近(jin)年(nian)來隨著能(neng)源(yuan)短缺問題(ti)日益突出， 太(tai)陽能(neng)、風能(neng)等(deng)新型(xing)無污染的替(ti)代(dai)能(neng)源(yuan)應用日益受(shou)到(dao)重視。獨立型(xing)太(tai)陽能(neng)照(zhao)明系統(tong)因(yin)其結構簡單、無需鋪設(she)電(dian)纜， 且搭建、攜(xie)帶(dai)較為(wei)方便等(deng)特點在照(zhao)明領域有著廣泛應用前景。

　　但(dan)目前急(ji)需解決的(de)(de)有(you)鉛酸(suan)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)使(shi)用(yong)(yong)(yong)(yong)壽命(ming)(ming)較(jiao)(jiao)(jiao)短(duan)及系(xi)統(tong)在弱(ruo)(ruo)光(guang)(guang)條件下充(chong)(chong)電(dian)(dian)(dian)(dian)能(neng)(neng)(neng)力不足(zu)這(zhe)兩大問題。系(xi)統(tong)儲能(neng)(neng)(neng)元(yuan)件鉛酸(suan)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)設計壽命(ming)(ming)約(yue)三年， 但(dan)由于(yu)充(chong)(chong)電(dian)(dian)(dian)(dian)方(fang)(fang)式(shi)、存(cun)儲方(fang)(fang)式(shi)以及人為等諸多因(yin)素的(de)(de)影響(xiang)導(dao)致其(qi)使(shi)用(yong)(yong)(yong)(yong)壽命(ming)(ming)過短(duan)，需要(yao)經(jing)常更換， 不僅加大了(le)使(shi)用(yong)(yong)(yong)(yong)成(cheng)本也影響(xiang)了(le)系(xi)統(tong)的(de)(de)穩(wen)定(ding)(ding)性。另外大部分已使(shi)用(yong)(yong)(yong)(yong)的(de)(de)系(xi)統(tong)在弱(ruo)(ruo)光(guang)(guang)條件下充(chong)(chong)電(dian)(dian)(dian)(dian)能(neng)(neng)(neng)力不足(zu)， 導(dao)致系(xi)統(tong)太陽(yang)能(neng)(neng)(neng)板利(li)用(yong)(yong)(yong)(yong)率(lv)不高； 傳統(tong)提高弱(ruo)(ruo)光(guang)(guang)充(chong)(chong)電(dian)(dian)(dian)(dian)能(neng)(neng)(neng)力的(de)(de)方(fang)(fang)法是(shi)采(cai)(cai)用(yong)(yong)(yong)(yong)組(zu)態優化(hua)控(kong)(kong)制來(lai)(lai)實現， 即根據(ju)外界光(guang)(guang)照(zhao)強弱(ruo)(ruo)采(cai)(cai)用(yong)(yong)(yong)(yong)繼(ji)(ji)電(dian)(dian)(dian)(dian)器(qi)控(kong)(kong)制太陽(yang)能(neng)(neng)(neng)板組(zu)件按照(zhao)串(chuan)聯或(huo)并聯等不同(tong)的(de)(de)組(zu)合方(fang)(fang)式(shi)給(gei)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)(dian)， 確保太陽(yang)能(neng)(neng)(neng)板組(zu)件輸出(chu)電(dian)(dian)(dian)(dian)壓始終達到設定(ding)(ding)充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓。這(zhe)種方(fang)(fang)法雖然可以實現弱(ruo)(ruo)光(guang)(guang)充(chong)(chong)電(dian)(dian)(dian)(dian)， 但(dan)在組(zu)態變化(hua)的(de)(de)瞬間(jian)， 電(dian)(dian)(dian)(dian)路輸出(chu)電(dian)(dian)(dian)(dian)壓波動較(jiao)(jiao)(jiao)大， 影響(xiang)系(xi)統(tong)穩(wen)定(ding)(ding)性。此外， 由于(yu)采(cai)(cai)用(yong)(yong)(yong)(yong)繼(ji)(ji)電(dian)(dian)(dian)(dian)器(qi)控(kong)(kong)制， 繼(ji)(ji)電(dian)(dian)(dian)(dian)器(qi)的(de)(de)機械開關觸點在工作(zuo)較(jiao)(jiao)(jiao)長(chang)時間(jian)后容易磨損失靈甚至引(yin)起誤操作(zuo)。為了(le)有(you)效提高系(xi)統(tong)弱(ruo)(ruo)光(guang)(guang)充(chong)(chong)電(dian)(dian)(dian)(dian)能(neng)(neng)(neng)力， 本文采(cai)(cai)用(yong)(yong)(yong)(yong)超級(ji)電(dian)(dian)(dian)(dian)容器(qi)組(zu)及升降壓電(dian)(dian)(dian)(dian)路來(lai)(lai)實現弱(ruo)(ruo)光(guang)(guang)條件下有(you)效充(chong)(chong)電(dian)(dian)(dian)(dian)， 并采(cai)(cai)用(yong)(yong)(yong)(yong)UC3909 實現對膠體密封(feng)鉛酸(suan)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)智能(neng)(neng)(neng)化(hua)充(chong)(chong)電(dian)(dian)(dian)(dian)管理， 延(yan)長(chang)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)使(shi)用(yong)(yong)(yong)(yong)壽命(ming)(ming)。

　　1  鉛酸蓄電池充電特性

　　鉛酸蓄電池的(de)充(chong)(chong)電特性是由其(qi)最(zui)大接受(shou)充(chong)(chong)電能力來體(ti)現， 是在保證蓄電池析氣率(lv)較低、溫升較低時所能承(cheng)受(shou)的(de)最(zui)大充(chong)(chong)電電流。其(qi)充(chong)(chong)電特性曲線方程式為：

       式中， I 為充(chong)電(dian)電(dian)流(liu)； I 0為初始最(zui)大充(chong)電(dian)電(dian)流(liu)； a 為最(zui)大接(jie)受力比(bi)； t 為充(chong)電(dian)時(shi)間。

　　在(zai)實(shi)際(ji)的電(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)管(guan)理(li)過(guo)程中， 要使(shi)蓄(xu)電(dian)(dian)(dian)池(chi)的充電(dian)(dian)(dian)過(guo)程完全吻合該(gai)充電(dian)(dian)(dian)特性曲線存在(zai)較大困難(nan)。因(yin)此本(ben)著提高(gao)充電(dian)(dian)(dian)效(xiao)率(lv)、保障(zhang)蓄(xu)電(dian)(dian)(dian)池(chi)使(shi)用壽命、實(shi)現(xian)合理(li)有(you)效(xiao)充電(dian)(dian)(dian)的原則，           參考充電(dian)(dian)(dian)特性曲線， 采用智能控(kong)制(zhi)芯片UC3909 實(shi)現(xian)對膠體密封鉛酸蓄(xu)電(dian)(dian)(dian)池(chi)分段充放電(dian)(dian)(dian)控(kong)制(zhi)管(guan)理(li)。

　　2  基于UC3909 控制器的四階段充電

　　目前獨立型太陽能照明系統中蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)控制器一般采用(yong)的(de)(de)是三階段(duan)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)，即先恒(heng)(heng)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)、再(zai)恒(heng)(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)、后浮充(chong)(chong)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。但(dan)由于某(mou)些應用(yong)場合(he)的(de)(de)蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)會經(jing)常出(chu)現(xian)過度(du)放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)情況， 如果一開始就直(zhi)接進入較大電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)恒(heng)(heng)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)階段(duan)， 容(rong)易造(zao)成熱失控， 易損壞蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)。所(suo)以(yi)在最開始的(de)(de)時候應該采用(yong)小電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)IT 充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)涓(juan)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)模(mo)式(shi)， 等蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)端電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)達到設定的(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)使能電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)UT 時， 再(zai)進行恒(heng)(heng)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。UC3909 芯片可(ke)以(yi)根據蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)狀態(tai)實(shi)現(xian)涓(juan)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)、恒(heng)(heng)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)、恒(heng)(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)和浮充(chong)(chong)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)四個階段(duan)合(he)理充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)， 如圖1 所(suo)示。

                                                                                         圖1  UC3909 的(de)四(si)階段充電曲線(xian)

　　狀態1: 涓流充電。

　　當蓄電池電壓低于充電使能電壓UT , 充電器提供很小的涓流IT 進行充(chong)電， IT 一般約為(wei)0. 01C（ C 為(wei)蓄(xu)電池容量）狀態2: 恒流充(chong)電。

　　當(dang)蓄(xu)電(dian)(dian)(dian)池的(de)電(dian)(dian)(dian)壓(ya)達(da)到充電(dian)(dian)(dian)使能電(dian)(dian)(dian)壓(ya)UT 時， 充電(dian)(dian)(dian)器(qi)提(ti)供(gong)一(yi)個大(da)電(dian)(dian)(dian)流I BULK 對(dui)蓄(xu)電(dian)(dian)(dian)池進行恒流充電(dian)(dian)(dian)， 這(zhe)一(yi)階段是充電(dian)(dian)(dian)的(de)主要階段， 蓄(xu)電(dian)(dian)(dian)池端(duan)電(dian)(dian)(dian)壓(ya)上升很快， 直至電(dian)(dian)(dian)壓(ya)上升到過壓(ya)充電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)UOC 時進入恒壓(ya)充電(dian)(dian)(dian)階段。

　　狀態3: 恒壓充電。

　　在此階段， 充(chong)(chong)(chong)電(dian)(dian)器提(ti)供一個略高于蓄(xu)電(dian)(dian)池(chi)額定值的(de)電(dian)(dian)壓(ya)UOC進行恒壓(ya)充(chong)(chong)(chong)電(dian)(dian)， 電(dian)(dian)路的(de)充(chong)(chong)(chong)電(dian)(dian)電(dian)(dian)流(liu)將按指(zhi)數規律逐漸(jian)減小， 直至(zhi)電(dian)(dian)流(liu)大小等于充(chong)(chong)(chong)電(dian)(dian)終止電(dian)(dian)流(liu)I OCT（約為10 % IBULK ） , 蓄(xu)電(dian)(dian)池(chi)已被充(chong)(chong)(chong)滿， 充(chong)(chong)(chong)電(dian)(dian)器進入浮(fu)充(chong)(chong)(chong)充(chong)(chong)(chong)電(dian)(dian)狀態(tai)。

　　狀態4: 浮充充電。

　　浮(fu)充(chong)(chong)(chong)(chong)充(chong)(chong)(chong)(chong)電(dian)(dian)階段， 充(chong)(chong)(chong)(chong)電(dian)(dian)器提供浮(fu)充(chong)(chong)(chong)(chong)電(dian)(dian)壓UF 對蓄電(dian)(dian)池以很小的(de)浮(fu)充(chong)(chong)(chong)(chong)電(dian)(dian)流進(jin)(jin)行充(chong)(chong)(chong)(chong)電(dian)(dian)， 以彌補蓄電(dian)(dian)池自放電(dian)(dian)造成的(de)容(rong)量損失。同時由于蓄電(dian)(dian)池的(de)浮(fu)充(chong)(chong)(chong)(chong)電(dian)(dian)壓隨溫(wen)(wen)度(du)變(bian)化而變(bian)化， 因此(ci)需要選(xuan)擇與蓄電(dian)(dian)池相同溫(wen)(wen)度(du)系(xi)(xi)數(shu)的(de)熱敏電(dian)(dian)阻進(jin)(jin)行溫(wen)(wen)度(du)補償， 確保(bao)在(zai)任(ren)何溫(wen)(wen)度(du)下都能以精確的(de)浮(fu)充(chong)(chong)(chong)(chong)電(dian)(dian)壓進(jin)(jin)行浮(fu)充(chong)(chong)(chong)(chong)充(chong)(chong)(chong)(chong)電(dian)(dian)。溫(wen)(wen)度(du)系(xi)(xi)數(shu)一般選(xuan)擇- 3. 5~ - 5 mV/ .

　　3  充電電路設計

　　圖2 所示為基于U C3909 太陽能蓄電池充電器電(dian)(dian)(dian)路框圖， 光伏陣(zhen)列經過(guo)電(dian)(dian)(dian)壓電(dian)(dian)(dian)流采樣再經模數轉換(huan)(huan)將數字信號(hao)反(fan)饋至單片機， 單片機根據(ju)光伏陣(zhen)列的工作狀況輸(shu)出PWM 信號(hao)去(qu)驅動PMOS 管， 實現(xian)對光伏陣(zhen)列的最(zui)大(da)功率跟蹤。超(chao)級(ji)電(dian)(dian)(dian)容器(qi)(qi)組、DC/ DC 變換(huan)(huan)器(qi)(qi)、UC3909 用(yong)來實現(xian)對閥控鉛酸蓄(xu)電(dian)(dian)(dian)池(chi)的四階段(duan)充(chong)電(dian)(dian)(dian)控制， 并利用(yong)超(chao)級(ji)電(dian)(dian)(dian)容的特性優化(hua)充(chong)放電(dian)(dian)(dian)過(guo)程(cheng)。本文側重對超(chao)級(ji)電(dian)(dian)(dian)容器(qi)(qi)組、U C3909 及DC/ DC 變換(huan)(huan)器(qi)(qi)等(deng)部分實現(xian)對閥控鉛酸蓄(xu)電(dian)(dian)(dian)池(chi)四階段(duan)的充(chong)電(dian)(dian)(dian)分析及設(she)計。

圖2  系(xi)統(tong)框圖

　　3. 1  UC3909 充電(dian)器主要參數設計(ji)

　　基(ji)于UC3909 的充放電(dian)(dian)電(dian)(dian)路如圖3 所示。

      圖3  基于UC3909的充放(fang)電電路

　　根(gen)據(ju)UC3909 內部(bu)集(ji)成電(dian)(dian)(dian)(dian)路及(ji)光伏陣列、超(chao)級電(dian)(dian)(dian)(dian)容參(can)(can)數并結合閥控鉛酸蓄(xu)電(dian)(dian)(dian)(dian)池的容量及(ji)額定電(dian)(dian)(dian)(dian)壓等參(can)(can)數對電(dian)(dian)(dian)(dian)路各個部(bu)分進行合理(li)計(ji)算設(she)計(ji)。本(ben)設(she)計(ji)使用賽特公(gong)司生產的12 V, 65 Ah膠體密封鉛酸蓄(xu)電(dian)(dian)(dian)(dian)池， 根(gen)據(ju)廠家提供的蓄(xu)電(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)參(can)(can)數， 浮充(chong)電(dian)(dian)(dian)(dian)壓UF 取(qu)(qu)13. 8 V,充(chong)電(dian)(dian)(dian)(dian)使能電(dian)(dian)(dian)(dian)壓UT 取(qu)(qu)10. 8 V; 過壓充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓UOC 14. 7V; 涓流(liu)(liu)充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)(liu)I TC 取(qu)(qu)0. 26 A; 恒(heng)流(liu)(liu)充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)(liu)I BU LK 取(qu)(qu)系統最大充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)(liu)6. 5 A; 過充(chong)終止電(dian)(dian)(dian)(dian)流(liu)(liu)IOCT 取(qu)(qu)1 A.

　　根據以上廠(chang)家所提供(gong)的蓄電(dian)池(chi)參數(shu)， 參照UC3909 芯片資料及相(xiang)關參考(kao)文(wen)獻，計算(suan)U C3909 外圍(wei)元件參數(shu)， R S1、RS2 、RS3、RS4計算(suan)公(gong)式如下(xia)：

　　式(shi)中， UREF 為UC3909 內部基準(zhun)電壓2. 3 V.代(dai)入相(xiang)關值(zhi)計算得（ R S1、RS2、RS3、RS4 分別為245 k Ω 、16 kΩ  、53kΩ 、975 kΩ 。

　　另外， 可(ke)以根據流(liu)(liu)入U C3909 內部電(dian)流(liu)(liu)誤差放大器反向輸出端CA 的固定控制電(dian)流(liu)(liu)ITRCK 、涓流(liu)(liu)充(chong)電(dian)電(dian)流(liu)(liu)I T 、恒流(liu)(liu)充(chong)電(dian)電(dian)流(liu)(liu)IBULK及過充(chong)終止電(dian)流(liu)(liu)IOCT 計算(suan)得出RG1、RG2 , R OVC1和ROVC2 , 其基本計算(suan)公(gong)式(shi)如下(xia)：

　　RSET 取11. 5 k  , 電流采樣(yang)電阻RS 取55 m  , 代入式（ 5）、（ 6） 得(de)：

ROVC1和R OVC2滿足以下關系(xi)式:

　　最終ROVC1和ROVC2 分別選取為1 k Ω  , 10 kΩ