電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)質量(liang)問題固然對UPS至關重要(yao)，但(dan)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器的(de)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)質量(liang)在(zai)(zai)(zai)很大程度上影響著電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)質量(liang)，其(qi)原因在(zai)(zai)(zai)前面(mian)已經(jing)提及。尤其(qi)是電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)精度一定要(yao)保證，因為(wei)浮(fu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)過(guo)(guo)高(gao)或過(guo)(guo)低都會影響電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)壽(shou)(shou)命(ming)(ming)，圖1表示的(de)是MSE電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)與壽(shou)(shou)命(ming)(ming)的(de)關系，該實驗是在(zai)(zai)(zai)40oC的(de)條(tiao)件下加速進行的(de)。由此曲線可(ke)以(yi)看(kan)出，在(zai)(zai)(zai)這里的(de)浮(fu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)推薦(jian)值是2.25V/cell，高(gao)于這個值或低于這個值都會縮(suo)(suo)短(duan)(duan)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)壽(shou)(shou)命(ming)(ming)。比(bi)如(ru)(ru)浮(fu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)是2.225V/cell時(shi)，壽(shou)(shou)命(ming)(ming)將縮(suo)(suo)短(duan)(duan)5%，而(er)浮(fu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)上升(sheng)到2.4V/cell時(shi)，壽(shou)(shou)命(ming)(ming)就縮(suo)(suo)短(duan)(duan)了40%。由此可(ke)見，維持精確(que)的(de)浮(fu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)值是如(ru)(ru)何重要(yao)。但(dan)為(wei)了使電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)長期使用(yong)后還能保證各電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)平衡，采用(yong)的(de)措施(shi)是均衡充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)，而(er)均衡充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)也大都是2.4V/cell，這就和上面(mian)的(de)曲線發生了矛盾，實際上事情就是這樣，有得就有失，所以(yi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)在(zai)(zai)(zai)均衡充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)時(shi)一定要(yao)控制好時(shi)間，以(yi)盡量(liang)延長電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)服務壽(shou)(shou)命(ming)(ming)。

　　圖1 MSE電池(chi)的充電電壓與壽命的關系（40oC加速實驗）

1.恒壓充電

　　所謂恒(heng)壓(ya)(ya)(ya)充電(dian)就(jiu)是用一穩壓(ya)(ya)(ya)源給電(dian)池(chi)充電(dian)，這種(zhong)方法簡單易(yi)行(xing)(xing)，也能夠保(bao)證電(dian)池(chi)的(de)(de)精確(que)浮充電(dian)壓(ya)(ya)(ya)。但若在電(dian)池(chi)深度放電(dian)后充電(dian)時，由于(yu)電(dian)池(chi)的(de)(de)內阻(zu)相對而(er)言仍然(ran)很低，就(jiu)會有很大的(de)(de)充電(dian)電(dian)流使化學反應(ying)劇烈地進(jin)行(xing)(xing)，從而(er)產生(sheng)大量的(de)(de)氣(qi)體(ti)，由于(yu)還原反應(ying)來不及(ji)進(jin)行(xing)(xing)，使殼內氣(qi)壓(ya)(ya)(ya)迅速增(zeng)加，沖開(kai)排氣(qi)閥(fa)將氣(qi)體(ti)逸出(chu)，加速了(le)電(dian)解液的(de)(de)干涸(he)，縮短(duan)了(le)電(dian)池(chi)的(de)(de)壽命(ming)；若排氣(qi)閥(fa)因故(gu)障而(er)無法打開(kai)，就(jiu)會使電(dian)池(chi)的(de)(de)外殼鼓脹(zhang)或破裂。隨著電(dian)池(chi)電(dian)壓(ya)(ya)(ya)的(de)(de)升(sheng)高，充電(dian)電(dian)流逐漸減小，其(qi)減小的(de)(de)規律是：

 　　                                             （1）

式中   ICH――電(dian)(dian)池的充電(dian)(dian)電(dian)(dian)流，A；

       E――充電(dian)器的輸出電(dian)壓，V；

       UGB――電池電壓，V；

       RGB――電池的內阻，Ω。

　　上式中有三個(ge)變(bian)量ICH、UGB、RGB，充電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)ICH隨著(zhu)充電(dian)(dian)(dian)過程的(de)進(jin)行而(er)(er)減小，電(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)壓UGB隨著(zhu)充電(dian)(dian)(dian)過程的(de)進(jin)行而(er)(er)升(sheng)高，而(er)(er)電(dian)(dian)(dian)池(chi)(chi)內阻RGB隨著(zhu)充電(dian)(dian)(dian)過程的(de)進(jin)行而(er)(er)減小。這(zhe)就決(jue)定了(le)充電(dian)(dian)(dian)過程的(de)非(fei)線(xian)性(xing)。尤其是在接近浮充電(dian)(dian)(dian)壓值時(shi)，使充電(dian)(dian)(dian)變(bian)的(de)非(fei)常緩慢，從理(li)論上講(jiang)，充電(dian)(dian)(dian)到(dao)額定浮充值的(de)時(shi)間是無窮大。

　　這種充(chong)電方式在早期的小容量UPS中(zhong)曾(ceng)一度使用(yong)過，因出現了(le)好多故障，目(mu)前一般不(bu)用(yong)了(le)。{{分頁}}

2.恒流充電

　　恒(heng)流充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)(de)好(hao)處在于(yu)：一(yi)方(fang)面可(ke)以限制充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流，避免(mian)了(le)(le)(le)由(you)于(yu)上述(shu)的(de)(de)(de)(de)劇烈(lie)反(fan)(fan)應而導(dao)致的(de)(de)(de)(de)副作用(yong)(yong)；另一(yi)方(fang)面，可(ke)使(shi)(shi)充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)直線進(jin)行，加(jia)快了(le)(le)(le)充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)(de)速(su)度(du)，也(ye)(ye)可(ke)避免(mian)接近(jin)浮(fu)充(chong)(chong)(chong)(chong)(chong)(chong)值時的(de)(de)(de)(de)過(guo)于(yu)緩(huan)慢的(de)(de)(de)(de)過(guo)程(cheng)。這(zhe)(zhe)種(zhong)方(fang)法也(ye)(ye)有不足之處，因為隨著充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)過(guo)程(cheng)的(de)(de)(de)(de)進(jin)行，未經反(fan)(fan)應的(de)(de)(de)(de)物質會(hui)(hui)(hui)越來(lai)越少，如果仍用(yong)(yong)充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)初期的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)流注入，由(you)于(yu)反(fan)(fan)應物質的(de)(de)(de)(de)缺乏就(jiu)會(hui)(hui)(hui)用(yong)(yong)水(shui)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)解(jie)來(lai)填補，這(zhe)(zhe)又會(hui)(hui)(hui)導(dao)致水(shui)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)離物氫和(he)氧(yang)的(de)(de)(de)(de)快速(su)蒸發，從而也(ye)(ye)縮短(duan)(duan)了(le)(le)(le)電(dian)(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)服(fu)務壽(shou)命(ming)。因此也(ye)(ye)有的(de)(de)(de)(de)提(ti)出在電(dian)(dian)(dian)(dian)(dian)池浮(fu)充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)到(dao)“一(yi)定值”時將充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流減(jian)半(ban)。就(jiu)是(shi)這(zhe)(zhe)個“一(yi)定值”也(ye)(ye)很(hen)難(nan)掌握(wo)，尤其是(shi)接近(jin)額(e)定浮(fu)充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)壓值時，如果仍用(yong)(yong)這(zhe)(zhe)個即(ji)使(shi)(shi)是(shi)減(jian)了(le)(le)(le)半(ban)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)流強行灌(guan)入，也(ye)(ye)會(hui)(hui)(hui)加(jia)快電(dian)(dian)(dian)(dian)(dian)解(jie)水(shui)的(de)(de)(de)(de)進(jin)程(cheng)，縮短(duan)(duan)電(dian)(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)壽(shou)命(ming)。因此這(zhe)(zhe)個界限也(ye)(ye)難(nan)于(yu)劃分和(he)掌握(wo)。此種(zhong)方(fang)法有的(de)(de)(de)(de)在均衡(heng)充(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)中(zhong)使(shi)(shi)用(yong)(yong)。

3.恒流恒壓充電

　　鑒于(yu)上述兩種充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)方式(shi)(shi)的(de)(de)優點(dian)和不(bu)足，于(yu)是(shi)就推(tui)出(chu)了將二者優點(dian)集合與一體的(de)(de)所謂恒(heng)流(liu)(liu)(liu)恒(heng)壓(ya)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)方式(shi)(shi)，實際(ji)上是(shi)限流(liu)(liu)(liu)恒(heng)壓(ya)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)方式(shi)(shi)。在充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)初期由于(yu)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)有可能非常大(da)(da)，所以這時(shi)(shi)的(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)路將該電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)限制在一個規定值，使之能最(zui)大(da)(da)限度地保(bao)證(zheng)(zheng)既能快(kuai)速充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)，又(you)能保(bao)證(zheng)(zheng)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)過程的(de)(de)安(an)全(quan)。這一段的(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)幾(ji)乎是(shi)線性(xing)的(de)(de)，隨著充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)過程的(de)(de)進(jin)行，大(da)(da)約(yue)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)至80%～90%電(dian)(dian)(dian)(dian)池容量時(shi)(shi)，充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)開(kai)始小(xiao)于(yu)限流(liu)(liu)(liu)值，其電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)變化開(kai)始遵從式(shi)(shi)(1)。目前UPS中的(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)大(da)(da)都(dou)采用這種方式(shi)(shi)。

4.充電電路

　　(1)概述  UPS中(zhong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)不外乎(hu)兩種：降壓充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)和(he)升壓充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)。在(zai)一些小(xiao)容(rong)量(liang)UPS中(zhong)，由于(yu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)組(zu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓比較低(di)(di)，故多(duo)(duo)用降壓電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)，比如Smart、Matrix和(he)Symmetra等系列(lie)UPS中(zhong)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)組(zu)額定電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓最高(gao)也就是(shi)120V，浮充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓也小(xiao)于(yu)140V，由單相220V交流電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓足可(ke)以得到(dao)此值；為了(le)提高(gao)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)器的效率和(he)降低(di)(di)功(gong)耗(hao)，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)器多(duo)(duo)采用稱為Buck電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)的高(gao)頻PWM方案(an)，這(zhe)在(zai)前面已有(you)介(jie)紹。在(zai)中(zhong)大容(rong)量(liang)的UPS系統中(zhong)，輸(shu)入(ru)多(duo)(duo)是(shi)三相電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓，又(you)由于(yu)輸(shu)入(ru)整流器采用了(le)相控的晶閘(zha)管方案(an)，本身的輸(shu)出電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓穩定度(du)已達到(dao)了(le)蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的要求，故電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)功(gong)能統一由整流器負擔(dan)，這(zhe)也是(shi)一個降壓充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)。

　　只有一部分(fen)小(xiao)容量(liang)UPS采用了(le)高(gao)壓(ya)(ya)(ya)電(dian)(dian)池組(zu)，比如單相(xiang)220V輸(shu)入(ru)的(de)Imel 7.5kVA UPS就采用了(le)384V的(de)電(dian)(dian)池電(dian)(dian)壓(ya)(ya)(ya)，遠(yuan)遠(yuan)超過(guo)了(le)220V交流電(dian)(dian)壓(ya)(ya)(ya)幅(fu)值(zhi)310V，因此不提高(gao)電(dian)(dian)壓(ya)(ya)(ya)就無(wu)法滿(man)足電(dian)(dian)池組(zu)的(de)充電(dian)(dian)要求。所以機器(qi)中就采用了(le)稱為Boost的(de)升(sheng)壓(ya)(ya)(ya)PWM電(dian)(dian)路。

　　一般UPS電(dian)源的(de)(de)(de)后備時(shi)間(jian)(jian)大都在10min左(zuo)右，充電(dian)器(qi)的(de)(de)(de)設計也與此對應。如遇(yu)有長延(yan)時(shi)的(de)(de)(de)要(yao)求，雖然(ran)增加了電(dian)池可以滿(man)足其放電(dian)的(de)(de)(de)能力，但充電(dian)的(de)(de)(de)速度就(jiu)遠(yuan)達不(bu)到目的(de)(de)(de)了。比如一般UPS內(nei)含(han)10min電(dian)池時(shi)，放電(dian)后重新(xin)充電(dian)的(de)(de)(de)時(shi)間(jian)(jian)為10～12h。當(dang)有的(de)(de)(de)用戶提出了8h要(yao)求時(shi)，電(dian)池容量(liang)增加到原來的(de)(de)(de)48倍！若充足如此大的(de)(de)(de)電(dian)池顯然(ran)不(bu)能靠UPS的(de)(de)(de)內(nei)部(bu)充電(dian)器(qi)了。于是就(jiu)提出了外(wai)加充電(dian)器(qi)的(de)(de)(de)要(yao)求。

　　(2)UPS外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)的(de)(de)配(pei)置原則  UPS外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)的(de)(de)配(pei)置原則首先(xian)是要(yao)和UPS隔(ge)離(li)(li)，其次(ci)才是電(dian)(dian)(dian)(dian)磁兼容指(zhi)標(biao)要(yao)和UPS相適應。以往市(shi)場上的(de)(de)商品(pin)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)雖然(ran)(ran)(ran)也考慮了隔(ge)離(li)(li)問題，并且也采(cai)取了措(cuo)施，但由(you)于(yu)措(cuo)施不利，也不乏導(dao)致UPS故(gu)障的(de)(de)例子。圖2就(jiu)是一(yi)般(ban)外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)隔(ge)離(li)(li)措(cuo)施圖，實際上所(suo)謂的(de)(de)隔(ge)離(li)(li)措(cuo)施就(jiu)是一(yi)只二極(ji)管(guan)。GB1是UPS內(nei)部(bu)電(dian)(dian)(dian)(dian)池組，GB2是外(wai)加(jia)(jia)(jia)長延時電(dian)(dian)(dian)(dian)池組，而(er)(er)往往由(you)于(yu)外(wai)加(jia)(jia)(jia)電(dian)(dian)(dian)(dian)池組的(de)(de)容量(liang)遠大于(yu)內(nei)部(bu)電(dian)(dian)(dian)(dian)池組，一(yi)般(ban)將GB1省掉了，無(wu)論(lun)是省掉還是不省掉，都有(you)一(yi)個不變的(de)(de)事(shi)實，即UPS內(nei)部(bu)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)和外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)的(de)(de)直(zhi)(zhi)(zhi)接(jie)(jie)并聯。為了隔(ge)離(li)(li)相互間的(de)(de)影(ying)(ying)響(xiang)，多(duo)數外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)多(duo)在其輸出正(zheng)端串(chuan)聯了一(yi)只正(zheng)向二極(ji)管(guan)D。這樣做(zuo)的(de)(de)結果(guo)是隔(ge)離(li)(li)了UPS對(dui)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)的(de)(de)影(ying)(ying)響(xiang)，保(bao)證了它不受(shou)其干(gan)(gan)(gan)擾，但沒有(you)消(xiao)除充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)對(dui)UPS的(de)(de)干(gan)(gan)(gan)擾。而(er)(er)且最關鍵的(de)(de)就(jiu)是怕外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)對(dui)UPS的(de)(de)干(gan)(gan)(gan)擾。當(dang)外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓因失控而(er)(er)突然(ran)(ran)(ran)增高時，它就(jiu)會(hui)(hui)通過(guo)二極(ji)管(guan)去干(gan)(gan)(gan)擾UPS，如果(guo)該外(wai)加(jia)(jia)(jia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)(qi)(qi)(qi)(qi)的(de)(de)輸出電(dian)(dian)(dian)(dian)壓是由(you)市(shi)電(dian)(dian)(dian)(dian)直(zhi)(zhi)(zhi)接(jie)(jie)整流后通過(guo)開關管(guan)斬波(PWM)而(er)(er)來(lai)，這就(jiu)將市(shi)電(dian)(dian)(dian)(dian)直(zhi)(zhi)(zhi)接(jie)(jie)接(jie)(jie)入UPS直(zhi)(zhi)(zhi)流電(dian)(dian)(dian)(dian)路(lu)(lu)，就(jiu)會(hui)(hui)導(dao)致故(gu)障。當(dang)然(ran)(ran)(ran)，此類故(gu)障不會(hui)(hui)多(duo)見，但導(dao)致UPS冒煙的(de)(de)例子已經(jing)有(you)過(guo)。這種明顯存在隱患的(de)(de)電(dian)(dian)(dian)(dian)路(lu)(lu)一(yi)定要(yao)謹用(yong)。

　　圖2 一般外加充電器隔離措施(shi)圖

　　為了完(wan)(wan)全(quan)隔(ge)離相互間的(de)干(gan)擾，圖3的(de)外加充電器完(wan)(wan)全(quan)隔(ge)離方案(an)是可取的(de)，并在長期的(de)實踐運(yun)行中得到了證(zheng)明，既安全(quan)又可靠。{{分頁}}

　　圖(tu)3 外(wai)加(jia)充電器完全隔離方案原理圖(tu)

　　①外加充電器完全隔離(li)方案設計思(si)想：

　　a.充分保證UPS電路的完整性，即(ji)該方(fang)案不動UPS的一(yi)點(dian)一(yi)線(xian)，不從UPS機(ji)內(nei)引出任(ren)何附加(jia)的信號線(xian)。按照(zhao)UPS正常的要求，只從UPS的輸出接線(xian)端子做正常連接。

　　b.在(zai)外(wai)加充電器與UPS電池之(zhi)間(jian)(jian)加接(jie)一(yi)個(ge)(ge)簡單的三端(duan)雙向互投(tou)機(ji)構，如圖3所示，用一(yi)個(ge)(ge)中間(jian)(jian)繼電器J（或接(jie)觸(chu)器甚至雙投(tou)手動開關），將(jiang)該機(ji)構的中間(jian)(jian)臂3接(jie)外(wai)加電池組GB2的正極，繼電器線包J跨接(jie)在(zai)UPS市(shi)電輸(shu)入線上。

　　c.當市電(dian)(dian)正(zheng)常(chang)供電(dian)(dian)時，由(you)于繼(ji)電(dian)(dian)器線包J被激勵而將觸點(dian)(dian)臂3由(you)常(chang)閉觸點(dian)(dian)1打向(xiang)2，此(ci)時正(zheng)好是外(wai)加(jia)充(chong)(chong)(chong)電(dian)(dian)器正(zheng)常(chang)輸出(chu)充(chong)(chong)(chong)電(dian)(dian)時期，GB2被正(zheng)常(chang)充(chong)(chong)(chong)電(dian)(dian)。可以看出(chu)，此(ci)時UPS和外(wai)加(jia)充(chong)(chong)(chong)電(dian)(dian)器是完全(quan)隔離的(de)，并且UPS的(de)充(chong)(chong)(chong)電(dian)(dian)器僅僅給自己(ji)的(de)電(dian)(dian)池GB1充(chong)(chong)(chong)電(dian)(dian)，保證了其原(yuan)有的(de)一切充(chong)(chong)(chong)電(dian)(dian)功能。

　　d.當市(shi)電(dian)(dian)(dian)(dian)(dian)斷電(dian)(dian)(dian)(dian)(dian)時(shi)，繼電(dian)(dian)(dian)(dian)(dian)器線包J被(bei)釋放，中間(jian)臂3由2回到1，將外加電(dian)(dian)(dian)(dian)(dian)池(chi)組GB2并(bing)聯在(zai)GB1上，形成(cheng)了(le)純電(dian)(dian)(dian)(dian)(dian)池(chi)組的(de)(de)并(bing)聯，也就達到了(le)大容量(liang)電(dian)(dian)(dian)(dian)(dian)池(chi)長延時(shi)放電(dian)(dian)(dian)(dian)(dian)的(de)(de)目的(de)(de)。

　　e.市電(dian)(dian)恢復時，繼(ji)電(dian)(dian)器又回到“3-2”狀態。這(zhe)里可能(neng)有(you)這(zhe)樣一個問題：市電(dian)(dian)恢復時，由(you)于繼(ji)電(dian)(dian)器動作(zuo)存在惰性，有(you)可能(neng)外加電(dian)(dian)池(chi)組GB2不(bu)能(neng)及時斷開(kai)，將會造成UPS內部充電(dian)(dian)器同(tong)時為兩組電(dian)(dian)池(chi)充電(dian)(dian)的(de)(de)局面，會不(bu)會因充電(dian)(dian)電(dian)(dian)流(liu)太(tai)大(da)而導致故障呢？回答是(shi)否定的(de)(de)。因為所(suo)有(you)在線式UPS的(de)(de)充電(dian)(dian)器都是(shi)限流(liu)溫壓式的(de)(de)，所(suo)以不(bu)會過(guo)流(liu)。

　　上(shang)面只是給出了一(yi)(yi)個原(yuan)理方案，實際結構還要復雜一(yi)(yi)些。不(bu)過，用這個原(yuan)理進行隔(ge)離已經足夠了。

　　關(guan)于(yu)(yu)外(wai)加充電(dian)(dian)器(qi)(qi)(qi)的(de)(de)電(dian)(dian)磁兼容問題也不可忽視，由于(yu)(yu)現代UPS的(de)(de)用戶大都集通信和(he)大量的(de)(de)數據(ju)傳(chuan)輸為一(yi)(yi)體，尤其牽涉到(dao)無(wu)(wu)線通信，就更(geng)要(yao)求供電(dian)(dian)系統(tong)不能對用電(dian)(dian)系統(tong)有任何(he)干(gan)擾(rao)(rao)(rao)。因此(ci)，一(yi)(yi)般UPS系統(tong)都要(yao)通過一(yi)(yi)定的(de)(de)電(dian)(dian)磁兼容標準，如EN50091-2等。然而一(yi)(yi)般市面上(shang)的(de)(de)外(wai)加充電(dian)(dian)器(qi)(qi)(qi)很少注意到(dao)這些問題，恰恰PWM開關(guan)電(dian)(dian)源(yuan)就是無(wu)(wu)線通信的(de)(de)敏感干(gan)擾(rao)(rao)(rao)源(yuan)，因此(ci)不得不向其提出相應的(de)(de)要(yao)求。有時為了安全(quan)起(qi)見，采用原理(li)上(shang)的(de)(de)無(wu)(wu)干(gan)擾(rao)(rao)(rao)電(dian)(dian)路是必要(yao)的(de)(de)。圖4表示的(de)(de)就是這樣(yang)一(yi)(yi)種無(wu)(wu)干(gan)擾(rao)(rao)(rao)充電(dian)(dian)器(qi)(qi)(qi)電(dian)(dian)路原理(li)圖，這是一(yi)(yi)個典型的(de)(de)具(ju)有限流穩壓功能的(de)(de)充電(dian)(dian)器(qi)(qi)(qi)。

　　圖4 無干(gan)擾(rao)充(chong)電器電路原理圖{{分頁}}

　　②無干擾充電(dian)器電(dian)路特(te)點：

　　a.電(dian)(dian)路結構簡(jian)單、成熟、可(ke)(ke)靠。主回路只(zhi)有電(dian)(dian)容(rong)器(qi)和普通整(zheng)流(liu)器(qi)，這種(zhong)傳統(tong)器(qi)件的(de)(de)制造(zao)歷(li)史很長(chang)，已達(da)到(dao)很高的(de)(de)可(ke)(ke)靠性(xing)(xing)指標(biao)；輔助充電(dian)(dian)器(qi)也是歷(li)史很長(chang)的(de)(de)、性(xing)(xing)能指標(biao)非常好的(de)(de)傳統(tong)電(dian)(dian)路，輸出電(dian)(dian)壓(ya)精度很容(rong)易(yi)做到(dao)1%，輸出電(dian)(dian)壓(ya)紋波做到(dao)<5mV則輕而(er)易(yi)舉(ju)；測量(liang)與控制電(dian)(dian)路都是由(you)傳統(tong)的(de)(de)比較器(qi)、運算(suan)放大器(qi)之(zhi)類的(de)(de)組件構成，可(ke)(ke)靠性(xing)(xing)當然更無(wu)問題；執行器(qi)件是一只(zhi)繼電(dian)(dian)器(qi)，一般觸(chu)點(dian)的(de)(de)動(dong)作次數都在106次以(yi)上。

　　b.電(dian)(dian)路(lu)工作原理簡單、實(shi)用。充電(dian)(dian)器(qi)(qi)(qi)的(de)(de)兩個主要功能(neng)就是限(xian)流(liu)充電(dian)(dian)和穩(wen)壓(ya)浮(fu)充。該電(dian)(dian)路(lu)中(zhong)的(de)(de)限(xian)流(liu)是靠一只電(dian)(dian)容(rong)器(qi)(qi)(qi)來完(wan)成的(de)(de)，既無(wu)電(dian)(dian)流(liu)傳(chuan)感器(qi)(qi)(qi)又無(wu)反(fan)饋控制機構(gou)，僅(jin)僅(jin)靠電(dian)(dian)容(rong)本身(shen)的(de)(de)電(dian)(dian)壓(ya)自(zi)調整就實(shi)現(xian)了限(xian)流(liu)功能(neng)；大電(dian)(dian)流(liu)充電(dian)(dian)和高精度浮(fu)充溫壓(ya)分別(bie)進行，就大大簡化(hua)了電(dian)(dian)路(lu)，指(zhi)(zhi)標(biao)(biao)也容(rong)易做得好；用繼(ji)電(dian)(dian)器(qi)(qi)(qi)做主充電(dian)(dian)電(dian)(dian)路(lu)和輔助充電(dian)(dian)器(qi)(qi)(qi)（線性穩(wen)壓(ya)器(qi)(qi)(qi)）的(de)(de)切換(huan)機構(gou)而不(bu)考慮0切換(huan)，這正是利用了電(dian)(dian)路(lu)對該指(zhi)(zhi)標(biao)(biao)不(bu)加(jia)考慮的(de)(de)特點。

　　c.整個(ge)電(dian)(dian)(dian)路的工作狀(zhuang)態都是線(xian)(xian)性的，無產生高頻干擾的機構和(he)過程。主回路的電(dian)(dian)(dian)容器(qi)和(he)普(pu)通整流(liu)器(qi)都自然地(di)工作于50Hz，線(xian)(xian)性穩壓器(qi)從(cong)小信號到大(da)信號都是典型的線(xian)(xian)性工作狀(zhuang)態，測量與控制(zhi)電(dian)(dian)(dian)路也僅僅是對(dui)直流(liu)電(dian)(dian)(dian)平的線(xian)(xian)性轉換。

　　因此，整個電(dian)(dian)路從原理上就杜絕了高(gao)頻干擾的(de)發生。不過這種電(dian)(dian)路比同容量的(de)PWM充電(dian)(dian)器體積要大(da)一些。因此，在那些對干擾指標要求不太(tai)嚴格(ge)的(de)地(di)方，PWM充電(dian)(dian)器還是(shi)得(de)到了廣泛的(de)應用。

　　(3)雙電池組(zu)充電器：

　　①升壓（Boost）充電(dian)(dian)(dian)電(dian)(dian)(dian)路。單電(dian)(dian)(dian)子器件(jian)的(de)(de)發(fa)(fa)展促(cu)進了UPS技術的(de)(de)發(fa)(fa)展，近年來(lai)高頻機(ji)UPS的(de)(de)出(chu)現，使該類產品的(de)(de)逆變(bian)器輸出(chu)省去了笨重的(de)(de)隔離變(bian)壓器，同時將電(dian)(dian)(dian)池(chi)由(you)一組(zu)(zu)增(zeng)加到兩(liang)組(zu)(zu)，但(dan)容量不變(bian)，比如(ru)原(yuan)來(lai)用一組(zu)(zu)電(dian)(dian)(dian)池(chi)時是100Ah，而現在變(bian)成了兩(liang)組(zu)(zu)50Ah。如(ru)圖5所示(shi)的(de)(de)GB1和GB2。兩(liang)組(zu)(zu)電(dian)(dian)(dian)池(chi)串聯連接，每組(zu)(zu)電(dian)(dian)(dian)池(chi)標(biao)稱(cheng)電(dian)(dian)(dian)壓一般為384V，兩(liang)組(zu)(zu)串聯總電(dian)(dian)(dian)壓為768V，若(ruo)按照2.25V/單元(yuan)的(de)(de)標(biao)準充電(dian)(dian)(dian)，兩(liang)組(zu)(zu)電(dian)(dian)(dian)池(chi)的(de)(de)浮充電(dian)(dian)(dian)壓就(jiu)需：