快(kuai)速(su)充(chong)(chong)電(dian)(dian)是(shi)指(zhi)能(neng)在(zai)1～5h內使蓄(xu)電(dian)(dian)池(chi)(chi)達到(dao)或(huo)接近(jin)完(wan)全充(chong)(chong)電(dian)(dian)狀態(tai)的(de)一種(zhong)充(chong)(chong)電(dian)(dian)方法。常用(yong)于牽(qian)引(yin)用(yong)蓄(xu)電(dian)(dian)池(chi)(chi)需(xu)要在(zai)較(jiao)短時(shi)間(jian)內恢(hui)復完(wan)全充(chong)(chong)電(dian)(dian)狀態(tai)時(shi)的(de)充(chong)(chong)電(dian)(dian)。快(kuai)速(su)充(chong)(chong)電(dian)(dian)對蓄(xu)電(dian)(dian)池(chi)(chi)的(de)性能(neng)和壽(shou)命(ming)有損。蓄(xu)電(dian)(dian)池(chi)(chi)的(de)正常充(chong)(chong)電(dian)(dian)耗時(shi)約(yue)10～20h，如何能(neng)快(kuai)速(su)充(chong)(chong)電(dian)(dian)而不(bu)損害蓄(xu)電(dian)(dian)池(chi)(chi)的(de)性能(neng)和壽(shou)命(ming)，是(shi)人(ren)們(men)關注的(de)熱門研究課題。

快速充電電路特點
　　1、輸出電壓設定好后(例如36V)，若被充電瓶極板脫落斷開，造成某組電池不通，或出現短路，則電瓶端電壓即降低或為零，這時充電器將無輸出電流。
　　2、若被充電瓶電壓偏離設定電壓，如設定電壓為36V，誤接24V、12V、6V電瓶等，充電器也無輸出電流，若設定為24V誤接為36V電瓶，由于充電器輸出電壓低于電瓶電壓，因而也不能向電瓶充電。 　　
　　3、充電器兩輸出端若短路時，由于充電器中可控硅SCR的觸發電路不能工作，因而可控硅不導通，輸出電流為零。 　　
　　4、若使用時誤將電瓶正負極接反，則可控硅觸發電路反向截止，無觸發信號，可控硅不導通，輸出電流為零。 　　
　　5、采用脈沖充電，有利于延長電瓶壽命。由于低壓交流電經全波整流后是脈動直流，只有當其波峰電壓大于電瓶電壓時，可控硅才會導通，而當脈動直流電壓處于波谷區時，可控硅反偏截止，停止向電瓶充電，因而流過電瓶的是脈動直流電。 　　
　　6、快速充電，充滿自停。由于剛開始充電時電瓶兩端電壓較低，因而充電電流較大。當電瓶即將充足時(36V電瓶端電壓可達44V)，由于充電電壓越來越接近脈動直流輸出電壓的波峰值，則充電電流也會越來越小，自動變為涓流充電。當電瓶兩端電壓被充到整流輸出的波峰最大值時，充電過程停止。經試驗，三節電動車蓄電池36V(12V／12Ah三節串聯)，用該充電器只需幾個小時即可充滿。 　　
　　7、電路簡單(dan)、易(yi)于制作，幾乎不用維護及維修(xiu)。

　　快速充電電路原理
　　AC220V市(shi)電(dian)(dian)(dian)(dian)經(jing)變壓(ya)(ya)(ya)器(qi)T1降壓(ya)(ya)(ya)，經(jing)D1-D4全波(bo)整(zheng)流(liu)后，供給充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)路(lu)工作。當輸(shu)出(chu)端按正(zheng)確極性(xing)接入設定(ding)的被充(chong)電(dian)(dian)(dian)(dian)瓶(ping)后，若整(zheng)流(liu)輸(shu)出(chu)脈動(dong)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)的每(mei)個半波(bo)峰值超過電(dian)(dian)(dian)(dian)瓶(ping)的輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，則可(ke)控(kong)硅SCR經(jing)Q的集電(dian)(dian)(dian)(dian)極電(dian)(dian)(dian)(dian)流(liu)觸發(fa)導(dao)通，電(dian)(dian)(dian)(dian)流(liu)經(jing)可(ke)控(kong)硅給電(dian)(dian)(dian)(dian)瓶(ping)充(chong)電(dian)(dian)(dian)(dian)。脈動(dong)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)接近電(dian)(dian)(dian)(dian)瓶(ping)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)時，可(ke)控(kong)硅關斷，停止充(chong)電(dian)(dian)(dian)(dian)。調節R4，可(ke)調節晶體管(guan)(guan)Q的導(dao)通電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，一(yi)般可(ke)將R4由大到小(xiao)調整(zheng)到Q導(dao)通能觸發(fa)可(ke)控(kong)硅(導(dao)通)即(ji)可(ke)。圖中發(fa)光管(guan)(guan)D5用(yong)作電(dian)(dian)(dian)(dian)源指示(shi)，而D6用(yong)作充(chong)電(dian)(dian)(dian)(dian)指示(shi)。