Annular magnetic power unit

Abstract

The proposed annular magnetic power unit includes an annular magnetic core comprising a first partial magnetic core and a second partial magnetic core, overlapped and facing to each other, the first and second partial magnetic cores being divided by two parallel air-gaps in a first and second central magnetic core portion, a first and second left side core portion and in a first and second right side core portion; the annular power unit also including at least one electro-conductive inner coil included within an annular groove of the annular magnetic core; and left and right independent electro-conductive outer coils wound around the first and second left side core portions and the first and second right side core portions respectively.

Claims

1. An annular magnetic power unit comprising: an annular magnetic core defining an inner passage and an annular groove, said annular magnetic core comprising a first partial magnetic core and a second partial magnetic core, overlapped and facing to each other; at least said first partial magnetic core having a first annular groove constitutive of said annular groove, accessible through a surface of the first partial magnetic core facing the second partial magnetic core; said first annular groove surrounding the inner passage; at least one electro-conductive inner coil included within the annular groove; at least one electro-conductive outer coil wound around the annular magnetic core passing through the inner passage; wherein said at least one electro-conductive outer coil comprises two independent electro-conductive outer coils, named left and right independent electro-conductive outer coils; the first partial magnetic core is divided by two parallel air-gaps in three independent parts corresponding to a first central magnetic core portion, defined between said two parallel air-gaps, to a first left-side core portion and to a first right-side core portion placed on both sides of said first central magnetic core portion; the second partial magnetic core is also divided by said two parallel air-gaps in three independent parts corresponding to a second central magnetic core portion, defined between said two parallel air-gaps, to a second left-side core portion and to a second right-side core portion placed on both sides of said second central magnetic core portion; the two-parallel air-gaps are defined by two parallel gap planes perpendicular to a surface of the first partial magnetic core facing the second partial magnetic core, both parallel gap planes passing through the inner passage; the first central magnetic core portion and the second central magnetic core portion define correspondent first and second bridges across the inner passage, dividing said inner passage in a left inner passage and a right inner passage; the left electro-conductive outer coil passes through the left inner passage and surrounds the first and second left side core portions; and the right electro-conductive outer coil passes through the right inner passage and surrounds the first and second right side core portions.

2. The annular magnetic power unit according to claim 1, wherein the electro-conductive inner coil comprises a planar transformer constituted by a succession of stacked windings with interleaved insulating laminar members, said stacked windings being connected to each other.

3. The annular magnetic power unit according to claim 2, wherein said succession of stacked windings comprises a variable number of at least one of stacked printed circuit boards windings and copper windings.

4. The annular magnetic power unit according to claim 3, wherein each copper winding is a copper sheet having a sinuous slit or a winded copper yarn.

5. The annular magnetic power unit according to claim 3, wherein each printed circuit board winding includes a sinuous conductive circuit printed on one or both sides of said printed circuit board winding.

6. The annular magnetic power unit according to claim 3, wherein a connection between said stacked windings is produced by connecting pins inserted through aligned orifices of the printed circuit boards windings and the copper windings.

7. The annular magnetic power unit according to claim 1, wherein said second partial magnetic core has a second annular groove also constitutive of said annular groove, accessible through a surface of the second partial magnetic core facing the first partial magnetic core, said second annular groove surrounding the inner passage.

8. The annular magnetic power unit according to claim 7, wherein the first and second partial magnetic cores are symmetrical.

9. The annular magnetic power unit according to claim 1, wherein the left electro-conductive outer coil is different from the right electro-conductive outer coil.

10. The annular magnetic power unit according to claim 1, wherein the annular magnetic core, the left and right independent electro-conductive outer coils, and the electro-conductive inner coil are embedded in a single mass of insulating polyurethane resin which covers the assembly.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) The foregoing and other advantages and features will be more fully understood from the following detailed description of an embodiment with reference to the accompanying drawings, to be taken in an illustrative and not limitative, in which:

(2) FIG. 1 shows a perspective view of the annular magnetic power unit without the cover made of a mass of insulating polyurethane resin wherein the left outer coil has less windings than the right outer coil;

(3) FIG. 2 shows a longitudinal section of the embodiment shown on FIG. 1 being the section made across the left and right inner passages;

(4) FIG. 3 shows an exploded vision of the annular magnetic power unit shown on FIG. 1, indicating with arrows the magnetic fields associated to each of the outer coils and inner transformer.

DETAILED DESCRIPTION OF AN EMBODIMENT

(5) The foregoing and other advantages and features will be more fully understood from the following detailed description of an embodiment with reference to the accompanying drawings, to be taken in an illustrative and not limitative, in which:

(6) The present invention corresponds to an annular magnetic power unit which, according to a preferred embodiment shown on FIGS. 1, 2 and 3, includes an annular magnetic core 1 defined around an inner passage 2, which is made of a ferromagnetic material, and including one electro-conductive inner coil 30 encapsulated within an annular groove 5 defined inside the annular magnetic core 1, and two electro-conductive outer coils 40 wound around the annular magnetic core 1 passing each wound through the inner passage 2.

(7) To create said annular groove 5 and to make it accessible for the insertion of the inner coil 30, the annular magnetic core 1 is composed by a first partial magnetic core 10 and a second partial magnetic core 20 overlapped.

(8) First partial magnetic cores 10 include a first annular groove 15 (FIG. 2) surrounding the inner passage 2 accessible through a surface of the first partial magnetic core 10 facing the second partial magnetic core 20.

(9) Second partial magnetic core 20 is symmetric regard the first partial magnetic core 10, and includes a second annular groove 25 (FIG. 2) surrounding the inner passage 2 accessible through a surface of the second partial magnetic core 20 facing the first partial magnetic core 10.

(10) The inner coil 30 is placed in the first and second annular passage 15 and 25, surrounding the inner passage 2 within the annular magnetic core 1.

(11) Furthermore, the annular magnetic core 1 is divided in three portions spaced apart by two parallel air-gaps 50. Each air-gap 50 is defined in a gap plane perpendicular to the surface of the first partial magnetic core 10 facing the second partial magnetic core 20, and therefore said air-gap 50 not interfering the magnetic field B3 generated by the inner coil 30.

(12) As can be seen in FIG. 2, Said two air-gaps 50 divide the first partial magnetic core 10 in a first left partial magnetic core 13, a first right partial magnetic core 14 and a first central partial magnetic core 11 placed in-between, and divide the second partial magnetic core 20 in a second left partial magnetic core 23, a second right partial magnetic core 24 and a second central partial magnetic core 21 placed in-between.

(13) Each of said two gap planes which define the air-gaps 50 cross the inner passage 2. Each the first and the second central partial magnetic core 11 and 21 have a portion on each side of the inner passage 2, and a correspondent first and second bridge 12 connecting said portions across the inner passage 2. Said first and second bridges 12 divide the inner passage 2 in a left inner passage 3 and a right inner passage 4.

(14) According to this description the annular magnetic core 1 is formed by six different parts, three of them corresponding to the first partial magnetic core 10, and other three corresponding to the second partial magnetic core 20.

(15) The two electro-conductive outer coils 40 previously mentioned wound around the annular magnetic core 1 are, according to the present embodiment of the invention, a left outer coil 43 and a right outer coil 44. The left outer coil 43 is wound around the first and second left partial magnetic cores 13 and 23 passing each wound through the left inner passage 3, and the right outer coil 44 is wound around the first and second right partial magnetic cores 14 and 24 passing each wound through the right inner passage 4.

(16) The air-gaps 50 interrupt the magnetic field B1 and B2 generated in the annular magnetic core 1 by the outer coils 40, preventing interferences and inefficiencies.

(17) Being the left outer coil 43 different from the right outer coil 44, its performances will be also different, permitting the annular magnetic unit to be adaptable to different necessities using the left, the right or both outer coils 43, 44.

(18) It is also proposed the inner coil 30 providing a planar transformer being composed by a plurality of windings stacked together with interleaved insulating laminar members as per the method disclosed in the cited WO2004003947.

(19) According to the present embodiment said windings stacked together include variable number of stacked printed circuit boards windings and copper windings.

(20) Each printed circuit board includes a winding circuit printed on one or both faces of it, creating a planar winding.

(21) The copper windings can be produced by a die-cutting process on a copper sheet, creating a planar winding. Alternatively said copper winding can be created by simple bending of a copper yarn.

(22) Each of the windings stacked together include an extension exiting the annular groove 5, protruding from the annular magnetic core 1. Said extensions including aligned orifices where connecting pins 31 are inserted producing the connection between the windings stacked together.

(23) The annular magnetic power unit will be preferably covered with a mass of insulating polyurethane resin (not shown) which isolates electrically the components. More preferably said polyurethane resin penetrates within the annular groove and also penetrates between the stacked windings of the inner coil 30.

(24) In the disclosed embodiment the magnetic power unit will include a planar transformer confined in the inner passage this arrangement in this way assuring a very low leakage inductance having a maximum value of around 2 μH, and two external inductors one operating a parallel external inductor and the second one as a resonant inductor galvanically isolated.

(25) Also, it should be mentioned that left inner passage 3 and a right inner passage 4, also can be used for the insertion there through of a pipe to evacuate heat using the solution exposed in EP16002354 cited in the background.

(26) It will be understood that various parts of one embodiment of the invention can be freely combined with parts described in other embodiments, even being said combination not explicitly described, provided there is no harm in such combination.