CN101477151B - Value quantitative method for inductor in EMI filter - Google Patents

Value quantitative method for inductor in EMI filter Download PDF

Info

Publication number
CN101477151B
CN101477151B CN2008102390961A CN200810239096A CN101477151B CN 101477151 B CN101477151 B CN 101477151B CN 2008102390961 A CN2008102390961 A CN 2008102390961A CN 200810239096 A CN200810239096 A CN 200810239096A CN 101477151 B CN101477151 B CN 101477151B
Authority
CN
China
Prior art keywords
inductance
value
electromagnetic interface
interface filter
emi filter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN2008102390961A
Other languages
Chinese (zh)
Other versions
CN101477151A (en
Inventor
闫照文
王龙峰
陈文青
苏东林
王�义
侯燕春
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beihang University
Original Assignee
Beihang University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beihang University filed Critical Beihang University
Priority to CN2008102390961A priority Critical patent/CN101477151B/en
Publication of CN101477151A publication Critical patent/CN101477151A/en
Application granted granted Critical
Publication of CN101477151B publication Critical patent/CN101477151B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

The invention discloses a value-taking quantification method for inductance in an EMI filter. The quantification method satisfies an inductance quantification model Lr=L0[mu]p according to the relative magnetic permeability [mu]r, the initial magnetic permeability change rate [mu]p and an initial inductance value L0, and L0 is equal to [mu]r[mu]0n<2>piR<2>1, thereby obtaining index values needed by the inductance L when the EMI filter is designed. The inductance quantification model Lr is equal to L0[mu]p designed by the method, when the EMI filter is arranged between a power supply and a load, the EMI filter can conveniently obtain an accurate value of the inductance L when the EMI filter is designed according to the filtering requirement needed by the load. The method eliminates the gap between functions of the filter and design indexes caused by the inaccuracy of an inductance value when the prior EMI filter selects the inductance.

Description

The value quantitative method of inductance in the electromagnetic interface filter
Technical field
The present invention relates to a kind of electromagnetic interface filter, more particularly say, be meant a kind of value quantitative method that is used for the power-supply filter inductance on the air electronics.
Background technology
The equivalent electrical circuit of the power-supply filter on the air electronics is shown in Figure 1, and among the figure, inductance L and capacitor C constitute electromagnetic interface filter, and 1 end of inductance L is connected on the positive pole of power supply, is in series with capacitor C between 2 ends of inductance L and the power cathode.Inductance L is made of soft magnetic ferrite and coil (copper cash).
In electronic equipment and electronic product, inductance L is as the important component part of electromagnetic interface filter aspect the Conduction Interference that suppresses the electromagnetic interference (EMI) signal, and its saturation characteristic directly has influence on the performance of electromagnetic interface filter.In the method for traditional calculating electromagnetic interface filter inductance saturation characteristic, for the direct current biasing I of inductance L DWith high interference frequency f HighBetween variation be separately to consider, there is certain error in electromagnetic interface filter in electromagnetic interface filter when this will cause design and the use on filtering characteristic, this error can cause the leakage of electromagnetic interference (EMI), thereby influences the Electro Magnetic Compatibility of whole electric equipment or electronic product.
Summary of the invention
The objective of the invention is to propose a kind of direct current biasing I that in electromagnetic interface filter, considers simultaneously DHigh interference frequency f HighChange the value quantitative methods of inductance L down.By inductance quantitative model L r=L 0μ pThe electromagnetic interface filter of designing has improved the filtering characteristic of electromagnetic interface filter, uses power supply for load better protection is provided.
The present invention is the value quantitative method of inductance in the electromagnetic interface filter, it is characterized in that: this quantivative approach is according to relative permeability μ r, initial permeability rate of change μ p, initial inductance value L 0Be satisfied with inductance quantitative model L r=L 0μ p, and L 0=μ rμ 0n 2π R 2L, thus the required desired value of inductance L obtained during electromagnetic interface filter in design.
The value quantitative method of inductance in the described electromagnetic interface filter is by inductance quantitative model L r=L 0μ pThe quantitative step of carrying out the value of inductance L in the electromagnetic interface filter is:
The first step:, choose inductance according to the requirement of electromagnetic interface filter output-index; And obtain the relative permeability μ of selected inductance by tabling look-up r
Second step: adopt inductance formula L 0=μ rμ 0n 2π R 2L obtains initial inductance value L 0
The 3rd step: adopt magnetic field intensity formula H=0.4 π NI/l to obtain initial permeability rate of change μ pAmong the described magnetic field intensity formula H=0.4 π NI/l, N represents the number of turn of telefault, and I represents the direct current biasing I of power supply output DSize;
The 4th step: merge the initial inductance value L that second step obtained 0With the 3rd initial permeability rate of change μ that obtains of step pSet up inductance quantitative model L r=L 0μ p, obtain the inductance value that inductance L meets in electromagnetic interface filter.
The advantage of the value quantitative method of inductance in the electromagnetic interface filter of the present invention: (1) adopts digital means modeling L r=L 0μ pMode makes electromagnetic interface filter at design phase become more convenient, easy, highly versatile.(2) adopted inductance quantitative model L r=L 0μ pThe electromagnetic interface filter of designing has improved the filtering characteristic of electromagnetic interface filter, uses power supply for load better protection is provided.(3) considered the direct current biasing I of electromagnetic interface filter in the modeling simultaneously DHigh interference frequency f HighChange inductance L changing condition down, make the electromagnetic interface filter output accuracy height of design, can improve Electromagnetic Compatibility of Power Electronics.
Description of drawings
Fig. 1 is the equivalent electrical circuit of electromagnetic interface filter.
Fig. 2 is the ferritic magnetic spectrum of inductance in the electromagnetic interface filter of the present invention.
Fig. 3 is the change curve of ferrite relative permeability rate of change in the inductance.
Embodiment
The present invention is described in further detail below in conjunction with drawings and Examples.
The present invention is a kind of inductance value quantivative approach to inductance in the electromagnetic interface filter, and this quantivative approach is according to relative permeability μ r, initial permeability rate of change μ p, initial inductance value L 0Be satisfied with inductance quantitative model L r=L 0μ p, and L 0=μ rμ 0n 2π R 2L, thus the required desired value of inductance L obtained during electromagnetic interface filter comparatively easily in design.Described inductance formula L 0=μ rμ 0n 2π R 2Among the l, n represents the density of coil, and R represents the radius of coil, and l represents the length of coil.Inductance L is made of soft magnetic ferrite and coil (copper cash).
In the present invention, described relative permeability μ rBe meant the selected material of inductance L (soft magnetic ferrite) magnetic permeability μ and permeability of vacuum μ 0Ratio, i.e. μ r=μ/μ 0The magnetic spectrum of described soft magnetic ferrite as shown in Figure 2.
In the present invention, initial inductance value L 0Be meant the high interference frequency f of inductance L filtering in electromagnetic interface filter HighThe inductance value of following inductance L.
In the present invention, initial permeability rate of change μ pBe meant that the selected material of inductance L (soft magnetic ferrite) is at direct current biasing I DThe running parameter of the magnetic permeability under (unit is A) condition.This magnetic permeability running parameter obtains by checking the magnetic spectrum curve after can calculating magnetic field intensity by the DC current of power supply output.This magnetic spectrum curve as shown in Figure 3, different ferrites has different magnetic spectrum curves.
The present invention is by inductance quantitative model L r=L 0μ pThe quantitative step of carrying out the value of inductance L in the electromagnetic interface filter is:
The first step:, choose inductance according to the requirement of electromagnetic interface filter output-index; And obtain the relative permeability μ of selected inductance by tabling look-up r
Second step: adopt inductance formula L 0=μ rμ 0n 2π R 2L obtains initial inductance value L 0
The 3rd step: adopt magnetic field intensity formula H=0.4 π NI/l to obtain initial permeability rate of change μ pAmong the described magnetic field intensity formula H=0.4 π NI/l, N represents the number of turn of telefault, and I represents the direct current biasing I of power supply output DSize;
The 4th step: merge the initial inductance value L that second step obtained 0With the 3rd initial permeability rate of change μ that obtains of step pSet up inductance quantitative model L r=L 0μ p, obtain the inductance value that inductance L meets in electromagnetic interface filter.
The inductance quantitative model L that the present invention designs r=L 0μ p, when between power supply and load electromagnetic interface filter being arranged, filtering requirements that can be required according to load can conveniently obtain the exact value of inductance L during electromagnetic interface filter in design.Overcome traditional E MI wave filter when selecting inductance, because the out of true of inductance value, filter function that causes and the gap between design objective.
Embodiment:
Inductance L is according to the requirement of inductance value in the electromagnetic interface filter circuit, the relative permeability μ of the soft magnetic ferrite of selecting for use rBe 100000, the Henry length interior loop density n that designs is 1000 circles/m, and the inductance radius R is 3mm, and inductive length l is 1cm, because the deviser does not consider the direct current biasing I of inductance L DWith high interference frequency f HighTo the influence of inductance value, when inductance L is operated in direct current biasing 5A, in the time of the highest frequency filtering 500MHz, owing to become 80000 under the relative permeability 500MHz, the relative permeability rate of change becomes μ pFor 0.9, inductance value can not reach the requirement of 12mH.In order to satisfy the requirement of inductance value, the strain of inductance radius R is 3.5mm, and inductive length becomes 1.2cm, could satisfy the requirement of the 12mH of inductance value when design.
Adopted inductance quantitative model L of the present invention r=L 0μ pThe electromagnetic interface filter of designing has improved the filtering characteristic of electromagnetic interface filter, uses power supply for load better protection is provided.

Claims (1)

1. the value quantitative method of inductance in the electromagnetic interface filter, it is characterized in that: the quantitative step of described inductance value is:
The first step:, choose inductance according to the requirement of electromagnetic interface filter output-index; And obtain the relative permeability μ of selected inductance by tabling look-up r
Second step: adopt inductance formula L 0=μ rμ 0n 2π R 2L obtains initial inductance value L 0μ 0The expression permeability of vacuum, n represents the density of coil, and R represents the radius of coil, and l represents the length of coil;
The 3rd step: adopt magnetic field intensity formula H=0.4 π NI/l to obtain initial permeability rate of change μ pAmong the described magnetic field intensity formula H=0.4 π NI/l, N represents the number of turn of telefault, and I represents the direct current biasing I of power supply output DSize;
The 4th step: merge the initial inductance value L that second step obtained 0With the 3rd initial permeability rate of change μ that obtains of step pSet up inductance quantitative model L r=L 0μ p, obtain the inductance value that inductance L meets in electromagnetic interface filter.
CN2008102390961A 2008-12-08 2008-12-08 Value quantitative method for inductor in EMI filter Active CN101477151B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2008102390961A CN101477151B (en) 2008-12-08 2008-12-08 Value quantitative method for inductor in EMI filter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2008102390961A CN101477151B (en) 2008-12-08 2008-12-08 Value quantitative method for inductor in EMI filter

Publications (2)

Publication Number Publication Date
CN101477151A CN101477151A (en) 2009-07-08
CN101477151B true CN101477151B (en) 2011-05-04

Family

ID=40837896

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2008102390961A Active CN101477151B (en) 2008-12-08 2008-12-08 Value quantitative method for inductor in EMI filter

Country Status (1)

Country Link
CN (1) CN101477151B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101629980B (en) * 2009-09-10 2011-04-27 南京师范大学 Method for testing performance of EMI filter based on scattering parameter
CN102175928B (en) * 2011-01-24 2012-12-19 北京航空航天大学 Method for selecting amplitude-frequency curve characteristic points in electromagnetic compatibility test

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1688003A (en) * 2005-06-23 2005-10-26 安泰科技股份有限公司 Anti-DC component current transformer core and mfg. method and use thereof

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1688003A (en) * 2005-06-23 2005-10-26 安泰科技股份有限公司 Anti-DC component current transformer core and mfg. method and use thereof

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
季彩瑞等.大功率工业磁芯电感测量方法探讨.《电源技术应用》.2008,第11卷(第7期),45-46. *
王全保等.软磁铁氧体的磁导率.《实用电子变压器材料器件手册》.辽宁科学技术出版社,2003,255-259. *
白洋等.低温烧结平面六方铁氧体的非线性磁性研究.《电子元件与材料》.2006,(第1期),16-18. *

Also Published As

Publication number Publication date
CN101477151A (en) 2009-07-08

Similar Documents

Publication Publication Date Title
CN102074333A (en) Magnetic core set made of mixed materials, magnetic element and manufacturing method
CN100429855C (en) Power supply wave shape correcting filter
Bartoli et al. High-frequency models of ferrite core inductors
US20230223793A1 (en) Reconfigurable Wireless Power Transmitter for Computer Peripherals
CN101477151B (en) Value quantitative method for inductor in EMI filter
CN103312135B (en) For the reduction ripple in adjustable precision D.C. high-current source and restraint speckle circuit and control method
CN204204589U (en) A kind of high impedance contravariant transformer adopting primary-secondary type loop construction
CN202275686U (en) Common mode inductor, common mode filter and switching mode power supply electromagnetic compatibility circuit
CN203910415U (en) Differential-common-mode inductor and inverter comprising inductor
CN204810143U (en) Anti -electromagnetic interference switching power supply
WO2022020584A1 (en) Area-apportioned wireless power antenna for maximized charging volume
CN104217846B (en) Inductor
CN203522544U (en) Low-noise self-excited push-pull converter
Otsuki et al. SMD inductors based on soft-magnetic powder compacts
CN202334284U (en) Filter circuit of radio frequency power amplifier (PA) power source
CN206921607U (en) Surface metalation is integrally formed SMD inductance
CN204516558U (en) A kind of miniature wire-wound inductor
US11476718B2 (en) Systems for extending wireless power transmission charge volume utilizing repeater antennas
CN211742822U (en) Differential-common mode integrated inductor structure
CN213366303U (en) Flat high-current inductor
He et al. Analysis and Design of EMI Filter Based on Differential Mode Inductor Magnetic Integration
US11404919B2 (en) Modular wireless power transmitters for powering multiple devices
Yin et al. An integrated receiver for inductive power transfer
CN211555645U (en) High-frequency reactor
CN202454374U (en) Anti-electromagnetic interference high frequency inductor

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant