電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)質(zhi)量(liang)問題固然對UPS至(zhi)關重要，但充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器的(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)質(zhi)量(liang)在(zai)(zai)很大程(cheng)度上(shang)影(ying)(ying)響著電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)質(zhi)量(liang)，其原因在(zai)(zai)前面已經提及(ji)。尤其是電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)的(de)精度一定要保證(zheng)，因為浮(fu)(fu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)的(de)過(guo)高(gao)或過(guo)低(di)都(dou)會影(ying)(ying)響電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)壽命(ming)(ming)(ming)，圖1表示(shi)的(de)是MSE電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)與壽命(ming)(ming)(ming)的(de)關系，該實(shi)驗(yan)是在(zai)(zai)40oC的(de)條(tiao)件下(xia)加速進行的(de)。由此(ci)(ci)曲(qu)線(xian)可以看(kan)出，在(zai)(zai)這(zhe)里(li)的(de)浮(fu)(fu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)推薦(jian)值(zhi)是2.25V/cell，高(gao)于這(zhe)個值(zhi)或低(di)于這(zhe)個值(zhi)都(dou)會縮(suo)短(duan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)壽命(ming)(ming)(ming)。比如(ru)浮(fu)(fu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)是2.225V/cell時，壽命(ming)(ming)(ming)將縮(suo)短(duan)5%，而(er)浮(fu)(fu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)上(shang)升到2.4V/cell時，壽命(ming)(ming)(ming)就(jiu)縮(suo)短(duan)了40%。由此(ci)(ci)可見，維持精確(que)的(de)浮(fu)(fu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)值(zhi)是如(ru)何(he)重要。但為了使(shi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)長期(qi)使(shi)用后還能保證(zheng)各(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)的(de)平衡，采用的(de)措施是均(jun)(jun)衡充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，而(er)均(jun)(jun)衡充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)也大都(dou)是2.4V/cell，這(zhe)就(jiu)和上(shang)面的(de)曲(qu)線(xian)發生了矛盾，實(shi)際上(shang)事情就(jiu)是這(zhe)樣，有得就(jiu)有失，所以電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)在(zai)(zai)均(jun)(jun)衡充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)時一定要控制(zhi)好(hao)時間，以盡量(liang)延長電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)服務壽命(ming)(ming)(ming)。

　　圖(tu)1 MSE電(dian)(dian)池的(de)充電(dian)(dian)電(dian)(dian)壓與壽命的(de)關系（40oC加(jia)速實(shi)驗）

1.恒壓充電

　　所謂恒壓充(chong)(chong)電(dian)(dian)(dian)就是(shi)用一穩壓源給電(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)，這種方法(fa)簡單易行(xing)，也能夠保證電(dian)(dian)(dian)池(chi)的(de)(de)精確浮(fu)充(chong)(chong)電(dian)(dian)(dian)壓。但若(ruo)在電(dian)(dian)(dian)池(chi)深度放電(dian)(dian)(dian)后充(chong)(chong)電(dian)(dian)(dian)時，由于(yu)電(dian)(dian)(dian)池(chi)的(de)(de)內(nei)阻相對而言(yan)仍然很(hen)低，就會有很(hen)大的(de)(de)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)使(shi)(shi)化學反應劇烈地進行(xing)，從而產生大量的(de)(de)氣(qi)體(ti)，由于(yu)還原反應來不及進行(xing)，使(shi)(shi)殼內(nei)氣(qi)壓迅速增加(jia)，沖開排氣(qi)閥將氣(qi)體(ti)逸出，加(jia)速了電(dian)(dian)(dian)解液的(de)(de)干涸，縮短(duan)了電(dian)(dian)(dian)池(chi)的(de)(de)壽命(ming)；若(ruo)排氣(qi)閥因故(gu)障而無法(fa)打開，就會使(shi)(shi)電(dian)(dian)(dian)池(chi)的(de)(de)外殼鼓脹或破裂(lie)。隨著電(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)壓的(de)(de)升(sheng)高，充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)逐漸(jian)減小，其減小的(de)(de)規律是(shi)：

 　　                                             （1）

式中(zhong)   ICH――電池的充電電流(liu)，A；

       E――充電器的輸出電壓，V；

       UGB――電池(chi)電壓(ya)，V；

       RGB――電池的內阻，Ω。

　　上(shang)式中有三個變(bian)(bian)量ICH、UGB、RGB，充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流ICH隨(sui)(sui)著(zhu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)過(guo)程的(de)(de)進行(xing)而減小，電(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)壓(ya)UGB隨(sui)(sui)著(zhu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)過(guo)程的(de)(de)進行(xing)而升高，而電(dian)(dian)(dian)(dian)(dian)池內阻RGB隨(sui)(sui)著(zhu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)過(guo)程的(de)(de)進行(xing)而減小。這就決(jue)定了充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)過(guo)程的(de)(de)非線性。尤其是(shi)在接近浮充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)壓(ya)值時，使充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)變(bian)(bian)的(de)(de)非常緩慢，從理論上(shang)講(jiang)，充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)到額定浮充(chong)(chong)值的(de)(de)時間(jian)是(shi)無窮大。

　　這種充電方式在(zai)早期的小容量UPS中曾一(yi)度使用過(guo)，因(yin)出現了好多(duo)故障，目前(qian)一(yi)般不用了。{{分頁}}

2.恒流充電

　　恒(heng)流充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)好處在于(yu)(yu)：一(yi)方(fang)面可(ke)以限制充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流，避(bi)免了(le)由(you)于(yu)(yu)上(shang)述的(de)(de)劇烈反(fan)應而導致的(de)(de)副作(zuo)用(yong)(yong)(yong)；另一(yi)方(fang)面，可(ke)使(shi)(shi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)直線進行(xing)，加(jia)快(kuai)了(le)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)速度，也可(ke)避(bi)免接(jie)近(jin)浮(fu)(fu)(fu)充(chong)值時(shi)的(de)(de)過于(yu)(yu)緩慢的(de)(de)過程。這種(zhong)(zhong)方(fang)法(fa)也有(you)(you)不足之(zhi)處，因為隨著充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過程的(de)(de)進行(xing)，未經反(fan)應的(de)(de)物質會(hui)(hui)越來(lai)越少，如果仍用(yong)(yong)(yong)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)初期的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)流注入，由(you)于(yu)(yu)反(fan)應物質的(de)(de)缺乏就會(hui)(hui)用(yong)(yong)(yong)水的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)解來(lai)填補，這又(you)會(hui)(hui)導致水的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)離物氫和氧的(de)(de)快(kuai)速蒸發，從(cong)而也縮(suo)短了(le)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)服務壽命。因此(ci)也有(you)(you)的(de)(de)提(ti)出在電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)浮(fu)(fu)(fu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)到“一(yi)定值”時(shi)將(jiang)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流減半。就是這個“一(yi)定值”也很難(nan)掌握，尤其是接(jie)近(jin)額定浮(fu)(fu)(fu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓值時(shi)，如果仍用(yong)(yong)(yong)這個即使(shi)(shi)是減了(le)半的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)流強行(xing)灌入，也會(hui)(hui)加(jia)快(kuai)電(dian)(dian)(dian)(dian)(dian)(dian)解水的(de)(de)進程，縮(suo)短電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)壽命。因此(ci)這個界限也難(nan)于(yu)(yu)劃分和掌握。此(ci)種(zhong)(zhong)方(fang)法(fa)有(you)(you)的(de)(de)在均衡充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)中使(shi)(shi)用(yong)(yong)(yong)。

3.恒流恒壓充電

　　鑒于(yu)上述兩種充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)的(de)(de)(de)優點和不足，于(yu)是就(jiu)推(tui)出了將(jiang)(jiang)二者(zhe)優點集合與一(yi)體的(de)(de)(de)所謂恒流(liu)(liu)恒壓充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)，實際上是限(xian)(xian)流(liu)(liu)恒壓充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)。在(zai)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)初期(qi)由于(yu)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)有可能(neng)非常大(da)，所以這(zhe)時的(de)(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)路將(jiang)(jiang)該電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)限(xian)(xian)制在(zai)一(yi)個規定值，使之能(neng)最大(da)限(xian)(xian)度地保(bao)證(zheng)(zheng)既能(neng)快速(su)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)，又(you)能(neng)保(bao)證(zheng)(zheng)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過(guo)程的(de)(de)(de)安(an)全。這(zhe)一(yi)段的(de)(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)幾乎是線性的(de)(de)(de)，隨(sui)著(zhu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過(guo)程的(de)(de)(de)進行(xing)，大(da)約充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)至80%～90%電(dian)(dian)(dian)(dian)(dian)(dian)池容量(liang)時，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)開(kai)始小于(yu)限(xian)(xian)流(liu)(liu)值，其電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)(de)(de)變化開(kai)始遵從式(shi)(1)。目前(qian)UPS中的(de)(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)大(da)都采用這(zhe)種方式(shi)。

4.充電電路

　　(1)概述  UPS中(zhong)電(dian)(dian)(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)不外乎兩(liang)種：降壓(ya)(ya)(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)和(he)升壓(ya)(ya)(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)。在一(yi)些(xie)小(xiao)容量UPS中(zhong)，由于(yu)(yu)電(dian)(dian)(dian)(dian)(dian)(dian)池組電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)比較低(di)(di)，故多用(yong)降壓(ya)(ya)(ya)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)，比如(ru)Smart、Matrix和(he)Symmetra等系列UPS中(zhong)，電(dian)(dian)(dian)(dian)(dian)(dian)池組額定(ding)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)最高也(ye)就是(shi)120V，浮充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)也(ye)小(xiao)于(yu)(yu)140V，由單相(xiang)220V交流電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)足(zu)可以得到此值；為了(le)提高充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)的(de)(de)(de)(de)效率和(he)降低(di)(di)功耗，充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)多采(cai)用(yong)稱為Buck電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)的(de)(de)(de)(de)高頻(pin)PWM方案(an)，這(zhe)在前面已(yi)有介紹。在中(zhong)大容量的(de)(de)(de)(de)UPS系統(tong)中(zhong)，輸(shu)(shu)入多是(shi)三(san)相(xiang)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，又由于(yu)(yu)輸(shu)(shu)入整流器(qi)采(cai)用(yong)了(le)相(xiang)控的(de)(de)(de)(de)晶(jing)閘管方案(an)，本身的(de)(de)(de)(de)輸(shu)(shu)出電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)穩定(ding)度已(yi)達到了(le)蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)要求，故電(dian)(dian)(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)功能統(tong)一(yi)由整流器(qi)負擔，這(zhe)也(ye)是(shi)一(yi)個(ge)降壓(ya)(ya)(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)。

　　只(zhi)有一部(bu)分小容量UPS采用(yong)了(le)(le)(le)高(gao)壓(ya)(ya)(ya)電(dian)(dian)池組(zu)，比如(ru)單相(xiang)220V輸(shu)入的(de)Imel 7.5kVA UPS就采用(yong)了(le)(le)(le)384V的(de)電(dian)(dian)池電(dian)(dian)壓(ya)(ya)(ya)，遠遠超(chao)過了(le)(le)(le)220V交流(liu)電(dian)(dian)壓(ya)(ya)(ya)幅值310V，因此不提高(gao)電(dian)(dian)壓(ya)(ya)(ya)就無(wu)法滿足電(dian)(dian)池組(zu)的(de)充電(dian)(dian)要求。所(suo)以機器(qi)中(zhong)就采用(yong)了(le)(le)(le)稱(cheng)為Boost的(de)升壓(ya)(ya)(ya)PWM電(dian)(dian)路。

　　一般UPS電(dian)源的后(hou)備時(shi)(shi)間(jian)大都在10min左右(you)，充(chong)(chong)電(dian)器的設計也與此對應。如遇有(you)長延時(shi)(shi)的要求(qiu)，雖然增加(jia)了(le)電(dian)池(chi)可以滿足其放電(dian)的能力，但充(chong)(chong)電(dian)的速(su)度就遠達(da)不到(dao)(dao)目的了(le)。比如一般UPS內含(han)10min電(dian)池(chi)時(shi)(shi)，放電(dian)后(hou)重新充(chong)(chong)電(dian)的時(shi)(shi)間(jian)為10～12h。當有(you)的用戶(hu)提(ti)出(chu)了(le)8h要求(qiu)時(shi)(shi)，電(dian)池(chi)容量增加(jia)到(dao)(dao)原來的48倍！若充(chong)(chong)足如此大的電(dian)池(chi)顯然不能靠(kao)UPS的內部充(chong)(chong)電(dian)器了(le)。于是就提(ti)出(chu)了(le)外加(jia)充(chong)(chong)電(dian)器的要求(qiu)。

　　(2)UPS外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)配(pei)置(zhi)原則  UPS外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)配(pei)置(zhi)原則首先(xian)是(shi)(shi)(shi)(shi)要(yao)和UPS隔(ge)離(li)(li)，其(qi)次才是(shi)(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)(dian)磁兼容指(zhi)標要(yao)和UPS相適應。以(yi)往市(shi)場上的(de)(de)(de)商品(pin)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)雖(sui)然(ran)也考慮了(le)隔(ge)離(li)(li)問題，并且也采取了(le)措(cuo)(cuo)施，但(dan)由(you)于措(cuo)(cuo)施不(bu)(bu)利，也不(bu)(bu)乏導(dao)致UPS故障(zhang)(zhang)的(de)(de)(de)例子。圖2就(jiu)是(shi)(shi)(shi)(shi)一(yi)般外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)隔(ge)離(li)(li)措(cuo)(cuo)施圖，實際上所(suo)謂(wei)的(de)(de)(de)隔(ge)離(li)(li)措(cuo)(cuo)施就(jiu)是(shi)(shi)(shi)(shi)一(yi)只二極(ji)(ji)管(guan)。GB1是(shi)(shi)(shi)(shi)UPS內(nei)部電(dian)(dian)(dian)(dian)(dian)(dian)池組，GB2是(shi)(shi)(shi)(shi)外加長(chang)延時(shi)電(dian)(dian)(dian)(dian)(dian)(dian)池組，而(er)往往由(you)于外加電(dian)(dian)(dian)(dian)(dian)(dian)池組的(de)(de)(de)容量遠大于內(nei)部電(dian)(dian)(dian)(dian)(dian)(dian)池組，一(yi)般將GB1省(sheng)掉了(le)，無論是(shi)(shi)(shi)(shi)省(sheng)掉還是(shi)(shi)(shi)(shi)不(bu)(bu)省(sheng)掉，都有一(yi)個不(bu)(bu)變的(de)(de)(de)事實，即UPS內(nei)部充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)和外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)直接(jie)(jie)并聯(lian)。為了(le)隔(ge)離(li)(li)相互間的(de)(de)(de)影(ying)響，多數外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)多在其(qi)輸(shu)(shu)出正(zheng)端串聯(lian)了(le)一(yi)只正(zheng)向(xiang)二極(ji)(ji)管(guan)D。這(zhe)樣做的(de)(de)(de)結果(guo)(guo)是(shi)(shi)(shi)(shi)隔(ge)離(li)(li)了(le)UPS對(dui)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)影(ying)響，保證了(le)它不(bu)(bu)受其(qi)干擾(rao)(rao)，但(dan)沒有消除充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)對(dui)UPS的(de)(de)(de)干擾(rao)(rao)。而(er)且最關鍵的(de)(de)(de)就(jiu)是(shi)(shi)(shi)(shi)怕外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)對(dui)UPS的(de)(de)(de)干擾(rao)(rao)。當(dang)(dang)外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)因(yin)失控而(er)突然(ran)增高時(shi)，它就(jiu)會(hui)(hui)通過(guo)二極(ji)(ji)管(guan)去干擾(rao)(rao)UPS，如(ru)果(guo)(guo)該外加充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)輸(shu)(shu)出電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)是(shi)(shi)(shi)(shi)由(you)市(shi)電(dian)(dian)(dian)(dian)(dian)(dian)直接(jie)(jie)整流后通過(guo)開(kai)關管(guan)斬波(bo)(PWM)而(er)來，這(zhe)就(jiu)將市(shi)電(dian)(dian)(dian)(dian)(dian)(dian)直接(jie)(jie)接(jie)(jie)入UPS直流電(dian)(dian)(dian)(dian)(dian)(dian)路，就(jiu)會(hui)(hui)導(dao)致故障(zhang)(zhang)。當(dang)(dang)然(ran)，此類(lei)故障(zhang)(zhang)不(bu)(bu)會(hui)(hui)多見，但(dan)導(dao)致UPS冒煙的(de)(de)(de)例子已經有過(guo)。這(zhe)種明顯存在隱(yin)患的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)路一(yi)定要(yao)謹用。

　　圖2 一(yi)般外加充(chong)電器隔(ge)離措(cuo)施圖

　　為(wei)了(le)完全(quan)隔離相互間(jian)的干擾，圖3的外加(jia)充(chong)電(dian)器完全(quan)隔離方(fang)案(an)是(shi)可取的，并在長期的實踐運(yun)行中(zhong)得到了(le)證(zheng)明，既安全(quan)又可靠。{{分(fen)頁(ye)}}

　　圖3 外加(jia)充電器完全隔離(li)方案原理圖

　　①外加(jia)充電(dian)器完(wan)全隔(ge)離方案設(she)計思(si)想(xiang)：

　　a.充(chong)分保證UPS電路(lu)的完整性(xing)，即該方(fang)案不動UPS的一(yi)點一(yi)線(xian)，不從UPS機內(nei)引出任何(he)附(fu)加的信號線(xian)。按(an)照UPS正常(chang)的要求(qiu)，只從UPS的輸出接線(xian)端子(zi)做正常(chang)連接。

　　b.在外加(jia)(jia)充電器與UPS電池之間(jian)(jian)加(jia)(jia)接一個(ge)簡(jian)單的(de)三端雙(shuang)向互投(tou)機構，如圖(tu)3所(suo)示，用一個(ge)中間(jian)(jian)繼電器J（或接觸器甚至雙(shuang)投(tou)手(shou)動開關），將該機構的(de)中間(jian)(jian)臂3接外加(jia)(jia)電池組GB2的(de)正極(ji)，繼電器線包J跨接在UPS市(shi)電輸入線上。

　　c.當市電(dian)正常供電(dian)時，由于繼電(dian)器線包J被(bei)激(ji)勵而將觸(chu)點(dian)臂3由常閉(bi)觸(chu)點(dian)1打向2，此時正好是(shi)(shi)外加(jia)(jia)充(chong)電(dian)器正常輸出充(chong)電(dian)時期，GB2被(bei)正常充(chong)電(dian)。可以(yi)看出，此時UPS和外加(jia)(jia)充(chong)電(dian)器是(shi)(shi)完全隔離的(de)(de)(de)，并(bing)且UPS的(de)(de)(de)充(chong)電(dian)器僅僅給(gei)自己的(de)(de)(de)電(dian)池GB1充(chong)電(dian)，保證了其原(yuan)有的(de)(de)(de)一切充(chong)電(dian)功能。

　　d.當市(shi)電(dian)(dian)(dian)斷(duan)電(dian)(dian)(dian)時，繼電(dian)(dian)(dian)器線包J被釋放，中間臂3由2回(hui)到1，將外加電(dian)(dian)(dian)池組GB2并聯(lian)在GB1上，形成了(le)純電(dian)(dian)(dian)池組的并聯(lian)，也就達到了(le)大容量電(dian)(dian)(dian)池長延時放電(dian)(dian)(dian)的目的。

　　e.市(shi)電(dian)(dian)恢復(fu)時(shi)，繼(ji)(ji)電(dian)(dian)器(qi)又回(hui)到(dao)“3-2”狀(zhuang)態。這里可能有這樣一個(ge)問題：市(shi)電(dian)(dian)恢復(fu)時(shi)，由于繼(ji)(ji)電(dian)(dian)器(qi)動作(zuo)存在惰性(xing)，有可能外加電(dian)(dian)池組(zu)GB2不(bu)能及時(shi)斷開，將會造成UPS內部(bu)充(chong)電(dian)(dian)器(qi)同時(shi)為兩組(zu)電(dian)(dian)池充(chong)電(dian)(dian)的局面(mian)，會不(bu)會因充(chong)電(dian)(dian)電(dian)(dian)流(liu)太大而(er)導致故障呢？回(hui)答是否定的。因為所有在線式UPS的充(chong)電(dian)(dian)器(qi)都(dou)是限流(liu)溫壓式的，所以不(bu)會過流(liu)。

　　上面(mian)只是給(gei)出了一個原理方案，實際結構還要復雜一些(xie)。不(bu)過，用這(zhe)個原理進行隔(ge)離已經足夠(gou)了。

　　關于(yu)外加(jia)充(chong)電(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)電(dian)(dian)(dian)磁(ci)兼容(rong)(rong)問題(ti)也(ye)不可(ke)忽視，由于(yu)現(xian)代(dai)UPS的(de)(de)(de)用戶大都集通(tong)信(xin)和(he)大量的(de)(de)(de)數據傳輸(shu)為一(yi)體，尤其(qi)(qi)牽涉到(dao)無線(xian)通(tong)信(xin)，就(jiu)更要(yao)求供(gong)電(dian)(dian)(dian)系(xi)統(tong)不能對用電(dian)(dian)(dian)系(xi)統(tong)有任何干擾。因(yin)此(ci)，一(yi)般UPS系(xi)統(tong)都要(yao)通(tong)過(guo)一(yi)定的(de)(de)(de)電(dian)(dian)(dian)磁(ci)兼容(rong)(rong)標準(zhun)，如EN50091-2等。然而(er)一(yi)般市面上(shang)的(de)(de)(de)外加(jia)充(chong)電(dian)(dian)(dian)器(qi)(qi)很(hen)少注意到(dao)這些問題(ti)，恰恰PWM開關電(dian)(dian)(dian)源就(jiu)是(shi)無線(xian)通(tong)信(xin)的(de)(de)(de)敏感(gan)干擾源，因(yin)此(ci)不得(de)不向其(qi)(qi)提出(chu)相應(ying)的(de)(de)(de)要(yao)求。有時(shi)為了安全起(qi)見，采用原理上(shang)的(de)(de)(de)無干擾電(dian)(dian)(dian)路(lu)(lu)是(shi)必(bi)要(yao)的(de)(de)(de)。圖4表示的(de)(de)(de)就(jiu)是(shi)這樣一(yi)種無干擾充(chong)電(dian)(dian)(dian)器(qi)(qi)電(dian)(dian)(dian)路(lu)(lu)原理圖，這是(shi)一(yi)個(ge)典型的(de)(de)(de)具(ju)有限流穩(wen)壓功能的(de)(de)(de)充(chong)電(dian)(dian)(dian)器(qi)(qi)。

　　圖4 無干擾充電(dian)器(qi)電(dian)路原理圖{{分頁(ye)}}

　　②無干擾充電器電路特點：

　　a.電(dian)(dian)(dian)路結構(gou)(gou)簡單(dan)、成熟(shu)、可(ke)靠。主回路只(zhi)有(you)電(dian)(dian)(dian)容(rong)器(qi)和普(pu)通整流器(qi)，這種傳(chuan)統器(qi)件(jian)的制造歷(li)史很(hen)長，已達到很(hen)高的可(ke)靠性指(zhi)標(biao)；輔助(zhu)充電(dian)(dian)(dian)器(qi)也是歷(li)史很(hen)長的、性能指(zhi)標(biao)非常(chang)好的傳(chuan)統電(dian)(dian)(dian)路，輸出電(dian)(dian)(dian)壓精度很(hen)容(rong)易做到1%，輸出電(dian)(dian)(dian)壓紋(wen)波做到<5mV則輕而易舉；測量與控制電(dian)(dian)(dian)路都(dou)是由傳(chuan)統的比較(jiao)器(qi)、運算放(fang)大器(qi)之類的組(zu)件(jian)構(gou)(gou)成，可(ke)靠性當然(ran)更無(wu)問(wen)題；執行器(qi)件(jian)是一只(zhi)繼電(dian)(dian)(dian)器(qi)，一般觸點的動作次數都(dou)在106次以上。

　　b.電(dian)(dian)(dian)路(lu)工(gong)作原理簡單、實(shi)用(yong)。充(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)的(de)(de)兩個主(zhu)要(yao)功能就是(shi)限流充(chong)(chong)電(dian)(dian)(dian)和(he)穩壓浮充(chong)(chong)。該(gai)電(dian)(dian)(dian)路(lu)中的(de)(de)限流是(shi)靠(kao)(kao)一只電(dian)(dian)(dian)容(rong)器(qi)(qi)來完成的(de)(de)，既無電(dian)(dian)(dian)流傳感(gan)器(qi)(qi)又(you)無反饋控制機構，僅(jin)僅(jin)靠(kao)(kao)電(dian)(dian)(dian)容(rong)本身的(de)(de)電(dian)(dian)(dian)壓自調整(zheng)就實(shi)現了限流功能；大(da)電(dian)(dian)(dian)流充(chong)(chong)電(dian)(dian)(dian)和(he)高精度浮充(chong)(chong)溫壓分別進行，就大(da)大(da)簡化了電(dian)(dian)(dian)路(lu)，指(zhi)標也容(rong)易做(zuo)得好；用(yong)繼(ji)電(dian)(dian)(dian)器(qi)(qi)做(zuo)主(zhu)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)路(lu)和(he)輔助充(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)（線性(xing)穩壓器(qi)(qi)）的(de)(de)切換機構而不考(kao)慮0切換，這正是(shi)利用(yong)了電(dian)(dian)(dian)路(lu)對(dui)該(gai)指(zhi)標不加(jia)考(kao)慮的(de)(de)特點。

　　c.整(zheng)個(ge)電(dian)(dian)路(lu)的(de)工作狀(zhuang)(zhuang)態都是(shi)線(xian)性(xing)的(de)，無(wu)產生高頻干擾的(de)機構和過(guo)程。主回路(lu)的(de)電(dian)(dian)容器和普通整(zheng)流器都自(zi)然地(di)工作于50Hz，線(xian)性(xing)穩壓器從小信號(hao)到大信號(hao)都是(shi)典型的(de)線(xian)性(xing)工作狀(zhuang)(zhuang)態，測(ce)量與(yu)控制電(dian)(dian)路(lu)也(ye)僅(jin)僅(jin)是(shi)對直流電(dian)(dian)平(ping)的(de)線(xian)性(xing)轉換(huan)。

　　因(yin)此(ci)，整個電路從(cong)原理上就杜(du)絕了高頻干(gan)擾(rao)的(de)發生。不(bu)過(guo)這種電路比同容量的(de)PWM充電器體積要(yao)(yao)大一些。因(yin)此(ci)，在(zai)那(nei)些對干(gan)擾(rao)指標要(yao)(yao)求不(bu)太嚴格(ge)的(de)地方，PWM充電器還是(shi)得到了廣(guang)泛(fan)的(de)應用。

　　(3)雙電(dian)池組充(chong)電(dian)器：

　　①升壓(ya)（Boost）充電(dian)(dian)電(dian)(dian)路。單(dan)電(dian)(dian)子(zi)器(qi)件的發展促進(jin)了UPS技術(shu)的發展，近年來(lai)高頻機UPS的出現，使該類產品的逆變器(qi)輸出省去了笨重的隔(ge)離變壓(ya)器(qi)，同時將電(dian)(dian)池(chi)(chi)由一(yi)組增加到兩(liang)組，但(dan)容量(liang)不變，比如原來(lai)用一(yi)組電(dian)(dian)池(chi)(chi)時是(shi)100Ah，而現在變成了兩(liang)組50Ah。如圖(tu)5所示的GB1和GB2。兩(liang)組電(dian)(dian)池(chi)(chi)串聯(lian)連接，每(mei)組電(dian)(dian)池(chi)(chi)標稱電(dian)(dian)壓(ya)一(yi)般為384V，兩(liang)組串聯(lian)總(zong)電(dian)(dian)壓(ya)為768V，若按照2.25V/單(dan)元(yuan)的標準(zhun)充電(dian)(dian)，兩(liang)組電(dian)(dian)池(chi)(chi)的浮充電(dian)(dian)壓(ya)就需：