【互感(gan)器(qi)的功能】互感(gan)器(qi)的作用(yong)(yong)是什么 互感(gan)器(qi)原(yuan)理及用(yong)(yong)途
互感器原理及用途
在供電用電的線路中,電流相差從幾安到幾萬安,電壓相差從幾伏到幾百萬伏。線路中電流電壓都比較高,如直接測量是非常危險的。為便于二次儀表測量需要轉換為比較統一的電流電壓,使用互感器起到變流變壓和電氣隔(ge)離的作用。
顯示儀表大部(bu)分是指針式(shi)的(de)電(dian)流電(dian)壓表,所以電(dian)流互感器的(de)二次電(dian)流大多(duo)數是安培級的(de)(如5等)。隨(sui)著時代發展(zhan),電量測(ce)量大多已經達到數字化,而(er)計算(suan)機的采樣的信號(hao)一般為(wei)毫安級(0-5V、4-20mA等)。微型電(dian)流(liu)(liu)互(hu)感(gan)(gan)(gan)器(qi)二(er)次電(dian)流(liu)(liu)為毫安級,主要起(qi)大互(hu)感(gan)(gan)(gan)器(qi)與采(cai)樣之(zhi)間的(de)橋(qiao)梁作用(yong)(yong)。微型電(dian)流(liu)(liu)互(hu)感(gan)(gan)(gan)器(qi)稱(cheng)之(zhi)為“儀(yi)用(yong)(yong)電(dian)流(liu)(liu)互(hu)感(gan)(gan)(gan)器(qi)”。(“儀(yi)用(yong)(yong)電(dian)流(liu)(liu)互(hu)感(gan)(gan)(gan)器(qi)”有一層含義是在(zai)實驗室使用(yong)(yong)的(de)多電(dian)流(liu)(liu)比(bi)精密電(dian)流(liu)(liu)互(hu)感(gan)(gan)(gan)器(qi),一般用(yong)(yong)于(yu)擴大儀(yi)表量程。)
電(dian)流互感(gan)器原理線路圖微(wei)型(xing)電(dian)流互感(gan)器與變(bian)壓(ya)(ya)器類(lei)似(si)也是(shi)(shi)根據(ju)電(dian)磁感(gan)應原理工作,變(bian)壓(ya)(ya)器變(bian)換的是(shi)(shi)電(dian)壓(ya)(ya)而微(wei)型(xing)電(dian)流互感(gan)器變(bian)換的是(shi)(shi)電(dian)流罷(ba)了。繞組N1接被測(ce)電流,稱為一次繞(rao)組(zu)(zu)(或原邊繞(rao)組(zu)(zu)、初級繞(rao)組(zu)(zu));繞(rao)組(zu)(zu)N2接測量儀表,稱為二(er)次(ci)繞(rao)組(zu)(或副邊繞(rao)組(zu)、次(ci)級繞(rao)組(zu))。
微型電(dian)(dian)流互(hu)感器一次(ci)繞組電(dian)(dian)流I1與二(er)次繞組I2的電(dian)流比,叫實際電(dian)流比K。微(wei)型電(dian)流(liu)互感(gan)器在(zai)額(e)定工(gong)作(zuo)電(dian)流(liu)下工(gong)作(zuo)時的電(dian)流(liu)比(bi)叫電(dian)流(liu)互感(gan)器額(e)定電(dian)流(liu)比(bi),用Kn表示。Kn=I1n/I2n。
互感器的作用是什么
電(dian)(dian)(dian)(dian)(dian)力(li)系(xi)統(tong)為了傳輸電(dian)(dian)(dian)(dian)(dian)能,往(wang)往(wang)采(cai)用(yong)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)、大電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)回(hui)路把電(dian)(dian)(dian)(dian)(dian)力(li)送往(wang)用(yong)戶,無法(fa)用(yong)儀表(biao)進(jin)行直接(jie)測(ce)(ce)量(liang)(liang)(liang)(liang)(liang)。互感器(qi)(qi)的(de)作用(yong),就是(shi)將(jiang)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)和(he)大電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)按比例(li)降(jiang)到可以(yi)用(yong)儀表(biao)直接(jie)測(ce)(ce)量(liang)(liang)(liang)(liang)(liang)的(de)數值,便(bian)于儀表(biao)直接(jie)測(ce)(ce)量(liang)(liang)(liang)(liang)(liang),同時為繼電(dian)(dian)(dian)(dian)(dian)保護和(he)自動(dong)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)提供電(dian)(dian)(dian)(dian)(dian)源。電(dian)(dian)(dian)(dian)(dian)力(li)系(xi)統(tong)用(yong)互感器(qi)(qi)是(shi)將(jiang)電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)(wang)高電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)、大電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)信息傳遞到低電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)、小電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)二(er)次(ci)側的(de)計量(liang)(liang)(liang)(liang)(liang)、測(ce)(ce)量(liang)(liang)(liang)(liang)(liang)儀表(biao)及繼電(dian)(dian)(dian)(dian)(dian)保護、自動(dong)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)的(de)一種特殊變壓(ya)(ya)器(qi)(qi),是(shi)一次(ci)系(xi)統(tong)和(he)二(er)次(ci)系(xi)統(tong)的(de)聯絡(luo)元件,其(qi)一次(ci)繞組接(jie)入電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)(wang),二(er)次(ci)繞組分別與測(ce)(ce)量(liang)(liang)(liang)(liang)(liang)儀表(biao)、保護裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)等互相連接(jie)。互感器(qi)(qi)與測(ce)(ce)量(liang)(liang)(liang)(liang)(liang)儀表(biao)和(he)計量(liang)(liang)(liang)(liang)(liang)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)配合,可以(yi)測(ce)(ce)量(liang)(liang)(liang)(liang)(liang)一次(ci)系(xi)統(tong)的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)、電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)和(he)電(dian)(dian)(dian)(dian)(dian)能;與繼電(dian)(dian)(dian)(dian)(dian)保護和(he)自動(dong)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)配合,可以(yi)構成對(dui)電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)(wang)各(ge)種故障(zhang)的(de)電(dian)(dian)(dian)(dian)(dian)氣保護和(he)自動(dong)控制。互感器(qi)(qi)性(xing)能的(de)好(hao)壞,直接(jie)影(ying)響(xiang)到電(dian)(dian)(dian)(dian)(dian)力(li)系(xi)統(tong)測(ce)(ce)量(liang)(liang)(liang)(liang)(liang)、計量(liang)(liang)(liang)(liang)(liang)的(de)準(zhun)確性(xing)和(he)繼電(dian)(dian)(dian)(dian)(dian)器(qi)(qi)保護裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)動(dong)作的(de)可靠性(xing)。
互感器包括電壓互感器和電流互感器
電壓互感器是一種電壓變換裝置,有電壓變換和隔離兩重作用,它將高壓回路或低壓回路的高電壓轉變為低電壓(一般為100V),供給儀表(biao)和(he)繼(ji)電保護(hu)裝置實現測量、計量、保護(hu)等作用。
電(dian)(dian)流互(hu)感器是一(yi)種電(dian)(dian)流變換裝置,有(you)電(dian)(dian)流變換和隔離兩重作用,它將(jiang)高壓回(hui)路或低(di)壓回(hui)路的大電(dian)(dian)流轉變為(wei)低(di)壓小電(dian)(dian)流(一(yi)般為(wei)5A),供給儀表和繼電(dian)保護(hu)裝(zhuang)置(zhi)實現測量(liang)、計量(liang)、保護(hu)等(deng)作用。
實際(ji)測量時,為了更好的與儀表量程匹配,也有將5A以下(xia)小電流變換為(wei)大電流(5A)的(de)互感(gan)器。