近年來隨著能(neng)(neng)源(yuan)短(duan)缺問題日益突出， 太陽能(neng)(neng)、風能(neng)(neng)等新型無污染的(de)替代能(neng)(neng)源(yuan)應用日益受到重視。獨(du)立(li)型太陽能(neng)(neng)照明系統(tong)因(yin)其結構簡單、無需鋪(pu)設電纜， 且搭建、攜帶(dai)較為方(fang)便等特點在照明領域(yu)有著廣泛應用前景。

　　但目前急(ji)需解(jie)決(jue)的有鉛酸蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)使(shi)用(yong)(yong)壽命(ming)較短及系(xi)統在弱(ruo)(ruo)光(guang)條(tiao)件(jian)下(xia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)能(neng)(neng)(neng)力不足這兩大問題。系(xi)統儲能(neng)(neng)(neng)元件(jian)鉛酸蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)設計壽命(ming)約三(san)年(nian)， 但由于充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)方(fang)式、存儲方(fang)式以及人為等諸多(duo)因素的影響(xiang)(xiang)導(dao)(dao)致其使(shi)用(yong)(yong)壽命(ming)過(guo)短，需要經常更換， 不僅加大了(le)使(shi)用(yong)(yong)成本也影響(xiang)(xiang)了(le)系(xi)統的穩定性。另外(wai)大部分已使(shi)用(yong)(yong)的系(xi)統在弱(ruo)(ruo)光(guang)條(tiao)件(jian)下(xia)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)能(neng)(neng)(neng)力不足， 導(dao)(dao)致系(xi)統太陽能(neng)(neng)(neng)板利(li)用(yong)(yong)率(lv)不高(gao)； 傳統提高(gao)弱(ruo)(ruo)光(guang)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)能(neng)(neng)(neng)力的方(fang)法是采(cai)用(yong)(yong)組態優化控制來實(shi)現， 即根(gen)據外(wai)界光(guang)照強弱(ruo)(ruo)采(cai)用(yong)(yong)繼電(dian)(dian)(dian)器(qi)控制太陽能(neng)(neng)(neng)板組件(jian)按(an)照串聯或并聯等不同的組合方(fang)式給蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)， 確保太陽能(neng)(neng)(neng)板組件(jian)輸出(chu)電(dian)(dian)(dian)壓始終達到(dao)設定充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓。這種(zhong)方(fang)法雖然(ran)可以實(shi)現弱(ruo)(ruo)光(guang)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)， 但在組態變化的瞬間， 電(dian)(dian)(dian)路(lu)輸出(chu)電(dian)(dian)(dian)壓波動(dong)較大， 影響(xiang)(xiang)系(xi)統穩定性。此外(wai)， 由于采(cai)用(yong)(yong)繼電(dian)(dian)(dian)器(qi)控制， 繼電(dian)(dian)(dian)器(qi)的機械開關觸點在工作(zuo)較長(chang)時間后容(rong)易磨(mo)損失(shi)靈甚至(zhi)引起誤操作(zuo)。為了(le)有效提高(gao)系(xi)統弱(ruo)(ruo)光(guang)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)能(neng)(neng)(neng)力， 本文采(cai)用(yong)(yong)超(chao)級電(dian)(dian)(dian)容(rong)器(qi)組及升降壓電(dian)(dian)(dian)路(lu)來實(shi)現弱(ruo)(ruo)光(guang)條(tiao)件(jian)下(xia)有效充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)， 并采(cai)用(yong)(yong)UC3909 實(shi)現對(dui)膠體密(mi)封(feng)鉛酸蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)智能(neng)(neng)(neng)化充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)管理， 延長(chang)蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)使(shi)用(yong)(yong)壽命(ming)。

　　1  鉛酸蓄電池充電特性

　　鉛酸蓄電(dian)池的(de)充(chong)(chong)電(dian)特性是(shi)由(you)其最大(da)接受(shou)充(chong)(chong)電(dian)能力來體現， 是(shi)在保(bao)證(zheng)蓄電(dian)池析氣率較(jiao)低、溫升(sheng)較(jiao)低時所能承受(shou)的(de)最大(da)充(chong)(chong)電(dian)電(dian)流(liu)。其充(chong)(chong)電(dian)特性曲線方程式為：

       式中(zhong)， I 為充電(dian)電(dian)流； I 0為初(chu)始最大充電(dian)電(dian)流； a 為最大接(jie)受力比； t 為充電(dian)時間(jian)。

　　在(zai)實(shi)際(ji)的(de)電(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)管理過(guo)程(cheng)中， 要使(shi)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)的(de)充(chong)電(dian)(dian)(dian)(dian)過(guo)程(cheng)完全(quan)吻(wen)合該(gai)充(chong)電(dian)(dian)(dian)(dian)特性曲(qu)線存在(zai)較大困難。因此本(ben)著提高充(chong)電(dian)(dian)(dian)(dian)效率(lv)、保障蓄(xu)電(dian)(dian)(dian)(dian)池(chi)使(shi)用(yong)壽命、實(shi)現合理有(you)效充(chong)電(dian)(dian)(dian)(dian)的(de)原則(ze)，           參考(kao)充(chong)電(dian)(dian)(dian)(dian)特性曲(qu)線， 采用(yong)智能控制芯片UC3909 實(shi)現對膠(jiao)體密封(feng)鉛酸(suan)蓄(xu)電(dian)(dian)(dian)(dian)池(chi)分段充(chong)放電(dian)(dian)(dian)(dian)控制管理。

　　2  基于UC3909 控制器的四階段充電

　　目前獨立型太陽能(neng)照明(ming)系(xi)統中(zhong)蓄(xu)電(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)控制(zhi)器一(yi)(yi)般采(cai)(cai)用(yong)的(de)是三階段(duan)充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)方式(shi)，即(ji)先恒(heng)(heng)流充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)、再恒(heng)(heng)壓充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)、后浮充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)。但由于(yu)某些應用(yong)場合的(de)蓄(xu)電(dian)(dian)(dian)(dian)(dian)池(chi)會經常出現(xian)過度放電(dian)(dian)(dian)(dian)(dian)的(de)情況， 如果一(yi)(yi)開(kai)始就直(zhi)接進(jin)入較大電(dian)(dian)(dian)(dian)(dian)流充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)的(de)恒(heng)(heng)流充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)階段(duan)， 容易造成熱失控， 易損壞蓄(xu)電(dian)(dian)(dian)(dian)(dian)池(chi)。所以(yi)在最開(kai)始的(de)時(shi)候應該(gai)采(cai)(cai)用(yong)小電(dian)(dian)(dian)(dian)(dian)流IT 充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)的(de)涓(juan)流充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)模式(shi)， 等(deng)蓄(xu)電(dian)(dian)(dian)(dian)(dian)池(chi)的(de)端電(dian)(dian)(dian)(dian)(dian)壓達(da)到設定的(de)充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)使能(neng)電(dian)(dian)(dian)(dian)(dian)壓UT 時(shi)， 再進(jin)行恒(heng)(heng)流充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)。UC3909 芯片可以(yi)根據蓄(xu)電(dian)(dian)(dian)(dian)(dian)池(chi)的(de)狀態實現(xian)涓(juan)流充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)、恒(heng)(heng)流充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)、恒(heng)(heng)壓充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)和浮充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)四個階段(duan)合理(li)充(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)， 如圖1 所示。

                                                                                         圖(tu)1  UC3909 的四階段充電(dian)曲線

　　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(liu)IT 進行充電， IT 一般約為0. 01C（ C 為蓄電池容量）狀態(tai)2: 恒流(liu)充電。

　　當蓄(xu)電(dian)(dian)池的電(dian)(dian)壓(ya)(ya)達到充(chong)(chong)電(dian)(dian)使(shi)能電(dian)(dian)壓(ya)(ya)UT 時， 充(chong)(chong)電(dian)(dian)器提供一(yi)個大電(dian)(dian)流I BULK 對蓄(xu)電(dian)(dian)池進行(xing)恒(heng)流充(chong)(chong)電(dian)(dian)， 這一(yi)階段(duan)是充(chong)(chong)電(dian)(dian)的主(zhu)要階段(duan)， 蓄(xu)電(dian)(dian)池端電(dian)(dian)壓(ya)(ya)上升(sheng)(sheng)很快， 直至電(dian)(dian)壓(ya)(ya)上升(sheng)(sheng)到過(guo)壓(ya)(ya)充(chong)(chong)電(dian)(dian)電(dian)(dian)壓(ya)(ya)UOC 時進入恒(heng)壓(ya)(ya)充(chong)(chong)電(dian)(dian)階段(duan)。

　　狀態3: 恒壓充電。

　　在(zai)此階段， 充(chong)(chong)電(dian)(dian)器提供一個(ge)略(lve)高于蓄電(dian)(dian)池(chi)額定值的電(dian)(dian)壓UOC進(jin)行恒(heng)壓充(chong)(chong)電(dian)(dian)， 電(dian)(dian)路的充(chong)(chong)電(dian)(dian)電(dian)(dian)流(liu)將(jiang)按指(zhi)數規律逐漸減小， 直(zhi)至電(dian)(dian)流(liu)大小等于充(chong)(chong)電(dian)(dian)終止電(dian)(dian)流(liu)I OCT（約(yue)為10 % IBULK ） , 蓄電(dian)(dian)池(chi)已被充(chong)(chong)滿， 充(chong)(chong)電(dian)(dian)器進(jin)入浮充(chong)(chong)充(chong)(chong)電(dian)(dian)狀態。

　　狀態4: 浮充充電。

　　浮充(chong)(chong)充(chong)(chong)電(dian)(dian)(dian)(dian)階段， 充(chong)(chong)電(dian)(dian)(dian)(dian)器提(ti)供浮充(chong)(chong)電(dian)(dian)(dian)(dian)壓UF 對蓄(xu)電(dian)(dian)(dian)(dian)池以很(hen)小(xiao)的(de)(de)(de)浮充(chong)(chong)電(dian)(dian)(dian)(dian)流(liu)進行(xing)(xing)充(chong)(chong)電(dian)(dian)(dian)(dian)， 以彌補蓄(xu)電(dian)(dian)(dian)(dian)池自放(fang)電(dian)(dian)(dian)(dian)造成的(de)(de)(de)容量損失。同時由于蓄(xu)電(dian)(dian)(dian)(dian)池的(de)(de)(de)浮充(chong)(chong)電(dian)(dian)(dian)(dian)壓隨溫(wen)(wen)度(du)(du)變化而變化， 因此(ci)需要選擇(ze)與蓄(xu)電(dian)(dian)(dian)(dian)池相(xiang)同溫(wen)(wen)度(du)(du)系數(shu)的(de)(de)(de)熱敏電(dian)(dian)(dian)(dian)阻進行(xing)(xing)溫(wen)(wen)度(du)(du)補償， 確保(bao)在任何溫(wen)(wen)度(du)(du)下都能以精確的(de)(de)(de)浮充(chong)(chong)電(dian)(dian)(dian)(dian)壓進行(xing)(xing)浮充(chong)(chong)充(chong)(chong)電(dian)(dian)(dian)(dian)。溫(wen)(wen)度(du)(du)系數(shu)一(yi)般(ban)選擇(ze)- 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)(dian)路框圖(tu)， 光(guang)伏陣列(lie)經(jing)過電(dian)(dian)(dian)(dian)壓電(dian)(dian)(dian)(dian)流采樣(yang)再經(jing)模數(shu)轉換將(jiang)數(shu)字信號反(fan)饋至單片機， 單片機根據光(guang)伏陣列(lie)的工(gong)作狀況輸出PWM 信號去驅動PMOS 管， 實現對光(guang)伏陣列(lie)的最大(da)功率跟蹤。超(chao)級(ji)電(dian)(dian)(dian)(dian)容(rong)器組(zu)、DC/ DC 變換器、UC3909 用(yong)(yong)來實現對閥控(kong)鉛(qian)酸蓄電(dian)(dian)(dian)(dian)池的四階段充(chong)電(dian)(dian)(dian)(dian)控(kong)制(zhi)， 并(bing)利用(yong)(yong)超(chao)級(ji)電(dian)(dian)(dian)(dian)容(rong)的特性(xing)優化充(chong)放電(dian)(dian)(dian)(dian)過程。本(ben)文側重對超(chao)級(ji)電(dian)(dian)(dian)(dian)容(rong)器組(zu)、U C3909 及DC/ DC 變換器等部分實現對閥控(kong)鉛(qian)酸蓄電(dian)(dian)(dian)(dian)池四階段的充(chong)電(dian)(dian)(dian)(dian)分析及設計。

圖2  系(xi)統框圖

　　3. 1  UC3909 充(chong)電器(qi)主要(yao)參(can)數設計

　　基于UC3909 的充放電(dian)電(dian)路(lu)如圖3 所示。

      圖(tu)3  基(ji)于UC3909的(de)充(chong)放電(dian)電(dian)路

　　根據(ju)UC3909 內部集成電(dian)路(lu)(lu)及光伏陣列、超級電(dian)容參數(shu)并結合(he)閥控鉛酸(suan)蓄(xu)電(dian)池(chi)的容量及額定電(dian)壓(ya)等參數(shu)對電(dian)路(lu)(lu)各個部分進行合(he)理計算設計。本設計使用賽特公司生產(chan)的12 V, 65 Ah膠體(ti)密(mi)封鉛酸(suan)蓄(xu)電(dian)池(chi)， 根據(ju)廠(chang)家(jia)提供的蓄(xu)電(dian)池(chi)充(chong)(chong)(chong)電(dian)參數(shu)， 浮充(chong)(chong)(chong)電(dian)壓(ya)UF 取(qu)13. 8 V,充(chong)(chong)(chong)電(dian)使能電(dian)壓(ya)UT 取(qu)10. 8 V; 過(guo)壓(ya)充(chong)(chong)(chong)電(dian)電(dian)壓(ya)UOC 14. 7V; 涓流(liu)充(chong)(chong)(chong)電(dian)電(dian)流(liu)I TC 取(qu)0. 26 A; 恒流(liu)充(chong)(chong)(chong)電(dian)電(dian)流(liu)I BU LK 取(qu)系統最大充(chong)(chong)(chong)電(dian)電(dian)流(liu)6. 5 A; 過(guo)充(chong)(chong)(chong)終止電(dian)流(liu)IOCT 取(qu)1 A.

　　根據以上廠(chang)家所提(ti)供的(de)蓄電池參(can)數， 參(can)照(zhao)UC3909 芯片(pian)資料及相關參(can)考文獻，計(ji)算(suan)U C3909 外(wai)圍元件參(can)數， R S1、RS2 、RS3、RS4計(ji)算(suan)公式如(ru)下(xia)：

　　式中(zhong)， UREF 為UC3909 內(nei)部基準電壓2. 3 V.代入相關值計算得（ R S1、RS2、RS3、RS4 分別為245 k Ω 、16 kΩ  、53kΩ 、975 kΩ 。

　　另(ling)外， 可以根(gen)據流入U C3909 內(nei)部電(dian)(dian)(dian)流誤差放大器反向輸出端CA 的固定控制電(dian)(dian)(dian)流ITRCK 、涓流充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流I T 、恒(heng)流充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流IBULK及過充(chong)終止電(dian)(dian)(dian)流IOCT 計(ji)算得(de)出RG1、RG2 , R OVC1和ROVC2 , 其(qi)基本計(ji)算公(gong)式(shi)如(ru)下：

　　RSET 取11. 5 k  , 電(dian)流采樣電(dian)阻RS 取55 m  , 代入式（ 5）、（ 6） 得(de)：

ROVC1和R OVC2滿足以下關系式:

　　最終(zhong)ROVC1和ROVC2 分別選取(qu)為(wei)1 k Ω  , 10 kΩ