各種移動設備的飛速發展，也加快了充電電池的發展，為了滿足現今移動設備的需要，充電電池的容量也越來越大，其中鎳氫充電電池是大容量電池的主要品種，在電力電子、交通以及通信領域有了較多的應用，在很多智能儀器儀表中，鎳氫電池常用來作為備用電池，充電器是充電電池的必備品，這篇文章就來講述一種基于分立元件構成的電池自動恒流充電電路(lu)(lu)，著重講述(shu)了充(chong)電電路(lu)(lu)的(de)組成、結構特點、工(gong)作原理(li)及電路(lu)(lu)的(de)調節(jie)。

1 電路總體(ti)設計思路

簡易電(dian)(dian)(dian)池(chi)自動(dong)恒流充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)路(lu)的總體框圖如圖1所示(shi)(shi)。它是由(you)變壓器整流電(dian)(dian)(dian)路(lu)、恒流產生(sheng)電(dian)(dian)(dian)路(lu)、自動(dong)斷(duan)電(dian)(dian)(dian)電(dian)(dian)(dian)路(lu)、顯示(shi)(shi)電(dian)(dian)(dian)路(lu)和電(dian)(dian)(dian)源電(dian)(dian)(dian)路(lu)5部分構成。

變壓(ya)(ya)器整(zheng)流(liu)電(dian)(dian)(dian)(dian)路(lu)的(de)功(gong)(gong)能(neng)是(shi)將(jiang)(jiang)公共電(dian)(dian)(dian)(dian)網中(zhong)的(de)220V交流(liu)電(dian)(dian)(dian)(dian)轉換(huan)為(wei)合(he)適的(de)電(dian)(dian)(dian)(dian)流(liu)和電(dian)(dian)(dian)(dian)壓(ya)(ya)信號，從(cong)而為(wei)后續電(dian)(dian)(dian)(dian)路(lu)提供(gong)信號。恒流(liu)產(chan)生電(dian)(dian)(dian)(dian)路(lu)的(de)功(gong)(gong)能(neng)是(shi)利(li)用晶體管(guan)電(dian)(dian)(dian)(dian)流(liu)源(yuan)為(wei)電(dian)(dian)(dian)(dian)路(lu)產(chan)生恒定(ding)的(de)充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)。自動(dong)斷(duan)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)路(lu)的(de)功(gong)(gong)能(neng)是(shi)利(li)用三極管(guan)飽和導通時的(de)電(dian)(dian)(dian)(dian)壓(ya)(ya)特(te)性，從(cong)而實現電(dian)(dian)(dian)(dian)路(lu)當(dang)電(dian)(dian)(dian)(dian)池充(chong)滿(man)電(dian)(dian)(dian)(dian)時能(neng)夠自動(dong)切斷(duan)電(dian)(dian)(dian)(dian)源(yuan)。顯示電(dian)(dian)(dian)(dian)路(lu)的(de)功(gong)(gong)能(neng)是(shi)利(li)用發光(guang)二極管(guan)將(jiang)(jiang)電(dian)(dian)(dian)(dian)路(lu)開(kai)始(shi)充(chong)電(dian)(dian)(dian)(dian)和結(jie)束充(chong)電(dian)(dian)(dian)(dian)的(de)狀(zhuang)態(tai)顯示出來。穩壓(ya)(ya)電(dian)(dian)(dian)(dian)源(yuan)電(dian)(dian)(dian)(dian)路(lu)的(de)功(gong)(gong)能(neng)是(shi)為(wei)上述所有電(dian)(dian)(dian)(dian)路(lu)提供(gong)直流(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)。

1.1 變壓(ya)器整流(liu)電路(lu)及電源電路(lu)的設計

變(bian)(bian)壓(ya)(ya)(ya)器(qi)(qi)整流(liu)電(dian)(dian)路(lu)(lu)和(he)穩壓(ya)(ya)(ya)電(dian)(dian)源(yuan)電(dian)(dian)路(lu)(lu)(如圖2虛線左邊(bian)所示(shi))，其(qi)(qi)主要由變(bian)(bian)壓(ya)(ya)(ya)器(qi)(qi)、二(er)極管(guan)(guan)橋(qiao)式(shi)電(dian)(dian)路(lu)(lu)、電(dian)(dian)容構成(cheng)。其(qi)(qi)中(zhong)變(bian)(bian)壓(ya)(ya)(ya)器(qi)(qi)采用常規(gui)的(de)鐵心變(bian)(bian)壓(ya)(ya)(ya)器(qi)(qi)，并將公共(gong)電(dian)(dian)網中(zhong)的(de)220 V交(jiao)流(liu)電(dian)(dian)變(bian)(bian)為12 V交(jiao)流(liu)電(dian)(dian)，再通過二(er)極管(guan)(guan)橋(qiao)式(shi)電(dian)(dian)路(lu)(lu)進行(xing)整流(liu)和(he)電(dian)(dian)容C1濾波。整流(liu)信(xin)號(hao)由VC1引出(chu)。在此基礎上再接(jie)三端(duan)穩壓(ya)(ya)(ya)器(qi)(qi)CW7812及電(dian)(dian)容C3、C4(如圖2虛線右邊(bian)所示(shi))，這樣整個電(dian)(dian)路(lu)(lu)就構成(cheng)穩壓(ya)(ya)(ya)電(dian)(dian)源(yuan)電(dian)(dian)路(lu)(lu)。由B點(dian)提供+12 V的(de)直流(liu)電(dian)(dian)壓(ya)(ya)(ya)。

1.2 恒流電(dian)路的(de)設(she)計

如圖3所示，由穩壓管(guan)VZ1、晶體管(guan)VT1、電(dian)(dian)阻(zu)R1、電(dian)(dian)容C2構成的晶體管(guan)電(dian)(dian)流源提供恒定電(dian)(dian)流，

取穩壓(ya)管電(dian)壓(ya)為(wei)5 V，R1為(wei)51 Ω，此時IC≈1OO mA，作為(wei)電(dian)路的充電(dian)電(dian)流。

1.3 自動充(chong)電(dian)(dian)檢測電(dian)(dian)路和指示電(dian)(dian)路的設計(ji)

如圖4電(dian)(dian)(dian)路(lu)所示，自動(dong)斷(duan)電(dian)(dian)(dian)電(dian)(dian)(dian)路(lu)是由(you)三極管(guan)VT2、電(dian)(dian)(dian)壓跟隨器(qi)A1、電(dian)(dian)(dian)壓比(bi)較(jiao)器(qi)A2電(dian)(dian)(dian)阻R4、R5、R6、R7、R8、R11和可變電(dian)(dian)(dian)阻RP1構成(cheng)。當充(chong)電(dian)(dian)(dian)開始時(shi)(shi)，電(dian)(dian)(dian)壓比(bi)較(jiao)器(qi)輸出高電(dian)(dian)(dian)平，VT2導通，VT1也導通，指示燈發(fa)光(guang)二極管(guan)亮(liang)，給電(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)。可以先設(she)定轉(zhuan)換(huan)開關為1時(shi)(shi)給一(yi)節(jie)電(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)，轉(zhuan)換(huan)開關為2時(shi)(shi)給二節(jie)電(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)，依次類(lei)推，實現對1-4節(jie)電(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)。當電(dian)(dian)(dian)充(chong)滿時(shi)(shi)，電(dian)(dian)(dian)壓比(bi)較(jiao)器(qi)輸出低電(dian)(dian)(dian)平，VT2截止(zhi)，VT1不導通，發(fa)光(guang)二極管(guan)熄滅(mie)，充(chong)電(dian)(dian)(dian)完(wan)畢。

 2 簡易(yi)充電器總電路原理圖及(ji)元器件清單

2.1 簡易(yi)充電器總電路原理圖

簡易電池自動恒流充(chong)電電路的(de)總(zong)電路圖如圖5所示。它(ta)是由變壓(ya)器整(zheng)流電路、恒流產生電路、充(chong)電檢測電路、顯示電路和電源電路5部分構(gou)成。總(zong)電路圖中需要(yao)注意的(de)是各個單元電路之間的(de)連接一定(ding)要(yao)準確，同時各部分的(de)布局要(yao)合理(li)。

2.2 元(yuan)器件清單

本設計用的(de)元件清單如表1。

3 結束語

通過(guo)以上的講解我(wo)們(men)發(fa)現簡易電(dian)(dian)池自動恒(heng)流充電(dian)(dian)電(dian)(dian)路具(ju)有很多優點，電(dian)(dian)路結構(gou)簡單、功能完善、調(diao)節方便等，適合無線電(dian)(dian)愛好者自行制作及高(gao)職學生電(dian)(dian)子實(shi)訓。

                                                                                                         本文摘自(zi)于中國充電器網