 | Ae：有效磁粉芯面積（cm2）與磁芯的橫截面積相等（cross section area） le:有效磁路長度或稱平均磁路長度（cm）（mean magnetic path length） V:磁芯體積：（cm3）(core volume) OD：磁芯外徑（cm）（outside diameter of core） ID:磁芯內徑（cm）(inside diameter of core) Ht：磁芯高度（cm） W:磁芯最小窗口面積（cm2） 1英寸（inches）=103mil=25.4mm |
磁導(dao)率是磁滯回線上任何點所對應的B與H的比值。
In magnetics,permeability is the ability of a material to conduct flux.The magnetitude of the permeability at a given induction is a measure of the ease with which a core material can be magnetized to that induction.It is defined as the ratio of the flux density Bto the magnetizing force H.
 | μe：有效磁導率（無量綱）permeability B:磁通量密度（高斯Gauss）flux density(Gauss) H:磁場強度（奧斯特Oe）magnetizing(Oe) |
每種尺(chi)寸(cun)磁(ci)(ci)粉(fen)芯的(de)額定電(dian)(dian)感量都與其有(you)效磁(ci)(ci)導率有(you)關，有(you)效磁(ci)(ci)導率僅作(zuo)參考(kao)環型磁(ci)(ci)芯的(de)電(dian)(dian)感測(ce)試是依(yi)(yi)均勻分布的(de)單層(ceng)繞組作(zuo)測(ce)試依(yi)(yi)據，以非均勻分布而少圈數(shu)的(de)磁(ci)(ci)芯作(zuo)測(ce)試會產(chan)生比預期要大的(de)電(dian)(dian)感讀數(shu)。
Neu Flux Cores的電感系數值是以1000圈時為測試依據，其(qi)中電感系數偏差(cha)通(tong)常在±8%之(zhi)間(jian)。
The inductance of a wound core at a given number of turns is calculated using the following formula | L=0.4πμeN2Ae*10-2/le Ln=Al&N<2>*10-3L:電感量（μH）1H=103mH=106μH=109nH inductance(μH) Al：額定電感量（nH/N2）nominal Inductance(nH/N2) μe:有效磁芯截面積 effective cores section area(cm2) Ae:有效磁路長度 mean magnetic path length(cm) N:線圈數： number of turns Ln:在N圈時的電感量（μH）Inductance at N turns(μH) |
安培(pei)定(ding)律揭示了磁場(chang)強度(du)（H）與(yu)電流、圈數和磁路長度(du)之間(jian)的(de)關系。
Ampere's Law relates magnetizing force(H)to current,number of turns and magnetic path
 | H:磁場強(qiang)度（Oersteds）magnetizing force(oersteds) N:圈數(shu) number of turns I:電流（A）peak magnetizing current(amperes) Le:磁路(lu)長度（cm） mean magnetic path length(cm) 1Oersted=0.7958A/cm |
Q值(zhi)是指電感(gan)(gan)器電抗與有效(xiao)(xiao)電阻的(de)比值(zhi)，它反映了(le)該(gai)電感(gan)(gan)的(de)質量(liang)。對于電源濾波器而言，Q值(zhi)提高就意味著截止更快，衰減比更高和諧(xie)效(xiao)(xiao)果(guo)更好，Q值(zhi)的(de)大小主要由電感(gan)(gan)線(xian)圈的(de)分(fen)布(bu)電容(rong)所(suo)決定。如果(guo)忽略分(fen)布(bu)電容(rong)引起的(de)自諧(xie)振效(xiao)(xiao)果(guo)，可以(yi)用以(yi)下公式計(ji)算電感(gan)(gan)器Q值(zhi)
The Qfactor is defined as the ratio of reactance to the effective resistance for inductor and thus indicates its quality.The Qof wound core can be calculated using the following formula,when neglecting the effects of self-resonance caused by the distributed capacitance resulting from the differential voltage between adjacent turns.
 | Q:品質因數 quality factor L:電感量（H）inductance(henries) ω:2πf(Hz)2π frequency(hertz) Rdc:繞線直流電阻（Ω）DC winding resistance(ohms) Rac:由(you)于(yu)磁粉芯損耗而產生的(de)阻抗（Ω）resistance due to core loss(ohms) Rcd:由于(yu)繞(rao)線中介電損耗(hao)而產生的阻抗(kang)（Ω）resistance due to winding dielectric loss(ohms) |
磁(ci)通密度(du)的(de)大(da)小影(ying)響磁(ci)粉(fen)芯(xin)的(de)損耗值(zhi)和(he)磁(ci)導率(lv)。除非另(ling)有說(shuo)明(ming)，本(ben)(ben)樣本(ben)(ben)中所列舉的(de)數據都是基于正弦波(bo)形和(he)最(zui)(zui)大(da)磁(ci)通密度(du)（峰值(zhi)）得出(chu)的(de)。Bpk指穿過(guo)磁(ci)粉(fen)芯(xin)橫截面各(ge)部分(fen)平均磁(ci)通密度(du)值(zhi)的(de)最(zui)(zui)大(da)值(zhi)。事實上，通過(guo)磁(ci)粉(fen)芯(xin)內徑附(fu)近(jin)的(de)磁(ci)通密度(du)值(zhi)高，而磁(ci)粉(fen)芯(xin)外徑附(fu)近(jin)的(de)磁(ci)通密度(du)值(zhi)低。
The corresponding parameter for the induces magnetic field in an area perpendicular to the flux density is determined by the field strength permeability of the medium in which it is measured.
 | Bpk:最大磁通密度峰值（高斯Gauss）maximum flux density(gauss) Erms:通過繞正弦電壓有效值（Vrms）sinusoidal RMS voltage across winding(Vrms) N:圈數 number of turns Ae:有效磁粉芯截面積（cm2）cross section area(cm2) f：正弦波形電壓頻率（Hz）frequency(hertz) 1特斯拉（T）=104高斯（）Gauss=103mT |
磁(ci)(ci)(ci)(ci)芯(xin)損(sun)耗(hao)是(shi)磁(ci)(ci)(ci)(ci)芯(xin)材料內交替(ti)磁(ci)(ci)(ci)(ci)場(chang)引致的(de)(de)結果。磁(ci)(ci)(ci)(ci)芯(xin)損(sun)耗(hao)有三部分組成：磁(ci)(ci)(ci)(ci)滯(zhi)損(sun)耗(hao)、剩磁(ci)(ci)(ci)(ci)損(sun)耗(hao)和(he)渦流(liu)損(sun)耗(hao)。在(zai)高頻(pin)條件下(xia)，渦流(liu)損(sun)耗(hao)是(shi)主(zhu)要(yao)損(sun)耗(hao)，而(er)低頻(pin)下(xia)磁(ci)(ci)(ci)(ci)滯(zhi)損(sun)耗(hao)則(ze)是(shi)主(zhu)要(yao)損(sun)耗(hao)。而(er)各(ge)種(zhong)損(sun)耗(hao)形式(shi)在(zai)總損(sun)耗(hao)中所占的(de)(de)比例也會受(shou)到(dao)磁(ci)(ci)(ci)(ci)通密度的(de)(de)影響，受(shou)到(dao)高溫熱老化影響的(de)(de)是(shi)磁(ci)(ci)(ci)(ci)芯(xin)損(sun)耗(hao)的(de)(de)渦流(liu)部分。
Powder cores have low hysteres is loss,minimizing signal distoion,and low residual loss.The total core loss at low.The core loss is calculated from the following legg's equation.
 | Rac:由磁芯損(sun)耗(hao)產(chan)生的有效電阻（Ω）resistance due tp core loss(ohms) μe:有效磁導率 permeability L:電感量（H）inductance(H) a:磁滯損(sun)耗系數 hysteresis loss coefficient Bpk:AC磁通(tong)密度峰值（高(gao)斯Gauss）maximum flux density(gauss) c:剩磁損耗系數 residual loss coefficient f:頻率（Hz）frequency(hertz) e:渦流損(sun)耗(hao)系數：eddy loss coefficient |