電(dian)(dian)(dian)(dian)感(gan)器(qi)(qi)（Inductor）是能(neng)(neng)夠把電(dian)(dian)(dian)(dian)能(neng)(neng)轉化為磁能(neng)(neng)而存儲起來的元件。電(dian)(dian)(dian)(dian)感(gan)器(qi)(qi)的結構類似于變(bian)壓(ya)器(qi)(qi)，但只有一(yi)個繞組。電(dian)(dian)(dian)(dian)感(gan)器(qi)(qi)具有一(yi)定的電(dian)(dian)(dian)(dian)感(gan)，它(ta)只阻礙電(dian)(dian)(dian)(dian)流(liu)(liu)的變(bian)化。如果電(dian)(dian)(dian)(dian)感(gan)器(qi)(qi)在沒(mei)有電(dian)(dian)(dian)(dian)流(liu)(liu)通過的狀態(tai)下(xia)，電(dian)(dian)(dian)(dian)路接通時(shi)它(ta)將(jiang)試(shi)(shi)圖阻礙電(dian)(dian)(dian)(dian)流(liu)(liu)流(liu)(liu)過它(ta);如果電(dian)(dian)(dian)(dian)感(gan)器(qi)(qi)在有電(dian)(dian)(dian)(dian)流(liu)(liu)通過的狀態(tai)下(xia)，電(dian)(dian)(dian)(dian)路斷開時(shi)它(ta)將(jiang)試(shi)(shi)圖維持電(dian)(dian)(dian)(dian)流(liu)(liu)不變(bian)。電(dian)(dian)(dian)(dian)感(gan)器(qi)(qi)又稱(cheng)扼(e)流(liu)(liu)器(qi)(qi)、電(dian)(dian)(dian)(dian)抗(kang)(kang)器(qi)(qi)、動(dong)態(tai)電(dian)(dian)(dian)(dian)抗(kang)(kang)器(qi)(qi)。

電感這(zhe)個元(yuan)件在電子(zi)電路中是(shi)經常見到的(de)(de)，我們炒菜用的(de)(de)電磁爐里(li)面(mian)有線圈盤它是(shi)特(te)制的(de)(de)電感、電源變壓(ya)器、電流互感器以及扼流圈都是(shi)電感。它在電路中一(yi)般(ban)起到濾波(bo)、扼流、調諧、延時、耦(ou)合(he)、補(bu)償等(deng)很多作用，來(lai)說說電感是(shi)如何進行充(chong)放電的(de)(de)。

電感的充電原理

為了能(neng)夠清楚表述(shu)充(chong)(chong)電(dian)(dian)(dian)的(de)(de)(de)原理，我(wo)們可以用下面的(de)(de)(de)電(dian)(dian)(dian)路模型來進行說明問(wen)題。當(dang)我(wo)們把開關撥到1的(de)(de)(de)位置(zhi)的(de)(de)(de)時候(hou)，由于(yu)電(dian)(dian)(dian)感(gan)的(de)(de)(de)自感(gan)應原理，會(hui)建立一(yi)個左正右負的(de)(de)(de)感(gan)應電(dian)(dian)(dian)動勢來阻(zu)礙電(dian)(dian)(dian)源對線(xian)圈的(de)(de)(de)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流，此時電(dian)(dian)(dian)感(gan)線(xian)圈L里的(de)(de)(de)電(dian)(dian)(dian)流會(hui)慢(man)慢(man)增大(da)，與電(dian)(dian)(dian)感(gan)線(xian)圈的(de)(de)(de)燈(deng)泡此時的(de)(de)(de)亮(liang)度會(hui)慢(man)慢(man)變(bian)亮(liang)。從這個漸(jian)亮(liang)的(de)(de)(de)過程我(wo)們可以推測到電(dian)(dian)(dian)感(gan)總(zong)是阻(zu)礙自身(shen)電(dian)(dian)(dian)流的(de)(de)(de)變(bian)化的(de)(de)(de)。

電感的放電原理

當我(wo)們把開關(guan)撥到2的(de)位(wei)置(zhi)時(shi)候會(hui)發(fa)現燈泡(pao)A并不(bu)會(hui)立即(ji)熄滅(mie)，而是(shi)慢(man)慢(man)熄滅(mie)的(de)。這(zhe)時(shi)候電(dian)(dian)(dian)感線圈相(xiang)當于一個(ge)電(dian)(dian)(dian)動(dong)勢，其(qi)電(dian)(dian)(dian)感的(de)左邊是(shi)正極右邊是(shi)負極。電(dian)(dian)(dian)感儲存的(de)電(dian)(dian)(dian)能逐漸被燈泡(pao)消耗完(wan)。所(suo)以我(wo)們看(kan)到燈的(de)亮(liang)度由亮(liang)慢(man)慢(man)變暗(an)最后熄滅(mie)這(zhe)樣一個(ge)漸進(jin)的(de)過程。從這(zhe)個(ge)電(dian)(dian)(dian)感的(de)充電(dian)(dian)(dian)放電(dian)(dian)(dian)過程可以看(kan)出(chu)，電(dian)(dian)(dian)感中的(de)電(dian)(dian)(dian)流是(shi)不(bu)能突變的(de)，因(yin)此(ci)我(wo)們常(chang)常(chang)稱電(dian)(dian)(dian)感元件是(shi)“慣(guan)性元件”。