快速充(chong)電(dian)(dian)(dian)是指能在1～5h內使蓄電(dian)(dian)(dian)池達到或接(jie)近完(wan)全(quan)充(chong)電(dian)(dian)(dian)狀(zhuang)(zhuang)態(tai)的(de)(de)一種充(chong)電(dian)(dian)(dian)方法。常(chang)用于牽引用蓄電(dian)(dian)(dian)池需要在較短時(shi)間內恢復完(wan)全(quan)充(chong)電(dian)(dian)(dian)狀(zhuang)(zhuang)態(tai)時(shi)的(de)(de)充(chong)電(dian)(dian)(dian)。快速充(chong)電(dian)(dian)(dian)對蓄電(dian)(dian)(dian)池的(de)(de)性(xing)能和壽命有(you)損。蓄電(dian)(dian)(dian)池的(de)(de)正常(chang)充(chong)電(dian)(dian)(dian)耗時(shi)約10～20h，如何能快速充(chong)電(dian)(dian)(dian)而不損害蓄電(dian)(dian)(dian)池的(de)(de)性(xing)能和壽命，是人們(men)關注的(de)(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(jian)單、易于制作，幾乎不用維護及(ji)維修。

　　快速充電電路原理
　　AC220V市電(dian)(dian)(dian)(dian)經變壓(ya)(ya)(ya)(ya)器T1降(jiang)壓(ya)(ya)(ya)(ya)，經D1-D4全波整(zheng)流(liu)(liu)后，供給充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)路(lu)工作(zuo)。當輸(shu)出端按正確極性接入(ru)設定的(de)被充(chong)(chong)電(dian)(dian)(dian)(dian)瓶(ping)后，若(ruo)整(zheng)流(liu)(liu)輸(shu)出脈動電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)的(de)每個半波峰(feng)值(zhi)超過電(dian)(dian)(dian)(dian)瓶(ping)的(de)輸(shu)出電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，則(ze)可(ke)控硅(gui)(gui)SCR經Q的(de)集電(dian)(dian)(dian)(dian)極電(dian)(dian)(dian)(dian)流(liu)(liu)觸(chu)發(fa)導通，電(dian)(dian)(dian)(dian)流(liu)(liu)經可(ke)控硅(gui)(gui)給電(dian)(dian)(dian)(dian)瓶(ping)充(chong)(chong)電(dian)(dian)(dian)(dian)。脈動電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)接近電(dian)(dian)(dian)(dian)瓶(ping)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)時，可(ke)控硅(gui)(gui)關斷，停止(zhi)充(chong)(chong)電(dian)(dian)(dian)(dian)。調節(jie)R4，可(ke)調節(jie)晶體(ti)管Q的(de)導通電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，一般(ban)可(ke)將R4由大到小調整(zheng)到Q導通能觸(chu)發(fa)可(ke)控硅(gui)(gui)(導通)即可(ke)。圖中發(fa)光管D5用作(zuo)電(dian)(dian)(dian)(dian)源指(zhi)示，而D6用作(zuo)充(chong)(chong)電(dian)(dian)(dian)(dian)指(zhi)示。