【電(dian)(dian)感(gan)線圈(quan)】電(dian)(dian)感(gan)線圈(quan)有哪(na)些分類 電(dian)(dian)感(gan)線圈(quan)的主要性能
電感線圈的分類
在電路中常用的電感線圈的分(fen)類大致有這么(me)幾種:
按電(dian)感(gan)形式分(fen)類:固定電(dian)感(gan)、可變電(dian)感(gan)。
按導磁(ci)體(ti)性(xing)質分類:空芯線(xian)圈、鐵氧體(ti)線(xian)圈、鐵芯線(xian)圈、銅(tong)芯線(xian)圈。
按工作性(xing)質分類(lei):天(tian)線(xian)線(xian)圈(quan)(quan)(quan)、振蕩(dang)線(xian)圈(quan)(quan)(quan)、扼(e)流(liu)線(xian)圈(quan)(quan)(quan)、陷波線(xian)圈(quan)(quan)(quan)、偏轉線(xian)圈(quan)(quan)(quan)。
按繞(rao)(rao)(rao)線(xian)結構分類:單(dan)層線(xian)圈(quan)(quan)、多(duo)層線(xian)圈(quan)(quan)、蜂房式(shi)(shi)(shi)線(xian)圈(quan)(quan)、密(mi)繞(rao)(rao)(rao)式(shi)(shi)(shi)線(xian)圈(quan)(quan)、間(jian)繞(rao)(rao)(rao)式(shi)(shi)(shi)線(xian)圈(quan)(quan)、脫胎式(shi)(shi)(shi)線(xian)圈(quan)(quan)、蜂房式(shi)(shi)(shi)線(xian)圈(quan)(quan)、亂繞(rao)(rao)(rao)式(shi)(shi)(shi)線(xian)圈(quan)(quan)。
電感線圈的主要性能
電感線圈的性能指標主要就是電感量的(de)(de)大小(xiao)。另外,繞制電(dian)感線(xian)(xian)圈(quan)(quan)的(de)(de)導線(xian)(xian)一般來說總(zong)具有一定(ding)的(de)(de)電(dian)阻,通常(chang)這(zhe)個(ge)電(dian)阻是很(hen)小(xiao)的(de)(de),可以(yi)(yi)忽(hu)略不(bu)記。但當在一些電(dian)路中流過(guo)的(de)(de)電(dian)流很(hen)大時(shi)線(xian)(xian)圈(quan)(quan)的(de)(de)這(zhe)個(ge)很(hen)小(xiao)的(de)(de)電(dian)阻就不(bu)能(neng)忽(hu)略了,因為(wei)很(hen)大的(de)(de)電(dian)流會在這(zhe)個(ge)線(xian)(xian)圈(quan)(quan)上消耗功(gong)率,引(yin)起線(xian)(xian)圈(quan)(quan)發熱(re)甚至燒壞,所以(yi)(yi)有些時(shi)候還要考慮(lv)線(xian)(xian)圈(quan)(quan)能(neng)承受的(de)(de)電(dian)功(gong)率。
電感量
電(dian)(dian)感(gan)量(liang)L表示線(xian)圈(quan)(quan)本(ben)身固有特性(xing),與(yu)電(dian)(dian)流大(da)(da)小無(wu)關。除專(zhuan)門的(de)(de)電(dian)(dian)感(gan)線(xian)圈(quan)(quan)(色碼(ma)電(dian)(dian)感(gan))外,電(dian)(dian)感(gan)量(liang)一般不專(zhuan)門標注在線(xian)圈(quan)(quan)上(shang),而以特定的(de)(de)名稱標注。電(dian)(dian)感(gan)量(liang)也稱自(zi)感(gan)系數(shu),是表示電(dian)(dian)感(gan)器(qi)產生(sheng)自(zi)感(gan)應能(neng)力的(de)(de)一個物理量(liang)。電(dian)(dian)感(gan)器(qi)電(dian)(dian)感(gan)量(liang)的(de)(de)大(da)(da)小,主要取決于線(xian)圈(quan)(quan)的(de)(de)圈(quan)(quan)數(shu)(匝(za)數(shu))、繞(rao)(rao)制(zhi)方式、有無(wu)磁(ci)心及磁(ci)心的(de)(de)材料等等。通常,線(xian)圈(quan)(quan)圈(quan)(quan)數(shu)越(yue)(yue)多、繞(rao)(rao)制(zhi)的(de)(de)線(xian)圈(quan)(quan)越(yue)(yue)密(mi)集,電(dian)(dian)感(gan)量(liang)就(jiu)越(yue)(yue)大(da)(da)。有磁(ci)心的(de)(de)線(xian)圈(quan)(quan)比(bi)無(wu)磁(ci)心的(de)(de)線(xian)圈(quan)(quan)電(dian)(dian)感(gan)量(liang)大(da)(da);磁(ci)心導磁(ci)率越(yue)(yue)大(da)(da)的(de)(de)線(xian)圈(quan)(quan),電(dian)(dian)感(gan)量(liang)也越(yue)(yue)大(da)(da)。
電感(gan)量(liang)的基本單位是(shi)亨利(簡稱亨),用(yong)字(zi)母"H"表示。常用(yong)的單位還有毫亨(mH)和微亨(μH),它們之間的關系是(shi):
1H=1000mH
1mH=1000μH
感抗
電(dian)(dian)感(gan)線圈對交(jiao)流(liu)(liu)電(dian)(dian)流(liu)(liu)阻(zu)礙作(zuo)用的大小稱感(gan)抗XL,單位是歐姆,符號(hao)Ω。它與電(dian)(dian)感(gan)量L和交(jiao)流(liu)(liu)電(dian)(dian)頻(pin)率f的關(guan)系為XL=2πfL
品質因素
品(pin)質(zhi)因素(su)Q是(shi)表示(shi)線(xian)圈(quan)(quan)質(zhi)量的(de)一(yi)個物理量,Q為(wei)感(gan)抗(kang)XL與其等(deng)(deng)效(xiao)的(de)電(dian)(dian)(dian)阻的(de)比(bi)值(zhi),即(ji):Q=XL/R。它(ta)是(shi)指電(dian)(dian)(dian)感(gan)器在某一(yi)頻(pin)率的(de)交流電(dian)(dian)(dian)壓下工(gong)作(zuo)時,所(suo)呈現的(de)感(gan)抗(kang)與其等(deng)(deng)效(xiao)損(sun)(sun)(sun)耗電(dian)(dian)(dian)阻之比(bi)。電(dian)(dian)(dian)感(gan)器的(de)Q值(zhi)越高(gao),其損(sun)(sun)(sun)耗越小,效(xiao)率越高(gao)。線(xian)圈(quan)(quan)的(de)Q值(zhi)與導線(xian)的(de)直流電(dian)(dian)(dian)阻,骨架的(de)介質(zhi)損(sun)(sun)(sun)耗,屏(ping)蔽罩(zhao)(zhao)或鐵(tie)芯引起的(de)損(sun)(sun)(sun)耗,高(gao)頻(pin)趨膚效(xiao)應的(de)影(ying)響等(deng)(deng)因素(su)有關。線(xian)圈(quan)(quan)的(de)Q值(zhi)通常(chang)為(wei)幾十到幾百。電(dian)(dian)(dian)感(gan)器品(pin)質(zhi)因數的(de)高(gao)低與線(xian)圈(quan)(quan)導線(xian)的(de)直流電(dian)(dian)(dian)阻、線(xian)圈(quan)(quan)骨架的(de)介質(zhi)損(sun)(sun)(sun)耗及鐵(tie)心、屏(ping)蔽罩(zhao)(zhao)等(deng)(deng)引起的(de)損(sun)(sun)(sun)耗等(deng)(deng)有關。
分布電容
任何電感線圈,其匝與匝之(zhi)間(jian)、層(ceng)與層(ceng)之(zhi)間(jian),線(xian)(xian)圈(quan)(quan)與參考地之(zhi)間(jian),線(xian)(xian)圈(quan)(quan)與磁屏(ping)蔽罩間(jian)等都存在(zai)一定(ding)的電(dian)容(rong),這(zhe)些(xie)電(dian)容(rong)稱為(wei)電(dian)感線(xian)(xian)圈(quan)(quan)的分(fen)布(bu)電(dian)容(rong)。若將這(zhe)些(xie)分(fen)布(bu)電(dian)容(rong)綜合(he)在(zai)一起,就成為(wei)一個與電(dian)感線(xian)(xian)圈(quan)(quan)并聯的等效電(dian)容(rong)C。分(fen)布(bu)電(dian)容(rong)的存在(zai)使線(xian)(xian)圈(quan)(quan)的Q值減小,穩定(ding)性變差,因而(er)線(xian)(xian)圈(quan)(quan)的分(fen)布(bu)電(dian)容(rong)越小越好(hao)。
額定電流
額定電(dian)(dian)(dian)(dian)流(liu)是指電(dian)(dian)(dian)(dian)感(gan)器有正常工作(zuo)時反(fan)允許通(tong)過(guo)的(de)最大電(dian)(dian)(dian)(dian)流(liu)值。若工作(zuo)電(dian)(dian)(dian)(dian)流(liu)超過(guo)額定電(dian)(dian)(dian)(dian)流(liu),則電(dian)(dian)(dian)(dian)感(gan)器就會因發熱而使(shi)性能參數發生改變,甚(shen)至還會因過(guo)流(liu)而燒(shao)毀。
允許偏差
允許(xu)偏差是指電(dian)感(gan)器上標稱的電(dian)感(gan)量與實際電(dian)感(gan)的允許(xu)誤差值。
一般用于(yu)振蕩(dang)或濾(lv)波等電路(lu)中的(de)電感器要(yao)求精(jing)度較高,允許偏(pian)(pian)差為(wei)±0.2[%]~±0.5[%];而用于(yu)耦合、高頻阻流(liu)等線圈的(de)精(jing)度要(yao)求不高;允許偏(pian)(pian)差為(wei)±10[%]~15[%]。