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一般認為變(bian)壓(ya)(ya)器(qi)(qi)工作溫(wen)度是(shi)影響變(bian)壓(ya)(ya)器(qi)(qi)絕緣老化的(de)一個(ge)重要因(yin)素。石油紙絕緣變(bian)壓(ya)(ya)器(qi)(qi)工作溫(wen)度過高，會引起變(bian)壓(ya)(ya)器(qi)(qi)油及變(bian)壓(ya)(ya)器(qi)(qi)絕緣紙加(jia)速老化，影響變(bian)壓(ya)(ya)器(qi)(qi)的(de)使用壽命。所以在變(bian)壓(ya)(ya)器(qi)(qi)運行和維修工作中(zhong)，運行溫(wen)度是(shi)一個(ge)十分(fen)重要的(de)問題(ti)。
變壓器工作溫度(du)
油(you)(you)(you)(you)紙絕緣(yuan)(yuan)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)的工作溫(wen)(wen)度(du)，包括(kuo)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)油(you)(you)(you)(you)溫(wen)(wen)、變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)線(xian)圈(quan)(quan)溫(wen)(wen)度(du)。通常在(zai)箱體頂部(bu)(bu)(bu)安裝有測(ce)溫(wen)(wen)槽，可插入(ru)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)油(you)(you)(you)(you)內(nei)，并在(zai)其中(zhong)設置了溫(wen)(wen)度(du)傳感器(qi)(qi)(qi)來測(ce)量(liang)(liang)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)的油(you)(you)(you)(you)溫(wen)(wen)。因為(wei)被測(ce)對(dui)象是(shi)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)頂部(bu)(bu)(bu)的油(you)(you)(you)(you)，所以(yi)一(yi)般稱之為(wei)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)頂部(bu)(bu)(bu)油(you)(you)(you)(you)溫(wen)(wen)。因變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)繞組(zu)流過負載時會產生(sheng)熱(re)(re)(re)量(liang)(liang)，故運(yun)行中(zhong)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)線(xian)圈(quan)(quan)溫(wen)(wen)度(du)必須高于變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)油(you)(you)(you)(you)溫(wen)(wen)度(du)。在(zai)這(zhe)些溫(wen)(wen)度(du)變(bian)(bian)(bian)化中(zhong)，對(dui)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)絕緣(yuan)(yuan)老化影響最大的，就是(shi)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)內(nei)部(bu)(bu)(bu)最熱(re)(re)(re)點(dian)的溫(wen)(wen)度(du)，我們把它稱為(wei)熱(re)(re)(re)點(dian)溫(wen)(wen)度(du)。一(yi)般地(di)，變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)熱(re)(re)(re)點(dian)是(shi)在(zai)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)繞組(zu)靠近終(zhong)端的一(yi)處。因為(wei)不能準確(que)地(di)定位、準確(que)地(di)測(ce)量(liang)(liang)，通常采用(yong)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)繞組(zu)溫(wen)(wen)度(du)代替熱(re)(re)(re)溫(wen)(wen)，以(yi)監測(ce)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)內(nei)熱(re)(re)(re)點(dian)溫(wen)(wen)度(du)。所以(yi)在(zai)油(you)(you)(you)(you)紙絕緣(yuan)(yuan)變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)上通常會配置變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)頂層(ceng)油(you)(you)(you)(you)溫(wen)(wen)表和變(bian)(bian)(bian)壓(ya)(ya)器(qi)(qi)(qi)線(xian)圈(quan)(quan)溫(wen)(wen)度(du)計。
浙權（上海(hai)）電器(qi)(qi)設(she)(she)備制造(zao)有(you)限公(gong)司是一家(jia)集生(sheng)產(chan)、研發、銷(xiao)售為一體的專(zhuan)業(ye)性企業(ye)，本(ben)公(gong)司專(zhuan)業(ye)生(sheng)產(chan)變壓器(qi)(qi)、穩(wen)壓器(qi)(qi)、調壓器(qi)(qi)及(ji)低壓電器(qi)(qi)配套產(chan)品，始終“堅(jian)持(chi)企業(ye)創(chuang)新，追(zhui)求技術進步”是發展的一貫宗旨，公(gong)司擁有(you)雄厚的技術開發力量、優質的工藝檢測儀(yi)器(qi)(qi)和(he)生(sheng)產(chan)設(she)(she)備，積極引進國外的先進技術，不斷對產(chan)品加以改進和(he)完善，多年的專(zhuan)業(ye)化(hua)管理，已成功構建了(le)多層次的營銷(xiao)網絡。
可以(yi)認為變(bian)壓器繞組(zu)溫(wen)度是變(bian)壓器頂部油溫(wen)和繞組(zu)對(dui)油的(de)溫(wen)升的(de)疊加。通常(chang)在變(bian)壓器油溫(wen)檢測系統(tong)的(de)基礎上(shang)，添加變(bian)壓器負載電(dian)流，通過熱仿真(zhen)方法模擬了繞組(zu)中的(de)溫(wen)升，最終得出變(bian)壓器繞組(zu)溫(wen)度。該方法的(de)具體(ti)實現方式(shi)見下(xia)圖。
通過對(dui)變(bian)(bian)壓器(qi)(qi)頂(ding)層油溫升的測量，得(de)到了與負載電(dian)流(liu)成正比的電(dian)流(liu)Ip，變(bian)(bian)壓器(qi)(qi)外(wai)殼(ke)式電(dian)流(liu)互感器(qi)(qi)。該電(dian)流(liu)通過復(fu)合變(bian)(bian)送器(qi)(qi)中附(fu)有電(dian)熱元件(jian)，通過附(fu)加電(dian)流(liu)作用于電(dian)熱元件(jian)上所產生的額(e)外(wai)溫升，迭加在變(bian)(bian)壓器(qi)(qi)頂(ding)層油溫上，以求出(chu)繞組的溫度。
變壓器(qi)繞組(zu)溫度被忽略
因變壓(ya)器(qi)繞(rao)組(zu)溫度不(bu)能直接測量(liang)，且測量(liang)方法有一定誤差，故對(dui)變壓(ya)器(qi)繞(rao)組(zu)溫度的精確度不(bu)夠。與此同時，由(you)于對(dui)變壓(ya)器(qi)熱點溫度、線圈溫度知之甚少，導(dao)致變壓(ya)器(qi)繞(rao)組(zu)溫度在實際工作中被“冷(leng)落”。
第(di)一，某(mou)些操(cao)作規程對繞組溫(wen)(wen)度(du)(du)冷落(luo)。DL/T-572電(dian)(dian)力變(bian)壓(ya)器(qi)運行(xing)規范(fan)中規定了運行(xing)變(bian)壓(ya)器(qi)上油(you)溫(wen)(wen)、不(bu)表示繞組溫(wen)(wen)度(du)(du)。在編寫110(66)kV~500kV油(you)浸變(bian)壓(ya)器(qi)(電(dian)(dian)抗器(qi))操(cao)作規范(fan)時(shi)，"將繞組溫(wen)(wen)度(du)(du)視為(wei)間(jian)接(jie)測量，"相較(jiao)于(yu)油(you)面溫(wen)(wen)度(du)(du)誤(wu)差較(jiao)大，建議僅作參考(kao)。此(ci)建議無(wu)意間(jian)使變(bian)壓(ya)器(qi)繞組溫(wen)(wen)度(du)(du)處于(yu)可有可無(wu)的(de)位置。
在運檢過程中受到(dao)冷(leng)落，必然引起運檢工作(zuo)的(de)冷(leng)落。因此，巡檢時忽(hu)略了繞(rao)(rao)組(zu)(zu)溫(wen)度計(ji)(ji)的(de)讀數，檢修人(ren)員沒(mei)有及時處理繞(rao)(rao)組(zu)(zu)溫(wen)度計(ji)(ji)存在的(de)缺(que)陷，設(she)計(ji)(ji)人(ren)員從源頭上沒(mei)有考慮(lv)到(dao)對(dui)繞(rao)(rao)組(zu)(zu)溫(wen)度計(ji)(ji)進行(xing)補償所需的(de)電(dian)流互感器繞(rao)(rao)組(zu)(zu)，從而使繞(rao)(rao)組(zu)(zu)溫(wen)度表的(de)讀數便與(yu)油溫(wen)表一致。
變(bian)壓器繞(rao)組溫(wen)度必不可少
熱區(qu)溫(wen)(wen)(wen)度(du)(du)(du)是變壓器(qi)(qi)運(yun)行中十分重要的(de)參數，過(guo)高的(de)溫(wen)(wen)(wen)度(du)(du)(du)會加(jia)速其固態(tai)絕緣的(de)老(lao)化。因而變壓器(qi)(qi)負載(zai)導則(ze)規(gui)定(ding)非熱改性絕緣紙(zhi)在熱點溫(wen)(wen)(wen)度(du)(du)(du)98度(du)(du)(du)時(shi)的(de)相對老(lao)化速率為1；規(gui)定(ding)了(le)在正常循環負載(zai)條(tiao)件下(xia)過(guo)負荷(he)運(yun)行，熱區(qu)溫(wen)(wen)(wen)度(du)(du)(du)不(bu)得(de)超過(guo)120℃；規(gui)定(ding)了(le)長時(shi)間緊(jin)急(ji)處理負荷(he)時(shi)，熱點溫(wen)(wen)(wen)度(du)(du)(du)不(bu)得(de)超過(guo)140℃；規(gui)定(ding)了(le)緊(jin)急(ji)過(guo)載(zai)時(shi)的(de)熱點溫(wen)(wen)(wen)度(du)(du)(du)不(bu)得(de)超過(guo)160℃；所以，必須對繞(rao)組熱點溫(wen)(wen)(wen)度(du)(du)(du)加(jia)以重視。
有(you)人認為(wei)，由于繞(rao)組(zu)(zu)(zu)溫(wen)度(du)(du)是在最(zui)上層(ceng)油(you)(you)溫(wen)基(ji)礎上疊加的銅油(you)(you)溫(wen)差，則可通過(guo)監控(kong)(kong)上層(ceng)油(you)(you)溫(wen)的近似(si)方法間(jian)(jian)接監控(kong)(kong)變(bian)(bian)壓(ya)器繞(rao)組(zu)(zu)(zu)溫(wen)度(du)(du)。這里有(you)個問(wen)題(ti)要注意，就是變(bian)(bian)壓(ya)器繞(rao)組(zu)(zu)(zu)的時間(jian)(jian)常數，一般(ban)在4-10分(fen)(fen)鐘左右，而變(bian)(bian)壓(ya)器油(you)(you)的正常時間(jian)(jian)約為(wei)90-210分(fen)(fen)鐘。然后，當負載急劇變(bian)(bian)化(hua)時，變(bian)(bian)壓(ya)器油(you)(you)溫(wen)變(bian)(bian)化(hua)較慢(man)，線(xian)圈溫(wen)度(du)(du)變(bian)(bian)化(hua)較快。過(guo)載時，變(bian)(bian)壓(ya)器油(you)(you)溫(wen)未及時升高，而變(bian)(bian)壓(ya)器繞(rao)組(zu)(zu)(zu)溫(wen)度(du)(du)已升至極(ji)高，單獨監測上油(you)(you)溫(wen)將(jiang)延(yan)誤(wu)對變(bian)(bian)壓(ya)器負荷的調節和(he)冷卻系統投入，從(cong)而導致變(bian)(bian)壓(ya)器繞(rao)組(zu)(zu)(zu)溫(wen)度(du)(du)過(guo)高。
變(bian)壓器負載(zai)發生突變(bian)時，繞組(zu)溫(wen)(wen)度(du)和(he)頂部油溫(wen)(wen)發生變(bian)化趨勢。負荷系數(shu)(shu)(shu)從0.6升至1.2，負荷系數(shu)(shu)(shu)作了放(fang)大。結(jie)果表明，隨著(zhu)負載(zai)系數(shu)(shu)(shu)的(de)變(bian)化，繞組(zu)溫(wen)(wen)度(du)迅速上(shang)升，而最(zui)上(shang)層(ceng)油溫(wen)(wen)變(bian)化較(jiao)慢。
