1、1Let power more efficient & quiet卢增艺 博士生陈为 教授、博导电气工程与自动化学院金属磁粉芯PFC电感分析和设计2010年中国电源学会技术年会，深圳2Let power more efficient & quietAC-DC模块电源及其磁元件电感磁芯材质特性分析电感线圈损耗特性考虑金属磁粉芯PFC 电感设计报告内容3Let power more efficient & quietMilan M Jovanovic, “Technology Drivers and Trends for Power Supplies in Computer/Telecom App
2、lications”, IEEE APEC2006, Plenary Session(Presentation)Milan M Jovanovic, “power supply technology-past, present, and future”, PCIM2007-China, pp. 3-152000 200620101510303540年度功率密度W/in3Server/telecom front end (single output for DPA)Desktop PS (multiple output)Notebook adapters25201580-85%92-97%87-
3、92%94-97%88-91%84-87%65-70%72-80%80-86%功率密度AC-DC电源高功率密度发展趋势4Let power more efficient & quietPFC电感要求：低损耗，大感量，小尺寸，无噪音。PFC电感设计面临的机遇和挑战AC-DC变换器(PFC)EMI 滤波器DC-DC变换器5Let power more efficient & quiet电感磁芯材质特性分析6Let power more efficient & quiet铂科系列NPFNPSPPF PPI软磁材料介紹合金材料MPP: 铁镍鉬High Flux: 铁镍Sendust: 铁硅铝FeSi:
4、 铁硅Iron Powder: 铁粉芯铁氧体材料锰锌铁氧体镍锌铁氧体非晶、纳米晶铁基钴基Magnetic alloyInsulating layer (Ceramic)7Let power more efficient & quiet10=铁氧体金属磁粉芯损耗比值Sendust 60High-Flux 60MPP 60Ferrite (3C96)0.010.1Bac (T)Pcv(W/cm3)10-410不同材质的铁芯损耗特性在铁芯损耗方面，铁氧体材料损耗最小。8Let power more efficient & quiet铁氧体材料的温度影响Pcv=750kW/m3T=0Pcv=300kW
5、/m3T=100损耗特性Bs450mT (T=25, H=250)Bs380mT (T=100, H=250)饱和特性铁芯损耗和饱和磁密随温度变化大。9Let power more efficient & quiet1 10 1000204060801001201401601802002660125160直流偏磁H(oe)单位匝数电感量 AL相同材料，不同u值，以High-Flux为例金属磁粉芯材料的饱和特性I*L=N*Ae*B10Let power more efficient & quiet金属磁粉芯材料的饱和特性不同材料，相同u值资料源自:深圳市铂科磁材有限公司A/m磁导率MPP1000
6、 2000 3000 4000 5000 6000 70000102030405060High FluxSendust11Let power more efficient & quiet铁芯损耗随时间的变化曲线%Q 随时间变化曲线铁粉芯的热老化现象电感失效12Let power more efficient & quiet磁芯材料应用小结Ferrite, Sendust, MPP, (High Flux, Iron Powder, FeSi)低 高Iron Powder, Ferrite, FeSi, Sendust, High Flux, MPP低高价格直流特性Ferrite, MPP, S
7、endust, High Flux, FeSi, Iron Powder低高铁芯损耗13Let power more efficient & quiet电感线圈损耗特性考虑14Let power more efficient & quiet气隙磁通扩散特性1. 电感量klALgg=0k为磁通扩扩散系数，与和气隙的几何尺寸有关。在很多场合气隙扩散磁通带来线圈损耗大大于铁芯损耗。扩散磁通在周边导体产生损耗，和气隙距离、导体结构相关。1357911S1S2S3S4S5S6S7S8S9S10S11S12050100150200250300350400450500550600650700xyPw2. 线
8、圈损耗128)()(42,2,sjicjipldrBrP=15Let power more efficient & quiet集中气隙与分布气隙绝缘层合金材料采用分布气隙可显著改善电感线圈损耗。16Let power more efficient & quiet环形电感的线圈损耗特点Case 1 (N=24Ts, L=5.88mH/m)Ip=1Afs=200K6mm10mm虽然没有了气隙扩散磁通损耗，但仍尽量避免出现多层绕线结构。展开示意图MMFCase 2 (N=48Ts, L=23.5mH/m)Ip=1Afs=200KLayer with the greatest loss3.76200K
9、 19.628.014.02.12Case 2R(Ohm)/Meter2.68100K400KDCFreq. Case 15.301.0617Let power more efficient & quiet金属磁粉芯PFC 电感的设计18Let power more efficient & quiet几种PFC 电路现在应用的PFC 电路形式多样，但其电感特征相似。传统PFC结构Dual Boost结构 推挽型 boost结构19Let power more efficient & quietPFC工作模式CCM DCMB工频周期 +高频开关周期20Let power more efficie
10、nt & quiet电压.电流.占空比波形0 0.002 0.004 0.006 0.00800.51Duty CycleDuty t()t0 0.002 0.004 0.006 0.00801020Average Currentiavgt()t0 0.002 0.004 0.006 0.00800.51Duty CycleDuty t()t0 0.002 0.004 0.006 0.00801020Average Currentiavgt()t0 0.002 0.004 0.006 0.0080200400Vin t()t0 0.002 0.004 0.006 0.0080200400Vin
11、 t()tVot)sin(2Vin21Duty(t)line=ft)sin(2iVinPo2(t)ilineavg=Vin=70VVin=275VseomaxfA4NVB=出现最大的交流磁密，且为常数。TsDuty(t)Lt)sin(2iVin2I(t)line=0 0.002 0.004 0.006 0.008036Ripple Currentit()0 0.002 0.004 0.006 0.008036Ripple Currentit()21Let power more efficient & quiet0 0.001 0.002 0.003 0.004 0.005 0.006 0.00
12、7 0.008 0.0091.1042.1043.1044.104Real Inductance versus DC Bias Current)t恒定电感值工频电流偏磁下的电感特性360uHVin=70V变电感0 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008 0.00905101520Ripple Current versus DC Bias Currentt考虑直流偏磁恒定电感值变电感22Let power more efficient & quietSCo RoLoiLoVinx ycv m acP C f B=DTsTs1sin_x yc
13、v s m eq acPfCf B= 方波激励下铁芯损耗计算tBtv(t)fDDfeq)1(22sin_=0 0.2 0.4 0.6 0.8 100.511.522.5PpulsePower loss factor, k, with same Bm and fsDutyPsink=23Let power more efficient & quietPFC电感设计流程Start输入设计规格，包括 Vin, Vo, Io, fs, I等计算所需最小电感量选择合适材料选择合适铁芯尺寸(AP 法)根据电流密度或磁场强度计算允许匝数给出铁芯损耗，绕组损耗和总损耗判别温升要求电气特性检验( IImax,或
14、者 BBmax)不同输入电压下电流纹波小于给定值ucmkJBEAPmax2=考虑直流偏磁下电感值下降24Let power more efficient & quietCCM模式下电流波形0.002 0.004 0.006 0.008010203040tiL (t)4.1044.2.1044.4.1044.6.1044.8.1042.533.544.5Current of the choketDC fs谐波电流恒频模式下谐波特征DCfs 2fs2fsDCMB变频模式下谐波特征谐波电流25Let power more efficient & quiet()()22 221wrmswp pwRIP
15、LC CR=+PFC电感寄生参数影响LwRwCp改进前谐振导致电感损耗增加，并且影响半导体器件开关损耗。改进后21010 41010 61010 81010 110901020304050CpLw=1mHRw=10mIrms=10AIrms26Let power more efficient & quiet周围磁场X 分量分布理想均匀绕组没有磁场扩散非均匀绕组有磁场扩散BFerrite PowderPFC电感磁场泄露便于绕线，磁场泄露27Let power more efficient & quiet欢迎莅临四号馆A103展位参观指导！让电更纯静Let power more efficient & quiet铂科磁材28Let power more efficient & quiet谢谢！
