming configuration tool software and open communication network technology breakthrough, PLC will be more open to the industrial control industry.PLC control system in high-end applications, and industrial PC control system, which is quite similar in terms of the microprocessor and memory chip, the development trend of the future will be more further integrated into the function of a control box, with convenient operation and use of the user, such as sequence control and process control will be using functional way to deal with, other similar motion control and so on also can share the same control structure system. Are to be believed, the development of PLC technology to continue along the direction of the open control system, especially the control system based on industrial PC. In order to better provide users, PLC in the aspect of man-machine interface to do perfect, communications equipment more complete, fieldbus communication ability will be more mature, so as to better adapt to the demand of various industrial control occasions. In addition to the flexibility than traditional PLC has a distinct advantage, but also can shorten the cycle of system into the market, and can reduce the investment cost of the system and improve the bottom from the factory to the data flow of information efficiency of enterprise office automation, etc., this will be the future development of PLC irresistible trend.Conclusion: To sum up, the P