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1、中文摘要隨著火電廠規(guī)模和單機(jī)容量的擴(kuò)大,給煤機(jī)在整個(gè)選煤系統(tǒng)中的作用越來越大,目前300MW及以上的大機(jī)組的鍋爐一般采用直吹式制粉系統(tǒng),即一臺磨煤機(jī)配備若干臺給煤機(jī),磨煤機(jī)的煤粉直接進(jìn)入鍋爐燃燒器燃燒。這樣鍋爐的給煤量就完全由給煤機(jī)決定,給煤機(jī)的控制性能就顯得尤為重要。給煤機(jī)給煤量過多會加大皮帶電機(jī)負(fù)荷,增加皮帶磨損程度,增加設(shè)備故障發(fā)生幾率,影響生產(chǎn)效率;給煤機(jī)給煤量過少又會降低生產(chǎn)效率,影響效益。稱重式給煤機(jī)是一種可均勻、連續(xù)、定量地給煤到磨煤機(jī)中的設(shè)備,并且可以在給煤過程中對煤連續(xù)稱重,同時(shí)根據(jù)燃燒系統(tǒng)需求的煤量信號,隨時(shí)調(diào)節(jié)給煤
2、量。因此稱重給煤機(jī)廣泛適用于電力、冶金等各行業(yè)的工業(yè)鍋爐的連續(xù)給煤??删幊炭刂破鱌LC因具有高可靠性、易集中控制的優(yōu)點(diǎn),使其在工業(yè)控制中得到廣泛應(yīng)用。本設(shè)計(jì)用S7-200PLC和MCGS監(jiān)控軟件實(shí)現(xiàn)稱重式給煤機(jī)監(jiān)控系統(tǒng)的設(shè)計(jì)、調(diào)試等。通過上位機(jī)的監(jiān)控畫面,我們便可以對現(xiàn)場的機(jī)器運(yùn)行狀況一目了然。本文重點(diǎn)介紹了可編程控制器在給煤機(jī)稱重監(jiān)控系統(tǒng)中的應(yīng)用。分析了目前給煤機(jī)在電廠中的重要地位,根據(jù)給煤機(jī)控制系統(tǒng)的現(xiàn)有狀況,詳細(xì)闡述了改造后系統(tǒng)的工作原理及方式、控制系統(tǒng)的組成、PLC應(yīng)用領(lǐng)域、發(fā)展方向以及如何設(shè)計(jì)梯形圖在本文中都一一進(jìn)行了介紹。并
3、且經(jīng)過模擬試驗(yàn),證明了改造后系統(tǒng)運(yùn)行達(dá)到了經(jīng)濟(jì)高效穩(wěn)定的預(yù)定要求。因此用PLC及上位機(jī)監(jiān)控實(shí)現(xiàn)對給煤機(jī)的控制是現(xiàn)代化火電廠的需要。關(guān)鍵詞稱重式給煤機(jī),可編程序控制器,上位機(jī),監(jiān)控系統(tǒng)AbstractWiththescaleofthepowerplantandsinglecapacityexpansion,toploughinthewholeselectiontheroleofcoalsystemismoreandmorebig,Ofthe300MWandabovetheboilergenerallyUSESthestraightblow
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7、oal.PLCprogrammablecontrollerwithhighreliability,easyfortheadvantagesofcentralizedcontrol,sothatintheindustrycontrolhavebeenwidelyused.ThisdesignwithS7-200PLCandMCGSsoftwarerealizationweighingtypemonitoringtoploughthedesignofmonitoringandcontrolsystem,commissioning,etc.B
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