隨著(zhu)油價的(de)(de)(de)(de)不(bu)斷上漲和(he)人們(men)環(huan)保(bao)意識的(de)(de)(de)(de)增強，電(dian)(dian)(dian)動自(zi)行車以其(qi)價格低、綠色環(huan)保(bao)，使(shi)(shi)用安全方便等優點越來越受到消費者(zhe)的(de)(de)(de)(de)喜愛。評價電(dian)(dian)(dian)動自(zi)行車質量好壞的(de)(de)(de)(de)重要參數之一是其(qi)蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)的(de)(de)(de)(de)使(shi)(shi)用壽命(ming)。而蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)的(de)(de)(de)(de)充(chong)(chong)電(dian)(dian)(dian)過程對其(qi)壽命(ming)影(ying)響(xiang)最大。研究表明：過充(chong)(chong)電(dian)(dian)(dian)，可使(shi)(shi)蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)發熱，電(dian)(dian)(dian)解液失(shi)水(shui)；而充(chong)(chong)電(dian)(dian)(dian)不(bu)足，則可使(shi)(shi)蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)內化學反應不(bu)充(chong)(chong)分，長期(qi)充(chong)(chong)電(dian)(dian)(dian)不(bu)足會導致蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)容(rong)量下(xia)降。由此可見，充(chong)(chong)電(dian)(dian)(dian)器(qi)性能(neng)的(de)(de)(de)(de)好壞直(zhi)接影(ying)響(xiang)著(zhu)蓄(xu)(xu)電(dian)(dian)(dian)池(chi)(chi)的(de)(de)(de)(de)使(shi)(shi)用效果(guo)和(he)使(shi)(shi)用壽命(ming)。

  目前市場上的充電器存在的主要不足，第一不是從副邊繞組直接獲得取樣信號，因而穩壓效果不理想；第二是輸出電流和電壓調節范圍窄，因而只適用于固定負載。為此，本文介紹了一種以單片機為控制器的通用智能充電器的(de)設(she)計方(fang)案。該(gai)裝置(zhi)能(neng)根據(ju)蓄電(dian)(dian)(dian)池的(de)充(chong)電(dian)(dian)(dian)特性(xing)或(huo)實(shi)時監測(ce)到的(de)充(chong)電(dian)(dian)(dian)狀態，來智能(neng)化地調節充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓和(he)充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流，而且調節范圍寬，并具(ju)有過流、過壓、過溫(wen)等保護功能(neng)。 1、系(xi)統結構 該(gai)系(xi)統主要(yao)由電(dian)(dian)(dian)源(yuan)變換電(dian)(dian)(dian)路、采樣電(dian)(dian)(dian)路、微處理器，脈寬調制器、鍵盤、顯示器和(he)溫(wen)度(du)傳感器等部分(fen)組(zu)成，是一(yi)個閉環的(de)智能(neng)充(chong)電(dian)(dian)(dian)系(xi)統。

   2、硬件電路 本智能充電器的(de)(de)(de)硬件電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)分為(wei)(wei)開(kai)關(guan)(guan)電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)部(bu)(bu)分、以單(dan)(dan)片機(ji)為(wei)(wei)主的(de)(de)(de)控(kong)制(zhi)(zhi)(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)和以UC3842為(wei)(wei)核心的(de)(de)(de)脈寬(kuan)調制(zhi)(zhi)(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)三部(bu)(bu)分。 2．1開(kai)關(guan)(guan)電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)設(she)計(ji) 本設(she)計(ji)采用電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)控(kong)制(zhi)(zhi)(zhi)型脈寬(kuan)調制(zhi)(zhi)(zhi)方式。其整個工作過程是將交流(liu)(liu)輸(shu)入經濾(lv)波(bo)、整流(liu)(liu)后(hou)變為(wei)(wei)直流(liu)(liu)高壓(ya)(ya)，再由開(kai)關(guan)(guan)管斬波(bo)、高頻變壓(ya)(ya)器(qi)降壓(ya)(ya)后(hou)得到高頻矩(ju)形電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，最后(hou)經過輸(shu)出(chu)(chu)整流(liu)(liu)濾(lv)波(bo)獲得所(suo)需(xu)要的(de)(de)(de)直流(liu)(liu)輸(shu)出(chu)(chu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。系(xi)統對開(kai)關(guan)(guan)電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)的(de)(de)(de)要求(qiu)是其交流(liu)(liu)輸(shu)入電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)范圍為(wei)(wei)90～270 V，能同(tong)時輸(shu)出(chu)(chu)+5V作為(wei)(wei)控(kong)制(zhi)(zhi)(zhi)部(bu)(bu)分電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)及12～60 V主回路(lu)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。輸(shu)出(chu)(chu)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)為(wei)(wei)1～3 A。 2．2單(dan)(dan)片機(ji)控(kong)制(zhi)(zhi)(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)設(she)計(ji) 單(dan)(dan)片機(ji)控(kong)制(zhi)(zhi)(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)主要由單(dan)(dan)片機(ji)AT89S52、ADCTLC0832、多(duo)路(lu)選擇開(kai)關(guan)(guan)CD4051、數字(zi)電(dian)(dian)(dian)(dian)(dian)(dian)位器(qi)X9C102、數字(zi)溫度傳感器(qi)DSl8820、取樣電(dian)(dian)(dian)(dian)(dian)(dian)阻Rs和Rw、2×4鍵盤(pan)、液(ye)晶顯示CONl6等組成。

    本(ben)部分設(she)(she)計時應先(xian)根據蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)型號(hao)參數，來通過(guo)(guo)鍵盤設(she)(she)計與之對應的(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)、充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)以及充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)時間(jian)，當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路接上(shang)(shang)蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)后，充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)過(guo)(guo)程開始(shi)，此(ci)后由(you)單(dan)片(pian)(pian)(pian)(pian)(pian)機(ji)(ji)通過(guo)(guo)取樣電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)RM檢(jian)(jian)(jian)測(ce)(ce)(ce)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，若檢(jian)(jian)(jian)測(ce)(ce)(ce)到蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)因過(guo)(guo)渡放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)而(er)使(shi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)低于正常范圍(wei)。那么，為了(le)避免充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)過(guo)(guo)大(da)(da)而(er)造成(cheng)蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)損壞，應先(xian)對蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)實行(xing)穩定(ding)(ding)的(de)(de)小電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)本(ben)設(she)(she)計程序中設(she)(she)為l／5的(de)(de)設(she)(she)定(ding)(ding)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)，同時，單(dan)片(pian)(pian)(pian)(pian)(pian)機(ji)(ji)開始(shi)計時，之后單(dan)片(pian)(pian)(pian)(pian)(pian)機(ji)(ji)將(jiang)不斷檢(jian)(jian)(jian)測(ce)(ce)(ce)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)和(he)(he)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)并顯(xian)示在液晶屏上(shang)(shang)，隨著充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)進行(xing)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)不斷上(shang)(shang)升(sheng)(sheng)，當(dang)上(shang)(shang)升(sheng)(sheng)到正常范圍(wei)時，單(dan)片(pian)(pian)(pian)(pian)(pian)機(ji)(ji)可通過(guo)(guo)控制數字(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)位器來調節輸出電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，從(cong)(cong)而(er)轉(zhuan)(zhuan)入大(da)(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)恒流(liu)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)即設(she)(she)定(ding)(ding)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)方式，此(ci)后，單(dan)片(pian)(pian)(pian)(pian)(pian)機(ji)(ji)一直保(bao)持不停地檢(jian)(jian)(jian)測(ce)(ce)(ce)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)達到設(she)(she)定(ding)(ding)值(zhi)(zhi)(zhi)時，單(dan)片(pian)(pian)(pian)(pian)(pian)機(ji)(ji)發出指令，以增大(da)(da)數字(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)位器的(de)(de)阻(zu)值(zhi)(zhi)(zhi)，并通過(guo)(guo)脈寬調制減(jian)小輸出電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。從(cong)(cong)而(er)使(shi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)減(jian)小，當(dang)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)減(jian)小到1／5的(de)(de)設(she)(she)定(ding)(ding)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)時，再轉(zhuan)(zhuan)為涓流(liu)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，最后在充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)時間(jian)到時關閉電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源，這(zhe)樣就避免了(le)因電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)溫升(sheng)(sheng)過(guo)(guo)快或(huo)嚴(yan)重極(ji)化而(er)影響充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)質量，提高(gao)(gao)蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)使(shi)用壽命。當(dang)檢(jian)(jian)(jian)測(ce)(ce)(ce)到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)、充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)和(he)(he)溫度超過(guo)(guo)設(she)(she)定(ding)(ding)值(zhi)(zhi)(zhi)的(de)(de)1／10倍時由(you)程序設(she)(she)定(ding)(ding)，單(dan)片(pian)(pian)(pian)(pian)(pian)機(ji)(ji)立(li)即輸出報警(jing)(jing)信號(hao)報警(jing)(jing)。同時使(shi)繼電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)器動作并切斷總電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源，以提高(gao)(gao)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)安全性和(he)(he)可靠性。

   顯示器可用(yong)于顯示單(dan)片(pian)機(ji)(ji)(ji)實時(shi)采樣(yang)到的蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)、充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)、已充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi)間和蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池的溫度(du)，鍵盤則用(yong)于設定充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極限電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)、恒流(liu)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)極限充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)和充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi)間。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路中的單(dan)片(pian)機(ji)(ji)(ji)可通過串口(kou)RS232和上位機(ji)(ji)(ji)相連，以用(yong)于存儲(chu)數(shu)(shu)據和虛擬顯示充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)參(can)數(shu)(shu)的設定。當檢(jian)測到充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)為零(ling)時(shi)，單(dan)片(pian)機(ji)(ji)(ji)轉入休眠狀態。而(er)當檢(jian)測到充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)不為零(ling)時(shi)，單(dan)片(pian)機(ji)(ji)(ji)被(bei)激活(huo)。

   2．3 PWM控制器設計 PW M控制器部分是以UC3842為核心。UC3842芯片內含有5.0 V基準電壓穩壓器、高增益誤差放大器和脈沖寬度比較器，它可以控制芯片內的驅動器。而驅動器則可提供25 mA的輸出電流．可直接驅動NOSFET調整管，從而調整充電器的(de)輸出電壓和(he)電流。由于該驅動(dong)器同時具有過流、過壓保護(hu)，工(gong)作電源電壓可以在8～40 V，而啟(qi)(qi)動(dong)電流小于1 mA，工(gong)作溫度為O～70℃，因而是目(mu)前較理想的(de)新(xin)型脈寬調制器。 PWM控制器在啟(qi)(qi)動(dong)時，是由R1、Rw。

   為(wei)(wei)UC3842提供(gong)啟動電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)，待其工(gong)作后(hou)，其輔助繞(rao)組3、4端的(de)(de)(de)(de)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)經(jing)D1整流(liu)、C4、C5濾(lv)波(bo)、DW1穩(wen)壓(ya)(ya)(ya)(ya)(ya)(ya)后(hou)得到的(de)(de)(de)(de)16 V直(zhi)流(liu)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)，一(yi)路加(jia)到UC38427的(de)(de)(de)(de)7腳為(wei)(wei)其供(gong)電(dian)(dian)(dian)，另(ling)一(yi)路經(jing)R3和數字電(dian)(dian)(dian)位(wei)器X9C102分壓(ya)(ya)(ya)(ya)(ya)(ya)后(hou)加(jia)到UC3842的(de)(de)(de)(de)2腳。以作為(wei)(wei)脈寬(kuan)調(diao)制(zhi)的(de)(de)(de)(de)輸(shu)入信號。一(yi)般在(zai)這(zhe)(zhe)類電(dian)(dian)(dian)源的(de)(de)(de)(de)設(she)計中，輸(shu)出電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)取(qu)(qu)樣可與UC3842的(de)(de)(de)(de)供(gong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)相(xiang)連。為(wei)(wei)了反(fan)映(ying)輸(shu)出電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)變化(hua)，本設(she)計沒(mei)有(you)加(jia)穩(wen)壓(ya)(ya)(ya)(ya)(ya)(ya)管，但(dan)這(zhe)(zhe)會使UC3842的(de)(de)(de)(de)工(gong)作電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)不穩(wen)，輸(shu)出諧波(bo)成分增多，為(wei)(wei)了克服此不足，本設(she)計中UC3842的(de)(de)(de)(de)供(gong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)采用(yong)由(you)3、4繞(rao)組端壓(ya)(ya)(ya)(ya)(ya)(ya)單(dan)(dan)獨整流(liu)、濾(lv)波(bo)、穩(wen)壓(ya)(ya)(ya)(ya)(ya)(ya)后(hou)，提供(gong)給UC3842芯片(pian)16 V的(de)(de)(de)(de)穩(wen)定電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)。充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)的(de)(de)(de)(de)調(diao)節(jie)是將(jiang)電(dian)(dian)(dian)池電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)經(jing)外環電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)取(qu)(qu)樣電(dian)(dian)(dian)路R12、RM取(qu)(qu)樣，再經(jing)多路電(dian)(dian)(dian)子開關選擇、MD變換(huan)，單(dan)(dan)片(pian)機處理(li)后(hou)，送入數字電(dian)(dian)(dian)位(wei)器，以控制(zhi)數字電(dian)(dian)(dian)位(wei)器的(de)(de)(de)(de)有(you)效(xiao)電(dian)(dian)(dian)阻。

   從而間接控制UC3842的2腳電壓，進而控制脈沖占空比，以改變充電電壓。 充電器輸出電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)偏高(gao)時(shi)，反饋(kui)回UC3842的(de)(de)2腳電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)也(ye)升(sheng)高(gao)超過(guo)參考(kao)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)2.5 V之后(hou)，驅動信號的(de)(de)脈沖占空比減(jian)小(xiao)，使(shi)輸出電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)下降，從而(er)達(da)到穩壓(ya)的(de)(de)目的(de)(de)。充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流的(de)(de)調(diao)節(jie)(jie)主要是(shi)先將充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流經外環電(dian)(dian)(dian)(dian)(dian)(dian)流取樣(yang)電(dian)(dian)(dian)(dian)(dian)(dian)阻Rs取樣(yang)和LM358放大可用(yong)R1調(diao)節(jie)(jie)放大倍數、多路電(dian)(dian)(dian)(dian)(dian)(dian)子開(kai)關選擇、MD變換(huan)，再送單(dan)片機(ji)處(chu)理，然后(hou)調(diao)節(jie)(jie)數字電(dian)(dian)(dian)(dian)(dian)(dian)位器的(de)(de)阻值(zhi)。其調(diao)節(jie)(jie)過(guo)程(cheng)與電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)調(diao)節(jie)(jie)相似，實際上(shang)，電(dian)(dian)(dian)(dian)(dian)(dian)流調(diao)節(jie)(jie)也(ye)是(shi)通過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)調(diao)節(jie)(jie)實現的(de)(de)。

    2．4．保(bao)護(hu)電(dian)(dian)(dian)(dian)路設計 當過(guo)(guo)流(liu)(liu)或短路時(shi)(shi)，內(nei)(nei)環(huan)取樣電(dian)(dian)(dian)(dian)阻(zu)R10兩端(duan)的(de)電(dian)(dian)(dian)(dian)壓(ya)升(sheng)高(gao)。當3腳電(dian)(dian)(dian)(dian)壓(ya)超過(guo)(guo)1伏時(shi)(shi)，通(tong)過(guo)(guo)UC3842的(de)內(nei)(nei)部調(diao)制可(ke)(ke)使其停(ting)止脈寬輸(shu)出(chu)，開(kai)關(guan)管截止，輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓(ya)和電(dian)(dian)(dian)(dian)流(liu)(liu)均為0，從(cong)而(er)(er)保(bao)護(hu)電(dian)(dian)(dian)(dian)源(yuan)。過(guo)(guo)壓(ya)時(shi)(shi)，DW1和DW2會(hui)(hui)擊穿而(er)(er)短路，也會(hui)(hui)造成過(guo)(guo)流(liu)(liu)保(bao)護(hu)，DW2可(ke)(ke)用以(yi)(yi)保(bao)護(hu)場效(xiao)應管和UC3842。而(er)(er)當發(fa)生(sheng)欠壓(ya)時(shi)(shi)，即當UC3842的(de)7腳電(dian)(dian)(dian)(dian)壓(ya)降至10 V以(yi)(yi)下時(shi)(shi)，UC3842將啟動欠壓(ya)鎖定電(dian)(dian)(dian)(dian)路而(er)(er)關(guan)閉開(kai)關(guan)控制器。內(nei)(nei)環(huan)的(de)這種反饋(kui)調(diao)整是(shi)(shi)在輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓(ya)尚未發(fa)生(sheng)變(bian)化時(shi)(shi)，通(tong)過(guo)(guo)檢測內(nei)(nei)環(huan)電(dian)(dian)(dian)(dian)流(liu)(liu)使脈寬提前得到(dao)調(diao)整，前饋(kui)控制，從(cong)而(er)(er)加快了變(bian)換(huan)器對異常(chang)(chang)情況的(de)動態響(xiang)應速度。以(yi)(yi)便更(geng)加快速有效(xiao)地起到(dao)保(bao)護(hu)作用。當然，外環(huan)電(dian)(dian)(dian)(dian)流(liu)(liu)、電(dian)(dian)(dian)(dian)壓(ya)的(de)取樣Rs、Rw亦(yi)可(ke)(ke)通(tong)過(guo)(guo)單片機的(de)調(diao)節作用來達到(dao)對異常(chang)(chang)情況的(de)保(bao)護(hu)，但響(xiang)應速度比內(nei)(nei)環(huan)慢5～10個工頻周(zhou)期，因此，外環(huan)取樣主要是(shi)(shi)調(diao)節充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)(liu)和充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓(ya)，兼(jian)作二次(ci)保(bao)護(hu)，而(er)(er)內(nei)(nei)環(huan)取樣則是(shi)(shi)主要的(de)，它(ta)是(shi)(shi)一次(ci)的(de)保(bao)護(hu)，這種雙環(huan)保(bao)護(hu)方式會(hui)(hui)更(geng)加安全可(ke)(ke)靠。

    3、軟件設(she)(she)計(ji) 在(zai)程序(xu)的(de)(de)初(chu)(chu)始階段，首先是(shi)(shi)對單片(pian)機進(jin)(jin)行初(chu)(chu)始化，即根(gen)據不(bu)同(tong)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)設(she)(she)定(ding)不(bu)同(tong)的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)參數，選擇不(bu)同(tong)的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)策略。其后是(shi)(shi)判(pan)斷(duan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)是(shi)(shi)否(fou)連接正確，根(gen)據電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)值判(pan)斷(duan)應該進(jin)(jin)入(ru)哪一(yi)個充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)階段即小電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)預(yu)(yu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，大(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)恒(heng)(heng)流(liu)(liu)(liu)(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)或恒(heng)(heng)壓(ya)(ya)(ya)涓流(liu)(liu)(liu)(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)。在(zai)預(yu)(yu)充(chong)階段，應降低充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，而在(zai)恒(heng)(heng)流(liu)(liu)(liu)(liu)方式(shi)時，應不(bu)斷(duan)檢測充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)是(shi)(shi)否(fou)達(da)到恒(heng)(heng)定(ding)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)如1.8 A，如果(guo)小于(yu)1.8 A，則抬高電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)兩端(duan)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，使之達(da)到1.8 A，以上調節過(guo)程均可(ke)采用(yong)比例(li)控(kong)制。在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)兩端(duan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)達(da)到設(she)(she)定(ding)值后，系統再(zai)進(jin)(jin)入(ru)涓流(liu)(liu)(liu)(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)模式(shi)。該充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)器的(de)(de)程序(xu)流(liu)(liu)(liu)(liu)程如圖(tu)3所示。圖(tu)3中，Is為設(she)(she)定(ding)的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)即恒(heng)(heng)流(liu)(liu)(liu)(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)，Umin為蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)極限電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，Umax為蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)極限電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)。

   應用試驗 本設計選用了電動自行車常用的36 V／12 Ah鉛酸蓄電池作為測試對象，其恒壓充電電壓設定為43 V，恒流充電電流Is為1.8 A，起始時，隨著充電的進行，充電電流幾乎維持1.8 A不變，但電池電壓不斷升高，當充電3小時后。電壓上升減慢；當充電到4小時后，充電電壓接近43 V；之后電壓上升更加緩慢。而且充電下降較快。當充到43 V時，充電器自動停止。從(cong)測(ce)試數據來看，該設(she)(she)(she)計(ji)達到了恒流(liu)快充(chong)(chong)(chong)，恒壓(ya)涓充(chong)(chong)(chong)，充(chong)(chong)(chong)滿自行(xing)關斷(duan)的(de)設(she)(she)(she)計(ji)要(yao)求(qiu)。 5、結束語(yu) 本文設(she)(she)(she)計(ji)的(de)過(guo)度放電(dian)(dian)(dian)(dian)(dian)(dian)預充(chong)(chong)(chong)、恒流(liu)快充(chong)(chong)(chong)、恒壓(ya)涓充(chong)(chong)(chong)、智(zhi)能控(kong)制(zhi)的(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方(fang)案，能很(hen)好地(di)解(jie)決電(dian)(dian)(dian)(dian)(dian)(dian)動自行(xing)車用電(dian)(dian)(dian)(dian)(dian)(dian)池在充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過(guo)程(cheng)中存(cun)在的(de)過(guo)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)、充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)不足和發熱等問題，并能根據不同(tong)電(dian)(dian)(dian)(dian)(dian)(dian)池選擇不同(tong)的(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方(fang)案。而且具有(you)通用性。能實(shi)時檢測(ce)并顯示充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)、充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)、充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)時間和蓄電(dian)(dian)(dian)(dian)(dian)(dian)池溫度等參(can)數。由于電(dian)(dian)(dian)(dian)(dian)(dian)路具有(you)內外環控(kong)制(zhi)，符合最(zui)優(you)控(kong)制(zhi)規律(lv)。最(zui)具有(you)過(guo)流(liu)、過(guo)壓(ya)和超溫保護功能，同(tong)時由于

   UC3842采用(yong)穩壓(ya)供電(dian)，因此，不(bu)但(dan)諧波(bo)污染(ran)程度低，原副(fu)邊電(dian)氣隔離安(an)全可(ke)靠，同時還(huan)可(ke)根據負載(zai)情(qing)況通過(guo)單片(pian)機(ji)來進行控制，并可(ke)實現跳周期模(mo)式工作。故可(ke)提高(gao)電(dian)源(yuan)的(de)效率。