品牌 | 旭明 | 執行質量標準 | 國標 |
---|---|---|---|
產地 | 國產 | 加工定制 | 是 |
1.溫升試驗變壓器類型基(ji)本介紹
電(dian)氣設(she)(she)備出廠(chang)、交接(jie)或(huo)大修(xiu)后,應(ying)當進(jin)行(xing)交流耐壓(ya)試驗(yan),實際考(kao)核設(she)(she)備絕緣承(cheng)受過(guo)電(dian)壓(ya)的(de)絕緣水平(ping)。所以(yi)無論在制(zhi)造部(bu)門、運行(xing)部(bu)門的(de)高壓(ya)實驗(yan)室(shi)或(huo)試驗(yan)現場,應(ying)設(she)(she)有交流耐壓(ya)設(she)(she)備。
高壓(ya)(ya)試驗(yan)變(bian)(bian)壓(ya)(ya)器(qi)(qi)簡稱為(wei)試驗(yan)變(bian)(bian)壓(ya)(ya)器(qi)(qi)。試驗(yan)變(bian)(bian)壓(ya)(ya)器(qi)(qi)一(yi)般為(wei)升(sheng)壓(ya)(ya)變(bian)(bian)壓(ya)(ya)器(qi)(qi)。這種試驗(yan)變(bian)(bian)壓(ya)(ya)器(qi)(qi)利用其二次側所感(gan)應的工(gong)頻高電壓(ya)(ya),對各種電工(gong)產(chan)品和絕緣(yuan)材料(liao)等進行(xing)絕緣(yuan)性能試驗(yan)。
試(shi)(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)器(qi)(qi)是電機(ji)、變(bian)壓(ya)(ya)器(qi)(qi)、電器(qi)(qi)產品修(xiu)造(zao)中不(bu)可少的(de)一(yi)種耐壓(ya)(ya)試(shi)(shi)(shi)驗(yan)(yan)用(yong)電氣(qi)(qi)(qi)(qi)設備。試(shi)(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)特(te)點(dian)器(qi)(qi)主要用(yong)于電氣(qi)(qi)(qi)(qi)產品的(de)工頻(pin)耐壓(ya)(ya)試(shi)(shi)(shi)驗(yan)(yan)、局部放電測(ce)(ce)量、絕緣介質的(de)熱穩定試(shi)(shi)(shi)驗(yan)(yan)等;對(dui)中、高頻(pin)電氣(qi)(qi)(qi)(qi)設備還可采(cai)用(yong)特(te)殊頻(pin)率的(de)試(shi)(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)器(qi)(qi)進行(xing)耐壓(ya)(ya)試(shi)(shi)(shi)驗(yan)(yan)及(ji)有關電氣(qi)(qi)(qi)(qi)參數的(de)測(ce)(ce)量。
試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)一、二次(ci)繞組具有很大(da)的電(dian)壓(ya)(ya)(ya)比,一次(ci)電(dian)壓(ya)(ya)(ya)為0.4kV、3kV、6kV、10kV不等,二次(ci)電(dian)壓(ya)(ya)(ya)可制成100~2000kV或更(geng)高,容量可為3~9000kVA。對電(dian)力設(she)(she)(she)備(bei)現場試(shi)驗(yan),一般用輕型(xing)試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi);對6kV、10kV級變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)等電(dian)力設(she)(she)(she)備(bei)的耐(nai)壓(ya)(ya)(ya)試(shi)驗(yan)用50kV級升壓(ya)(ya)(ya)試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi);對35kV以(yi)上(shang)電(dian)壓(ya)(ya)(ya)等級的高壓(ya)(ya)(ya)、超高壓(ya)(ya)(ya)變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)等電(dian)力設(she)(she)(she)備(bei)的耐(nai)壓(ya)(ya)(ya)試(shi)驗(yan)用大(da)于被試(shi)設(she)(she)(she)備(bei)一次(ci)額定電(dian)壓(ya)(ya)(ya)5倍以(yi)上(shang)的超高壓(ya)(ya)(ya)試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi),如500kV、700kV、800kV級和一定容量級的升壓(ya)(ya)(ya)試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)。
試驗變壓器和電力變壓器的原理相同,所不同的是試驗變壓器的工作電壓高、使用時間短、溫升小,一般設有散熱器。另外,試驗變壓器的負載較小,且多為電容性負載。試驗變壓器的容量比電力變壓器的容量相對的要小。
2.溫升試驗變壓器類型特點
1)電(dian)壓(ya)(ya)高:試驗(yan)變(bian)壓(ya)(ya)器(qi)的一次(ci)(ci)電(dian)壓(ya)(ya)為220V或(huo)380V,但單臺(tai)試驗(yan)變(bian)壓(ya)(ya)器(qi)二次(ci)(ci)電(dian)壓(ya)(ya)則常達數千伏至數萬伏。二次(ci)(ci)電(dian)壓(ya)(ya)超(chao)過750kV的試驗(yan)變(bian)壓(ya)(ya)器(qi),通(tong)常采用多(duo)臺(tai)串級式結構。
2)電(dian)(dian)流(liu)小:試驗變壓(ya)器的額定電(dian)(dian)流(liu)實(shi)際上是被試品的電(dian)(dian)容電(dian)(dian)流(liu),所以一般小于1A。但用于電(dian)(dian)纜和大型電(dian)(dian)機試驗、外絕緣污穢試驗、線路(lu)電(dian)(dian)暈試驗等項目的試驗變壓(ya)器,二(er)次電(dian)(dian)流(liu)可達(da)數(shu)安。
3)工作時間短:因被試(shi)產品的耐壓時間短,所以試(shi)驗變壓器(qi)除了用于外絕緣污穢試(shi)驗、線路電(dian)暈試(shi)驗、電(dian)纜(lan)試(shi)驗外,一般均為0.5h或1h的短時工作制。
4)試驗變壓(ya)器一般為單相、戶(hu)(hu)內裝置(也有做成戶(hu)(hu)外裝置的(de)):均為油浸自冷式(shi)結構,繞組絕緣層較厚,高壓(ya)繞組通常一端接地。
5)試驗變(bian)壓器的(de)二次(ci)繞組首末端絕緣水平不(bu)同:首端為(wei)高(gao)電位,而末端直接(jie)接(jie)地(di)或通(tong)過電流表接(jie)地(di)。
6)設計和制造工藝要求高:由于工作電壓高,絕緣結構對試驗變壓器的整體尺寸有決定性的影響。器身一般要求真空干燥,100kV以上要求真空注油。
3.分類
1)從結構(gou)上分,有鐵殼式與絕緣外殼式試驗變壓器(qi)。
2)從(cong)電(dian)源(yuan)頻(pin)率(lv)(lv)上分,有工(gong)頻(pin)、倍頻(pin)、中頻(pin)及(ji)高頻(pin)幾種頻(pin)率(lv)(lv)級試(shi)驗(yan)變壓器。
3)按(an)電(dian)壓(ya)等級可分為低壓(ya)、高(gao)壓(ya)及超高(gao)壓(ya)試(shi)驗(yan)變壓(ya)器。
4)按使(shi)(shi)用形(xing)式(shi)(shi)可分(fen)為輕型移動(dong)式(shi)(shi)及固定式(shi)(shi);又(you)有單臺使(shi)(shi)用及兩臺或多臺串級(ji)使(shi)(shi)用試驗(yan)變(bian)壓器等。
試驗變壓(ya)器(qi)一般(ban)為單相(xiang)、戶(hu)內(nei)裝(zhuang)置(zhi),均為油浸自(zi)冷式(shi)結構(gou)。因為它的工(gong)作電(dian)壓(ya)高(gao),所以(yi)其繞組絕(jue)緣層較厚,而且高(gao)壓(ya)繞組一端(duan)接地。
試驗變壓器的具(ju)體結構(gou)型式,一般有單套管式、雙套管式及絕緣筒式三(san)種。
技術要(yao)求(qiu)
①輸(shu)出電壓(ya)(ya)(ya)波(bo)(bo)形。試驗變(bian)壓(ya)(ya)(ya)器(qi)輸(shu)出電壓(ya)(ya)(ya)波(bo)(bo)形應盡量(liang)接近正弦波(bo)(bo)。為了減少由(you)于空載電流的(de)諧(xie)波(bo)(bo)分量(liang)通(tong)過調壓(ya)(ya)(ya)器(qi)和變(bian)壓(ya)(ya)(ya)器(qi)的(de)阻(zu)抗(kang)后,產生諧(xie)波(bo)(bo)電壓(ya)(ya)(ya)而引起電壓(ya)(ya)(ya)波(bo)(bo)形畸(ji)變(bian),磁通(tong)密(mi)度應選在鐵心磁化曲線的(de)直線段;同時要選用(yong)波(bo)(bo)形畸(ji)變(bian)小的(de)調壓(ya)(ya)(ya)設(she)備,必要時可加設(she)濾波(bo)(bo)裝置。
②阻(zu)抗電(dian)(dian)壓(ya)(ya)。試(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)(qi)的(de)二(er)次電(dian)(dian)流(liu)一(yi)般為(wei)容(rong)性電(dian)(dian)流(liu),當二(er)次電(dian)(dian)流(liu)流(liu)經調(diao)壓(ya)(ya)器(qi)(qi)和試(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)(qi)的(de)阻(zu)抗時(shi)(shi),將導致輸(shu)出(chu)電(dian)(dian)壓(ya)(ya)超過由電(dian)(dian)壓(ya)(ya)比所確定的(de)數值,所以試(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)(qi)的(de)阻(zu)抗電(dian)(dian)壓(ya)(ya)不(bu)宜太大,否則可(ke)能(neng)影響測試(shi)(shi)結果的(de)準確性,同時(shi)(shi)還會降低試(shi)(shi)驗(yan)設備的(de)短路(lu)(lu)容(rong)量。但如(ru)阻(zu)抗電(dian)(dian)壓(ya)(ya)太小,被試(shi)(shi)品(pin)擊穿或閃絡(luo)時(shi)(shi),短路(lu)(lu)電(dian)(dian)流(liu)可(ke)能(neng)增大。單臺(tai)試(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)(qi)的(de)阻(zu)抗電(dian)(dian)壓(ya)(ya)一(yi)般為(wei)4.5~10%,組成(cheng)多臺(tai)串級時(shi)(shi),則可(ke)達30~40%。