目前市場上(shang)出售的(de)各種(zhong)(zhong)型號的(de)充電(dian)(dian)器要求外(wai)接(jie)電(dian)(dian)源時正、負極(ji)性(xing)(xing)絕對不能(neng)有誤(wu)，否(fou)則充電(dian)(dian)時將燒壞(huai)電(dian)(dian)池(chi)或電(dian)(dian)器，這里介紹一種(zhong)(zhong)安全(quan)型充電(dian)(dian)器電(dian)(dian)路(lu)，使用(yong)(yong)(yong)時可不用(yong)(yong)(yong)校正正負極(ji)性(xing)(xing)，直(zhi)接(jie)接(jie)入電(dian)(dian)池(chi)的(de)極(ji)性(xing)(xing)，即能(neng)安全(quan)充電(dian)(dian)，使用(yong)(yong)(yong)起(qi)來很得心順手。該無極(ji)性(xing)(xing)充電(dian)(dian)器電(dian)(dian)路(lu)見附圖所示。

　　該電(dian)路(lu)由二只雙向(xiang)可控硅“VT1、VT2’、兩(liang)只整流二極(ji)管(guan)“VD1、VD2’以及(ji)雙向(xiang)可控硅柵極(ji)觸(chu)發電(dian)路(lu)“R1、VD3、R2、VD4”等組成(cheng)。

　　若電(dian)(dian)(dian)路不(bu)連接(jie)蓄電(dian)(dian)(dian)池，兩只可控(kong)硅“VT1、VT2’均(jun)無柵(zha)電(dian)(dian)(dian)流(liu)，不(bu)導通，因此即使有交流(liu)輸入也沒(mei)有輸出電(dian)(dian)(dian)壓。確保安全。

　　當電(dian)(dian)路中輸出(chu)(+)端連(lian)接(jie)電(dian)(dian)池(chi)正(zheng)極(ji)、輸出(chu)(-)端接(jie)負極(ji)時，由(you)于蓄電(dian)(dian)池(chi)存在剩余電(dian)(dian)壓，將使(shi)VT1出(chu)柵(zha)極(ji)電(dian)(dian)流“經VT1、G極(ji)-VD3-R1”使(shi)VT1導通。在交流電(dian)(dian)正(zheng)半周(zhou)經VT1和VT2對(dui)蓄電(dian)(dian)池(chi)進(jin)行充電(dian)(dian)：相反，若蓄電(dian)(dian)池(chi)正(zheng)極(ji)連(lian)(-)端、負極(ji)連(lian)(+)端，則VT2有柵(zha)極(ji)電(dian)(dian)流而導通，通過(guo)VT2和VT1給蓄電(dian)(dian)池(chi)充電(dian)(dian)。

　　綜上所述：不(bu)(bu)(bu)論是電(dian)(dian)(dian)池正極、負極輸出(chu)，(+、-)、(-、+)端連接均能正常(chang)充電(dian)(dian)(dian)。如果(guo)蓄(xu)電(dian)(dian)(dian)池剩余電(dian)(dian)(dian)壓(ya)過小(xiao)不(bu)(bu)(bu)能觸發(fa)VT1或VT2導通，就(jiu)不(bu)(bu)(bu)能進行(xing)充電(dian)(dian)(dian)。對于(yu)這種情(qing)(qing)況，可用晶體管(guan)(guan)代替VD3和VD4來減小(xiao)晶閘管(guan)(guan)的(de)觸發(fa)電(dian)(dian)(dian)壓(ya)。而對于(yu)VT1、VT2和VD1、VD2器(qi)件的(de)要求(qiu)耐壓(ya)大于(yu)100V、連續工(gong)(gong)作電(dian)(dian)(dian)流(liu)(liu)為20A以上。VD3、VD4只需耐壓(ya)大于(yu)50V、工(gong)(gong)作電(dian)(dian)(dian)流(liu)(liu)100mA左右就(jiu)行(xing)了。具體情(qing)(qing)況根據蓄(xu)電(dian)(dian)(dian)池的(de)電(dian)(dian)(dian)壓(ya)及充電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)實際需要而確定，靈活掌握選用這些電(dian)(dian)(dian)子元器(qi)件。

　　例如：要(yao)(yao)對48V蓄電(dian)池充(chong)電(dian)，限流(liu)電(dian)阻R1、R2功率(lv)需要(yao)(yao)2W以上的電(dian)阻。但注意,T電(dian)源變壓器(qi)(qi)次級有直(zhi)流(liu)成(cheng)分電(dian)流(liu)通(tong)過，磁化電(dian)流(liu)增大，因此變壓器(qi)(qi)的設計容量要(yao)(yao)大些，次級輸(shu)出電(dian)壓分別為7V、14V、28V、42V、56V，S選用五擋(dang)轉換(huan)開關(guan)。其他元器(qi)(qi)件(jian)無(wu)特(te)殊要(yao)(yao)求(qiu)，按(an)圖中所(suo)標的參數為準。而輸(shu)出的正負(fu)極分別為：6V、12V、24V、36V、48V。