唐山光熱發電了解到的標準規定，交流輸出側過電壓/欠電壓保護范圍是額定電壓的85%到110%，當超過這個標準時，逆變器要停止運行。單相并網的額定電壓是230V，當電網電壓低于195.5V或者高于253V時，逆變器原則上要停機;三相并網的電壓是400V，當電網電壓低于340V或者高于440V時，逆變器原則上要停機。1以下兩種情況電網電壓會偏高，一是靠近降壓變壓器的地方，為了保證離變壓器較遠的地方電壓正常，考慮到線路電壓損耗，一般都會將變壓器輸出電壓拉高;二是光伏發電用(yong)(yong)戶側(ce)無法消化，輸(shu)送(song)到較遠的地方要提高電壓(ya)，造成逆(ni)(ni)(ni)變器(qi)輸(shu)出側(ce)電壓(ya)過高，引起(qi)逆(ni)(ni)(ni)變器(qi)保護關機。這(zhe)時有(you)三種(zhong)方法可(ke)以讓逆(ni)(ni)(ni)變器(qi)繼續運行：一是(shi)(shi)加大輸(shu)出電纜線徑，因為電纜越(yue)(yue)(yue)粗，阻(zu)抗越(yue)(yue)(yue)低;二是(shi)(shi)移動逆(ni)(ni)(ni)變器(qi)靠近并網點，電纜越(yue)(yue)(yue)短，阻(zu)抗越(yue)(yue)(yue)低;三是(shi)(shi)手動調整(zheng)逆(ni)(ni)(ni)變器(qi)電壓(ya)范(fan)圍，但不能(neng)(neng)調得太高，超(chao)過270V有(you)可(ke)能(neng)(neng)損壞(huai)用(yong)(yong)戶其它用(yong)(yong)電設(she)備。2逆(ni)(ni)(ni)變器(qi)交流線如(ru)果接(jie)錯，也有(you)可(ke)能(neng)(neng)導致逆(ni)(ni)(ni)變器(qi)報“交流電壓(ya)超(chao)范(fan)圍”故障。

　　光伏并網逆變(bian)器報“交流(liu)電(dian)(dian)(dian)壓(ya)(ya)超范圍”，是很常見的(de)一種故障，因為電(dian)(dian)(dian)網的(de)電(dian)(dian)(dian)壓(ya)(ya)不(bu)是恒定不(bu)變(bian)的(de)，會 隨著(zhu)負載和(he)潮流(liu)的(de)變(bian)化(hua)(hua)而(er)變(bian)化(hua)(hua)，而(er)逆變(bian)器的(de)輸出電(dian)(dian)(dian)壓(ya)(ya)跟隨電(dian)(dian)(dian)網電(dian)(dian)(dian)壓(ya)(ya)，在電(dian)(dian)(dian)網異(yi)常時，需要逆變(bian)器停止供(gong)電(dian)(dian)(dian)，以免對電(dian)(dian)(dian)網造(zao)成(cheng)更大的(de)傷害。

　　如(ru)(ru)何(he)檢(jian)測交(jiao)流電(dian)(dian)(dian)(dian)壓(ya)故障(zhang)，先用(yong)(yong)萬用(yong)(yong)表(biao)檢(jian)測電(dian)(dian)(dian)(dian)網電(dian)(dian)(dian)(dian)壓(ya)，如(ru)(ru)果電(dian)(dian)(dian)(dian)壓(ya)不正(zheng)常(chang)，說(shuo)(shuo)明是電(dian)(dian)(dian)(dian)網的問(wen)(wen)題(ti)(ti);第(di)二步，檢(jian)測交(jiao)流開(kai)(kai)關(guan)(guan)，正(zheng)常(chang)閉合狀態下，開(kai)(kai)關(guan)(guan)上下導通，進線(xian)和出(chu)(chu)線(xian)之間是沒有電(dian)(dian)(dian)(dian)壓(ya)的，如(ru)(ru)果電(dian)(dian)(dian)(dian)壓(ya)大(da)于(yu)5V，說(shuo)(shuo)明開(kai)(kai)關(guan)(guan)有問(wen)(wen)題(ti)(ti);第(di)三步，如(ru)(ru)果交(jiao)流開(kai)(kai)關(guan)(guan)沒問(wen)(wen)題(ti)(ti)，檢(jian)測逆(ni)(ni)變器(qi)(qi)(qi)的交(jiao)流輸出(chu)(chu)接(jie)線(xian)端子，用(yong)(yong)萬用(yong)(yong)表(biao)檢(jian)測接(jie)線(xian)端子相線(xian)之間的電(dian)(dian)(dian)(dian)壓(ya)，要用(yong)(yong)電(dian)(dian)(dian)(dian)網的電(dian)(dian)(dian)(dian)壓(ya)一致，如(ru)(ru)果不一致，可能是從開(kai)(kai)關(guan)(guan)到逆(ni)(ni)變器(qi)(qi)(qi)這一段電(dian)(dian)(dian)(dian)纜有問(wen)(wen)題(ti)(ti)，或者逆(ni)(ni)變器(qi)(qi)(qi)輸出(chu)(chu)端子有問(wen)(wen)題(ti)(ti);第(di)四步，如(ru)(ru)果交(jiao)流輸出(chu)(chu)接(jie)線(xian)端子測得(de)的電(dian)(dian)(dian)(dian)壓(ya)正(zheng)常(chang)，逆(ni)(ni)變器(qi)(qi)(qi)還報交(jiao)流電(dian)(dian)(dian)(dian)壓(ya)故障(zhang)，則可能是逆(ni)(ni)變器(qi)(qi)(qi)內(nei)部采樣(yang)問(wen)(wen)題(ti)(ti)。

　　相(xiang)(xiang)線(xian)和(he)零(ling)線(xian)接錯(cuo)，逆(ni)變(bian)器A相(xiang)(xiang)會(hui)顯示(shi)是線(xian)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)380V，B，C會(hui)顯示(shi)是相(xiang)(xiang)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)220V，逆(ni)變(bian)器認(ren)為(wei)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)過(guo)低(di)而不(bu)啟動(dong)。這種(zhong)情況(kuang)都是發生在逆(ni)變(bian)器安裝階段。上圖是逆(ni)變(bian)器報交(jiao)流(liu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)超范(fan)圍警告，從(cong)APP監控(kong)上看到的(de)電(dian)(dian)(dian)(dian)(dian)網(wang)各相(xiang)(xiang)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，其中AC1正(zheng)常，AC2和(he)AC3電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)偏低(di)，經現場檢測，是相(xiang)(xiang)線(xian)L1和(he)零(ling)線(xian)N線(xian)接反，把L1相(xiang)(xiang)線(xian)和(he)零(ling)線(xian)N線(xian)對調換，逆(ni)變(bian)器恢(hui)復正(zheng)常。3交(jiao)流(liu)開(kai)關(guan)(guan)接觸不(bu)良或(huo)者(zhe)(zhe)損壞，也會(hui)導(dao)致(zhi)逆(ni)變(bian)器報“交(jiao)流(liu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)超范(fan)圍”故障。逆(ni)變(bian)器后的(de)交(jiao)流(liu)開(kai)關(guan)(guan)，由于長時間(jian)運行，如果電(dian)(dian)(dian)(dian)(dian)纜(lan)線(xian)頭沒有(you)壓(ya)(ya)(ya)緊，或(huo)者(zhe)(zhe)開(kai)關(guan)(guan)質量(liang)(liang)不(bu)好，觸點就會(hui)出現比(bi)(bi)較(jiao)大的(de)內阻，有(you)可(ke)能導(dao)致(zhi)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)下降。上圖是一(yi)個電(dian)(dian)(dian)(dian)(dian)站報交(jiao)流(liu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)超范(fan)圍警告，從(cong)APP監控(kong)上看到的(de)電(dian)(dian)(dian)(dian)(dian)網(wang)各相(xiang)(xiang)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，AC1是10.1V，AC2是126.2V，AC3是128.9V，現場測量(liang)(liang)電(dian)(dian)(dian)(dian)(dian)網(wang)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)正(zheng)常，開(kai)關(guan)(guan)也沒有(you)斷開(kai)，只是開(kai)關(guan)(guan)溫(wen)度比(bi)(bi)較(jiao)高，拆開(kai)電(dian)(dian)(dian)(dian)(dian)纜(lan)接線(xian)端子(zi)，發現接觸點變(bian)黑。重新更新電(dian)(dian)(dian)(dian)(dian)纜(lan)接頭和(he)開(kai)關(guan)(guan)后，電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)恢(hui)復正(zheng)常，逆(ni)變(bian)器也可(ke)運行。