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WO2016046826A1 - Transformateurs résonnants et leurs applications - Google Patents

Transformateurs résonnants et leurs applications Download PDF

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Publication number
WO2016046826A1
WO2016046826A1 PCT/IL2015/050967 IL2015050967W WO2016046826A1 WO 2016046826 A1 WO2016046826 A1 WO 2016046826A1 IL 2015050967 W IL2015050967 W IL 2015050967W WO 2016046826 A1 WO2016046826 A1 WO 2016046826A1
Authority
WO
WIPO (PCT)
Prior art keywords
converter
voltage
substantially rectangular
voltage signal
transformer
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.)
Ceased
Application number
PCT/IL2015/050967
Other languages
English (en)
Inventor
Alexander JARONKIN
Zeev Shpiro
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.)
Advanced Magnetic Solutions Ltd
Original Assignee
Advanced Magnetic Solutions Ltd
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 Advanced Magnetic Solutions Ltd filed Critical Advanced Magnetic Solutions Ltd
Publication of WO2016046826A1 publication Critical patent/WO2016046826A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F3/00—Cores, Yokes, or armatures
    • H01F3/10—Composite arrangements of magnetic circuits
    • H01F3/14—Constrictions; Gaps, e.g. air-gaps
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F30/00—Fixed transformers not covered by group H01F19/00
    • H01F30/04—Fixed transformers not covered by group H01F19/00 having two or more secondary windings, each supplying a separate load, e.g. for radio set power supplies
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F30/00—Fixed transformers not covered by group H01F19/00
    • H01F30/06—Fixed transformers not covered by group H01F19/00 characterised by the structure
    • H01F30/10—Single-phase transformers
    • 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
    • H02M3/00—Conversion of DC power input into DC power output
    • H02M3/22—Conversion of DC power input into DC power output with intermediate conversion into AC
    • H02M3/24—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
    • H02M3/28—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC
    • H02M3/325—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33569—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
    • H02M3/33576—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
    • 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
    • H02M3/00—Conversion of DC power input into DC power output
    • H02M3/22—Conversion of DC power input into DC power output with intermediate conversion into AC
    • H02M3/24—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
    • H02M3/28—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC
    • H02M3/325—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/337—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only in push-pull configuration
    • H02M3/3376—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only in push-pull configuration with automatic control of output voltage or current
    • 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
    • H02M1/0048—Circuits or arrangements for reducing losses
    • H02M1/0054—Transistor switching losses
    • H02M1/0058—Transistor switching losses by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Definitions

  • the present invention relates generally to resonant transformers and their applications to power supplies, and more particularly, to resonant based switching power supplies.
  • PS Power Adapters
  • the current market specifications for AC to DC switching power supplies include target efficiency of about 90% over a wide range of AC input voltages (90V to 264V) and loading conditions.
  • the demand for smaller size PS intensifies the requirement for high efficiency due to the necessity to dissipate the heat resulting from the PS losses through the small PS package surface area.
  • resonant (e.g. LLC) based PS e.g. DC to DC Converter, AC to DC Converter, etc.
  • the Transformer is a key element of the Power Adapter circuit, affecting its dimensions weight and efficiency. An innovative transformer structure is thus needed for enabling small, light and efficient resonant based Power Adapters.
  • an isolating transformer comprising a primary winding having multiple turns, two secondary windings each consists of at least one turn both having the same number of turns, and a core with an air gap on which the primary and secondary windings are wound.
  • the two secondary windings are disposed symmetrically with respect to the air gap and the winding plane of the two secondary windings and of the air gap have a substantially common axis of symmetry.
  • each of the two secondary windings consists of a single turn.
  • the substantially common axis of symmetry also relates to the winding plane of the primary winding.
  • the air gap is located in the middle of a central leg of the core.
  • a DC to DC converter comprising a switching stage configured to convert a DC input voltage to a substantially rectangular voltage signal, the above transformer operatively coupled to the switching stage for forwarding the substantially rectangular voltage signal in an isolating manner, and an output rectifying circuit coupled to the two secondary windings for producing a DC output voltage.
  • the output rectifying circuit is configured to forward power from each of the two secondary windings during different half cycle of the substantially rectangular voltage signal.
  • the DC to DC converter further includes at least one capacitive element operatively coupled to the primary winding for causing resonance to affect the current flowing through the primary winding while forwarding the substantially rectangular voltage signal.
  • the DC to DC converter operates as an LLC type DC to DC converter.
  • the DC to DC converter further comprising a control arrangement configured to affect the substantially rectangular voltage signal frequency, based on operatively sensing the DC output voltage, so as to maintain the DC output voltage within a predetermined DC voltage range.
  • the control arrangement is configured to affect the frequency of the substantially rectangular voltage signal continuously.
  • the control arrangement is configured to affect the substantially rectangular voltage signal frequency based on operatively sensing both the DC input voltage and the DC output voltage, so as to maintain the DC output voltage within a predetermined DC voltage range .
  • each of the two secondary windings consists of less than 4 turns, the transfer ratio of the transformer is greater than 30, and the control arrangement is configured to determine a desired value of the DC output voltage so as to maintain the DC output voltage within the predetermined DC voltage range while the DC input voltage is variable from a minimum DC input voltage to at least twice the minimum DC input voltage.
  • control arrangement is further configured to detect the amount of loading of the DC output voltage and to cause reduction of the overall capacitance of the at least one capacitive element in response to detecting that the loading of the DC output voltage is, smaller than a predetermined value.
  • the substantially rectangular voltage signal frequency may be maintained above or below F0 - the resonance frequency of the primary current resonance .
  • a AC to DC converter comprising an input rectifying circuit and the above DC to DC converter coupled to the input rectifying circuit.
  • the input rectifying circuit is adapted to receive an AC voltage that is variable in the range of at least 100-240Vac.
  • Fig. 1 is a block diagram that schematically illustrates a DC to DC and an AC to DC converter, in accordance with an embodiment of the present invention.
  • FIGS. 2A and 2B are mechanical diagrams that schematically illustrate transformer configurations, in accordance with embodiments of the present invention,-
  • Embodiments of the present invention that are described below relate to efficient resonant transformers, efficient DC to DC converters, and efficient AC to DC converters that include the above DC to DC converters .
  • the AC to DC converter includes an LLC type DC to DC converter which includes an efficient high transfer ratio isolating transformer.
  • a block diagram 100 that schematically illustrates an AC to DC converter, in accordance with an embodiment of the present invention.
  • Typical flow of electrical power through converter 100 starts with an AC line voltage applied to an input line filter 104.
  • the AC voltage may vary in the range of at least 100V to 240V RMS, while, in an embodiment, a safety margin of +/-10% is supported.
  • Input filter 104 comprises inductive and capacitive elements for suppressing interference from the line as well as switching noise produced by converter 100. There are multiple known ways to implement such filter.
  • rectifying circuit 106 rectifies the AC voltage by means of a diode bridge 112.
  • a storage capacitor 114 then smooths the rectified voltage thus producing a DC voltage associated with some ripple at frequency of twice the line frequency.
  • the resulting DC input voltage, denoted Vin is provided to a DC to DC converter 108 for powering an external load 110 with a regulated DC output voltage denoted Vout.
  • a switching stage 116 converts Vin to a rectangular voltage signal of frequency F by means of fast power switches 118 and 120.
  • MOSFET switches are used, however, in other embodiments other switch types may be used.
  • a coupling capacitor 122 transfers the rectangular voltage signal to an isolating transformer 124.
  • the transformer comprises a primary winding 126 of about 60 turns, and two secondary windings 128 and 130 of a single turn each. Consequently, the transfer ratio Vs/Vp is about 1/60. In other embodiments, other turn numbers and ratios may be implemented and additional secondary windings and associated circuits may be employed. All windings are wound on a core 132. Winding 126 and capacitor 122 constitute a resonant circuit with a resonant frequency F0 of about 50 Hz. In other embodiments, other techniques and schemes and resonance frequencies are employed to construct the resonance circuit.
  • An output rectifying circuit 134 that follows transformer 124 rectifies the transformer output for supplying DC power to external load 110, once connected to converter 100.
  • switch 136 rectifies winding 128 output to charge output capacitor 138
  • switch 140 rectifies winding 130 output to charge output capacitor 142.
  • switches 136 and 140 may be implemented by different components such as diodes and transistors. Switches 136 and 140 are connected to inverse polarities of windings 128 and 130 respectively so that each of the two secondary windings charges its corresponding output capacitor during different half cycle of the rectangular voltage signal. The voltages on capacitors 138 and 142 then sum up, by virtue of their serial interconnection, to produce Vout of about 10V.
  • Control circuit 144 serves for controlling all the aforementioned switches. It comprises a primary part 148 for controlling switches 118 and 120, and a secondary part 146 for controlling switches 136 and 140. Both parts are interconnected by an isolating optical coupling unit 150. In the following description no distinction is made between the two parts of control circuit 144.
  • control circuit 144 comprises a general purpose micro-processor for control and management operations as well as an ASIC for fast control of the switches as well as for driving thereof.
  • Control circuit 144 determines Vout while attempting to maintain it within a predetermined permitted range by continuously determining an appropriate switching rate of switching stage 116, thereby the frequency F of the rectangular voltage signal at its output, which is normally higher than F0. For this sake, control circuit 144 continuously senses Vout as illustrated in Fig. 1. Upon sensing a small reduction of Vout, due to a positive change in the load current and/or a negative change in Vin, it slightly decreases F to bring it closer to F0, thus increasing the gain of the resonant circuit. Correspondingly, an increase in Vout would entail increased F, hence decreased gain of the resonant circuit. When F is close to F0, the resonant gain is high, which allows for low AC input voltage.
  • the resonant gain is low, which allows for high AC input voltage.
  • a wide input voltage range thus necessitates high quality factor (Q) of the resonant circuit, which is achieved by high magnetizing current through primary winding 126.
  • Q quality factor
  • the transformer loss which is normally implied by high magnetizing current, is minimized due to the specific structure of transformer 124, as described below.
  • control circuit 144 senses also Vin so as to improve the dynamics of the above described control loop.
  • circuit 152 is included in converter 108, comprising a capacitor 156 which is switchable by a switch 154.
  • control circuit 144 detects, typically based on Vin and F, that the load current is quite low, e.g. below half of its rated value, it sets switc 154 off, thereby decreasing the overall capacitance in series with winding 126. This increases the resonant impedance (Zo) of the resonant circuit, thereby decreases the magnetizing current and thus the loss in the converter.
  • Zo resonant impedance
  • F is not changed meaningfully respectively and becomes lower than FO .
  • Fig. 2A is a mechanical diagram, presented in a crosssectional view, that schematically illustrates transformer 116 configuration, in accordance with an embodiment of the present invention.
  • the transformer includes magnetic core 132 having an air gap 204 in the middle of a central leg 210 of the core.
  • core 132 is an EQ structured soft ferrite made of MnZn. In other embodiments other core structures and materials can be employed.
  • Primary winding 126 is disposed in a single section bobbin 208. On both sides of the bobbin there are secondary windings 128 and 130, each consisting of a single turn.
  • the secondary windings are of Helical Coil inding type.
  • a dashed line 212 depicts the axis of symmetry of air gape 204, i.e. it is perpendicular to the air gap plane and crosses its center.
  • transformer 124 There are two symmetry related properties of transformer 124 that are manifested in Fig. 2A:
  • Secondary windings 128 and 130 are identical, and disposed symmetrically with respect to air gap 204.
  • the winding plane of primary winding 126 has the same axis of symmetry as air gap 204.
  • Fig. 2B shows a mechanical diagram, presented in a crosssectional view, that schematically illustrates transformer 116 configuration, in accordance with an alternative embodiment of the present invention.
  • Fig. 2B differs from Fig. 2A in that secondary windings 128a and 130a are wound over primary winding 126 and are separated therefrom by an isolation tape 216.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Dc-Dc Converters (AREA)

Abstract

L'invention concerne un transformateur d'isolement qui comprend un enroulement primaire comportant de multiples spires, deux enroulements secondaires constitués chacun d'au moins une spire, chaque enroulement comprenant le même nombre de spires, et un noyau comprenant un entrefer sur lequel les enroulements primaire et secondaires sont enroulés. Les deux enroulements secondaires sont disposés symétriquement par rapport à l'entrefer, et les plans d'enroulement des deux enroulements secondaires et de l'entrefer ont un axe de symétrie sensiblement commun. L'invention concerne également des convertisseurs CC-CC et CA-CC qui comprennent le transformateur susmentionné.
PCT/IL2015/050967 2014-09-23 2015-09-22 Transformateurs résonnants et leurs applications Ceased WO2016046826A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201462053841P 2014-09-23 2014-09-23
US62/053,841 2014-09-23

Publications (1)

Publication Number Publication Date
WO2016046826A1 true WO2016046826A1 (fr) 2016-03-31

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Family Applications (1)

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PCT/IL2015/050967 Ceased WO2016046826A1 (fr) 2014-09-23 2015-09-22 Transformateurs résonnants et leurs applications

Country Status (1)

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WO (1) WO2016046826A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111095758A (zh) * 2017-12-11 2020-05-01 株式会社日立制作所 电力转换器单元和电力转换装置
CN111865093A (zh) * 2019-09-20 2020-10-30 广州金升阳科技有限公司 开关变换器及其变换方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5539630A (en) * 1993-11-15 1996-07-23 California Institute Of Technology Soft-switching converter DC-to-DC isolated with voltage bidirectional switches on the secondary side of an isolation transformer
US5555494A (en) * 1993-09-13 1996-09-10 Morris; George Q. Magnetically integrated full wave DC to DC converter
WO2001061677A1 (fr) * 2000-02-16 2001-08-23 Ifire Technology Inc. Circuit de commande pour ecran electroluminescent, a commutation, a circuit resonant, a faible consommation d'energie
CN201829308U (zh) * 2010-08-02 2011-05-11 程品电子科技(东莞)有限公司 变压器结构
US20120313433A1 (en) * 2010-03-16 2012-12-13 Murata Manufacturing Co., Ltd. Switching power supply apparatus
WO2014103105A1 (fr) * 2012-12-28 2014-07-03 パナソニック株式会社 Convertisseur cc/cc

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5555494A (en) * 1993-09-13 1996-09-10 Morris; George Q. Magnetically integrated full wave DC to DC converter
US5539630A (en) * 1993-11-15 1996-07-23 California Institute Of Technology Soft-switching converter DC-to-DC isolated with voltage bidirectional switches on the secondary side of an isolation transformer
WO2001061677A1 (fr) * 2000-02-16 2001-08-23 Ifire Technology Inc. Circuit de commande pour ecran electroluminescent, a commutation, a circuit resonant, a faible consommation d'energie
US20120313433A1 (en) * 2010-03-16 2012-12-13 Murata Manufacturing Co., Ltd. Switching power supply apparatus
CN201829308U (zh) * 2010-08-02 2011-05-11 程品电子科技(东莞)有限公司 变压器结构
WO2014103105A1 (fr) * 2012-12-28 2014-07-03 パナソニック株式会社 Convertisseur cc/cc

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111095758A (zh) * 2017-12-11 2020-05-01 株式会社日立制作所 电力转换器单元和电力转换装置
CN111095758B (zh) * 2017-12-11 2023-06-16 株式会社日立制作所 电力转换器单元和电力转换装置
CN111865093A (zh) * 2019-09-20 2020-10-30 广州金升阳科技有限公司 开关变换器及其变换方法
CN111865093B (zh) * 2019-09-20 2022-05-20 广州金升阳科技有限公司 开关变换器及其变换方法

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