CN202275686U - Common mode inductor, common mode filter and switching mode power supply electromagnetic compatibility circuit - Google Patents

Common mode inductor, common mode filter and switching mode power supply electromagnetic compatibility circuit Download PDF

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Publication number
CN202275686U
CN202275686U CN2011203548594U CN201120354859U CN202275686U CN 202275686 U CN202275686 U CN 202275686U CN 2011203548594 U CN2011203548594 U CN 2011203548594U CN 201120354859 U CN201120354859 U CN 201120354859U CN 202275686 U CN202275686 U CN 202275686U
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common mode
winding
mode inductance
magnetic core
amorphous state
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苟霜
于吉永
李伟平
黄昌宾
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China the Great Wall science and technology group Limited by Share Ltd
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China Great Wall Computer Shenzhen Co Ltd
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Abstract

The utility model is applicable to the electronic field, provides a common mode choke, an electromagnetic compatibility circuit and a switching mode power supply electromagnetic compatibility circuit. The common mode choke comprises an amorphous state magnetic core made of an amorphous state material, a first winding and a second winding. The first winding is wound on an outer wall of the amorphous state magnetic core, a dotted terminal of the first winding is an input end of the common mode choke and connected with a zero line, and a synonym terminal of the first winding is an output end of the common code choke. The second winding and the first winding are wound on an outer wall of the amorphous state magnetic core in the same direction, a dotted terminal of the second winding is the other input end of the common mode choke and connected with a fire line, and a synonym terminal of the second winding is the other output end of the common mode choke. An embodiment of the common mode choke adopts the amorphous state material to manufacture the magnetic core, coils are wound on the outer wall of the amorphous state magnetic core to manufacture a common mode winding, saturation induction density of the common code choke is improved to two times, noise suppression effect is improved, the number of turns of the coils is reduced, temperature stability is improved, and frequency band width is increased.

Description

A kind of common mode inductance, common-mode filter and Switching Power Supply electromagnetism compatible circuit
Technical field
The utility model belongs to electronic applications, relates in particular to a kind of common mode inductance, common-mode filter and Switching Power Supply electromagnetism compatible circuit.
Background technology
Along with switching type power supply increasing application in industry and household electrical appliance, the phase mutual interference between the electrical equipment becomes serious day by day problem, and electromagnetic environment more and more is concerned about by people.Electromagnetic interference has many types, and wherein the common mode disturbances between 10K~30MHz is very important one type, and they are mainly propagated with conduction pattern, and normal operation of safety of instrument caused very big harm, must control.Usually at the additional common-mode filter of input, get into electrical appliance through power line, prevent that simultaneously the common mode disturbances that electrical appliance produces from getting into electrical network to alleviate extraneous common mode disturbances.
Usually adopt the more effectively filtering of common-mode filter filtering common mode disturbances; And its core is common mode inductance, and better, the lower-cost Ferrite Material of the common selected frequency characteristic of magnetic core of present common mode inductance is like nickel Zinc material and MnZn material; But because nickel Zinc material magnetic permeability is low; Therefore can not reach high impedance at low frequency, be applicable to that blanketing frequency is higher than the above noise of 20MHz, though and MnZn material magnetic permeability when low frequency is higher; But decay is too fast when high frequency; Be applicable to and suppress the low-frequency noise of 10kHz, and poor, the saturated magnetic strength of Ferrite Material common mode inductance temperature characterisitic is low, magnetic permeability is low etc., and characteristic has received many restrictions when application, is unfavorable for extensive popularization to 50MHz.
The utility model content
The purpose of the utility model embodiment is to provide a kind of common mode inductance, problem such as be intended to solve that the existing saturated magnetic strength of common mode inductance is low, magnetic permeability is low, temperature characterisitic difference and frequency band are narrow.
The utility model embodiment is achieved in that a kind of common mode inductance, and said common mode inductance comprises:
The amorphous state magnetic core of processing by amorphous material;
First winding, said first winding technique are in said amorphous state magnetic core outer wall, and the end of the same name of said first winding is that said common mode inductance one input is connected with zero line, and the different name end of said first winding is said common mode inductance one output;
Second winding; Said second winding and said first winding are wound in said amorphous state magnetic core outer wall in the same way; The end of the same name of said second winding is that another input of said common mode inductance is connected with live wire, and the different name end of said second winding is another output of said common mode inductance.
Further, said amorphous material is an iron-base nanometer crystal alloy.
Further, said amorphous state magnetic core is a toroidal core.
Further, said amorphous state magnetic core is P type, PQ type, E type, RM type or EP type magnetic core.
Another purpose of the utility model embodiment is to provide a kind of common-mode filter that comprises above-mentioned common mode inductance, and said common-mode filter also comprises:
Capacitor C 1 and capacitor C 2;
One end of said capacitor C 1 is connected with an output of said common mode inductance, the other end ground connection of said capacitor C 1, and an end of said capacitor C 2 is connected with another output of said common mode inductance, the other end ground connection of said capacitor C 2.
Another purpose of the utility model embodiment is to provide a kind of Switching Power Supply electromagnetism compatible circuit that comprises above-mentioned common-mode filter.
The utility model embodiment adopts amorphous material to process magnetic core, and processes the common mode winding at amorphous state magnetic core outer wall winding around, and the saturation induction density of common mode inductance is increased to two times; Strengthened noise suppression effect, reduced coil turn, and this common mode inductance magnetic permeability is high; Temperature stability is good; Frequency characteristic is flexible, bandwidth, and initial permeability is high.
Description of drawings
The circuit structure diagram of the common-mode filter that Fig. 1 provides for the utility model one embodiment;
The EMI curve chart of the common mode inductance actual measurement that Fig. 2 provides for the utility model one embodiment;
The EMI curve chart of the common mode inductance actual measurement that the employing Ferrite Material that Fig. 3 provides for the utility model one embodiment is processed.
Embodiment
For the purpose, technical scheme and the advantage that make the utility model is clearer,, the utility model is further elaborated below in conjunction with accompanying drawing and embodiment.Should be appreciated that specific embodiment described herein only in order to explanation the utility model, and be not used in qualification the utility model.
The utility model embodiment adopts amorphous material to process the amorphous state magnetic core; And process the common mode winding at amorphous state magnetic core outer wall winding around; The saturation induction density of common mode inductance is increased to two times; Strengthen noise suppression effect, reduced coil turn, improved temperature stability and frequency bandwidth.
The common mode inductance that provides as the utility model one embodiment can be applicable in the common-mode filter of any kind, and said common mode inductance comprises:
The amorphous state magnetic core of processing by amorphous material;
First winding, this first winding technique are in amorphous state magnetic core outer wall, and the end of the same name of first winding is that common mode inductance one input is connected with zero line, and the different name end of first winding is common mode inductance one output;
Second winding, this second winding and first winding are wound in amorphous state magnetic core outer wall in the same way, and the end of the same name of second winding is that another input of common mode inductance is connected with live wire, and the different name end of second winding is another output of common mode inductance.
In the utility model embodiment; Common mode inductance is made up of two groups of identical first winding and second windings of the number of turn; Two windings are distributed in relative edge on the magnet ring; The magnetic flux equal and opposite in direction that electric current in first winding and second winding produces, in the opposite direction, these two magnetic fluxs are cancelled out each other and are made magnetic core be in not bias state.
As the utility model one embodiment, this amorphous material can be iron-base nanometer crystal alloy, adopts sub-thread to twine, to reduce cost.
As the utility model one preferred embodiment, the amorphous state magnetic core can adopt toroidal core, to reduce the stray magnetic field of magnetic core; Make the magnetic line of force more concentrated, it is close to increase magnetic, and because toroidal core does not have air gap; The magnetic conductance passband that can further improve common mode inductance is more than 30%; With further minimizing coil turn, reduce turn-to-turn capacitance, and then widening frequency band.
As the utility model one embodiment, the amorphous state magnetic core can also adopt P type, PQ type, E type, RM type or the EP type magnetic core etc. of no air gap, to reduce the coil cost.
In the utility model embodiment, with amorphous state magnetic core outer wall in the same way, identical number of turn ground twines two coils, make short-range order and after long-range unordered amorphous material architectural feature combines electromagnetic induction, form common mode inductance with many excellent specific properties.
Table 1 shows the performance parameter correction data of the common mode inductance of amorphous state magnetic core and ferrite material after testing, and details are as follows:
Table 1
Figure BDA0000093059500000041
Initial permeability is high, shown in the table 1, through testing under downfield (10KHz); The magnetic permeability of nickel Zinc material is less than 20000; The magnetic permeability of MnZn material is about 15000, and the initial permeability of the common mode inductance that iron-base nanometer crystal alloy material (the iron-base nanometer crystal alloy material is a kind of of amorphous material) is processed can reach more than 100,000, is higher than the common mode inductance of Ferrite Material far away; Therefore the common mode inductance of iron-base nanometer crystal alloy material magnetic core has big impedance and inserts loss under downfield; Under equal inductance value, dwindling the volume of iron core, and the weak jamming of minimum leakage current had fabulous inhibitory action, especially in some specific occasion; Cause leakage current like Medical Devices through direct-to-ground capacitance (human body); Form common mode disturbances easily, and equipment itself is very accurate to the data requirement, therefore adopts the iron-base nanometer crystal alloy material common mode inductance of high permeability then to be the optimal case of Switching Power Supply electromagnetism compatible circuit.In addition, the iron-base nanometer crystal alloy material common mode inductance of high permeability can also reduce coil turn, and then reduces distribution parameter such as parasitic capacitance, improve by distributed constant cause at the resonance frequency that inserts on the loss spectra, realize increasing frequency bandwidth.
Loss is little; Shown in the table 1; Is that 25KHz (KHz), magnetic flux density are that 200mT (milli tesla), temperature are under 100 ℃ the situation through test in frequency; The loss of iron-base nanometer crystal alloy material common mode inductance is merely 3W/Kg (watt every kilogram), is about sixth to five/one of Ferrite Material, so can expand frequency range.
Saturation induction density is high; Shown in the table 1, be that 25KHz (KHz), magnetic flux density are that 200mT (milli tesla), temperature are that the saturation induction density Bs of iron-base nanometer crystal alloy material common mode inductance can reach 1.2T under 100 ℃ the situation in frequency through test; Be more than the twice of Ferrite Material; Have excellent anti-saturation property, make in the bigger environment of interference strength (for example high-power frequency conversion motor), can avoid magnetic core to descend because of the saturated inductance value that causes; Strengthen noise suppression effect, expanded range of application.
Temperature stability is good, and shown in the table 1, the Curie temperature of warp test ferrite common mode inductance is generally below 250 ℃; And the magnetic property variation is non-linear, and the Curie temperature of iron-base nanometer crystal alloy material common mode inductance can be up to more than 600 ℃, especially in-50 ℃ to 130 ℃ temperature range; The rate of change of magnetic property is in 10%, even under the situation that big temperature fluctuation is arranged, the performance change rate of nanometer crystal alloy is also far below ferrite; Show extremely stable temperature characterisitic, and, for temperature tolerance; The nickel Zinc material can steady operation under the temperature about 120 ℃, MnZn material can be under the temperature below 100 ℃ steady operation, and amorphous material can be higher than steady operation under 120 ℃ the temperature, therefore; The temperature tolerance of nanometer crystal alloy is better, for designs provides loose temperature conditions.
Frequency characteristic is flexible; Through testing through different manufacturing process; The amorphous state magnetic core of iron-base nanometer crystal alloy material has different frequency characteristics, cooperating the coil that twines the suitable number of turn can obtain the different impedance characteristic, obtains needed frequency characteristic through adjusting process more neatly; Satisfying the filtering requirements of different-waveband, and its resistance value is much higher than the common mode inductance of Ferrite Material.
The utility model embodiment adopts amorphous material to process magnetic core, and processes the common mode winding at amorphous state magnetic core outer wall winding around, and the saturation induction density of common mode inductance is increased to two times; Strengthened noise suppression effect, reduced coil turn, and this common mode inductance magnetic permeability is high; Temperature stability is good; Frequency characteristic is flexible, bandwidth, and initial permeability is high.
Be elaborated below in conjunction with the realization of specific embodiment to the utility model.
Fig. 1 shows the structure of the common-mode filter that the utility model one embodiment provides, and for the ease of explanation, only shows the part relevant with the utility model embodiment.
The common-mode filter that provides as the utility model one embodiment can be applicable in the Switching Power Supply electromagnetism compatible circuit of any structure, and this common-mode filter comprises:
Common mode inductance 1, the input of this common mode inductance is electrically connected with the city;
Capacitor C 1, an end of this capacitor C 1 is connected with an output of common mode inductance 1, the other end ground connection of capacitor C 1;
Capacitor C 2, an end of this capacitor C 2 is connected with another output of common mode inductance 1, the other end ground connection of capacitor C 2.
In the utility model embodiment, the common 10kHz~30MHz of noise spectrum that Switching Power Supply produces is directed to this frequency common mode inductance is designed, and guarantees that inductive impedance is enough high, reaches enough attenuations.
Details are as follows for concrete design:
If frequency f=10kHz, reactance Z S=1000 Ω, the effective value of input current I are 3A, current density j=400A/cm 2, inductance value L S=X S/ 2 π f.
Select conductor size: A Ct=I/j=3/4=0.75mm 2, A wherein CtBe the sectional area of lead, unit is a square millimeter, so selection wire footpath d=1mm, sectional area A Ct=0.785mm 2, the bare wire diameter d 1=1.11mm.
Calculate minimum inductance: L Min = 1000 2 π × 10 4 = 1.59 MH .
In the utility model embodiment, the common mode inductance of processing with the iron-base nanometer crystal alloy material is an example, its inductance coefficent A L=30000 ± 30%, establish inside diameter D=8.65mm ± 0.20mm, minimum interior through D Min=8.45mm, for making two intercoil insulations, each coil occupies 150 °~170 ° of inner peripherys, the preferred 160 ° of winding arounds of this programme (winding).
Calculate the inner periphery and the reelable maximum number of turn: inner periphery D 1=π (D Min-d 1)=π (8.45-1.11)=23.05mm, maximum number of turn N Max=(D 1/ 2 π) * (D 1/ d 1160 °/360 ° of)=() * (23.05/1.11)=9.22 circle is got 9 circles.
Calculating needs the number of turn: N = 1000 L A L = 1000 1.59 30000 × 0.7 = 8.7 Circle, wherein N is the number of turn, and L is an inductance value, and unit is mH, A LBe inductance coefficent.
Therefore, the common mode inductance of processing with the iron-base nanometer crystal alloy material that the utility model embodiment provides can be realized reaching the coil turn that 1000 Ω impedances are twined under the situation that is 8.45mm in minimum fully, and coil turn is few; The copper product consumption is few; Save cost, and the copper loss that produces is little, conversion efficiency is higher; The copper caloric value is low, and temperature rise is low.
Be that example compares its inductance coefficent A below with the Ferrite Material L=60000 ± 30%, establish inside diameter D=13.47mm ± 0.30mm, minimum interior through D Min=13.17mm, each coil occupy 160 ° of inner peripherys.
Calculate the inner periphery and the reelable maximum number of turn: inner periphery D 1=π (D Min-d 1)=π (13.17-1.11)=37.87mm, maximum number of turn N Max=(D 1/ 2 π) * (D 1/ d 1160 °/360 ° of)=() * (37.87/1.11)=15.16 circle is got 15 circles.
And calculating needs the number of turn: N = 1000 L A L = 1000 1.59 60000 × 0.7 = 19.4 Circle, greater than the reelable maximum number of turn 15 circles of this magnetic core, therefore with this understanding, the common mode inductance of Ferrite Material can't reach enough impedances, realizes suppressing fully interference signal.
In the utility model embodiment; Fig. 2 shows the electromagnetic interference (EMI that adopts the common mode inductance actual measurement that amorphous material processes; Electronic Magnetic Interference) curve; Be respectively (the IEC of International Power committee among the figure from top to bottom; International Electrotechnical Commission) the EMI curve of EN55022CLASS-B standard limited value line EN55022Q, EN55022A and the amorphous material common mode inductance actual measurement of processing; Fig. 3 shows the EMI curve that adopts the common mode inductance actual measurement that Ferrite Material processes; Be respectively the EMI curve that is respectively the common mode inductance actual measurement that (IEC, International Electrotechnical Commission) the EN55022 CLASS-B standard limited value line EN55022Q of International Power committee, EN55022A and Ferrite Material process among the figure from top to bottom among the figure from top to bottom.
After the contrast; Can know; The EMI curve of the common mode inductance actual measurement that the EMI curve ratio Ferrite Material of the common mode inductance actual measurement that amorphous material is processed is processed is more far below each item industry standard; Therefore the EMI performance of the common mode inductance processed of amorphous material is superior to the common mode inductance that Ferrite Material is processed, and promptly the interference free performance of the common mode inductance processed of amorphous material is better.
The utility model embodiment adopts amorphous material to process magnetic core, and processes the common mode winding at amorphous state magnetic core outer wall winding around, and the saturation induction density of common mode inductance is increased to two times; Strengthen noise suppression effect, reduced coil turn, reduced the copper resistance; Improved the power supply overall efficiency, saved the cost of manufacture of common mode inductance, this common mode inductance magnetic permeability is high; Temperature stability is good, and frequency characteristic is flexible, bandwidth; Initial permeability is high, and the weak jamming of minimum leakage current is had fabulous inhibitory action.
More than be merely the preferred embodiment of the utility model,, any modification of being done within all spirit at the utility model and the principle, be equal to and replace and improvement etc., all should be included within the protection range of the utility model not in order to restriction the utility model.

Claims (6)

1. a common mode inductance is characterized in that, said common mode inductance comprises:
The amorphous state magnetic core of processing by amorphous material;
First winding, said first winding technique are in said amorphous state magnetic core outer wall, and the end of the same name of said first winding is that said common mode inductance one input is connected with zero line, and the different name end of said first winding is said common mode inductance one output;
Second winding; Said second winding and said first winding are wound in said amorphous state magnetic core outer wall in the same way; The end of the same name of said second winding is that another input of said common mode inductance is connected with live wire, and the different name end of said second winding is another output of said common mode inductance.
2. common mode inductance as claimed in claim 1 is characterized in that, said amorphous material is an iron-base nanometer crystal alloy.
3. common mode inductance as claimed in claim 1 is characterized in that, said amorphous state magnetic core is a toroidal core.
4. common mode inductance as claimed in claim 1 is characterized in that, said amorphous state magnetic core is P type, PQ type, E type, RM type or EP type magnetic core.
5. a common-mode filter is characterized in that, said common-mode filter comprises like each described common mode inductance of claim 1 to 4, also comprises:
Capacitor C 1, an end of said capacitor C 1 is connected with an output of said common mode inductance, the other end ground connection of said capacitor C 1;
Capacitor C 2, an end of said capacitor C 2 is connected with another output of said common mode inductance, the other end ground connection of said capacitor C 2.
6. a Switching Power Supply electromagnetism compatible circuit is characterized in that, said Switching Power Supply electromagnetism compatible circuit comprises common-mode filter as claimed in claim 5.
CN2011203548594U 2011-09-21 2011-09-21 Common mode inductor, common mode filter and switching mode power supply electromagnetic compatibility circuit Expired - Lifetime CN202275686U (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103021628A (en) * 2011-09-21 2013-04-03 中国长城计算机深圳股份有限公司 Common mode choke, common mode filter and switching power supply electromagnetic compatible circuit
CN110022056A (en) * 2019-05-07 2019-07-16 谢群 Common mode noise suppression circuit
CN114586247A (en) * 2019-09-06 2022-06-03 模拟电力转换有限责任公司 Transient noise reduction filtering system

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103021628A (en) * 2011-09-21 2013-04-03 中国长城计算机深圳股份有限公司 Common mode choke, common mode filter and switching power supply electromagnetic compatible circuit
CN103021628B (en) * 2011-09-21 2016-02-10 中国长城计算机深圳股份有限公司 A kind of common mode inductance, common-mode filter and Switching Power Supply electromagnetism compatible circuit
CN110022056A (en) * 2019-05-07 2019-07-16 谢群 Common mode noise suppression circuit
CN114586247A (en) * 2019-09-06 2022-06-03 模拟电力转换有限责任公司 Transient noise reduction filtering system

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Address after: 518057 computer building of the Great Wall, Nanshan District science and Technology Park, Shenzhen, Guangdong

Patentee after: China the Great Wall science and technology group Limited by Share Ltd

Address before: 518057 computer building of the Great Wall, Nanshan District science and Technology Park, Shenzhen, Guangdong

Patentee before: China Changcheng Computer Shenzhen Co., Ltd.

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Granted publication date: 20120613