鉛酸蓄電池由(you)于其成本(ben)低(di)、容(rong)量(liang)大、安全(quan)可靠等特(te)點，在通(tong)信、電動(dong)汽車、軍事(shi)、航(hang)(hang)空航(hang)(hang)天(tian)等各個(ge)領域都(dou)有(you)廣泛的(de)應(ying)用。電池的(de)性能(neng)好壞、使用壽(shou)(shou)命(ming)的(de)長短直接影響到電子(zi)產(chan)品的(de)使用壽(shou)(shou)命(ming)和使用安全(quan)；而(er)充電器的(de)好壞又直接影響到電池的(de)使用壽(shou)(shou)命(ming)。因此研究低(di)成本(ben)又有(you)智(zhi)能(neng)管理功能(neng)的(de)充電器是(shi)有(you)實(shi)際應(ying)用價值的(de)課題。

　　1 目前(qian)智能充電器的幾種結構［1］

　　1.1 基于專(zhuan)用(yong)芯片的管理系統

　　現在，UNITRODE 公司已開發(fa)出系列電(dian)池(chi)管(guan)(guan)理(li)(li)專(zhuan)用(yong)芯片。因為(wei)電(dian)池(chi)管(guan)(guan)理(li)(li)中采用(yong)最多(duo)的(de)就(jiu)是控(kong)制(zhi)充(chong)電(dian)電(dian)壓及充(chong)放電(dian)電(dian)流(liu)，電(dian)池(chi)管(guan)(guan)理(li)(li)芯片正是抓住了(le)(le)這一點，為(wei)VRLA 電(dian)池(chi)研制(zhi)了(le)(le)具有(you)(you)四(si)狀態管(guan)(guan)理(li)(li)的(de)專(zhuan)用(yong)控(kong)制(zhi)芯片，可以智能地實現帶溫度(du)補(bu)償的(de)四(si)狀態管(guan)(guan)理(li)(li)方(fang)案(an)：涓流(liu)充(chong)電(dian)模式、大(da)功(gong)率充(chong)電(dian)模式、過充(chong)電(dian)模式和(he)浮充(chong)電(dian)模式。不(bu)同的(de)電(dian)池(chi)要有(you)(you)不(bu)同的(de)芯片控(kong)制(zhi)，因此，用(yong)專(zhuan)用(yong)芯片做管(guan)(guan)理(li)(li)系統其靈(ling)活(huo)性較差，

　　1.2 基于監控測量的蓄電池管理系統

　　在給電(dian)池(chi)充電(dian)的過程中，涉及(ji)到電(dian)池(chi)工作電(dian)壓、工作電(dian)流(liu)、溫度等參(can)數(shu)(shu)，這(zhe)些都是表征(zheng)電(dian)池(chi)狀態的重要參(can)數(shu)(shu)。采用傳感器提取這(zhe)些參(can)數(shu)(shu)，然后再配(pei)合故(gu)障診斷、遙(yao)控遙(yao)測、自(zi)動報(bao)警和事故(gu)現場處理等功(gong)能(neng)，就可以組成一個電(dian)池(chi)管理系(xi)統。如圖1所示。

　　1.3 與(yu)電(dian)源設備一起構成的蓄電(dian)池充放電(dian)管理系統

　　在通訊、供電系統中，為了保證電網掉電時蓄電池組能及時補充電能，在規定時間內向負載供電，保證通信或電力合閘系統的正常運轉，通常是將電池組直接掛接在電源模塊輸出端。當電網正常工作時，電池組工作在浮充狀態，起到平滑濾波和保持容量（補充自放電的容量損失）的作用。一旦電網掉電，蓄電池組立即投入工作，當電網恢復，電源模塊立即對電池進行充電。如圖2 所示。

　　這樣(yang)的(de)(de)(de)一(yi)個(ge)(ge)系統(tong)由于和電(dian)(dian)源(yuan)模塊聯(lian)系起來，所以，可(ke)以從充放(fang)電(dian)(dian)過程上來優化電(dian)(dian)池(chi)(chi)工作(zuo)狀態，電(dian)(dian)池(chi)(chi)充電(dian)(dian)成為可(ke)控的(de)(de)(de)過程，建(jian)立在這樣(yang)一(yi)個(ge)(ge)系統(tong)上的(de)(de)(de)監(jian)控單元應該具有(you)第一(yi)種監(jian)控系統(tong)中所有(you)功能，并且可(ke)以和電(dian)(dian)源(yuan)模塊直接“對(dui)話”，根據要求(qiu)對(dui)電(dian)(dian)池(chi)(chi)進行(xing)管理(li)，并且可(ke)以實時監(jian)控電(dian)(dian)池(chi)(chi)的(de)(de)(de)放(fang)電(dian)(dian)狀態，對(dui)電(dian)(dian)池(chi)(chi)的(de)(de)(de)工作(zuo)進行(xing)優化［2］。因此，電(dian)(dian)池(chi)(chi)組(zu)的(de)(de)(de)工作(zuo)會更(geng)加可(ke)靠，可(ke)控性(xing)和智能化程度也會更(geng)高。但是這樣(yang)一(yi)個(ge)(ge)系統(tong)存在的(de)(de)(de)主要問題是：

　　（1）沒有(you)解決電池(chi)組串聯(lian)運行過程中(zhong)不均衡 現象(xiang)的(de)問題，這也是電池(chi)失(shi)效的(de)重要原(yuan)因之一；

　　（2）一(yi)般只完成了(le)電(dian)(dian)(dian)池生產廠家提供的充電(dian)(dian)(dian)曲線，對于電(dian)(dian)(dian)池在使用過程(cheng)中發(fa)生的其它(ta)問題控制不夠全(quan)面，例如深度放(fang)電(dian)(dian)(dian)后的涓充問題等。

　　在(zai)將來，充電器(qi)的(de)發展方向(xiang)是智能(neng)化(hua)、數字化(hua)、集成化(hua)。智能(neng)化(hua)可以(yi)使電池的(de)管(guan)理做(zuo)到全(quan)自動，無需人員監管(guan)，真正做(zuo)到免維護。數字化(hua)和集成化(hua)可以(yi)減少管(guan)理系(xi)統的(de)體(ti)積(ji)和重(zhong)量(liang)，減少系(xi)統的(de)復雜度(du)。

　　2 目前幾種充電方式(shi)［3］

　　鉛酸蓄電池的(de)充電方(fang)法目前主要有恒流(liu)、恒壓(ya)、恒壓(ya)限流(liu)、脈沖充電、Reflex充電法。

　　2.1 恒流充電

　　恒流充(chong)(chong)電方式是(shi)一種(zhong)簡單(dan)的(de)充(chong)(chong)電方法(fa)。但是(shi)，恒流充(chong)(chong)電有其(qi)局限性：對電池過充(chong)(chong)電就(jiu)會(hui)造成電池壽命的(de)縮短，而過小(xiao)電流又會(hui)延長(chang)充(chong)(chong)電時間。

　　2.2 恒壓充電

　　恒壓(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)用簡單的(de)(de)控制方法很容易就能實現(xian)。在(zai)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)初始(shi)階(jie)段，由于電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)很低(di)而造(zao)成(cheng)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流很大(da)，這對電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)會(hui)造(zao)成(cheng)損害。當電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)達到(dao)一定值之后(hou)，電(dian)(dian)(dian)(dian)(dian)(dian)流就會(hui)隨之減小。這種(zhong)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方法的(de)(de)缺點(dian)就是會(hui)造(zao)成(cheng)溫度上升和電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)壽命減少，并且在(zai)開始(shi)時電(dian)(dian)(dian)(dian)(dian)(dian)流很大(da)，而后(hou)來快充(chong)(chong)滿時電(dian)(dian)(dian)(dian)(dian)(dian)流又(you)很小，就無法充(chong)(chong)分利用充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器的(de)(de)容量。

　　2.3 恒壓限流法

　　恒(heng)壓(ya)限(xian)(xian)流(liu)(liu)(liu)法(fa)(fa)實際(ji)上是將(jiang)恒(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)和恒(heng)流(liu)(liu)(liu)充(chong)(chong)電(dian)(dian)(dian)相結合，又可(ke)稱(cheng)為(wei)混(hun)合充(chong)(chong)電(dian)(dian)(dian)法(fa)(fa)。在充(chong)(chong)電(dian)(dian)(dian)開始階段，由于電(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)壓(ya)過(guo)低，為(wei)避(bi)免電(dian)(dian)(dian)流(liu)(liu)(liu)過(guo)大而損(sun)(sun)壞電(dian)(dian)(dian)池(chi)(chi)，就采用恒(heng)流(liu)(liu)(liu)充(chong)(chong)電(dian)(dian)(dian)法(fa)(fa)來限(xian)(xian)制充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)(liu)。但(dan)電(dian)(dian)(dian)壓(ya)達到預(yu)定值時(shi)，進入恒(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)方式(shi)。恒(heng)壓(ya)限(xian)(xian)流(liu)(liu)(liu)方式(shi)是大多數電(dian)(dian)(dian)池(chi)(chi)廠商推薦的(de)充(chong)(chong)電(dian)(dian)(dian)方式(shi)。由于蓄電(dian)(dian)(dian)池(chi)(chi)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)較低，充(chong)(chong)電(dian)(dian)(dian)后(hou)期電(dian)(dian)(dian)流(liu)(liu)(liu)很(hen)小，因此電(dian)(dian)(dian)解(jie)液中產生(sheng)的(de)氣泡很(hen)少，可(ke)以節省電(dian)(dian)(dian)能、降低蓄電(dian)(dian)(dian)池(chi)(chi)的(de)溫升，避(bi)免損(sun)(sun)壞電(dian)(dian)(dian)池(chi)(chi)的(de)極板。恒(heng)壓(ya)限(xian)(xian)流(liu)(liu)(liu)方式(shi)是一(yi)種很(hen)有效的(de)充(chong)(chong)電(dian)(dian)(dian)方式(shi)，加上過(guo)充(chong)(chong)判斷(duan)、浮充(chong)(chong)控制、溫度(du)補償等(deng)就可(ke)以形成一(yi)個簡單的(de)充(chong)(chong)電(dian)(dian)(dian)管理系統(tong)(tong)，蓄電(dian)(dian)(dian)池(chi)(chi)可(ke)以在這個系統(tong)(tong)下更好(hao)地(di)工作。

　　2.4 脈沖充電［4］

　　在(zai)(zai)充(chong)電(dian)(dian)(dian)(dian)過(guo)程中(zhong)，只要充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流不(bu)超過(guo)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)(chi)可(ke)接受的(de)(de)(de)電(dian)(dian)(dian)(dian)流，蓄(xu)電(dian)(dian)(dian)(dian)池(chi)(chi)內部就(jiu)不(bu)會(hui)產(chan)生大(da)量(liang)的(de)(de)(de)氣泡。蓄(xu)電(dian)(dian)(dian)(dian)池(chi)(chi)中(zhong)產(chan)生的(de)(de)(de)極(ji)化現(xian)象會(hui)阻礙充(chong)電(dian)(dian)(dian)(dian)，并且使(shi)出(chu)氣率和溫升(sheng)顯著(zhu)升(sheng)高(gao)。因此，極(ji)化電(dian)(dian)(dian)(dian)壓是(shi)影響充(chong)電(dian)(dian)(dian)(dian)速(su)度的(de)(de)(de)重(zhong)要因素。用(yong)周期性的(de)(de)(de)脈(mo)動電(dian)(dian)(dian)(dian)流給電(dian)(dian)(dian)(dian)池(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)可(ke)以使(shi)電(dian)(dian)(dian)(dian)池(chi)(chi)有時間(jian)恢復其原來狀態，減小極(ji)化現(xian)象的(de)(de)(de)影響，解決快速(su)充(chong)電(dian)(dian)(dian)(dian)面(mian)臨的(de)(de)(de)難題(ti)。但(dan)是(shi)目前這種充(chong)電(dian)(dian)(dian)(dian)方式還(huan)在(zai)(zai)研究階段(duan)，對于(yu)采(cai)用(yong)多(duo)大(da)的(de)(de)(de)脈(mo)沖周期，占空(kong)比(bi)又是(shi)多(duo)少之類的(de)(de)(de)具體(ti)問題(ti)還(huan)沒有一個定論。

　　2.5 ReflexTM充電(dian)方式

　　Reflex 充電方法是脈沖電流法的改進：一個周期是由一個正脈沖后加一個負脈沖，然后才是空閑時段。這樣就強制消除電池的極化現象，使得電池充電時可以更快而又不損害電池的使用壽命。這種充電方式與脈沖充電方式一樣，仍然處于研究階段。
.　3 數(shu)字(zi)式(shi)智能充電器(qi)的設(she)計

　　3.1 系統結構和充電(dian)方(fang)案(an)的設計

　　本文中設計的系統是(shi)一(yi)個(ge)針對12 V/（200～500Ah）的鉛酸蓄電池(chi)智能充電系統。采用半橋作(zuo)為主功率(lv)拓撲，開關頻率(lv)取80kHz左右(you)。

　　對于一個智能(neng)管理系(xi)(xi)(xi)統(tong)，控制(zhi)(zhi)模(mo)塊無異于它的(de)大腦(nao)。充電器的(de)所(suo)有動作都是由它來(lai)決定和控制(zhi)(zhi)的(de)，所(suo)以(yi)控制(zhi)(zhi)模(mo)塊的(de)選擇(ze)關系(xi)(xi)(xi)到整個系(xi)(xi)(xi)統(tong)的(de)優劣。由于系(xi)(xi)(xi)統(tong)需(xu)要(yao)多個A/D 轉換器，但不需(xu)要(yao)擴展存儲器也不需(xu)要(yao)通訊，根據以(yi)上(shang)特點我們選擇(ze)了MICROCHIP 公司的(de)PIC 系(xi)(xi)(xi)列PIC16C73 單片機。

　　圖3 所示為智能充電器的(de)(de)系統(tong)框圖。單(dan)(dan)片(pian)機是智(zhi)能充電器的(de)(de)核心部(bu)件，它根(gen)據電流、電壓采樣(yang)以(yi)(yi)及溫(wen)度采樣(yang)做(zuo)出(chu)溫(wen)度補償后的(de)(de)PWM波形輸出(chu)，經過(guo)驅動電路提供給功(gong)率電路，并且(qie)決定了智(zhi)能充電器的(de)(de)工(gong)作(zuo)狀態，可以(yi)(yi)在必要的(de)(de)情(qing)況下做(zuo)出(chu)保護動作(zuo)。意外故障(zhang)保護電路可以(yi)(yi)在單(dan)(dan)片(pian)機失效的(de)(de)情(qing)況下對電路進(jin)行強(qiang)制保護，起(qi)到雙(shuang)重保險的(de)(de)作(zuo)用(yong)。報(bao)警顯示(shi)部(bu)分用(yong)若干個LED表示(shi)系統(tong)的(de)(de)運行狀態，簡單(dan)(dan)有(you)效。

　　充(chong)(chong)電方式采用恒(heng)(heng)(heng)(heng)(heng)壓(ya)限流(liu)(liu)(liu)法。恒(heng)(heng)(heng)(heng)(heng)壓(ya)限流(liu)(liu)(liu)充(chong)(chong)電模式分兩個階(jie)(jie)段(duan)(duan)，第一階(jie)(jie)段(duan)(duan)是恒(heng)(heng)(heng)(heng)(heng)流(liu)(liu)(liu)階(jie)(jie)段(duan)(duan)，即系統(tong)給定電流(liu)(liu)(liu)值(zhi)，給電池(chi)以(yi)恒(heng)(heng)(heng)(heng)(heng)定電流(liu)(liu)(liu)充(chong)(chong)電，當電池(chi)的(de)電壓(ya)達到系統(tong)給定的(de)轉化值(zhi)，就(jiu)轉為第二階(jie)(jie)段(duan)(duan)―――恒(heng)(heng)(heng)(heng)(heng)壓(ya)階(jie)(jie)段(duan)(duan)。恒(heng)(heng)(heng)(heng)(heng)壓(ya)轉化值(zhi)會(hui)影響充(chong)(chong)入電量的(de)多少(shao)。

　　由圖(tu)4 可知(zhi)，當(dang)恒(heng)壓(ya)轉化值(zhi)（Vref）設(she)(she)置的(de)較低時，充入(ru)(ru)的(de)電(dian)量(liang)(liang)不足（圖(tu)中陰影部分就是少充入(ru)(ru)的(de)容(rong)(rong)(rong)(rong)(rong)量(liang)(liang)），沒有(you)充分利用電(dian)池的(de)容(rong)(rong)(rong)(rong)(rong)量(liang)(liang)，長期(qi)工作，會引(yin)起電(dian)池容(rong)(rong)(rong)(rong)(rong)量(liang)(liang)丟失(shi)，這(zhe)就要求把恒(heng)壓(ya)轉化值(zhi)設(she)(she)高(gao)(gao)。但(dan)是恒(heng)壓(ya)值(zhi)較高(gao)(gao)，容(rong)(rong)(rong)(rong)(rong)易(yi)在充電(dian)末期(qi)引(yin)起過充電(dian)，這(zhe)同(tong)樣會導(dao)致電(dian)池容(rong)(rong)(rong)(rong)(rong)量(liang)(liang)丟失(shi)。

　　為了解決這個(ge)矛盾(dun)，系統引進了第三個(ge)階段(duan)(duan)―――浮充(chong)(chong)(chong)(chong)階段(duan)(duan)，這樣(yang)就可以把恒壓(ya)轉化(hua)值設(she)置的比普通恒壓(ya)限流(liu)模式高，這樣(yang)可以保證(zheng)(zheng)充(chong)(chong)(chong)(chong)入(ru)足夠的電(dian)(dian)量，在充(chong)(chong)(chong)(chong)電(dian)(dian)末期轉入(ru)浮充(chong)(chong)(chong)(chong)階段(duan)(duan)，用(yong)稍低的電(dian)(dian)壓(ya)浮充(chong)(chong)(chong)(chong)充(chong)(chong)(chong)(chong)電(dian)(dian)，從(cong)而保證(zheng)(zheng)不會過充(chong)(chong)(chong)(chong)電(dian)(dian)。

　　三階段充(chong)電(dian)方(fang)法保證了充(chong)電(dian)末期不(bu)過充(chong)，同時又(you)能達(da)到滿充(chong)的(de)(de)目的(de)(de)，是一種成本較低的(de)(de)通(tong)用蓄電(dian)池充(chong)電(dian)解決(jue)方(fang)案。

　　3.2 軟件系統的(de)設計

　　圖5 為系統(tong)軟件的(de)程(cheng)序(xu)流程(cheng)圖。根據(ju)電(dian)(dian)池的(de)端電(dian)(dian)壓決定充電(dian)(dian)器工作在何種充電(dian)(dian)狀態。

　　我(wo)們做的(de)(de)是全數字化的(de)(de)改良型PI 調(diao)節環(huan)，由于(yu)(yu)PI 調(diao)節的(de)(de)積分環(huan)在前(qian)期對誤(wu)(wu)差(cha)進行積累(lei)，為(wei)了不讓積累(lei)的(de)(de)誤(wu)(wu)差(cha)影響系統的(de)(de)穩定性，所以我(wo)們在誤(wu)(wu)差(cha)等于(yu)(yu)0 時，對原有(you)積累(lei)的(de)(de)誤(wu)(wu)差(cha)清(qing)零(ling)。當誤(wu)(wu)差(cha)等于(yu)(yu)±1 時，只進行積分運(yun)算(suan)，減慢調(diao)整速(su)度，避免(mian)產生(sheng)振(zhen)蕩。

　　鉛酸(suan)蓄電池的充電電壓需要(yao)根據環境溫度進行調(diao)整，以－4 mV/℃的補(bu)償系(xi)數(shu)來調(diao)整。因此(ci)我(wo)們加入了溫度補(bu)償的功(gong)能。

　　4 實驗結果

　　圖6 為用電(dian)(dian)子(zi)負載模擬電(dian)(dian)池三階段充(chong)電(dian)(dian)過程的波形圖。從圖6 中(zhong)我(wo)們可以看出智能(neng)充(chong)電(dian)(dian)系(xi)統能(neng)夠方便(bian)地(di)實現各(ge)個充(chong)電(dian)(dian)狀態(tai)的轉換。

　　5 結語

　　用PIC 單(dan)片機可以(yi)實現(xian)全(quan)數字化(hua)的電(dian)池充電(dian)管理，結構簡單(dan)，成(cheng)本較低，并且具(ju)有很高的靈活(huo)性，通過(guo)改變軟件內設置的恒(heng)(heng)流(liu)參考值(zhi)和恒(heng)(heng)壓參考值(zhi)就可以(yi)改變系統(tong)(tong)的恒(heng)(heng)流(liu)電(dian)流(liu)和恒(heng)(heng)壓電(dian)壓值(zhi)，使得系統(tong)(tong)在不改變系統(tong)(tong)硬件設計(ji)的情況下實現(xian)給多種(zhong)不同容量的鉛酸蓄電(dian)池充電(dian)。另外可以(yi)實現(xian)有效的電(dian)池充電(dian)管理和保護功能，達到智(zhi)能化(hua)控制。