在研究電動車用蓄電池特性及其充電策略和充電算法的基礎上，研制了一款基于P IC16C712單片機的4段式（涓流短時充電、恒流快速充電、恒壓均衡充電、浮充電） 48V （20A?h）蓄電池充電器。該(gai)充(chong)(chong)電(dian)器能夠對(dui)充(chong)(chong)電(dian)過程進行實時監測與控(kong)制(zhi)，使充(chong)(chong)電(dian)過程按設定(ding)的(de)理想充(chong)(chong)電(dian)曲線進行。測試表(biao)明，該(gai)充(chong)(chong)電(dian)器既能完成快速(su)充(chong)(chong)電(dian)又(you)能對(dui)蓄電(dian)池進行有效的(de)保(bao)護。

　　近年來，電(dian)動車作為(wei)一種新型的(de)(de)綠色交通工具得到了迅猛的(de)(de)發展(zhan)，并(bing)呈(cheng)現出向(xiang)大功率、高(gao)速化和功能(neng)多(duo)(duo)樣化的(de)(de)發展(zhan)趨(qu)勢。因此，電(dian)動車對蓄電(dian)池(chi)的(de)(de)使用(yong)壽命、續(xu)行(xing)里程等性(xing)(xing)能(neng)提出的(de)(de)要(yao)求比以往更加(jia)苛刻。實驗研究表明：影響蓄電(dian)池(chi)性(xing)(xing)能(neng)的(de)(de)因素多(duo)(duo)種多(duo)(duo)樣，如電(dian)動車的(de)(de)裝配性(xing)(xing)能(neng)、行(xing)駛電(dian)流(liu)、充電(dian)策略等。

　　其(qi)中(zhong)蓄(xu)電(dian)池的(de)充(chong)電(dian)過程對(dui)其(qi)壽命影響(xiang)最大，過充(chong)電(dian)、充(chong)電(dian)不足是(shi)引起蓄(xu)電(dian)池故障的(de)主要(yao)原因(yin)。所以，必須(xu)通過設計合理的(de)充(chong)電(dian)策(ce)略(lve)和充(chong)電(dian)算法以有效地減少(shao)蓄(xu)電(dian)池的(de)損傷、減少(shao)充(chong)電(dian)損耗、提高充(chong)電(dian)速度。

　　為此，開發一種具有自主知識產權，具備適用功率大（ 100 ~500W ） 、性能可靠等特點的電動車用48V （20A?h）蓄電池充電器以滿足電動摩托車、卡丁車、沙地車等電動車發展的迫切需要。該充電器以P IC16C712作為實時監控和中心控制單元，采用PWM DC-DC全橋變換器作為主電路，使得該充電器能夠根據蓄電池的充電特性自動調節輸出電壓、電流，進行智能充電，并且能夠對充電器的運行狀態進行實時(shi)監測，若有(you)異常，能(neng)及時(shi)地進行保護(hu)。此外，該充電器還具(ju)有(you)體積(ji)小、重量輕、精度(du)高、充電速(su)度(du)快、性(xing)能(neng)穩定等(deng)顯著(zhu)優點。

　　1 充電器(qi)原理與硬(ying)件設(she)計

　　1. 1 總體設計

　　目(mu)前，電(dian)(dian)動車電(dian)(dian)池(chi)作為(wei)(wei)一種儲能(neng)裝置，主要以(yi)鉛(qian)酸(suan)蓄(xu)(xu)電(dian)(dian)池(chi)為(wei)(wei)主，充(chong)(chong)電(dian)(dian)器是專門針對鉛(qian)酸(suan)蓄(xu)(xu)電(dian)(dian)池(chi)所(suo)設計的(de)(de)。傳統的(de)(de)蓄(xu)(xu)電(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)器采用電(dian)(dian)流(liu)/電(dian)(dian)壓負反饋的(de)(de)方(fang)法來達到恒(heng)流(liu)/恒(heng)壓充(chong)(chong)電(dian)(dian)的(de)(de)目(mu)的(de)(de)，為(wei)(wei)了實現充(chong)(chong)電(dian)(dian)過程(cheng)各種工(gong)作參量的(de)(de)實時監測及智能(neng)多段(duan)式充(chong)(chong)電(dian)(dian)策略的(de)(de)精確(que)控(kong)(kong)制，引入電(dian)(dian)流(liu)/電(dian)(dian)壓反饋環，應用P IC16C712 單(dan)片機及相應的(de)(de)控(kong)(kong)制電(dian)(dian)路，其硬件結構框圖如圖1所(suo)示，電(dian)(dian)路圖如圖2所(suo)示。

圖1 硬件(jian)結構框圖

圖(tu)2 電路(lu)原理圖(tu)

　

　由圖1和(he)圖2可以看出，蓄(xu)電(dian)(dian)池充電(dian)(dian)器(qi)主要由開關電(dian)(dian)源單元（電(dian)(dian)源變壓器(qi)、整流電(dian)(dian)路(lu)及濾波電(dian)(dian)路(lu)）和(he)監測與控制(zhi)單元（傳(chuan)感(gan)器(qi)、電(dian)(dian)源專用集成(cheng)芯片UC3875及微控制(zhi)器(qi)P IC16C712）兩部分組(zu)成(cheng)。

在開關電源單元，單相220V /50Hz的(de)交(jiao)流(liu)電需經(jing)過(guo)全橋整流(liu)及(ji)大電容低頻濾(lv)(lv)波(bo)穩壓，然后(hou)經(jing)過(guo)4只IGBT器(qi)件IGBTl ~ IGBT4 組(zu)成的(de)全橋逆變器(qi)可(ke)得到脈寬可(ke)調的(de)高頻交(jiao)流(liu)電。經(jing)高頻變壓器(qi)耦合(he)到副邊，再經(jing)整流(liu)管D9 和D10整流(liu)和電感L2、電容C5 濾(lv)(lv)波(bo)，由此(ci)可(ke)以得到大小可(ke)變的(de)低紋波(bo)直流(liu)電壓。

　　根據實際需(xu)要，監測(ce)與控(kong)制單元選(xuan)擇的(de)(de)單片機型(xing)號(hao)(hao)是(shi)由(you)M ICROCH IP公司推出的(de)(de)P IC16C712,其內(nei)部有(you)容(rong)量為1KB ×14 的(de)(de)EPROM、128 ×8 的(de)(de)RAM,此外，還包括4個8位A /D, 3個定時器和1個CCP模塊。充電器的(de)(de)電壓和電流控(kong)制信(xin)號(hao)(hao)是(shi)由(you)P IC16C712的(de)(de)CCP模塊輸(shu)(shu)(shu)出，經過F /V轉換之后輸(shu)(shu)(shu)入到(dao)由(you)美國Unitrode公司生產的(de)(de)移(yi)相式開關(guan)電源專(zhuan)用集成芯片UC3875的(de)(de)誤差放(fang)大器輸(shu)(shu)(shu)入端E /A + ,反相輸(shu)(shu)(shu)入端E /A - 接主電路輸(shu)(shu)(shu)出直流電流或直流電壓反饋(kui)信(xin)號(hao)(hao)，二者之間的(de)(de)切換由(you)P IC16C712單片機控(kong)制中間繼電器實現(xian)。

　　1. 2 溫度信(xin)號(hao)采(cai)集電(dian)路

　　在(zai)充電(dian)(dian)過(guo)程中，蓄(xu)電(dian)(dian)池(chi)的溫度(du)(du)是一(yi)個非常重要的參數。因為(wei)鉛酸(suan)蓄(xu)電(dian)(dian)池(chi)的電(dian)(dian)壓(ya)具有負溫度(du)(du)系(xi)數，其值為(wei)- 4mV /℃，對(dui)于一(yi)個在(zai)環(huan)境(jing)溫度(du)(du)為(wei)25℃時工作很(hen)理想的充電(dian)(dian)器在(zai)環(huan)境(jing)溫度(du)(du)降到0℃時，蓄(xu)電(dian)(dian)池(chi)將出(chu)現(xian)充電(dian)(dian)不足的現(xian)象；而當環(huan)境(jing)溫度(du)(du)升(sheng)高(gao)到50℃時，蓄(xu)電(dian)(dian)池(chi)將出(chu)現(xian)過(guo)充電(dian)(dian)的現(xian)象，這(zhe)將導致蓄(xu)電(dian)(dian)池(chi)壽(shou)命縮短。

　　因此，設計良(liang)好的充電(dian)器應(ying)(ying)具有(you)溫(wen)度檢測功(gong)能并(bing)(bing)能夠根據(ju)不同的環境溫(wen)度調整充電(dian)過程中的各轉換電(dian)壓值；同時，充電(dian)器還應(ying)(ying)具備溫(wen)度保護功(gong)能，在充電(dian)過程中，當(dang)蓄電(dian)池溫(wen)度超出限定(ding)的溫(wen)度范(fan)圍(wei)時充電(dian)器應(ying)(ying)立即停止充電(dian)或進(jin)入涓流充電(dian)，并(bing)(bing)且PIC16C712應(ying)(ying)點亮故障指示燈以提示用(yong)戶出現何種(zhong)異常。

　　由(you)上分析可知，溫(wen)度(du)(du)(du)檢測(ce)的準(zhun)確性將在很大程度(du)(du)(du)上影響充電器的性能。為此，利用(yong)LM61B IM3溫(wen)度(du)(du)(du)傳感器設(she)計(ji)了溫(wen)度(du)(du)(du)檢測(ce)電路(lu)，如圖3所示，該傳感器可以(yi)測(ce)量(liang)的溫(wen)度(du)(du)(du)范圍為- 25℃~ + 85℃，線性度(du)(du)(du)為10mV /℃，即：

圖3 溫度(du)采(cai)集電路(lu)圖

　

　2 充電策略與算法設(she)計(ji)

　　2. 1 充電流(liu)程

　　根據鉛酸蓄電(dian)(dian)(dian)池的(de)(de)特(te)點，將其充(chong)電(dian)(dian)(dian)過程分為(wei)4個階(jie)(jie)段：涓流短時(shi)充(chong)電(dian)(dian)(dian)、恒(heng)流快(kuai)速充(chong)電(dian)(dian)(dian)、恒(heng)壓(ya)(ya)均衡充(chong)電(dian)(dian)(dian)、浮充(chong)電(dian)(dian)(dian)。其中第一階(jie)(jie)段和第二(er)階(jie)(jie)段均為(wei)恒(heng)流充(chong)電(dian)(dian)(dian)，采(cai)取這種策(ce)略是因為(wei)實驗研究(jiu)證明(ming)多(duo)(duo)段恒(heng)流充(chong)電(dian)(dian)(dian)有利(li)于充(chong)入更多(duo)(duo)的(de)(de)電(dian)(dian)(dian)量且可以(yi)減(jian)少對蓄電(dian)(dian)(dian)池的(de)(de)損傷、延長(chang)使用壽命。充(chong)電(dian)(dian)(dian)過程中各(ge)個階(jie)(jie)段充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)(ya)、充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流隨時(shi)間變化的(de)(de)曲線如圖4所示。

圖4 充電流程曲線。

（1）涓流短時充電（ T0 - T1 ）
 

　　

       蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池在(zai)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)初期可能已處于(yu)深度放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)狀(zhuang)態（或可能已經處于(yu)受損(sun)的狀(zhuang)態） ,為避免對(dui)蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)過大造(zao)成"熱(re)失(shi)控", P IC16C712單(dan)片機通過實時監測(ce)蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池的電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，對(dui)蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池進行穩(wen)定的小電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)涓(juan)(juan)流(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，這樣有利于(yu)激活蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池內的反應物質，部(bu)分恢復受損(sun)的蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池單(dan)元(yuan)。在(zai)涓(juan)(juan)流(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)階段，蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)開始緩慢(man)上升(sheng)，當蓄(xu)(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)上升(sheng)到能接受大電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的閾值(zhi)時則轉入恒流(liu)快速充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)階段。

　　（2）恒流快速充(chong)電(dian)（ T1 - T2 ）

　　該階(jie)段充電電流(liu)保持恒定，蓄(xu)電池電壓(ya)上(shang)升較快，當(dang)電壓(ya)上(shang)升至均衡(heng)充電壓(ya)閾值時，則(ze)轉(zhuan)入恒壓(ya)均衡(heng)充電階(jie)段。

　　（3）恒壓均衡充電（ T2 - T3 ）

　　該(gai)階段充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)保持恒定，蓄電(dian)(dian)(dian)池容量快速恢(hui)復。充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)逐(zhu)漸減小，當電(dian)(dian)(dian)流(liu)下降至(zhi)某(mou)一(yi)閾值時，自動轉(zhuan)入浮充(chong)電(dian)(dian)(dian)階段。

　　（4）浮充電（ T3 - ）

　　該階段主要用來(lai)補充蓄電(dian)池自放電(dian)所消耗的能(neng)量，此時標志著充電(dian)過(guo)程(cheng)結束(shu)。

　　2. 2 關鍵技術

　　2. 2. 1 恒流充電電流的選擇(ze)

　　充(chong)電(dian)過程中包含兩個(ge)恒(heng)流(liu)充(chong)電(dian)過程：涓(juan)流(liu)短時充(chong)電(dian)和恒(heng)流(liu)快(kuai)速充(chong)電(dian)。

　　涓(juan)流短時充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流的選擇應該根據蓄電(dian)(dian)(dian)池(chi)的剩(sheng)余電(dian)(dian)(dian)量(liang)進行選擇。經過(guo)大(da)量(liang)的實驗研究表明(ming)，對于(yu)放電(dian)(dian)(dian)深度(du)為80% ~100%的蓄電(dian)(dian)(dian)池(chi)，充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流定在0. 2~0. 4A比較合適。

　　恒流快速充電(dian)(dian)電(dian)(dian)流的(de)(de)(de)選擇(ze)要(yao)綜合(he)(he)考慮(lv)蓄電(dian)(dian)池(chi)容(rong)量(liang)、內阻、對(dui)充電(dian)(dian)時(shi)(shi)間的(de)(de)(de)要(yao)求(qiu)、制造成本(ben)等多(duo)方面因素。按照應(ying)用經(jing)驗(yan)，普遍認為，該充電(dian)(dian)電(dian)(dian)流設置為0. 15~0. 3 C對(dui)蓄電(dian)(dian)池(chi)比較合(he)(he)適。電(dian)(dian)動自行車(che)用48V （20A?h）鉛酸蓄電(dian)(dian)池(chi)時(shi)(shi)采用的(de)(de)(de)是20℃標(biao)稱，但是實際容(rong)量(liang)往(wang)往(wang)只能達(da)到15~17A?h.因此，依據該經(jing)驗(yan)看法，充電(dian)(dian)電(dian)(dian)流應(ying)大致定在2. 25~5. 1 A之間，平(ping)均為3. 675A.

　　有設計者認為(wei)減小(xiao)充(chong)電(dian)(dian)電(dian)(dian)流具有3個方(fang)面的(de)優點： （1）可(ke)以(yi)(yi)(yi)使(shi)(shi)單位時間內產(chan)生(sheng)的(de)熱量降低(di)(di)，有利(li)于在蓄(xu)電(dian)(dian)池的(de)使(shi)(shi)用(yong)壽命末期和夏季保證充(chong)電(dian)(dian)質量；（2）可(ke)以(yi)(yi)(yi)減少極化(hua)(hua)（歐姆(mu)極化(hua)(hua)、濃(nong)差極化(hua)(hua)、電(dian)(dian)化(hua)(hua)學極化(hua)(hua)）現(xian)象的(de)影響，有利(li)于冬季充(chong)電(dian)(dian)； （ 3）可(ke)以(yi)(yi)(yi)降低(di)(di)充(chong)電(dian)(dian)器的(de)輸(shu)出功率，制(zhi)造成本下降。但是也有設計者認為(wei)，電(dian)(dian)動車用(yong)蓄(xu)電(dian)(dian)池以(yi)(yi)(yi)較大(da)(da)電(dian)(dian)流短時間放電(dian)(dian)，充(chong)電(dian)(dian)接受(shou)率高(gao)， 所(suo)以(yi)(yi)(yi)可(ke)以(yi)(yi)(yi)增大(da)(da)充(chong)電(dian)(dian)電(dian)(dian)流（甚至推(tui)薦為(wei)5A）以(yi)(yi)(yi)提高(gao)充(chong)電(dian)(dian)速度(du)。

　　通(tong)過(guo)對浙(zhe)江天能、浙(zhe)江超威、英國IBT和日本松(song)下等(deng)電(dian)動車用48V （ 20A?h）蓄電(dian)池進行了長期的可靠(kao)性(xing)實(shi)驗。在充(chong)(chong)電(dian)時，采用平均值(zhi)為3. 5A并根(gen)據環(huan)境溫(wen)度動態小幅度調整的恒流快(kuai)速充(chong)(chong)電(dian)電(dian)流，蓄電(dian)池沒有明顯發熱，充(chong)(chong)電(dian)過(guo)程穩定可靠(kao)。

　　2. 2. 2 恒(heng)壓充電電壓的選擇

　　恒(heng)壓(ya)充(chong)電電壓(ya)的(de)(de)選(xuan)擇非常關鍵(jian)，因為它(ta)不(bu)能(neng)在很寬的(de)(de)范圍(wei)內調(diao)整。確定(ding)這個參數不(bu)但需要對蓄電池有較為深人的(de)(de)了(le)解，還需要對充(chong)電策略等因素進行考(kao)慮。

　　蓄(xu)電(dian)(dian)(dian)池(chi)在(zai)充(chong)電(dian)(dian)(dian)時(shi)，正極(ji)上的析氧速率與(yu)施(shi)加的充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)(ya)成(cheng)正比，而(er)氧傳輸到(dao)負極(ji)并溶(rong)解在(zai)負極(ji)表面液膜中進行還(huan)原的速度受到(dao)限制，即(ji)氧的析出(chu)快(kuai)于(yu)(yu)還(huan)原時(shi)，復合效(xiao)率就下(xia)(xia)降(jiang)，造成(cheng)失水。通常(chang)情況下(xia)(xia)， 48V 閥控鉛(qian)酸蓄(xu)電(dian)(dian)(dian)池(chi)的浮(fu)充(chong)電(dian)(dian)(dian)壓(ya)(ya)設置在(zai)55 -55. 6 V,可以(yi)保證蓄(xu)電(dian)(dian)(dian)池(chi)長(chang)期處于(yu)(yu)充(chong)電(dian)(dian)(dian)狀態且(qie)極(ji)少失水。循環使(shi)用蓄(xu)電(dian)(dian)(dian)池(chi)最(zui)高充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)(ya)為(wei)58. 8V,如(ru)果超過就會(hui)使(shi)復合效(xiao)率急劇下(xia)(xia)降(jiang)，從(cong)而(er)影響電(dian)(dian)(dian)池(chi)的使(shi)用壽命(ming)。

　　2. 2. 3 蓄電池是否充滿的判定(ding)

　　對蓄(xu)(xu)(xu)電(dian)(dian)池在充(chong)(chong)電(dian)(dian)過程(cheng)中是(shi)(shi)否已充(chong)(chong)滿(man)的(de)判(pan)(pan)斷(duan)是(shi)(shi)充(chong)(chong)電(dian)(dian)器的(de)重要指標。如果蓄(xu)(xu)(xu)電(dian)(dian)池未(wei)充(chong)(chong)滿(man)而錯(cuo)判(pan)(pan)為充(chong)(chong)滿(man)將導致(zhi)蓄(xu)(xu)(xu)電(dian)(dian)池欠充(chong)(chong)；反之，則(ze)將導致(zhi)蓄(xu)(xu)(xu)電(dian)(dian)池過充(chong)(chong)。這兩種情(qing)況都(dou)會嚴(yan)重影響(xiang)蓄(xu)(xu)(xu)電(dian)(dian)池的(de)壽(shou)命。目前判(pan)(pan)斷(duan)蓄(xu)(xu)(xu)電(dian)(dian)池是(shi)(shi)否充(chong)(chong)滿(man)的(de)控(kong)制準(zhun)則(ze)有：定時控(kong)制、電(dian)(dian)壓(ya)控(kong)制（包(bao)含(han)最(zui)高電(dian)(dian)壓(ya)、電(dian)(dian)壓(ya)負增量(liang)、電(dian)(dian)壓(ya)零增量(liang)等(deng)(deng)）、溫(wen)度控(kong)制（包(bao)括(kuo)最(zui)高溫(wen)度、最(zui)高溫(wen)升、溫(wen)度變化率等(deng)(deng)）、電(dian)(dian)流控(kong)制（包(bao)含(han)最(zui)小電(dian)(dian)流、電(dian)(dian)流變化量(liang)等(deng)(deng)）、動態內阻控(kong)制等(deng)(deng)。

　　在(zai)(zai)實際應用(yong)中，如果以單一的(de)(de)(de)控制的(de)(de)(de)方式都將(jiang)不(bu)可(ke)避免地存在(zai)(zai)缺陷(xian)。比如，在(zai)(zai)恒(heng)壓均衡充電(dian)(dian)(dian)過(guo)程中，電(dian)(dian)(dian)壓保持恒(heng)定(ding)(ding)(ding)，電(dian)(dian)(dian)流(liu)會(hui)(hui)隨(sui)著充電(dian)(dian)(dian)的(de)(de)(de)進(jin)程逐漸減小，當(dang)小到一定(ding)(ding)(ding)程度(du)電(dian)(dian)(dian)流(liu)將(jiang)會(hui)(hui)恒(heng)定(ding)(ding)(ding)，不(bu)再下降，這(zhe)(zhe)時的(de)(de)(de)電(dian)(dian)(dian)能(neng)向化(hua)學(xue)能(neng)的(de)(de)(de)轉化(hua)效率已(yi)經很低，電(dian)(dian)(dian)能(neng)主要用(yong)于電(dian)(dian)(dian)解(jie)水(shui)，一般(ban)認為(wei)這(zhe)(zhe)個電(dian)(dian)(dian)流(liu)為(wei)蓄電(dian)(dian)(dian)池(chi)恒(heng)壓均衡充電(dian)(dian)(dian)的(de)(de)(de)殘(can)余(yu)(yu)電(dian)(dian)(dian)流(liu)。然而(er)(er)，殘(can)余(yu)(yu)電(dian)(dian)(dian)流(liu)的(de)(de)(de)大小將(jiang)隨(sui)著環(huan)境溫度(du)的(de)(de)(de)變(bian)化(hua)而(er)(er)變(bian)化(hua)，也就是(shi)說殘(can)余(yu)(yu)電(dian)(dian)(dian)流(liu)是(shi)一個受內、外(wai)界多重因素(su)影響(xiang)的(de)(de)(de)動態值。若(ruo)沒有(you)溫度(du)控制，最(zui)高充電(dian)(dian)(dian)電(dian)(dian)(dian)壓和切換電(dian)(dian)(dian)流(liu)都只(zhi)能(neng)設置成(cheng)定(ding)(ding)(ding)值，而(er)(er)這(zhe)(zhe)個定(ding)(ding)(ding)值無論(lun)如何(he)設置，都只(zhi)能(neng)在(zai)(zai)一個相對(dui)(dui)(dui)較小的(de)(de)(de)范圍內成(cheng)為(wei)最(zui)佳設置。為(wei)此，設計的(de)(de)(de)充電(dian)(dian)(dian)器通過(guo)對(dui)(dui)(dui)電(dian)(dian)(dian)壓、電(dian)(dian)(dian)流(liu)、溫度(du)等工作參數進(jin)行(xing)實時檢測(ce)，并按模糊理論(lun)的(de)(de)(de)評判規則(ze)對(dui)(dui)(dui)這(zhe)(zhe)些參數進(jin)行(xing)綜合分(fen)析，從而(er)(er)確定(ding)(ding)(ding)蓄電(dian)(dian)(dian)池(chi)是(shi)否充滿。

2. 3 軟件架構 
 

　　P IC16C712單(dan)片(pian)機的軟(ruan)件模塊(kuai)主要完(wan)成對傳(chuan)感器(qi)的輸入信號進(jin)行采(cai)集、對電源專用(yong)芯片(pian)UC3875進(jin)行控(kong)制、對異(yi)常進(jin)行處理等工(gong)作。在設(she)計過程(cheng)中，軟(ruan)件系統(tong)每隔10 s檢(jian)測一次(ci)電壓(ya)和電流； 每隔20 s檢(jian)測一次(ci)溫度。如(ru)有(you)異(yi)常，系統(tong)將通過LED提示用(yong)戶出現何種異(yi)常并采(cai)取相應(ying)的保護措(cuo)施(shi)。整(zheng)個系統(tong)的軟(ruan)件架構，如(ru)圖5所示。

圖5 軟件架構

　　　對充(chong)電器樣機(ji)進(jin)行的測試表明(ming)蓄電池充(chong)電器具有如下特性：

　　（1）輸入電壓： 220 Vac;

　　（2）輸出電壓： 40~60V;

　　（3）輸出(chu)電流： < 10A;

　　（4）功率(lv)因數(shu)： > 0. 99;

　　（5）充電噪(zao)聲(sheng)： < 20dB;

　　（6）充(chong)電(dian)時(shi)間： 6~8h;

　　（7）充電效率： > 85%;

　　（8）充電溫升： < 15℃；

　　（9）質(zhi)  量(liang)： < 0. 6kg.

　　此外，充電器還具有故障診斷功能。當充電回路電流或電壓過大、開路、短路時，充電器自動切(qie)斷主電路，同時點亮相應(ying)的LED故障(zhang)指(zhi)示燈指(zhi)示故障(zhang)原因(yin)，具(ju)有良好(hao)的保護特性。