傳統的(de)電力拖動(dong)采用(yong)繼電器和(he)接觸器作為主(zhu)要的(de)控(kong)制(zhi)(zhi)手段,但隨著經(jing)濟發展(zhan)結構的(de)不(bu)斷(duan)變革和(he)社會改革的(de)深化(hua),這種控(kong)制(zhi)(zhi)方式已經(jing)無法滿足電力事業發展(zhan)的(de)需(xu)求。PLC在滿足電力拖動(dong)系統控(kong)制(zhi)(zhi)要求的(de)同(tong)時還可以(yi)提高系統的(de)自(zi)動(dong)化(hua)水(shui)平,此外(wai)目前(qian)PLC的(de)中央(yang)處理器技(ji)術與通(tong)信技(ji)術進行了融合,應用(yong)水(shui)平和(he)應用(yong)效果(guo)也得到(dao)了顯著的(de)提升。
1 PLC技術概(gai)述
PLC也(ye)就(jiu)是可編(bian)程(cheng)邏輯控制(zhi)器(qi)(qi)(ProgrammableLogicController),它(ta)可以(yi)(yi)進(jin)行(xing)編(bian)程(cheng)并將編(bian)程(cheng)好的程(cheng)序存(cun)儲,承擔存(cun)儲器(qi)(qi)的功(gong)能,此外還可以(yi)(yi)按照既定的內部程(cheng)序實現邏輯運算、定時、控制(zhi)等功(gong)能,對生產機(ji)械(xie)設(she)備進(jin)行(xing)全過程(cheng)的監視和控制(zhi)。PLC主要(yao)包括、電源、儲存(cun)器(qi)(qi)、功(gong)能模塊、CPU以(yi)(yi)及通信模塊幾(ji)部分。
輸(shu)入(ru)采樣是PLC工作的(de)(de)(de)(de)(de)(de)首要環(huan)節,之(zhi)后(hou)可以(yi)(yi)根據(ju)采集的(de)(de)(de)(de)(de)(de)數據(ju)信(xin)息(xi)的(de)(de)(de)(de)(de)(de)內(nei)容執行(xing)(xing)(xing)用戶程(cheng)序(xu)(xu),并將(jiang)(jiang)處(chu)理后(hou)的(de)(de)(de)(de)(de)(de)信(xin)息(xi)輸(shu)出刷(shua)新。上(shang)述工作執行(xing)(xing)(xing)完畢后(hou)PLC的(de)(de)(de)(de)(de)(de)一(yi)個(ge)掃(sao)描(miao)(miao)周(zhou)(zhou)期(qi)結束(shu),之(zhi)后(hou)進行(xing)(xing)(xing)下一(yi)次的(de)(de)(de)(de)(de)(de)掃(sao)描(miao)(miao),重復該流程(cheng)。圖(tu)1為(wei)PLC一(yi)個(ge)掃(sao)描(miao)(miao)周(zhou)(zhou)期(qi)的(de)(de)(de)(de)(de)(de)簡要示(shi)意圖(tu)。PLC的(de)(de)(de)(de)(de)(de)信(xin)息(xi)錄入(ru)主要是通過(guo)掃(sao)描(miao)(miao)的(de)(de)(de)(de)(de)(de)形式來實現(xian)的(de)(de)(de)(de)(de)(de),PLC會將(jiang)(jiang)采集的(de)(de)(de)(de)(de)(de)樣本信(xin)息(xi)存(cun)儲在特定(ding)的(de)(de)(de)(de)(de)(de)I/O映象單元內(nei)。PLC的(de)(de)(de)(de)(de)(de)用戶程(cheng)序(xu)(xu)執行(xing)(xing)(xing)需(xu)要遵循(xun)一(yi)定(ding)的(de)(de)(de)(de)(de)(de)順序(xu)(xu),一(yi)般來說(shuo)會采取從(cong)上(shang)及下以(yi)(yi)及從(cong)左及右的(de)(de)(de)(de)(de)(de)掃(sao)描(miao)(miao)順序(xu)(xu),對(dui)(dui)掃(sao)描(miao)(miao)的(de)(de)(de)(de)(de)(de)信(xin)息(xi)進行(xing)(xing)(xing)邏輯(ji)運算,并將(jiang)(jiang)運算顯(xian)示(shi)在相(xiang)對(dui)(dui)應的(de)(de)(de)(de)(de)(de)RAM存(cun)儲區內(nei),狀態(tai)以(yi)(yi)及指令的(de)(de)(de)(de)(de)(de)執行(xing)(xing)(xing)都可以(yi)(yi)作為(wei)用戶程(cheng)序(xu)(xu)執行(xing)(xing)(xing)的(de)(de)(de)(de)(de)(de)內(nei)容。當用戶程(cheng)序(xu)(xu)執行(xing)(xing)(xing)結束(shu)后(hou)進入(ru)最后(hou)的(de)(de)(de)(de)(de)(de)階段輸(shu)出刷(shua)新,PLC完成一(yi)個(ge)掃(sao)描(miao)(miao)周(zhou)(zhou)期(qi)的(de)(de)(de)(de)(de)(de)工作。
2 PLC在(zai)電力拖(tuo)動(dong)一體(ti)化(hua)中(zhong)的應用分析
2.1過程控制
模(mo)(mo)擬(ni)量(liang)(liang)(liang)是PLC實(shi)現電(dian)(dian)力(li)拖(tuo)動(dong)系(xi)統(tong)(tong)過(guo)(guo)程(cheng)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)的(de)(de)(de)主要(yao)方(fang)式,不同生產企業(ye)的(de)(de)(de)電(dian)(dian)力(li)拖(tuo)動(dong)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)系(xi)統(tong)(tong)存在差別,模(mo)(mo)擬(ni)量(liang)(liang)(liang)的(de)(de)(de)具(ju)體(ti)內(nei)容也各不相(xiang)同。過(guo)(guo)程(cheng)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)需(xu)要(yao)參考模(mo)(mo)擬(ni)量(liang)(liang)(liang)需(xu)要(yao)滿足連續(xu)變(bian)化的(de)(de)(de)特征,常見的(de)(de)(de)PLC過(guo)(guo)程(cheng)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)模(mo)(mo)擬(ni)量(liang)(liang)(liang)有(you)壓(ya)力(li)、溫度、電(dian)(dian)壓(ya)等等。通過(guo)(guo)PLC的(de)(de)(de)應用(yong)對電(dian)(dian)力(li)拖(tuo)動(dong)系(xi)統(tong)(tong)的(de)(de)(de)模(mo)(mo)擬(ni)量(liang)(liang)(liang)數值(zhi)進行(xing)實(shi)時的(de)(de)(de)采集和處理,將相(xiang)關(guan)參數的(de)(de)(de)歷史值(zhi)與當前(qian)值(zhi)進行(xing)比對,并根據(ju)分析(xi)的(de)(de)(de)結果生成相(xiang)應的(de)(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)系(xi)統(tong)(tong)指令(ling)發送到(dao)具(ju)體(ti)的(de)(de)(de)執行(xing)結構,完(wan)成電(dian)(dian)力(li)拖(tuo)動(dong)一體(ti)化的(de)(de)(de)遠程(cheng)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi),系(xi)統(tong)(tong)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)的(de)(de)(de)自動(dong)化水平大大提高。目(mu)前(qian)以(yi)PLC技(ji)術作為支撐的(de)(de)(de)遠程(cheng)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)技(ji)術已(yi)經在企業(ye)生產的(de)(de)(de)電(dian)(dian)力(li)拖(tuo)動(dong)一體(ti)化中得(de)到(dao)了廣泛的(de)(de)(de)應用(yong)。
2.2通信控制(zhi)
目前可編程(cheng)邏輯(ji)控(kong)(kong)(kong)(kong)制(zhi)(zhi)器已經可以通(tong)(tong)(tong)過通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)技(ji)術的(de)嵌入實(shi)現與設(she)備之(zhi)間的(de)通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)。通(tong)(tong)(tong)過PLC技(ji)術的(de)應(ying)(ying)用電(dian)力(li)拖動一體(ti)化(hua)系統控(kong)(kong)(kong)(kong)制(zhi)(zhi)中(zhong)心可以與設(she)備進行實(shi)時(shi)的(de)通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin),從而提高(gao)控(kong)(kong)(kong)(kong)制(zhi)(zhi)的(de)實(shi)效性。PLC的(de)通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)控(kong)(kong)(kong)(kong)制(zhi)(zhi)具體(ti)包括(kuo)控(kong)(kong)(kong)(kong)制(zhi)(zhi)器相互之(zhi)間的(de)通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)控(kong)(kong)(kong)(kong)制(zhi)(zhi)與控(kong)(kong)(kong)(kong)制(zhi)(zhi)器與其(qi)他(ta)設(she)備之(zhi)間的(de)通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)控(kong)(kong)(kong)(kong)制(zhi)(zhi)兩大(da)類,將通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)技(ji)術與自動化(hua)控(kong)(kong)(kong)(kong)制(zhi)(zhi)系統相結合有(you)利于(yu)實(shi)現電(dian)力(li)拖動一體(ti)化(hua)的(de)工業(ye)生產自動化(hua)網絡的(de)構(gou)建。目前PLC通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)技(ji)術應(ying)(ying)用水(shui)平日趨成(cheng)熟,各大(da)PLC生產廠商也對(dui)此給(gei)予了足夠的(de)關(guan)注,PLC通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)模塊(kuai)的(de)功能性和穩(wen)定性越來越高(gao),PLC專屬(shu)通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)網絡系統初步建立,通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)接口的(de)存在也使得PLC電(dian)力(li)拖動一體(ti)化(hua)通(tong)(tong)(tong)信(xin)(xin)(xin)(xin)(xin)功能的(de)實(shi)現更為便捷。
2.3運(yun)行控制
將PLC技術應用于電(dian)(dian)力(li)拖(tuo)(tuo)動(dong)(dong)一體(ti)(ti)化(hua)控(kong)制(zhi)(zhi)系統(tong)中(zhong)可(ke)以提高(gao)對(dui)相(xiang)關設備(bei)(bei)運行控(kong)制(zhi)(zhi)的(de)(de)(de)(de)成效,生(sheng)產(chan)設備(bei)(bei)在接受到可(ke)編程邏輯控(kong)制(zhi)(zhi)器(qi)的(de)(de)(de)(de)指令(ling)后會作出指定的(de)(de)(de)(de)動(dong)(dong)作和(he)狀態,控(kong)制(zhi)(zhi)的(de)(de)(de)(de)效率(lv)顯著提升(sheng),于此同時控(kong)制(zhi)(zhi)功能的(de)(de)(de)(de)實(shi)現(xian)方式更加(jia)多樣化(hua),與生(sheng)產(chan)系統(tong)的(de)(de)(de)(de)聯系也(ye)更為(wei)緊密。電(dian)(dian)力(li)拖(tuo)(tuo)動(dong)(dong)一體(ti)(ti)化(hua)中(zhong)PLC運行控(kong)制(zhi)(zhi)的(de)(de)(de)(de)功能主(zhu)要表現(xian)在對(dui)機器(qi)人(ren)、電(dian)(dian)梯(ti)等相(xiang)關設備(bei)(bei)的(de)(de)(de)(de)控(kong)制(zhi)(zhi)上,相(xiang)關設備(bei)(bei)收到控(kong)制(zhi)(zhi)器(qi)的(de)(de)(de)(de)指令(ling)后通過物(wu)理運動(dong)(dong)促進(jin)系統(tong)工作的(de)(de)(de)(de)順利進(jin)行。與傳統(tong)的(de)(de)(de)(de)繼電(dian)(dian)器(qi)等控(kong)制(zhi)(zhi)器(qi)相(xiang)比PLC的(de)(de)(de)(de)穩定性也(ye)更強,不(bu)(bu)容易受到環境或者是其他訊(xun)號的(de)(de)(de)(de)干擾,因(yin)而磁場條(tiao)件不(bu)(bu)穩定的(de)(de)(de)(de)電(dian)(dian)力(li)拖(tuo)(tuo)動(dong)(dong)一體(ti)(ti)化(hua)實(shi)行環境之下PLC擁(yong)有較高(gao)的(de)(de)(de)(de)實(shi)用性,相(xiang)關電(dian)(dian)力(li)設備(bei)(bei)自(zi)動(dong)(dong)化(hua)水平和(he)安全性都(dou)會有所提升(sheng)。
2.4開關量邏輯控制
開(kai)關量邏(luo)輯(ji)控(kong)(kong)(kong)制(zhi)(zhi)是(shi)PLC技術(shu)的(de)(de)(de)(de)基(ji)礎(chu)功能(neng)之一,當電(dian)(dian)力(li)拖動一體化(hua)系統(tong)出(chu)(chu)現(xian)異常(chang)現(xian)象或者(zhe)是(shi)運行故障時(shi),PLC可以(yi)輔(fu)助(zhu)機(ji)電(dian)(dian)控(kong)(kong)(kong)制(zhi)(zhi)系統(tong),對原有控(kong)(kong)(kong)制(zhi)(zhi)系統(tong)的(de)(de)(de)(de)邏(luo)輯(ji)功能(neng)進(jin)(jin)行復制(zhi)(zhi),模擬出(chu)(chu)相應的(de)(de)(de)(de)程(cheng)(cheng)序代(dai)替其正常(chang)進(jin)(jin)行工作(zuo),避免(mian)控(kong)(kong)(kong)制(zhi)(zhi)器(qi)的(de)(de)(de)(de)故障阻礙生(sheng)產的(de)(de)(de)(de)順利進(jin)(jin)行,可編(bian)程(cheng)(cheng)邏(luo)輯(ji)控(kong)(kong)(kong)制(zhi)(zhi)可以(yi)對繼電(dian)(dian)器(qi)的(de)(de)(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)程(cheng)(cheng)序和邏(luo)輯(ji)功能(neng)進(jin)(jin)行模式(shi)實現(xian)對電(dian)(dian)氣機(ji)床以(yi)及沖床等設備的(de)(de)(de)(de)控(kong)(kong)(kong)制(zhi)(zhi),程(cheng)(cheng)序模擬也是(shi)PLC技術(shu)的(de)(de)(de)(de)突出(chu)(chu)優(you)勢(shi)。PLC可以(yi)代(dai)替傳統(tong)的(de)(de)(de)(de)電(dian)(dian)磁(ci)(ci)繼電(dian)(dian)器(qi),簡化(hua)了電(dian)(dian)磁(ci)(ci)元件之間的(de)(de)(de)(de)接線,降低了檢(jian)修和維(wei)護的(de)(de)(de)(de)難(nan)度(du)。PLC根據(ju)實際的(de)(de)(de)(de)工作(zuo)狀態以(yi)分閘操作(zuo)顯(xian)示指示信號,開(kai)關數量得以(yi)減少,電(dian)(dian)路(lu)控(kong)(kong)(kong)制(zhi)(zhi)的(de)(de)(de)(de)復雜性隨之降低,電(dian)(dian)力(li)拖動一體化(hua)的(de)(de)(de)(de)自動化(hua)能(neng)力(li)顯(xian)著(zhu)提高。
2.5安(an)全回路
PLC安(an)全回路功能可(ke)以對電(dian)(dian)力拖動(dong)系統(tong)泵類(lei)設(she)備的(de)安(an)全進行(xing)保障(zhang),提高電(dian)(dian)力拖動(dong)一體(ti)化泵類(lei)設(she)備的(de)自動(dong)化控(kong)制(zhi)(zhi)成效(xiao),并將控(kong)制(zhi)(zhi)的(de)具體(ti)執行(xing)方式與泵類(lei)的(de)運行(xing)特點和(he)運行(xing)時間想(xiang)適應(ying)。目(mu)前電(dian)(dian)力拖動(dong)一體(ti)化中(zhong)的(de)泵類(lei)控(kong)制(zhi)(zhi)往往是由PLC控(kong)制(zhi)(zhi)和(he)常(chang)規控(kong)制(zhi)(zhi)手段共同配合的(de),以此來(lai)保證(zheng)系統(tong)運行(xing)的(de)可(ke)靠性。
3 結束語
綜上所述(shu),可編程邏輯控制器應用于(yu)(yu)電力拖動一體(ti)化可以提(ti)高生(sheng)產控制系統(tong)的(de)適應性,滿足(zu)不同(tong)(tong)的(de)生(sheng)產技(ji)術和工(gong)藝(yi)流(liu)程的(de)需求,提(ti)高工(gong)業生(sheng)產電力拖動控制線路的(de)安全性和穩定性。于(yu)(yu)此同(tong)(tong)時PLC技(ji)術也(ye)日漸成熟,投(tou)入成本也(ye)逐(zhu)漸降低,有利于(yu)(yu)促進相關(guan)企業經濟效(xiao)益和控制成效(xiao)的(de)雙重提(ti)升。