在采購容阻感等(deng)電(dian)(dian)(dian)子元器(qi)(qi)件(jian)(jian)時，我們經常會接觸(chu)到純電(dian)(dian)(dian)阻電(dian)(dian)(dian)路(lu)(lu)這個名詞，本文就來(lai)為大家科普(pu)，純電(dian)(dian)(dian)阻電(dian)(dian)(dian)路(lu)(lu)的(de)(de)定(ding)義以(yi)及相關的(de)(de)知識(shi)，簡單來(lai)說，純電(dian)(dian)(dian)阻電(dian)(dian)(dian)路(lu)(lu)是由純電(dian)(dian)(dian)阻元件(jian)(jian)構(gou)成的(de)(de)電(dian)(dian)(dian)路(lu)(lu)，其中只包括電(dian)(dian)(dian)阻器(qi)(qi)等(deng)電(dian)(dian)(dian)阻元件(jian)(jian)，而不包括電(dian)(dian)(dian)容器(qi)(qi)、電(dian)(dian)(dian)感器(qi)(qi)或其他(ta)被稱(cheng)為“復雜阻抗”的(de)(de)元件(jian)(jian)。

　　什么是純電阻電路

　　所謂的(de)(de)純(chun)電(dian)(dian)(dian)(dian)阻電(dian)(dian)(dian)(dian)路，就是(shi)電(dian)(dian)(dian)(dian)路中不存(cun)在電(dian)(dian)(dian)(dian)感、電(dian)(dian)(dian)(dian)容(rong)這類儲能且不消(xiao)耗(hao)功(gong)率的(de)(de)無功(gong)元件(jian)(jian)，只(zhi)有(you)消(xiao)耗(hao)或產生(sheng)功(gong)率的(de)(de)器(qi)件(jian)(jian)，純(chun)粹(cui)的(de)(de)反電(dian)(dian)(dian)(dian)勢(shi)負載也(ye)可以歸并(bing)到消(xiao)耗(hao)或產生(sheng)功(gong)率器(qi)件(jian)(jian)。比如交流感應(ying)電(dian)(dian)(dian)(dian)動機，由于(yu)內部有(you)電(dian)(dian)(dian)(dian)感和反電(dian)(dian)(dian)(dian)勢(shi)，他(ta)不可能是(shi)純(chun)電(dian)(dian)(dian)(dian)阻電(dian)(dian)(dian)(dian)路，內部有(you)電(dian)(dian)(dian)(dian)阻、電(dian)(dian)(dian)(dian)感和反電(dian)(dian)(dian)(dian)勢(shi)。

圖：純電阻電路

　　在這樣的電(dian)(dian)路中(zhong)(zhong)，電(dian)(dian)流和電(dian)(dian)壓(ya)的關系(xi)遵循(xun)歐姆定律，即電(dian)(dian)流大小與電(dian)(dian)壓(ya)成正比，比例常數為電(dian)(dian)路的總電(dian)(dian)阻(zu)，因此，在純(chun)電(dian)(dian)阻(zu)電(dian)(dian)路中(zhong)(zhong)，電(dian)(dian)流和電(dian)(dian)壓(ya)的相位是相同的。

　　純電阻電路(lu)(lu)通常用于(yu)電路(lu)(lu)分析的基礎中，因為(wei)它們(men)相對簡單而且易于(yu)處理，但是(shi)，實際電路(lu)(lu)中很少完(wan)全由純電阻元件構(gou)成，因為(wei)電容器(qi)和(he)電感器(qi)在許多(duo)電路(lu)(lu)應用中都是(shi)必需(xu)的。

　　純電(dian)阻電(dian)路(lu)就(jiu)是除交變電(dian)源外(wai)，只有(you)電(dian)阻元件的電(dian)路(lu)，或(huo)有(you)電(dian)感和(he)電(dian)容元件，但它們對(dui)電(dian)路(lu)的影響(xiang)可(ke)忽略(lve)，電(dian)壓與(yu)電(dian)流同(tong)頻(pin)且(qie)同(tong)相位，電(dian)阻將(jiang)從電(dian)源獲得的能量全部轉(zhuan)變成內能，這種電(dian)路(lu)就(jiu)叫(jiao)做純電(dian)阻電(dian)路(lu)。

　　例如：電燈，電烙(luo)鐵，熨斗，等(deng)等(deng)，他們只(zhi)是(shi)(shi)發(fa)熱，它們都是(shi)(shi)純電阻(zu)電路(lu)。但是(shi)(shi)，發(fa)動機，電風扇等(deng)，除了發(fa)熱以外，還(huan)對外做功，所以這些是(shi)(shi)非純電阻(zu)電路(lu)。基(ji)本上，只(zhi)要電能除了轉化(hua)為熱能以外沒有其他能的轉化(hua)，此(ci)電路(lu)為純電阻(zu)電路(lu)。

　　白(bai)熾燈(deng)把(ba)99%以上的電(dian)(dian)能都轉化(hua)為(wei)熱能，只有很(hen)少(shao)很(hen)少(shao)轉化(hua)為(wei)光能，所(suo)以，在中(zhong)學(xue)電(dian)(dian)學(xue)計算(suan)中(zhong)，白(bai)熾燈(deng)也近似看(kan)做純電(dian)(dian)阻(zu)。而節能燈(deng)則大(da)部分能量轉換成(cheng)了光能所(suo)以節能燈(deng)屬于非純電(dian)(dian)阻(zu)電(dian)(dian)路，這也是(shi)為(wei)什(shen)么白(bai)熾燈(deng)遠(yuan)比節能燈(deng)耗電(dian)(dian)的原因(yin)(節能燈(deng)幾乎將電(dian)(dian)能全部轉化(hua)為(wei)了光能)

　　準確來說，歐(ou)姆定律(lv)全部式(shi)子焦(jiao)耳定律(lv)中的所有變形式(shi)如Q=U^2/RtQ=W=Pt=UIt等都能在(zai)純電阻(zu)電路中使用。

　　了(le)解了(le)純電(dian)(dian)阻電(dian)(dian)路(lu)后，與之對應的非純電(dian)(dian)阻電(dian)(dian)路(lu)又是什么呢(ni)？

　　什么是非純電阻電路

　　非(fei)純電(dian)阻(zu)(zu)電(dian)路(lu)是指電(dian)路(lu)中除了電(dian)阻(zu)(zu)器(qi)(qi)以外(wai)還有其他電(dian)性元件（如電(dian)容器(qi)(qi)、電(dian)感器(qi)(qi)等）的電(dian)路(lu)，這些(xie)元件在電(dian)路(lu)中的作用是用來調節電(dian)路(lu)的頻率響應(ying)、相位差、電(dian)流、電(dian)壓等參數，從而(er)實現電(dian)路(lu)的各(ge)種功能。

　　在(zai)非純(chun)電(dian)(dian)(dian)(dian)阻電(dian)(dian)(dian)(dian)路中(zhong)，電(dian)(dian)(dian)(dian)容器(qi)和電(dian)(dian)(dian)(dian)感器(qi)是最常(chang)見的電(dian)(dian)(dian)(dian)性元(yuan)件(jian)，電(dian)(dian)(dian)(dian)容器(qi)是由(you)(you)兩個導體板之間隔一定距離的電(dian)(dian)(dian)(dian)介質組成，它(ta)的作用是存儲電(dian)(dian)(dian)(dian)荷并在(zai)電(dian)(dian)(dian)(dian)路中(zhong)產(chan)生(sheng)電(dian)(dian)(dian)(dian)場，電(dian)(dian)(dian)(dian)感器(qi)則是由(you)(you)繞制導線而成的電(dian)(dian)(dian)(dian)感元(yuan)件(jian)，它(ta)的作用是存儲電(dian)(dian)(dian)(dian)磁能并在(zai)電(dian)(dian)(dian)(dian)路中(zhong)產(chan)生(sheng)磁場。

　　在(zai)非純電(dian)(dian)阻電(dian)(dian)路(lu)(lu)中，電(dian)(dian)容器(qi)和電(dian)(dian)感器(qi)都會(hui)影響電(dian)(dian)路(lu)(lu)的頻率響應，電(dian)(dian)容器(qi)對低(di)頻信(xin)(xin)(xin)號(hao)的傳遞(di)具有很好(hao)的通路(lu)(lu)特(te)性，而對高頻信(xin)(xin)(xin)號(hao)的傳遞(di)則具有很好(hao)的阻斷特(te)性。因(yin)此，在(zai)濾(lv)(lv)(lv)波電(dian)(dian)路(lu)(lu)中，可以使(shi)用電(dian)(dian)容器(qi)來濾(lv)(lv)(lv)掉高頻噪聲信(xin)(xin)(xin)號(hao)，從而實現信(xin)(xin)(xin)號(hao)的濾(lv)(lv)(lv)波；電(dian)(dian)感器(qi)則相反，對高頻信(xin)(xin)(xin)號(hao)的傳遞(di)具有很好(hao)的通路(lu)(lu)特(te)性，而對低(di)頻信(xin)(xin)(xin)號(hao)的傳遞(di)則具有很好(hao)的阻斷特(te)性。因(yin)此，在(zai)濾(lv)(lv)(lv)波電(dian)(dian)路(lu)(lu)中，可以使(shi)用電(dian)(dian)感器(qi)來濾(lv)(lv)(lv)掉低(di)頻噪聲信(xin)(xin)(xin)號(hao)。

　　此外，非純電(dian)(dian)阻電(dian)(dian)路(lu)中還有一些其(qi)他的(de)(de)電(dian)(dian)性(xing)元(yuan)件(jian)，比如二(er)(er)極(ji)管(guan)、三極(ji)管(guan)等半(ban)導體元(yuan)件(jian)，這些元(yuan)件(jian)可以實現電(dian)(dian)路(lu)的(de)(de)放大、整(zheng)流(liu)、開(kai)關等功(gong)能。例如，在放大電(dian)(dian)路(lu)中，可以使用(yong)三極(ji)管(guan)來放大輸入信號(hao)，從而實現信號(hao)的(de)(de)放大，在整(zheng)流(liu)電(dian)(dian)路(lu)中，可以使用(yong)二(er)(er)極(ji)管(guan)來將輸入信號(hao)中的(de)(de)負半(ban)周去除，從而實現信號(hao)的(de)(de)整(zheng)流(liu)。

　　總之，非純(chun)電(dian)(dian)(dian)(dian)阻電(dian)(dian)(dian)(dian)路(lu)是一種(zhong)復雜的(de)電(dian)(dian)(dian)(dian)路(lu)類(lei)型，其(qi)中(zhong)包含了各(ge)種(zhong)不同的(de)電(dian)(dian)(dian)(dian)性元(yuan)件，這些元(yuan)件共(gong)同作用(yong)于電(dian)(dian)(dian)(dian)路(lu)中(zhong)，從(cong)而實現電(dian)(dian)(dian)(dian)路(lu)的(de)各(ge)種(zhong)功能，在實際應用(yong)中(zhong)，非純(chun)電(dian)(dian)(dian)(dian)阻電(dian)(dian)(dian)(dian)路(lu)被廣(guang)泛應用(yong)于通信(xin)、控(kong)制、功率(lv)等(deng)領域，是電(dian)(dian)(dian)(dian)子技術(shu)中(zhong)不可或缺的(de)一部(bu)分。