300KV高頻直流高壓發生器操作步驟
1.1、使用(yong)前準備
※ 如做容性負載試驗時，應(ying)接入(ru)限流電(dian)阻
1.1.1 在使(shi)用前應檢查連接(jie)電纜不(bu)應有(you)斷路和短路現(xian)象(xiang)，倍壓筒不(bu)應有(you)凝(ning)露(lu)現(xian)象(xiang)，設備(bei)無破裂(lie)等損壞。
1.1.2 將控制箱與倍壓(ya)筒(tong)用(yong)五芯連(lian)接(jie)(jie)(jie)電纜連(lian)接(jie)(jie)(jie)好(hao)，倍壓(ya)筒(tong)和控制箱必須保持(chi)足夠距離。保護接(jie)(jie)(jie)地(di)(di)線(xian)與工作接(jie)(jie)(jie)地(di)(di)線(xian)以及放電棒的(de)接(jie)(jie)(jie)地(di)(di)線(xian)均(jun)應單獨(du)接(jie)(jie)(jie)到試(shi)品的(de)地(di)(di)線(xian)上(即一點接(jie)(jie)(jie)地(di)(di))。嚴禁(jin)各接(jie)(jie)(jie)地(di)(di)線(xian)相(xiang)互(hu)串聯，為(wei)此，應使用(yong)DHV專(zhuan)用(yong)接(jie)(jie)(jie)地(di)(di)線(xian)。
1.1.3 電源開關置(zhi)于關斷(duan)位(wei)置(zhi)并將調壓電位(wei)器(qi)回至零位(wei)。過電壓保護整(zheng)定值設定為試驗(yan)電壓的1.1倍。
1.2、空載升壓(ya)(ya)驗(yan)證(zheng)過電(dian)壓(ya)(ya)保護整定
1.2.1 接(jie)通(tong)電源開(kai)關(guan)，此時高壓斷紅燈亮，表示電源接(jie)通(tong)。
1.2.2 按下(xia)高壓通綠色按鈕，則綠燈亮，表示高壓接通。
1.2.3 順時(shi)針(zhen)方(fang)向平(ping)緩調(diao)節調(diao)壓(ya)(ya)電(dian)(dian)位(wei)器，輸出端即從零開始升壓(ya)(ya)，升至所(suo)需電(dian)(dian)壓(ya)(ya)后(hou)，按規(gui)定時(shi)間記錄電(dian)(dian)流表讀數，并檢(jian)查(cha)控制(zhi)箱(xiang)及高壓(ya)(ya)輸出線(xian)有(you)無異常現象(xiang)及聲(sheng)響(xiang)。必要時(shi)用外接高壓(ya)(ya)分(fen)壓(ya)(ya)器校準控制(zhi)箱(xiang)上的電(dian)(dian)壓(ya)(ya)表頭。
1.2.4 降壓，將調壓電位器回零(ling)后(hou)，隨即按(an)高壓斷(duan)紅色按(an)鈕(niu)，切斷(duan)高壓并關閉(bi)電源(yuan)開(kai)關。
1.3、對試(shi)品進(jin)行(xing)泄漏及直流耐壓試(shi)驗
1.3.1 在進行1.1-1.2檢查試驗(yan)確認直流高壓發生器無(wu)異常情況后(hou)，即(ji)可(ke)開始(shi)進行試品的泄漏及直流耐壓試驗(yan)。將試品、地線等連接好(hao)，檢查無(wu)誤后(hou)即(ji)打開電源。
1.3.2 根據(ju)步驟1.2.1-1.2.3升壓(ya)至所需電壓(ya)或電流。
升(sheng)壓(ya)速度以每秒3～5kV試驗(yan)電(dian)(dian)壓(ya)為宜。對(dui)于(yu)大電(dian)(dian)容試品升(sheng)壓(ya)時還需監視(shi)電(dian)(dian)流表充電(dian)(dian)電(dian)(dian)流不(bu)超過額(e)定(ding)的最大充電(dian)(dian)電(dian)(dian)流。
對小(xiao)電(dian)(dian)(dian)容(rong)試品如(ru)氧(yang)化鋅避雷器(qi)、磁(ci)吹避雷器(qi)等，先(xian)升(sheng)(sheng)(sheng)至(zhi)所(suo)需電(dian)(dian)(dian)壓(ya)(電(dian)(dian)(dian)流(liu))的(de)95％左右，再緩慢升(sheng)(sheng)(sheng)壓(ya)至(zhi)所(suo)需的(de)電(dian)(dian)(dian)壓(ya)(電(dian)(dian)(dian)流(liu))，從數顯表上讀出電(dian)(dian)(dian)壓(ya)(電(dian)(dian)(dian)流(liu))值(zhi)。如(ru)需對氧(yang)化鋅避雷器(qi)進(jin)行泄(xie)(xie)漏值(zhi)測(ce)量時(shi)(shi)，先(xian)升(sheng)(sheng)(sheng)壓(ya)至(zhi)電(dian)(dian)(dian)流(liu)為1mA時(shi)(shi)的(de)電(dian)(dian)(dian)壓(ya)值(zhi)，然后(hou)按(an)(an)(an)下0.75倍(bei)黃色(se)按(an)(an)(an)鈕，此時(shi)(shi)電(dian)(dian)(dian)壓(ya)降至(zhi)原來(lai)的(de)0.75倍(bei)，并在一(yi)分鐘(zhong)內保持此狀態。此時(shi)(shi)可(ke)讀取泄(xie)(xie)漏電(dian)(dian)(dian)流(liu)值(zhi)（uA）。測(ce)量完(wan)畢后(hou)，調壓(ya)電(dian)(dian)(dian)位(wei)器(qi)逆時(shi)(shi)針回到(dao)零，按(an)(an)(an)下高(gao)壓(ya)斷紅色(se)按(an)(an)(an)鈕，如(ru)需再次升(sheng)(sheng)(sheng)壓(ya)時(shi)(shi)按(an)(an)(an)高(gao)壓(ya)通綠色(se)按(an)(an)(an)鈕即可(ke)。
1.3.3 試驗完(wan)畢(bi)，根據(ju)步驟1.2.4降壓。
※ 必(bi)要時(shi)用外(wai)接(jie)高壓(ya)分(fen)壓(ya)器比對控制箱(xiang)上的電壓(ya)。
1.4、幾種測量方法
1.4.1 一般測量時，當接好線后，先將直流高壓發生器連(lian)接(jie)試(shi)品(pin)(pin)的(de)(de)線懸空(kong)，升壓至(zhi)試(shi)驗電(dian)壓后，記錄空(kong)載試(shi)驗時的(de)(de)電(dian)暈和(he)雜散電(dian)流(liu)I1，然后接(jie)上(shang)試(shi)品(pin)(pin)連(lian)接(jie)線，升壓至(zhi)試(shi)驗電(dian)壓后，讀取總電(dian)流(liu)I2,得到試(shi)品(pin)(pin)的(de)(de)泄漏電(dian)流(liu)為Io=I2-I1。
1.4.2 當(dang)需要精確測量被試品(pin)泄漏電流時(shi)，則應(ying)在(zai)高壓側(ce)串入高壓微(wei)安表，如圖(tu)5所示。
圖(tu)5 微安表接(jie)(jie)入試品CX高壓側接(jie)(jie)線圖(tu)
微安表(biao)必須(xu)有(you)金屬屏蔽(bi)，應采用屏蔽(bi)線(xian)與試(shi)品連接。高壓引(yin)線(xian)的(de)屏蔽(bi)引(yin)出應與儀表(biao)端(duan)的(de)屏蔽(bi)緊密(mi)連接。如果試(shi)品表(biao)面(mian)污穢要排(pai)除試(shi)品表(biao)面(mian)泄漏電流的(de)影響，可在試(shi)品高電位端(duan)用裸金屬軟(ruan)線(xian)緊密(mi)繞幾圈后與高壓引(yin)線(xian)的(de)屏蔽(bi)層(ceng)相連接，如圖6所示。
1.4.3對氧(yang)化鋅、磁吹避(bi)雷器等試(shi)品(pin)(pin)接地(di)端(duan)可(ke)拆開的(de)情況下(xia)，也可(ke)采用在試(shi)品(pin)(pin)的(de)底部(地(di)電位(wei)(wei)側)串入電流(liu)表進行測量的(de)方(fang)式，如(ru)圖7所示。當要排(pai)除試(shi)品(pin)(pin)表面泄漏(lou)電流(liu)的(de)影響，可(ke)用軟的(de)裸銅線(xian)在試(shi)品(pin)(pin)地(di)電位(wei)(wei)端(duan)繞上(shang)幾圈(quan)并與(yu)屏(ping)蔽線(xian)的(de)屏(ping)蔽層相連接，如(ru)圖8所示。
1.4.4 對于氧化鋅避(bi)雷器等小電(dian)(dian)(dian)容試(shi)品(pin)(pin)，試(shi)驗(yan)(yan)(yan)完(wan)后(hou)一般通過(guo)機內測壓電(dian)(dian)(dian)阻(zu)放電(dian)(dian)(dian)，時間很快。而對電(dian)(dian)(dian)纜(lan)等大電(dian)(dian)(dian)容試(shi)品(pin)(pin)，試(shi)驗(yan)(yan)(yan)完(wan)后(hou)一般要待試(shi)品(pin)(pin)電(dian)(dian)(dian)壓自放電(dian)(dian)(dian)至試(shi)驗(yan)(yan)(yan)電(dian)(dian)(dian)壓的20％以下，再通過(guo)配套的放電(dian)(dian)(dian)棒進(jin)行(xing)放電(dian)(dian)(dian)，待試(shi)品(pin)(pin)充(chong)分(fen)放電(dian)(dian)(dian)后(hou)掛好接地(di)線，才允許進(jin)行(xing)高壓引線的拆除(chu)和更(geng)換接線的工作。
1.5、保護動(dong)作后的操作
在使用過程中(zhong)發現高(gao)壓(ya)(ya)通綠燈滅，高(gao)壓(ya)(ya)斷紅燈亮，電(dian)(dian)(dian)壓(ya)(ya)下降的現象，即為保(bao)護(hu)動作。此時應關閉電(dian)(dian)(dian)源開關，面板指示(shi)燈均不亮，將調(diao)壓(ya)(ya)電(dian)(dian)(dian)位器退回零位，一分鐘后(hou)(hou)待機(ji)內低(di)壓(ya)(ya)電(dian)(dian)(dian)容器充(chong)分放電(dian)(dian)(dian)，查明(ming)情況后(hou)(hou)，才允許再次(ci)打開電(dian)(dian)(dian)源開關，重新進行試驗。
