EP0674803A1 - Tores magnetiques refroidis par air - Google Patents
Tores magnetiques refroidis par airInfo
- Publication number
- EP0674803A1 EP0674803A1 EP19940903489 EP94903489A EP0674803A1 EP 0674803 A1 EP0674803 A1 EP 0674803A1 EP 19940903489 EP19940903489 EP 19940903489 EP 94903489 A EP94903489 A EP 94903489A EP 0674803 A1 EP0674803 A1 EP 0674803A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- magnetic
- magnetic core
- lasers
- corelets
- amorphous metal
- 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
Links
- 229910000808 amorphous metal alloy Inorganic materials 0.000 claims abstract description 31
- 125000006850 spacer group Chemical group 0.000 claims description 26
- 239000004020 conductor Substances 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 239000011162 core material Substances 0.000 abstract description 79
- 238000001816 cooling Methods 0.000 abstract description 19
- 239000012809 cooling fluid Substances 0.000 abstract description 8
- 230000006698 induction Effects 0.000 abstract description 8
- 239000012774 insulation material Substances 0.000 abstract description 6
- 238000004804 winding Methods 0.000 abstract description 5
- 238000009413 insulation Methods 0.000 abstract description 4
- 239000002184 metal Substances 0.000 abstract description 3
- 229910052751 metal Inorganic materials 0.000 abstract description 3
- 239000002245 particle Substances 0.000 abstract description 3
- 230000008878 coupling Effects 0.000 abstract description 2
- 238000010168 coupling process Methods 0.000 abstract description 2
- 238000005859 coupling reaction Methods 0.000 abstract description 2
- 230000004927 fusion Effects 0.000 abstract description 2
- 238000011160 research Methods 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 31
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 11
- 239000000956 alloy Substances 0.000 description 8
- 229910045601 alloy Inorganic materials 0.000 description 8
- 238000000034 method Methods 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000005300 metallic glass Substances 0.000 description 4
- 229910000697 metglas Inorganic materials 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 230000005415 magnetization Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000003570 air Substances 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- AJDIZQLSFPQPEY-UHFFFAOYSA-N 1,1,2-Trichlorotrifluoroethane Chemical compound FC(F)(Cl)C(F)(Cl)Cl AJDIZQLSFPQPEY-UHFFFAOYSA-N 0.000 description 1
- 241000321453 Paranthias colonus Species 0.000 description 1
- FMYKJLXRRQTBOR-BZSNNMDCSA-N acetylleucyl-leucyl-norleucinal Chemical compound CCCC[C@@H](C=O)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CC(C)C)NC(C)=O FMYKJLXRRQTBOR-BZSNNMDCSA-N 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 239000000112 cooling gas Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/08—Cooling; Ventilating
- H01F27/085—Cooling by ambient air
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F3/00—Cores, Yokes, or armatures
- H01F3/04—Cores, Yokes, or armatures made from strips or ribbons
Definitions
- the present invention relates to air-cooled magnetic cores.
- Amorphous metal alloys also known as glassy metal alloys or metallic glasses, are metastable materials lacking any long range order. Amorphous metal alloys are conveniently prepared by rapid quenching from the melt using processing techniques which are conventional in the art. Examples of such amorphous metal alloys and methods for their manufacture are disclosed in commonly assigned U.S. Patent 3,856,513. The advantageous soft magnetic characteristics of amorphous metal alloys have been exploited in their wide use as materials in a variety of magnetic cores such as in distribution transformers and switch-mode power supplies.
- pulse power One application for soft magnetic cores is in pulse power.
- a low average power input with a long acquisition time is converted to an output which has high peak power delivered in a short transfer time.
- very fast magnetization reversals ranging up to 100T/ ⁇ s, occur in the core materials.
- pulse power applications include saturable reactors for magnetic pulse compression and for protection of circuit elements during turn on and pulse transformers in linear induction particle accelerators.
- Amorphous metal alloys are well suited for pulse power applications because they have high resistivities and thin ribbon geometry which allow low losses under fast magnetization reversals. (See for example, Carl H. Smith and Davidson M. Nathasi ⁇ gh, "Magnetic Properties of Metallic Glasses under Fast Pulse Excitation", IEEE CONFERENCE RECORD OF THE 16TH POWER MODULATOR SYMPOSIUM. 240 (1984).) Furthermore, amorphous metal alloys, due to their non-crystalline nature, bear no magneto-crystalline anisotropy, and consequently, may be annealed to deliver very large flux swings, with values approaching the theoretical maximum value of twice the saturation induction of the material under rapid magnetization rates.
- amorphous metal alloys have led to their use as core materials in various pulse power applications including in high power pulse sources for linear induction particle accelerators, as induction modules for coupling energy from the pulse source to the beam of these accelerators, as magnetic switches in power generators for inertial confinement fusion research, and in magnetic modulators for driving excimer lasers.
- Convection cooling of magnetic cores is limited by the available surface area of the core and is determined by the ratio of core losses to surface area. In saturable core applications, this ratio is constrained because the cross-sectional area of the core and the loss per unit volume are fixed by system parameters for a given system. Increasing the inner and outer diameters of a core would increase the available surface area but would also proportionally increase core losses resulting in the same temperature rise. Increasing the core length would also increase the available surface area but is often impractical due to space limitations in the lasers.
- cooling fluids such as oil or chlorofluorocarbons to cool magnetic cores.
- the cooling fluid is passed through channels in the core. See K.W. Reed et al., "Channel Cooling Techniques for Repetitively Pulsed Magnetic Switches", IEEE CONFERENCE RECORD OF THE 1990 NINETEENTH POWER MODULATOR SYMPOSIUM. 192 (1990) and R. Stone et al., “Core Cooling Studies at LLNL and Sandia”, INTERNATIONAL MAGNETIC PULSE COMPRESSION WORKSHOP 2. 104 (1991). R. Stone et al.
- CFC-1 13 the currently used 1 ,1 ,2-trichloro-1 ,2,2-trifiuoroethane (CFC-1 13) would have to be pressurized in order to cool adequately in higher repetition rate devices and that because a pressurized system may not be desirable for environmental, safety, and cost reasons, other cooling fluids must be considered.
- Reed et al. teach an experiment wherein a core had one vertical passage through its diameter which was formed by mounting two plates face-to-face and which had numerous channels therein formed by polymeric strips of various widths and thicknesses between the plates. The cooling oil was located in the channels.
- the reference teaches that this experimental structure simulated a practical technique for constructing cooling channels in a core by placing arrays of polycarbonate strips across the build at appropriate intervals during the winding process.
- Stone et al. teach wound cores made of layers of amorphous metal alternating with layers of insulation. Cooling fluid CFC-113 is used with or without auxiliary cooling channels. As such, the need exists in the art for a new magnetic core configuration which has improved cooling within the current cross- sectional area and lengths of cores used in lasers and which requires no cooling fluid. The use of cooling fluids adds expense to the system and is also environmentally undesirable.
- the present invention provides a magnetic core which has improved cooling within the current cross-sectional area and length of cores used in lasers and requires no cooling fluid.
- the present magnetic core comprises at least two concentric corelets wherein the corelets are formed of magnetic amorphous metal alloy and are substantially separated by a gas passage.
- the present magnetic core is advantageous to use because the heat extracted by free or forced convection cooling of the core is increased by the radial subdivision of the main core into at least two concentric corelets with a gas passage between the corelets.
- corelet as used herein means a core which is smaller in size than the main core.
- the present invention also provides a magnetic core comprising at least two concentric magnetic amorphous metal alloy cylinders which are substantially separated by gas.
- the present invention provides a magnetic core having improved cooling comprising magnetic amorphous metal alloy ribbon and at least one spacer sheet wherein the ribbon and spacer sheet are co-wound to form a core having at least two corelets of ribbon which are substantially separated by one of the spacer sheets.
- Figure 1 illustrates the present magnetic core having at least two concentric corelets.
- Figure 2 illustrates the present magnetic core having at least three concentric corelets.
- Figure 3 illustrates the present magnetic core having at least three concentric corelets and two spacer sheets.
- Figure 4 illustrates possible spacer sheet designs which may be used in the present invention.
- Magnetic core 10 has two concentric corelets 12 wherein the corelets are formed of magnetic amorphous metal alloy and are substantially separated by a gas passage 14.
- Corelets 12 may be formed from any magnetic amorphous metal alloy.
- Preferred amorphous metal alloys include the iron-based alloys disclosed in commonly assigned U.S. Patents 5,011 ,553 and 5,062,909 which are incorporated herein by reference.
- Other preferred amorphous metal alloys are the following Metglas ® alloys: ALLOY DESIGNATION NOMINAL COMPOSITION (ATOM PERCENT)
- the more preferred alloys are Co ⁇ 9 Fe 4 Ni 1 Mo 2 B 12 Si 12 ; Fe 81 B 13 5 Si 3 5 C 2 ; Fe ee Co 18 B 1B Si,; and Fe 78 Si 13 B 9 .
- the most preferred alloy is Co ⁇ 9 Fe 4 Ni 1 Mo 2 B 12 Si 12 .
- the amorphous metal alloy is prepared in the form of a ribbon which is then wound onto a standard metallic mandrel 16.
- the amorphous metal alloy is spirally co-wound with insulation to form corelet 12.
- Any insulation material which is typically used in magnetic cores may be used in the present invention. Examples of useful insulation materials are disclosed in commonly assigned U.S. Patent 5,091 ,253 which is incorporated herein by reference.
- the standard metallic mandrel 16 is used for windings which may be installed on core 10.
- Metallic sheet 18 is typically wrapped around the outside of core 10.
- Standard metallic mandrel 16 and metallic sheet 18 are typically made of stainless steel or aluminum.
- the corelets 12 are cylindrical so that the present invention provides magnetic core comprising at least two concentric magnetic amorphous metal alloy cylinders which are substantially separated by gas.
- the widths of the corelets are substantially equal.
- any inert gas may be used in the present invention.
- Preferred examples of useful gases include argon, nitrogen, and air.
- air is used.
- the gas in passage 14 may circulate by convection or may be forced to circulate. Any means for circulating the gas may be used such as a fan or a stream of compressed gas.
- the gas in passage 14 is circulated.
- the minimum width of the gas passage 14 should be sufficient so as not to produce an unacceptable pressure drop in the circulating gas.
- the maximum width of a gas passage 14 may be limited by the overall outside diameter constraint for the core 10.
- Magnetic core 20 has three concentric corelets 22 wherein the corelets 22 are formed of magnetic amorphous metal alloy and adjacent corelets are substantially separated by a passage 24 filled with circulating gas.
- Corelets 22 may be formed from any magnetic amorphous metal alloy as set forth above for corelets 12. Although not illustrated, preferably, corelets 22 comprise alternating layers of amorphous metal alloy and insulation material. Standard metallic mandrel 26 and metallic wrapper 28 may be used in making the magnetic core 20 of Figure 2.
- the corelets 22 are cylindrical so that the present invention provides magnetic core comprising at least three concentric magnetic amorphous metal alloy cylinders wherein adjacent cylinders are substantially separated by gas.
- any inert gas may be used in the magnetic core 20 of Figure 2.
- Preferred examples of useful gases include argon, nitrogen, and air.
- the gas in passage 24 may circulate by convection or may be forced to circulate. Any means for circulating the gas may be used such as a fan or a stream of compressed gas.
- the gas in passage 24 is circulated.
- the minimum width of the gas passage 24 should be sufficient so as not to produce an unacceptable pressure drop in the circulating gas.
- the maximum width of a gas passage 24 may be limited by the overall outside diameter constraint for the core 20.
- the magnetic cores of the present invention have at least two corelets.
- the maximum number of corelets may be limited by the overall outside diameter constraints for the core and by the fabrication cost.
- Another preferred magnetic core of the present invention comprises magnetic amorphous metal alloy ribbon and at least one spacer sheet wherein the ribbon and spacer sheet are co-wound to form a magnetic core having at least two ribbon corelets which are substantially separated by one of the spacer sheets. Reference is made to Figure 3 which illustrates one of these preferred magnetic cores.
- Magnetic core 30 having improved cooling comprises magnetic amorphous metal alloy ribbon and at least one spacer sheet wherein the ribbon and spacer sheet are co-wound to form magnetic core 30 having at least three ribbon corelets 32 and at least two spacer sheets 34 wherein adjacent corelets 32 are substantially separated by one of the spacer sheets 34.
- corelets 32 comprises alternating layers of magnetic amorphous metal alloy and insulation material.
- spacer sheet 34 may be used as long as the spacer sheet provides channels 36 upon co-winding with amorphous metal alloy as shown in Figure 3.
- Figure 4 illustrates various spacer sheet designs 34A, 34B, and 34C.
- the spacer sheet 34 advantageously maintains the cooling channels 36 and allows fabrication of a more mechanically stable core.
- spacer sheet 34C which has channels 36 having radial and circumferential dimensions which are substantially equal, is used in the present invention. We have found that if the radial and circumferential dimensions of the spacers are substantially equal, the total cooling surface area presented to the circulating gas in the passage between corelets is doubled.
- spacer sheet 34 is made of thermally conducting material, the spacer sheet 34 increases the total surface area exposed to the cooling gas, and thereby, increases the cooling of the corelets.
- spacer sheets 34 or spacers are preferably formed from a thermally conductive material such as aluminum or stainless steel.
- spacer sheet 34 is made of anodized aluminum.
- Standard metallic mandrel 38 and metallic wrapper 40 may be used in making the magnetic core 30 of Figure 3.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Soft Magnetic Materials (AREA)
- Transformer Cooling (AREA)
- Lasers (AREA)
Abstract
L'utilisation industrielle et médicale de lasers pompés par décharge, tels que des lasers excimères, des lasers à vapeur métallique et des lasers à CO2 pulsés, a conduit à une demande pour des fréquences de répétition accrues afin d'augmenter le débit de puissance totale. Des fréquences de répétition accrues produisent cependant des pertes plus importantes dans les tores magnétiques utilisés pour commander ces lasers. L'utilisation du refroidissement par air en ce qui concerne des configurations de tores magnétiques connues ne permet pas un refroidissement adéquat de ces tores. En conséquence, l'augmentation excessive de la température du matériau du tore magnétique entraîne des modifications indésirables des caractéristiques magnétiques, telles que l'induction de saturation réduite. En outre, l'augmentation excessive de la température peut nuire aux matériaux isolants, soit sur les enroulements en fils soit dans l'isolation interlamellaire du tore magnétique lui-même. La présente invention se rapporte à un tore magnétique qui présente un refroidissement amélioré tout en respectant la surface de section et la longueur des tores actuellement utilisés dans des lasers, et qui ne requiert pas de fluide refroidissant. Le présent tore comprend au moins deux petits tores concentriques composés d'un alliage métallique et magnétique amorphe, et sensiblement séparés par un passage de gaz. Les tores magnétiques de l'invention peuvent être utilisés selon différentes applications de puissance d'impulsions, y compris des sources d'impulsions haute puissance destinées à des accélérateurs de particules à induction linéaire, comme modules d'induction permettant de coupler l'énergie de la source d'impulsions au faisceau de ces accélérateurs, comme commutateurs magnétiques dans des générateurs de puissance destinés à la recherche en fusion par confinement inertiel, et dans des modulateurs magnétiques servant à exciter des lasers excimères, des lasers à vapeur métallique et des lasers de chaîne de production à CO2 pulsés.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US99393392A | 1992-12-18 | 1992-12-18 | |
| US993933 | 1992-12-18 | ||
| PCT/US1993/011834 WO1994015346A1 (fr) | 1992-12-18 | 1993-12-06 | Tores magnetiques refroidis par air |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP0674803A1 true EP0674803A1 (fr) | 1995-10-04 |
Family
ID=25540091
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19940903489 Ceased EP0674803A1 (fr) | 1992-12-18 | 1993-12-06 | Tores magnetiques refroidis par air |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0674803A1 (fr) |
| JP (1) | JPH08505011A (fr) |
| WO (1) | WO1994015346A1 (fr) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3608925A1 (fr) * | 2018-08-08 | 2020-02-12 | Rohde & Schwarz GmbH & Co. KG | Noyau magnétique, procédé de fabrication d'un noyau magnétique et balun doté d'un noyau magnétique |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8232747B2 (en) * | 2009-06-24 | 2012-07-31 | Scandinova Systems Ab | Particle accelerator and magnetic core arrangement for a particle accelerator |
| EP2463871B1 (fr) * | 2010-12-07 | 2017-06-14 | ABB Schweiz AG | Noyau de transformateur amorphe |
| EP2698796A1 (fr) * | 2012-08-16 | 2014-02-19 | Siemens Aktiengesellschaft | Noyau pour un transformateur ou une bobine ainsi que transformateur doté de ce noyau |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1912760C3 (de) * | 1969-03-13 | 1979-01-25 | Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt | Mit axialen Kühlkanälen durchsetzte luftgekühlte Wicklung für Transformatoren, Drosselspulen u.dgl. induktive Geräte |
| DE3928223C2 (de) * | 1988-08-25 | 1994-08-18 | Hitachi Metals Ltd | Magnetische Einrichtung für eine Hochspannungsimpulsgeneratorvorrichtung |
| US5091253A (en) * | 1990-05-18 | 1992-02-25 | Allied-Signal Inc. | Magnetic cores utilizing metallic glass ribbons and mica paper interlaminar insulation |
-
1993
- 1993-12-06 EP EP19940903489 patent/EP0674803A1/fr not_active Ceased
- 1993-12-06 WO PCT/US1993/011834 patent/WO1994015346A1/fr not_active Ceased
- 1993-12-06 JP JP51519594A patent/JPH08505011A/ja active Pending
Non-Patent Citations (1)
| Title |
|---|
| See references of WO9415346A1 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3608925A1 (fr) * | 2018-08-08 | 2020-02-12 | Rohde & Schwarz GmbH & Co. KG | Noyau magnétique, procédé de fabrication d'un noyau magnétique et balun doté d'un noyau magnétique |
Also Published As
| Publication number | Publication date |
|---|---|
| WO1994015346A1 (fr) | 1994-07-07 |
| JPH08505011A (ja) | 1996-05-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
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| 17P | Request for examination filed |
Effective date: 19950526 |
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| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE FR GB |
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| 17Q | First examination report despatched |
Effective date: 19961011 |
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| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN REFUSED |
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| 18R | Application refused |
Effective date: 19980327 |