EP3961660A1 - Composant inductif pour un onduleur et onduleur - Google Patents

Composant inductif pour un onduleur et onduleur Download PDF

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Publication number
EP3961660A1
EP3961660A1 EP20193287.8A EP20193287A EP3961660A1 EP 3961660 A1 EP3961660 A1 EP 3961660A1 EP 20193287 A EP20193287 A EP 20193287A EP 3961660 A1 EP3961660 A1 EP 3961660A1
Authority
EP
European Patent Office
Prior art keywords
inductance
core
inductive component
component according
core material
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.)
Withdrawn
Application number
EP20193287.8A
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German (de)
English (en)
Inventor
Henrik Krupp
Michael Kopf
Markus Pfeifer
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.)
Siemens AG
Original Assignee
Siemens AG
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 Siemens AG filed Critical Siemens AG
Priority to EP20193287.8A priority Critical patent/EP3961660A1/fr
Priority to PCT/EP2021/068441 priority patent/WO2022042913A1/fr
Publication of EP3961660A1 publication Critical patent/EP3961660A1/fr
Withdrawn legal-status Critical Current

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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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F17/00—Fixed inductances of the signal type 
    • H01F17/04—Fixed inductances of the signal type  with magnetic core
    • H01F17/06—Fixed inductances of the signal type  with magnetic core with core substantially closed in itself, e.g. toroid
    • H01F17/062—Toroidal core with turns of coil around it
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F3/00—Cores, Yokes, or armatures
    • H01F3/08—Cores, Yokes, or armatures made from powder
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/02—Adaptations of transformers or inductances for specific applications or functions for non-linear operation
    • H01F38/023—Adaptations of transformers or inductances for specific applications or functions for non-linear operation of inductances
    • 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
    • H01F2003/106—Magnetic circuits using combinations of different magnetic materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/02—Adaptations of transformers or inductances for specific applications or functions for non-linear operation
    • H01F38/023—Adaptations of transformers or inductances for specific applications or functions for non-linear operation of inductances
    • H01F2038/026—Adaptations of transformers or inductances for specific applications or functions for non-linear operation of inductances non-linear inductive arrangements for converters, e.g. with additional windings

Definitions

  • inductances are often used that are magnetically designed in such a way that they either have an almost constant inductance up to the maximum permissible load current or one already at show a steady decrease in inductance that begins with a lower load current.
  • the magnetic core of the coil is made, for example, from an electrical steel sheet or a ferrite, which have a flat permeability profile up to the saturation limit.
  • metal-powder composite materials are predominantly used.
  • the standard electrical sheets described are not well suited as core material for inductor coils.
  • the ratio between the current in the S1 continuous operating state and the respective special load operating state, for example S6 operation is approx. 1:2 to 1:5 Overload operation, for example S6, only a smaller inductance value is sufficient. It is advantageous, in particular for control engineering reasons and for EMC reasons, if this transition takes place evenly, i.e. as linearly as possible.
  • the object of the invention is to provide an inductive component for an inverter and an inverter which can always provide sufficient commutation inductance at high switching frequencies, even in the overload range.
  • Claim 1 comprises an inductive component, for example a choke coil for an inverter with a first partial magnetic core made from a first core material and with a second partial magnetic core made from a second core material.
  • a partial core can consist of one solid piece or composed of several segments of identical material.
  • the second core material differs from the first core material in particular in its magnetic properties.
  • the first partial core and the second partial core form a magnetic core, also referred to below as a core assembly, which is surrounded by at least one circumferential winding of an electrical conductor. This also includes multi-phase coils, which are encircled by a plurality of separate electrical conductors.
  • the core assembly can also have three or more sub-cores, which in turn comprise magnetic materials that differ in their magnetic properties from the first and second core materials.
  • the described inductive component according to patent claim 1 has the advantage that due to the different magnetic properties of the individual sub-cores, they can react differently in changing their inductance when the current strength through the electrical conductor changes.
  • the core material can thus be selected during construction in such a way that, if there is a significant change in the current flowing through the winding, the second core, for example, has a corrective effect on the desired course of the inductance.
  • the combination of the partial cores is selected in such a way that the inductance-current curve runs in such a way that a declining range occurs in which the inductance increases with the Current, starting from a maximum inductance and assumes a minimum inductance value at a maximum permissible current for the component, which is at least 30% of the maximum inductance.
  • the minimum inductance is preferably in a range of 40% and 70% of the maximum inductance.
  • the maximum inductance L max is present at a current that is designed for continuous operation of the component.
  • the continuous operating state also referred to as S1 according to the nomenclature of the nominal operating modes, is the operating state in which an electrical machine can be operated in continuous operation without being damaged.
  • This continuous operating state is defined according to the international standard IEC60034-1 and the European standard EN60034-1.
  • the inductive component described is usually part of a higher-level device, for example the inverter already described.
  • the permissible continuous operating state means the continuous operating state of the superordinate device, ie the inverter, which is therefore also the continuous operating state of the inductive component.
  • the minimum inductance L min is present at the maximum current I max permissible for the component and for the superordinate device according to the standards mentioned above.
  • the declining range has a linearity that deviates from the linear interpolation between the maximum inductance and the minimum inductance by no more than 30%.
  • a curve according to these criteria is equally advantageous for the stability of the converter control, the EMC behavior and the economic possibilities of realizing the inductance.
  • the linearity of the declining range is particularly preferably even more intense and it deviates from the linear interpolation between the maximum inductance and the minimum inductance by no more than 20% and very preferably no more than 10%.
  • the inductance-current profile runs in such a way that a horizontal area occurs in which the inductance runs essentially constant with increasing current intensity.
  • the horizontal range of the inductance runs up to a certain current (for example and preferably the peak current in S1 operation), the inductance in the horizontal range having little or no current dependence.
  • the horizontal range can be very narrow and already transition to the declining range at a current close to 0 amperes.
  • the maximum inductance is at the transition between the horizontal area and the degressive area. Above this current, there is a drop in the inductance of the exciting current, which preferably decreases linearly up to at least one current value, preferably the peak current of the highest permissible operating mode (degressive range).
  • a third partial core which is also designed in such a way that its core material differs from the core material of the first and second core .
  • the third partial core it is possible to increase the current intensity even further, with the minimum inductance and the desired course being ensured by the third partial core.
  • the first core material is an electrical steel sheet or comprises a ferrite.
  • These are common materials for core materials, which have corresponding inductive properties under continuous load operation at conventional frequencies. It is also expedient to use an iron powder for the second core material
  • first and the second partial core are designed as ring cores or E-cores, since the partial cores can be optimally combined magnetically with this geometric design.
  • first and the second ring, and possibly also the third ring are designed to be geometrically congruent.
  • first sub-core and the second sub-core can be placed in parallel and surrounded by the winding.
  • a further embodiment of the invention consists in an inverter which comprises an inductive component according to one of the preceding claims.
  • An inverter configured in this way has the same advantageous properties that are determined by the inductive component and that have already been discussed in this regard.
  • Such an inverter is preferably designed in such a way that it is suitable for switching frequencies above 30 kHz. This also applies to inverters that contain semiconductor switches that are based on so-called wide band gap semiconductors, for example silicon carbide or gallium nitride.
  • FIG. 1 - 3 shows the assembly of an inductive component 2 in the form of a choke coil for an inverter.
  • two ring-shaped part-cores, a first magnetic part-core 4 and a second magnetic part-core 8 are placed one on top of the other.
  • These two sub-cores 4, 8 basically represent the simplest form of the inductive component described.
  • Both cores 4, 8 each have a core material 6, 10, which both differ from one another in terms of their magnetic properties.
  • a third ring 16 and a fourth ring 18 are also provided, which are inserted concentrically into the rings 4, 8 and can either consist of the material 6 or 10 or of a third and/or fourth material.
  • FIG. 14 This gives a core in the form of a core package 14, which is figure 2 is shown.
  • Alternative core packages 14' and 14'' are described in Figs figures 4 and 5 shown.
  • the core package 14 will, as in figure 3 shown, surrounded by a circumferential winding 12 of an electrical conductor.
  • the number of windings 12 surrounding the core assembly 14 is denoted by N.
  • this inductive component in the form of a choke coil for an inverter is in the figures 4 and 5 given where in the figure 4 the partial cores 4' and 8' are designed in the form of E-shaped partial cores and in figure 5 in the form of U-shaped partial cores (4'' and 8'' and 16'' and 18'').
  • the inductive component 2 shown in this way in the form of a choke can be designed with this construction such that in S1 operation the material of the first partial core 4, for example in the form of a ferrite partial core, produces the magnetically dominant path and brings about the desired uniform inductance profile.
  • the partial cores 4 and 8 can be designed in such a way that in overload operation the permeability of the first partial core 4 collapses and the second partial core 8, which is based on an inorganically bound iron powder, for example, corrects the permeability to the desired course.
  • This arrangement can be extended to any number of different sub-cores, for example including the third core 16, 16' or 16'' and also the fourth core 18, 18' and 18'' for different load cases.
  • the cores can be geometrically congruent and, like the partial cores 16 and 18, they can also be arranged concentrically to the partial cores 4 and 8.
  • all the partial cores 4′, 4′′, 8′, 8′′, 16′, 16′′ and 18′ and 18′′ used are designed to be geometrically congruent.
  • FIG. 6 and 7 is schematically illustrated by diagrams how the effect of in the Figures 1 - 5 described inductive components is carried out magnetically.
  • the first curve I S1 is a basic current wave in continuous operation, which is essentially and ideally sinusoidal.
  • the current intensity passing through the winding 12 can look similar to the second curve, labeled I Sn . From this it can be seen that the sinusoidal wave I Sn has a significantly higher amplitude than the wave I s1 .
  • any load case of a nominal operating mode for example load case S6, is designated by the index Sn, which designates the current profile of the second current wave. It can be seen that, despite the schematic representation of the graph, the amplitude of the I Sn curve is significantly higher, in particular more than 100% higher than the amplitude of the I S1 curve in continuous operation. This means that, depending on the load, the current strength increases by more than 100%, which has a significant impact on the inductance of the inductive component 2 .
  • N L / A l 1 / 2
  • the core must carry 20 turns to generate an inductance of 100 ⁇ H.
  • the inductance LL A l N 2 be determined.
  • the inductance of the core or, in the described application, of the partial core in general can thus be determined by a person skilled in the art via the geometry-related A L value.
  • a relationship is usually shown that relates the A L value to a quantity that is at least proportional to the current I.
  • Such a representation is very schematic in figure 7 pictured.
  • a given ring can be assumed to have an A Lmax at a specific current intensity I.
  • the A L value and thus the inductance decrease proportionally; in the figure 7 the limits for 80% and for 50% with increasing current intensity I are given schematically.
  • the A L value and with it the inductance tend to 0.
  • the course of the A L value is very different for each core. This depends on its material and its geometry.
  • the geometry remains as for the Figures 1 - 3 described, is the same at least for the partial cores 4 and 8, the change in the A L value is achieved by using different magnetic materials, for example ferrites or iron composites.
  • the A L value can be calculated from the given number of turns at a given current using a graph that is generally based on the figure 7 based, the inductance of the partial core 4, 8 can be determined as a function of the current strength. It is expedient here to select at least two as partial cores from a large number of commercially available and well-defined cores, so that the relationship of the most linear possible inductance curve is fulfilled.
  • this choke coil described is to find a cost-effective arrangement in order to be able to specifically adapt the inductance profile of the choke to the application and thereby reduce the use of expensive core materials to a minimum amount.
  • the choke coils can be flexibly designed in modular design and the corresponding technical requirements can be met.
  • the inductance is to be, for example, 100 ⁇ H at zero current and maintain this value, for example, up to the peak current I D in S1 operation of, for example, 50 A, then according to the invention, for example in S4 operation, it has a peak current of 200 A, for example, about 70 % of 100 ⁇ H shall be equal to 70 ⁇ H with a deviation of not more than 10%. From the requirement that the drop is largely linear, it follows in this example that at a current of 150 A the inductance may have dropped by approx. 20% from 100 ⁇ H (equal to 80 ⁇ H) with a maximum deviation of ⁇ 10% (80 ⁇ H ⁇ 10% corresponds to 72 ⁇ H to 88 ⁇ H). Due to the variety of core sizes and materials available, the desired behavior can often be achieved through different combinations of cores, materials and windings.
  • the first sub-core consists of four segments listed by the manufacturer "Magnetics-Incorporation" under the part numbers "0058737A2" and "0058339A2".
  • the other partial cores consist of only one segment each. All segments that have identical dimensions are preferably stacked one on top of the other, resulting in two stacks of six segments each; the two stacks can be placed one inside the other to reduce the winding length (similar to, but not identical to, the partial cores 4, 6, 16 for the Figures 1 to 3 , therefore in this example reference numerals for partial cores are omitted).
  • the resulting core package 14 is wrapped with the winding 12 consisting of 10 turns.
  • the inductance formed in this way shows the course of a total inductance 22 in figure 8 compared to the desired linear progression of the linear interpolation 30.
  • the individual partial cores should preferably be selected in such a way that the winding length remains minimal. It can be seen that partial cores with the induction curve 24 cause the main part of the inductance, the partial cores with the curves 26 and 28 have a correcting effect in order to bring about the desired linear behavior of the interpolation 30 .
  • the partial cores have been selected in such a way that the corresponding inductance curves 24, 26, 28 result in the overall inductance curve 28.
  • the overall inductance curve 28 has a quasi-linear range between the current I D , the maximum permissible continuous current in S1 operation and the current I max , the maximum current permissible for the component (this can, for example, be in S4 operation or in S6 -operation occur) runs.
  • This profile is largely described by the linear interpolation 30, with the profile 22 having, if possible, less than a 30% deviation from the linear interpolation in the current interval described. The deviation is particularly preferably less than 20% and less than 10%, as stated in figure 8 is shown.
  • the course 22 has a horizontal course 32, which is between 0 A and the continuous operating current I D at a current intensity, which is 50 A in the present example.
  • Table 1 Composition of the core according to the invention with a winding of 13 turns partial core I partial core II partial core III core size "740"&"337" "740" "337” Dimensions ( ⁇ outside x ⁇ inside x height) 75 x 44.5 x 36 mm 3 or 75 x 44.5 x 36 mm 3 or 134x77x27mm 3 134x77x27mm 3 material "High Flux 60" "Kool M ⁇ 60" "Kool M ⁇ 40" number of segments 2 x 740 1 1 2 x 337 manufacturer Magnetics Incorporation 110 Delta Drive Pittsburgh PA 15238 Magnetics Incorporation 110 Delta Drive Pittsburgh PA 15238 Magnetics Incorporation 110 Delta DrivePittsburghPA 15238 Manufacturer number of the segments "740”: 0058737A2 0077737A7 0077
  • the described inductive component 2 in the form of a choke coil is part of an inverter, which is not shown here.
  • the arrangement described is particularly useful for inverters with a high switching frequency of >30 kHz.
  • Such a switching frequency is used in particular in the so-called wide band gap semiconductors, in particular semiconductor switches based on silicon carbide and aluminum nitride.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Inverter Devices (AREA)
  • Dc-Dc Converters (AREA)
  • Coils Or Transformers For Communication (AREA)
EP20193287.8A 2020-08-28 2020-08-28 Composant inductif pour un onduleur et onduleur Withdrawn EP3961660A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP20193287.8A EP3961660A1 (fr) 2020-08-28 2020-08-28 Composant inductif pour un onduleur et onduleur
PCT/EP2021/068441 WO2022042913A1 (fr) 2020-08-28 2021-07-05 Composant inductif pour onduleur et onduleur

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP20193287.8A EP3961660A1 (fr) 2020-08-28 2020-08-28 Composant inductif pour un onduleur et onduleur

Publications (1)

Publication Number Publication Date
EP3961660A1 true EP3961660A1 (fr) 2022-03-02

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EP20193287.8A Withdrawn EP3961660A1 (fr) 2020-08-28 2020-08-28 Composant inductif pour un onduleur et onduleur

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EP (1) EP3961660A1 (fr)
WO (1) WO2022042913A1 (fr)

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060125586A1 (en) * 2004-12-15 2006-06-15 Delta Electronics, Inc. Choke coil and embedded core thereof
DE102010015410A1 (de) * 2010-04-19 2011-10-20 SUMIDA Components & Modules GmbH Induktives Bauelement mit variablen Kerneigenschaften und Verfahren zu deren Einstellung
US20120326820A1 (en) * 2011-06-24 2012-12-27 Delta Electronics, Inc. Magnetic unit
DE102012207416A1 (de) * 2012-05-04 2013-11-07 Würth Elektronik eiSos Gmbh & Co. KG Ringkerndrossel
EP2940701A2 (fr) * 2014-05-02 2015-11-04 Hamilton Sundstrand Corporation Bobine d'arrêt en mode commun planaire hybride
DE102014218043A1 (de) * 2014-09-10 2016-03-10 Würth Elektronik eiSos Gmbh & Co. KG Magnetkern, induktives Bauteil und Verfahren zum Herstellen eines Magnetkerns
EP3024002A1 (fr) * 2014-11-21 2016-05-25 Hamilton Sundstrand Corporation Composant magnétique avec distribution de flux équilibré
JP2016136592A (ja) * 2015-01-23 2016-07-28 Ｊｆｅケミカル株式会社 チョークコイル用コアおよびチョークコイル
CN106887299A (zh) * 2015-12-16 2017-06-23 莱尔德电子材料(深圳)有限公司 包括锰锌铁氧体和镍锌铁氧体的共模扼流圈
WO2018117595A1 (fr) * 2016-12-20 2018-06-28 Lg Innotek Co., Ltd. Noyau magnétique, composant de bobine et composant électronique le comprenant
DE102018117211A1 (de) * 2018-07-17 2020-01-23 Sma Solar Technology Ag Kernanordnung mit magnetischen Eigenschaften für eine elektrische Vorrichtung und Drossel mit einer derartigen Kernanordnung
WO2020115360A1 (fr) * 2018-12-04 2020-06-11 Ensto Oy Conception d'onduleur comprenant un inducteur non linéaire

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060125586A1 (en) * 2004-12-15 2006-06-15 Delta Electronics, Inc. Choke coil and embedded core thereof
DE102010015410A1 (de) * 2010-04-19 2011-10-20 SUMIDA Components & Modules GmbH Induktives Bauelement mit variablen Kerneigenschaften und Verfahren zu deren Einstellung
US20120326820A1 (en) * 2011-06-24 2012-12-27 Delta Electronics, Inc. Magnetic unit
DE102012207416A1 (de) * 2012-05-04 2013-11-07 Würth Elektronik eiSos Gmbh & Co. KG Ringkerndrossel
EP2940701A2 (fr) * 2014-05-02 2015-11-04 Hamilton Sundstrand Corporation Bobine d'arrêt en mode commun planaire hybride
DE102014218043A1 (de) * 2014-09-10 2016-03-10 Würth Elektronik eiSos Gmbh & Co. KG Magnetkern, induktives Bauteil und Verfahren zum Herstellen eines Magnetkerns
EP3024002A1 (fr) * 2014-11-21 2016-05-25 Hamilton Sundstrand Corporation Composant magnétique avec distribution de flux équilibré
JP2016136592A (ja) * 2015-01-23 2016-07-28 Ｊｆｅケミカル株式会社 チョークコイル用コアおよびチョークコイル
CN106887299A (zh) * 2015-12-16 2017-06-23 莱尔德电子材料(深圳)有限公司 包括锰锌铁氧体和镍锌铁氧体的共模扼流圈
WO2018117595A1 (fr) * 2016-12-20 2018-06-28 Lg Innotek Co., Ltd. Noyau magnétique, composant de bobine et composant électronique le comprenant
DE102018117211A1 (de) * 2018-07-17 2020-01-23 Sma Solar Technology Ag Kernanordnung mit magnetischen Eigenschaften für eine elektrische Vorrichtung und Drossel mit einer derartigen Kernanordnung
WO2020115360A1 (fr) * 2018-12-04 2020-06-11 Ensto Oy Conception d'onduleur comprenant un inducteur non linéaire

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