目(mu)前，我(wo)國電(dian)(dian)(dian)(dian)(dian)(dian)力系(xi)(xi)(xi)統的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)源中性(xing)點一般是(shi)不直(zhi)接接地(di)(di)的(de)(de)，所以當線(xian)路(lu)單相(xiang)接地(di)(di)時流(liu)過故障(zhang)(zhang)點的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)實(shi)際是(shi)線(xian)路(lu)對地(di)(di)電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)產生的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)。據(ju)統計，電(dian)(dian)(dian)(dian)(dian)(dian)力系(xi)(xi)(xi)統的(de)(de)故障(zhang)(zhang)很大程度是(shi)由于線(xian)路(lu)單相(xiang)接地(di)(di)時電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)過大導致(zhi)起弧(hu)(hu)(hu)且電(dian)(dian)(dian)(dian)(dian)(dian)弧(hu)(hu)(hu)無法自行熄弧(hu)(hu)(hu)引起的(de)(de)。因此，我(wo)國的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)力規(gui)程規(gui)定(ding)(ding)當10kV和(he)35kV系(xi)(xi)(xi)統電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)分別(bie)大于30A和(he)10A時，應裝設(she)消弧(hu)(hu)(hu)線(xian)圈(quan)以補(bu)償電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)，這就(jiu)要求對其電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)進行測(ce)量(liang)以做決定(ding)(ding)。另外(wai)，電(dian)(dian)(dian)(dian)(dian)(dian)力系(xi)(xi)(xi)統的(de)(de)對地(di)(di)電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)和(he)PT的(de)(de)參(can)數配合會產生PT鐵(tie)磁(ci)諧(xie)振過電(dian)(dian)(dian)(dian)(dian)(dian)壓，為了驗(yan)證該配電(dian)(dian)(dian)(dian)(dian)(dian)系(xi)(xi)(xi)統是(shi)否會發(fa)生PT諧(xie)振及發(fa)生什(shen)么性(xing)質的(de)(de)諧(xie)振，也必須準確(que)測(ce)量(liang)電(dian)(dian)(dian)(dian)(dian)(dian)力系(xi)(xi)(xi)統的(de)(de)對地(di)(di)電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)值。

傳統的(de)(de)(de)測(ce)量(liang)(liang)(liang)電(dian)(dian)容(rong)電(dian)(dian)流(liu)的(de)(de)(de)方(fang)法有單相金屬接(jie)地的(de)(de)(de)直(zhi)接(jie)法、外(wai)加電(dian)(dian)容(rong)間接(jie)測(ce)量(liang)(liang)(liang)法等，這些方(fang)法都要接(jie)觸到一次(ci)設備，因而(er)存(cun)在(zai)試驗危(wei)險、操作(zuo)繁雜，工(gong)作(zuo)效(xiao)率低等缺(que)點。進(jin)而(er)出(chu)現了在(zai)PT二次(ci)側注入信號法測(ce)量(liang)(liang)(liang)電(dian)(dian)網電(dian)(dian)容(rong)電(dian)(dian)流(liu)；與(yu)傳統測(ce)量(liang)(liang)(liang)方(fang)法相比，該方(fang)法測(ce)量(liang)(liang)(liang)過(guo)程中，測(ce)試儀無需(xu)和一次(ci)側直(zhi)接(jie)相連(lian)，因而(er)試驗不(bu)存(cun)在(zai)危(wei)險性，無需(xu)做繁雜的(de)(de)(de)安全工(gong)作(zuo)和等待冗(rong)長的(de)(de)(de)調度命令，只需(xu)將測(ce)量(liang)(liang)(liang)線接(jie)于PT的(de)(de)(de)開口三角(jiao)端子就可(ke)以測(ce)量(liang)(liang)(liang)出(chu)電(dian)(dian)容(rong)電(dian)(dian)流(liu)的(de)(de)(de)數據。從PT開口三角(jiao)處注入的(de)(de)(de)是(shi)微弱的(de)(de)(de)異頻測(ce)試信號，所以既不(bu)會對繼(ji)電(dian)(dian)保護和PT本身(shen)產生(sheng)任何影響，又避開了50Hz的(de)(de)(de)工(gong)頻干擾信號。

但是，現有(you)的基于PT二次側(ce)注入(ru)信號法的測試儀體(ti)積(ji)及重量較(jiao)(jiao)大，便攜性較(jiao)(jiao)差(cha)不利于測試量較(jiao)(jiao)大的工況(kuang)。

為解決這些問題，我公司在上一(yi)(yi)代(dai)基于(yu)PT二次側注入(ru)信號法測試(shi)(shi)儀(yi)的基礎上，經過重新(xin)(xin)(xin)研發(fa)設計，開發(fa)出(chu)新(xin)(xin)(xin)一(yi)(yi)代(dai)手持(chi)式(shi)電容電流測試(shi)(shi)儀(yi)。采用(yong)全(quan)(quan)新(xin)(xin)(xin)硬件結(jie)構(gou)和(he)速度(du)更(geng)快的ARM處理器及AD轉換器，內置全(quan)(quan)新(xin)(xin)(xin)的全(quan)(quan)數字變(bian)頻(pin)逆變(bian)電源，將連個頻(pin)率的注入(ru)信號整合為一(yi)(yi)個波形，采樣(yang)后再通過傅(fu)里葉變(bian)換提取各個頻(pin)率的角度(du)與(yu)幅值，因此一(yi)(yi)次測試(shi)(shi)就可得出(chu)測量數據。提高了測試(shi)(shi)效率。與(yu)前一(yi)(yi)代(dai)相比，新(xin)(xin)(xin)一(yi)(yi)代(dai)體積和(he)重量都大(da)大(da)減小，更(geng)加便于(yu)攜帶(dai)和(he)現場測試(shi)(shi)。加入(ru)新(xin)(xin)(xin)的測量方法，以解決4PT連接方式(shi)電網電容電流測試(shi)(shi)精度(du)不高的問題。

該測試(shi)儀采用工業彩色液(ye)晶屏（強光下(xia)可讀）、中文菜單(dan)、人機交互更加友好，并(bing)且(qie)具(ju)備(bei)U盤(pan)存儲功能。接線簡(jian)單(dan)、測試(shi)速(su)度快、測試(shi)穩(wen)定性和數據準確(que)性高，大大減輕了(le)試(shi)驗(yan)人員的勞動強度，提(ti)高了(le)工作(zuo)效率。

測量范(fan)圍(wei)更(geng)(geng)寬，測試速度更(geng)(geng)快。

工業級七寸彩色(se)液晶顯示屏，分辨率800×480點陣，強光(guang)下可讀。

人(ren)機交互界(jie)面(mian)更加友好： 

具備多重零序過壓(ya)保護電路，測試儀輸出端可耐受AC100V 50HZ電壓(ya)而不損壞。

內置(zhi)全(quan)數(shu)字變(bian)頻(pin)逆變(bian)電(dian)源(yuan)，具有輸(shu)出(chu)(chu)頻(pin)率(lv)準確、輸(shu)出(chu)(chu)效(xiao)率(lv)高、發熱(re)量小(xiao)、體積小(xiao)、重量輕、長時間工作穩定等特點。

具備輸出短路保護功能。

內置熱敏打(da)印機，方便用(yong)戶現場打(da)印數(shu)據。

具備(bei)實時時鐘，可(ke)實時顯示當前(qian)時間和日期(qi)；測量結果(guo)包括(kuo)測量日期(qi)及時間。

測(ce)量數據存儲方式(shi)分為本機(ji)(ji)存儲和優(you)盤存儲，本機(ji)(ji)存儲可存儲測(ce)量數據200條。

便攜(xie)式、體積小、重量輕，方便攜(xie)帶使用(yong)。