CN110299833B - Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter - Google Patents

Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter Download PDF

Info

Publication number
CN110299833B
CN110299833B CN201910602772.5A CN201910602772A CN110299833B CN 110299833 B CN110299833 B CN 110299833B CN 201910602772 A CN201910602772 A CN 201910602772A CN 110299833 B CN110299833 B CN 110299833B
Authority
CN
China
Prior art keywords
common
buck converter
windings
mode
mode voltage
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
CN201910602772.5A
Other languages
Chinese (zh)
Other versions
CN110299833A (en
Inventor
谢立宏
阮新波
朱昊楠
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.)
Nanjing University of Aeronautics and Astronautics
Original Assignee
Nanjing University of Aeronautics and Astronautics
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 Nanjing University of Aeronautics and Astronautics filed Critical Nanjing University of Aeronautics and Astronautics
Priority to CN201910602772.5A priority Critical patent/CN110299833B/en
Publication of CN110299833A publication Critical patent/CN110299833A/en
Application granted granted Critical
Publication of CN110299833B publication Critical patent/CN110299833B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/44—Circuits or arrangements for compensating for electromagnetic interference in converters or inverters

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)

Abstract

The invention discloses a common mode voltage cancellation method and a circuit for inhibiting common mode conducted interference of a Buck converter, wherein the cancellation method comprises the following steps: common-mode conducted interference of the Buck converter is suppressed by offsetting the common-mode voltage of the Buck converter; the common-mode voltage of the Buck converter is obtained by adding two windings to an input power line; the two windings are coupled to an output filter inductor winding. The invention provides a common mode voltage cancellation method for realizing the suppression of common mode conduction, and common mode conduction interference of a Buck converter is suppressed by canceling the common mode voltage of the Buck converter; according to the invention, the common-mode voltage of the Buck converter is counteracted by adding two windings on the input power line and coupling the windings with the output filter inductance winding; the invention is simple to realize, and does not need to increase the compensation capacitor, thereby avoiding the consistency problem caused by the tolerance introduction of the compensation capacitor, and having higher practicability.

Description

Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter
Technical Field
The invention belongs to the technical field of Buck converter common-mode conducted interference suppression, and particularly relates to a common-mode voltage cancellation method and circuit for suppressing Buck converter common-mode conducted interference.
Background
Since the power device operates in a high frequency switching state, there are nodes in the power electronic converter where the potential changes at a high frequency. The high-frequency changing potential can generate displacement current in parasitic capacitance between the nodes and the protection ground, so that Common Mode (CM) conducted interference is caused and enters a power grid through an input power line, and the normal operation of other equipment in the same power grid is influenced.
In order to suppress common mode conducted interference of the converter, a common mode filter composed of a common mode inductor and a Y capacitor is generally added between the input power supply and the converter. Since the Y capacitor is connected between the input power line and the protection ground, the capacitance value is limited by the leakage current and is limited to an upper limit value. Thus, the common mode inductance tends to be large in order to achieve the desired attenuation requirements. In addition, the windings of the common mode inductor pass the input current. Therefore, the size and weight of the common mode inductor are large, and the improvement of the power efficiency and the power density is limited.
Common methods for suppressing interference include a common-mode current cancellation method and a common-mode voltage cancellation method.
Referring to fig. 1, a common mode current cancellation method, in which a 25 Ω resistor is a common mode interference equivalent test impedance, CsumAnd vENSRespectively, the total parasitic capacitance and the equivalent interference source in the common-mode interference model of the converter. Added offset branch route compensation voltage source vcomAnd a compensation capacitor CcomIs formed when the current i flowing through the compensating branchcomAnd the common mode current i generated by the converternWhen the size equals, the current that flows through the LISN equivalent test impedance is zero, and the common mode conducted interference is restrained, and the compensation voltage and the compensation capacitor meet the following requirements:
Figure GDA0002706223530000011
in fig. 1, the common-mode current generated by the converter is cancelled by the added parallel cancellation branch, however, there is a tolerance in the compensation capacitance, which affects the effect of common-mode interference cancellation.
Referring to FIG. 2, for the common mode voltage cancellation method, a compensation voltage source v is connected in series in the loopcomWhen v iscom＝vENSThe voltage across the 25 omega equivalent test impedance is zero, thereby eliminating common mode interference. The method directly cancels the common-mode voltage of the converter, so the method is called a common-mode voltage cancellation method. The method does not need to compensate the capacitor, and avoids the consistency problem caused by the capacitance tolerance.
According to fig. 2, an equivalent interference source v is establishedENSEqual offset voltage source vcomIs the key to realize common mode interference cancellation. In Buck converters, the equivalent interference source vENSCan be expressed in the form of:
vENS＝kvQ (2)
where k is the ratio of the corresponding parasitic capacitances in the circuit (0)<k<1)，vQThe voltage at the switch node to power ground, i.e., the drain-source voltage of the down tube. Due to vQWith output filter inductor windingVoltage vLfHaving the same alternating current component, i.e.
vQ＝vLf (3)
Condition v for common mode interference cancellation in FIG. 1(b)com＝vENSCombining formula (2) and formula (3) to obtain
vcom＝kvLf (4)
From the equation (4), the required compensation voltage vcomIs compared with the ratio k of the corresponding parasitic capacitance in the circuit and the voltage v across the inductorLfIt is related. Accordingly, an auxiliary winding with a suitable number of turns can be wound on the inductor in a magnetic coupling manner, and the auxiliary winding provides the required compensation voltage, as shown in fig. 3.
According to fig. 3, to obtain the required compensation voltage, the compensation voltage kv should be applied to both input power lines of the converterLfThe common-mode voltage from the LISN test end to the input side of the converter power supply is kvLf。
Disclosure of Invention
The present invention provides a common-mode voltage cancellation method and circuit for suppressing common-mode conducted interference of a Buck converter, which aims to solve the technical problem of the prior art.
In order to achieve the technical purpose, the technical scheme adopted by the invention is as follows:
a common-mode voltage cancellation method for suppressing common-mode conducted interference of a Buck converter is provided, and the cancellation method comprises the following steps: common-mode conducted interference of the Buck converter is suppressed by offsetting the common-mode voltage of the Buck converter;
the common-mode voltage of the Buck converter is obtained by adding two windings to an input power line;
the two windings are coupled to an output filter inductor winding.
Preferably, one of the two windings is connected with the positive pole of the input power supply and the positive pole of the input of the Buck converter circuit, and the other winding is connected with the negative pole of the input power supply and the negative pole of the input of the Buck converter circuit.
Preferably, the relationship between the two windings and the homonymous terminals of the output filter inductor winding is as follows: the end points connected with the positive electrode and the negative electrode of the input power supply respectively and the end points connected with the switch node in the output filter inductance winding are homonymous ends.
Preferably, the number of turns of the two windings is equal, and the number of turns of the two windings is determined by the ratio of the number of turns of the output filter inductance winding to the parasitic capacitance to the ground in the Buck converter circuit.
A common-mode voltage cancellation circuit for suppressing common-mode conducted interference of a Buck converter comprises the Buck converter circuit and two windings; the two windings are arranged on an input power line of the Buck converter circuit and coupled with an output filter inductance winding of the Buck converter circuit.
Preferably, one of the two windings is connected with the positive pole of the input power supply and the positive pole of the input of the Buck converter circuit, and the other winding is connected with the negative pole of the input power supply and the negative pole of the input of the Buck converter circuit.
Preferably, the relationship between the two windings and the homonymous terminals of the output filter inductor winding is as follows: the end points connected with the positive electrode and the negative electrode of the input power supply respectively and the end points connected with the switch node in the output filter inductance winding are homonymous ends.
Preferably, the number of turns of the two windings is equal, and the number of turns of the two windings is determined by the ratio of the number of turns of the output filter inductance winding to the parasitic capacitance to the ground in the Buck converter circuit.
The invention has the following beneficial effects:
the invention provides a common mode voltage cancellation method for realizing the suppression of common mode conduction, and common mode conduction interference of a Buck converter is suppressed by canceling the common mode voltage of the Buck converter;
according to the invention, the common-mode voltage of the Buck converter is counteracted by adding two windings on the input power line and coupling the windings with the output filter inductance winding;
the invention is simple to realize, and does not need to increase the compensation capacitor, thereby avoiding the consistency problem caused by the tolerance introduction of the compensation capacitor, and having higher practicability.
Drawings
Fig. 1 is a schematic circuit diagram of a common mode current cancellation method.
Fig. 2 is a schematic circuit diagram of a common mode voltage cancellation method.
Fig. 3 is a schematic diagram of an implementation of a common mode voltage cancellation method.
Fig. 4 is a schematic diagram of an implementation of the common-mode voltage cancellation method for suppressing common-mode conducted interference of the Buck converter according to the invention.
Fig. 5 is a circuit schematic diagram of a common-mode voltage cancellation circuit for suppressing common-mode conducted interference of the Buck converter according to the present invention.
Fig. 6 is a circuit diagram of the Buck converter.
Fig. 7 is a circuit diagram of a common mode interference model of the Buck converter.
Fig. 8 is a thevenin equivalent circuit diagram of the Buck converter.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
The invention discloses a common-mode voltage cancellation method for inhibiting common-mode conducted interference of a Buck converter, which comprises the following steps: common-mode conducted interference of the Buck converter is suppressed by offsetting the common-mode voltage of the Buck converter;
the common-mode voltage of the Buck converter is obtained by adding two windings to an input power line;
the two windings are coupled to an output filter inductor winding.
In an embodiment, one of the two windings is connected with the positive pole of the input power supply and the positive pole of the input of the Buck converter circuit, and the other winding is connected with the negative pole of the input power supply and the negative pole of the input of the Buck converter circuit.
In an embodiment, the relationship between the two windings and the homonymous terminals of the output filter inductor winding is as shown in fig. 5: the end points A and C connected with the positive electrode and the negative electrode of the input power supply respectively, and the end point M connected with the switch node in the output filter inductance winding are homonymous ends.
In an embodiment, the number of turns N of said two windingsABAnd NCDEqual and the number of turns of the two windings is determined by the number of turns of the output filter inductor winding NLfAnd the ratio of the parasitic capacitance to the safe ground in the Buck converter circuit. As shown in FIG. 5, NABAnd NCDThe specific expression of (A) is as follows:
Figure GDA0002706223530000041
the invention discloses a common-mode voltage cancellation circuit for inhibiting common-mode conducted interference of a Buck converter, which comprises a Buck converter circuit and two windings; the two windings are arranged on an input power line of the Buck converter circuit and coupled with an output filter inductance winding of the Buck converter circuit.
In an embodiment, one of the two windings is connected with the positive pole of the input power supply and the positive pole of the input of the Buck converter circuit, and the other winding is connected with the negative pole of the input power supply and the negative pole of the input of the Buck converter circuit.
In an embodiment, the relationship between the two windings and the homonymous terminals of the output filter inductor winding is as follows: the end points connected with the positive electrode and the negative electrode of the input power supply respectively and the end points connected with the switch node in the output filter inductance winding are homonymous ends.
In an embodiment, the number of turns of the two windings is equal, and the number of turns of the two windings is determined by the ratio of the number of turns of the output filter inductance winding to the parasitic capacitance to the safe ground in the Buck converter circuit.
The working principle of the invention is as follows: referring to fig. 4, the common mode inductor winding AB and the common mode inductor winding CD, the number of turns N thereofABAnd NCDAre all kNPQIn which N isPQThe number of turns of the filter inductor winding. If the leakage inductance of the winding is neglected, v isBD＝Vin+vAB-vCD＝VinTherefore, the normal operation of the converter is not influenced by adding the common-mode inductance winding. In addition, in order to reduce copper loss of the common mode inductance winding, the input filter capacitor C of the converterinShould be placed between the transformer and the common mode inductor winding so that the current flowing through the common mode inductor winding is direct current.
From the above analysis, the graph5, a circuit diagram of the Buck converter adopting common mode voltage cancellation is given, and the numbers of turns of the common mode inductance windings AB and CD are kNLfIn which N isLfThe number of turns of the filter inductor winding.
The following specific derivation is about the equivalent interference source v of the common-mode conducted interference of the Buck converterENSAnd a capacitor CsumAnd determining the number of turns of the common mode inductor winding based thereon.
FIG. 6 shows a circuit diagram of a Buck converter, where CD1Is the parasitic capacitance of the switch node M to the protection ground; cS1、CS2And CS3Respectively, the output voltage positive pole, the power ground and the parasitic capacitance from the drain of the switching tube Q to the protective ground. And applying an alternative theorem to derive a common-mode interference model of the Buck converter. In Buck converter, the potential of switch node M is high-frequency jump, and its common-mode interference is mainly formed from CD1And (4) causing. For this purpose, the freewheeling diode D is first of all designedfAnd is replaced by an alternating voltage source with a waveform consistent with the voltage waveform at two ends of the alternating voltage source. Due to dvo/dt<<dvDfAnd/dt, the output capacitance can therefore be considered as a short circuit. In order to avoid a pure voltage source loop in the circuit, a switching tube Q and a filter inductor L are connectedfRespectively, are replaced by alternating current sources in accordance with the waveform of the current flowing therethrough. Finally, a common-mode interference model of the Buck converter can be obtained by considering 25 Ω equivalent test impedance of the common-mode interference at the LISN side, as shown in fig. 7.
The right-end network of the 25 Ω resistor in the model is simplified by the superposition theorem: the voltage source v is driven by considering only the action of the current sourceDfShort-circuited, then current source iQAnd iLfShort-circuited, without influence on common mode interference; considering only the effect of the voltage source, the current source iQAnd iLfOpen circuit, then subject this sub-circuit to thevenin equivalence, resulting in a circuit as shown in fig. 8. Wherein
Figure GDA0002706223530000051
Csum＝CD1+CS1+CS2 (5b)
As can be seen from FIG. 6, since v isDfAnd the filter inductance voltage vLfIs the same, so that the expression for the equivalent interference source can be written as kbuckvLf. Thus, as shown in fig. 4, the common mode inductor windings AB and CD are coupled to the output filter inductor winding with k winding turnsbuckNLf。
The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention.

Claims (6)

1. A common-mode voltage cancellation method for suppressing common-mode conducted interference of a Buck converter is characterized by comprising the following steps: the cancellation method comprises the following steps: common-mode conducted interference of the Buck converter is suppressed by offsetting the common-mode voltage of the Buck converter;
the common-mode voltage of the Buck converter is obtained by adding two windings to an input power line;
the two windings are coupled with the output filter inductance winding;
one winding of the two windings is connected with the positive pole of the input power supply and the positive pole of the input of the Buck converter circuit, and the other winding is connected with the negative pole of the input power supply and the negative pole of the input of the Buck converter circuit.
2. The common-mode voltage cancellation method for suppressing the common-mode conducted interference of the Buck converter according to claim 1, wherein: the homonymous end relation between the two windings and the output filter inductance winding is as follows: the end points connected with the positive electrode and the negative electrode of the input power supply respectively and the end points connected with the switch node in the output filter inductance winding are homonymous ends.
3. The common-mode voltage cancellation method for suppressing the common-mode conducted interference of the Buck converter according to claim 1, wherein: the number of turns of the two windings is equal, and the number of turns of the two windings is determined by the ratio of the number of turns of the output filter inductance winding to the parasitic capacitance to the safety ground in the Buck converter circuit.
4. A common mode voltage cancellation circuit for suppressing common mode conducted interference of a Buck converter is characterized in that: the Buck converter comprises a Buck converter circuit and two windings; the two windings are arranged on an input power line of the Buck converter circuit and coupled with an output filter inductance winding of the Buck converter circuit;
one winding of the two windings is connected with the positive pole of the input power supply and the positive pole of the input of the Buck converter circuit, and the other winding is connected with the negative pole of the input power supply and the negative pole of the input of the Buck converter circuit.
5. The common-mode voltage cancellation circuit for suppressing the common-mode conducted interference of the Buck converter according to claim 4, wherein: the homonymous end relation between the two windings and the output filter inductance winding is as follows: the end points connected with the positive electrode and the negative electrode of the input power supply respectively and the end points connected with the switch node in the output filter inductance winding are homonymous ends.
6. The common-mode voltage cancellation circuit for suppressing the common-mode conducted interference of the Buck converter according to claim 4, wherein: the number of turns of the two windings is equal, and the number of turns of the two windings is determined by the ratio of the number of turns of the output filter inductance winding to the parasitic capacitance to the safety ground in the Buck converter circuit.
CN201910602772.5A 2019-07-05 2019-07-05 Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter Active CN110299833B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910602772.5A CN110299833B (en) 2019-07-05 2019-07-05 Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910602772.5A CN110299833B (en) 2019-07-05 2019-07-05 Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter

Publications (2)

Publication Number Publication Date
CN110299833A CN110299833A (en) 2019-10-01
CN110299833B true CN110299833B (en) 2020-11-24

Family

ID=68030471

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910602772.5A Active CN110299833B (en) 2019-07-05 2019-07-05 Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter

Country Status (1)

Country Link
CN (1) CN110299833B (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6507176B2 (en) * 2001-03-02 2003-01-14 Technical Witts, Inc. Synthesis methods for enhancing electromagnetic compatibility and AC performance of power conversion circuits
US6822427B2 (en) * 2002-05-01 2004-11-23 Technical Witts, Inc. Circuits and circuit elements for high efficiency power conversion
CN1324797C (en) * 2003-05-20 2007-07-04 台达电子工业股份有限公司 Isolated voltage regulator with one core structure
CN101159411A (en) * 2005-07-26 2008-04-09 国际整流器公司 Multi-phase buck converter with a plurality of coupled inductors
WO2010004971A1 (en) * 2008-07-08 2010-01-14 カルソニックカンセイ株式会社 Motor drive device
CN105191102A (en) * 2013-02-25 2015-12-23 西北大学 A switched mode drive circuit

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104183373A (en) * 2013-05-24 2014-12-03 台达电子工业股份有限公司 Transformer
CN206908529U (en) * 2017-05-19 2018-01-19 丰郅(上海)新能源科技有限公司 The inversion system and inverter circuit, polyphase inverter of suppression common mode interference

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6507176B2 (en) * 2001-03-02 2003-01-14 Technical Witts, Inc. Synthesis methods for enhancing electromagnetic compatibility and AC performance of power conversion circuits
US6822427B2 (en) * 2002-05-01 2004-11-23 Technical Witts, Inc. Circuits and circuit elements for high efficiency power conversion
CN1324797C (en) * 2003-05-20 2007-07-04 台达电子工业股份有限公司 Isolated voltage regulator with one core structure
CN101159411A (en) * 2005-07-26 2008-04-09 国际整流器公司 Multi-phase buck converter with a plurality of coupled inductors
WO2010004971A1 (en) * 2008-07-08 2010-01-14 カルソニックカンセイ株式会社 Motor drive device
CN105191102A (en) * 2013-02-25 2015-12-23 西北大学 A switched mode drive circuit

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"Analysis and experimentation with passive cancellation of common-mode noise in buck converter";K.Seshu Babu,等;《2006 9th International Conference on Electromagnetic Interference and Compatibility(INCEMIC 2006)》;20100225;全文 *

Also Published As

Publication number Publication date
CN110299833A (en) 2019-10-01

Similar Documents

Publication Publication Date Title
US8670250B2 (en) Common mode noise reduction apparatus and method
WO2019091393A1 (en) Planar transformer, power source switching circuit and adapter
US20130049918A1 (en) Common Mode Choke Apparatus and Method
JP5634102B2 (en) Grid interconnection inverter
WO2016027374A1 (en) Power conversion device
CN105099205B (en) Switching Power Supply, inverse excitation type converter and transformer
CN110289752B (en) Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of LLC resonant converter
Chan et al. Common-mode noise cancellation in switching-mode power supplies using an equipotential transformer modeling technique
CN103065773B (en) The switching mode power supply transformer of low noise and low noise Switching Power Supply
Naayagi Electromagnetic compatibility issues of dual active bridge DC-DC converter
CN103700484A (en) Method for designing auxiliary winding of switching power supply high-frequency transformer to inhibit common-mode electromagnetic interference (EMI)
Khalid et al. Bidirectional modular Dual Active Bridge (DAB) converter using multi-limb-core transformer with symmetrical LC series resonant tank based on cascaded converters in solid state transformer (SST)
Nan et al. A common mode and differential mode integrated EMI filter
CN110299833B (en) Common-mode voltage cancellation method and circuit for inhibiting common-mode conducted interference of Buck converter
CN217115920U (en) 100W four-way low EMI flyback switching power supply and circuit thereof
Asadi et al. Using magnetizing reactances of transformer in hybrid active power filter
CN210075073U (en) Direct-current power supply filter without generating large starting current
CN103036237A (en) Static synchronous compensator (STATCOM) capable of suppressing delta-type connection internal circulation
Han et al. Suppressing methods of common-mode noise in LLC resonant DC-DC converters
CN204304786U (en) A kind of switch power supply line structure
Pawaskar et al. Harmonic filter with low coupling capacitance for Medium Voltage, high dv/dt PWM converters
CN111464009B (en) Common-mode voltage cancellation method and device suitable for phase-shift control full-bridge converter
Cobb Mitigation of common mode noise for PFC Boost Converter by balancing technique
WO2022088728A1 (en) Planar transformer, power source conversion circuit, and adapter
He et al. Analysis and Design of EMI Filter Based on Differential Mode Inductor Magnetic Integration

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant