静电(dian)(dian)除尘(chen)(chen)器的(de)(de)工作原理由于辐射摩擦等原因，空气中含有少量的(de)(de)自(zi)由离(li)子(zi)(zi)，单靠这些自(zi)由离(li)子(zi)(zi)是不可能(neng)使含尘(chen)(chen)空气中的(de)(de)尘(chen)(chen)粒充分荷(he)电(dian)(dian)的(de)(de)。因此(ci)，要利用(yong)静电(dian)(dian)使粉(fen)尘(chen)(chen)分离(li)须具备两(liang)个基(ji)本(ben)条(tiao)件:一是存(cun)在使粉(fen)尘(chen)(chen)荷(he)电(dian)(dian)的(de)(de)电(dian)(dian)场;二是存(cun)在使荷(he)电(dian)(dian)粉(fen)尘(chen)(chen)颗粒分离(li)的(de)(de)电(dian)(dian)场。

一(yi)般(ban)的(de)(de)静电(dian)(dian)除尘器采(cai)用(yong)(yong)(yong)荷电(dian)(dian)电(dian)(dian)场和(he)分离(li)电(dian)(dian)场合一(yi)的(de)(de)方法，高(gao)压电(dian)(dian)场，放(fang)电(dian)(dian)极(ji)(ji)(ji)接高(gao)压直流(liu)电(dian)(dian)源的(de)(de)负极(ji)(ji)(ji)，集(ji)尘极(ji)(ji)(ji)接地为正极(ji)(ji)(ji)，集(ji)尘极(ji)(ji)(ji)可(ke)以采(cai)用(yong)(yong)(yong)平板(ban):也可(ke)以采(cai)用(yong)(yong)(yong)圆管在电(dian)(dian)场作用(yong)(yong)(yong)下，空气中的(de)(de)自由离(li)子(zi)要向两极(ji)(ji)(ji)移动(dong)，电(dian)(dian)压愈(yu)高(gao)、电(dian)(dian)场强度(du)愈(yu)高(gao)，离(li)子(zi)的(de)(de)运(yun)动(dong)速度(du)愈(yu)快。

由于(yu)离(li)(li)子(zi)(zi)(zi)的运(yun)动,极(ji)间形(xing)成了电(dian)流。开始时,空(kong)(kong)气中(zhong)的自(zi)由离(li)(li)子(zi)(zi)(zi)少，电(dian)流较(jiao)小。电(dian)压升高到一(yi)(yi)定(ding)值(zhi)后(hou)(hou)，放电(dian)极(ji)附近(jin)的离(li)(li)子(zi)(zi)(zi)获得了较(jiao)高的能量和速度，它们撞击空(kong)(kong)气中(zhong)的中(zhong)性(xing)原(yuan)子(zi)(zi)(zi)时，中(zhong)性(xing)原(yuan)子(zi)(zi)(zi)会分解成正、负(fu)离(li)(li)子(zi)(zi)(zi),这种现象称(cheng)为空(kong)(kong)气电(dian)离(li)(li)。空(kong)(kong)气电(dian)离(li)(li)后(hou)(hou)，由于(yu)连锁(suo)反应(ying)，在极(ji)间运(yun)动的离(li)(li)子(zi)(zi)(zi)数大大增加，表现为极(ji)间的电(dian)流(称(cheng)之为电(dian)晕(yun)电(dian)流)急剧(ju)增加，空(kong)(kong)气成了导体。放电(dian)极(ji)周围的空(kong)(kong)气全部电(dian)离(li)(li)后(hou)(hou)，在放电(dian)极(ji)周围可以(yi)看见一(yi)(yi)圈(quan)淡蓝色的光环，这个光环称(cheng)为电(dian)晕(yun)。因此，这个放电(dian)的导线被称(cheng)为电(dian)晕(yun)极(ji)。

在(zai)离电(dian)(dian)(dian)(dian)(dian)晕(yun)极较远的(de)(de)地方，电(dian)(dian)(dian)(dian)(dian)场强度小，离子的(de)(de)运动速度也(ye)较小，那里的(de)(de)空(kong)气(qi)(qi)还没有被电(dian)(dian)(dian)(dian)(dian)离。如果进(jin)一(yi)(yi)步(bu)提高电(dian)(dian)(dian)(dian)(dian)压，空(kong)气(qi)(qi)电(dian)(dian)(dian)(dian)(dian)离(电(dian)(dian)(dian)(dian)(dian)晕(yun))的(de)(de)范围(wei)逐渐扩(kuo)大，最后极间空(kong)气(qi)(qi)全部(bu)电(dian)(dian)(dian)(dian)(dian)离，这种现象称为电(dian)(dian)(dian)(dian)(dian)场击穿。电(dian)(dian)(dian)(dian)(dian)场击穿时，发生火花放电(dian)(dian)(dian)(dian)(dian)，电(dian)(dian)(dian)(dian)(dian)气(qi)(qi)短(duan)路(lu)，电(dian)(dian)(dian)(dian)(dian)除尘器(qi)停止工作。为了(le)保证电(dian)(dian)(dian)(dian)(dian)除尘器(qi)的(de)(de)正常运动，电(dian)(dian)(dian)(dian)(dian)晕(yun)的(de)(de)范围(wei)不宜过大，一(yi)(yi)般(ban)应局限于电(dian)(dian)(dian)(dian)(dian)晕(yun)极附(fu)近(jin)。