FR3063567A1 - MAGNETIC COMPONENT AND VOLTAGE CONVERTER COMPRISING IT - Google Patents

Abstract

The invention relates to a magnetic component (10) comprising: - a magnetic core and - at least one winding (150) of a conductive wire wound around a portion of the magnetic core, wherein the magnetic core comprises a first part ( 101) and a second portion (102) which interlock with each other and which are fixed relative to each other; the first part (101) comprising an arm forming a male contact introduced into a base (102a) forming a female contact and situated in the second part (102), the wall of the arm being at a distance from the inner wall of the base (102a ); the magnetic core comprising an air gap formed by the space between the wall of the arm and the inner wall of the base (102a). The invention also relates to a voltage converter comprising the magnetic component (10).

Description

063 567

51722 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number:

(to be used only for reproduction orders) (© National registration number

COURBEVOIE © Int Cl ⁸ : H 01 F27 / 24 (2017.01)

PATENT INVENTION APPLICATION

A1

©) Date of filing: 02.03.17. © Applicant (s): VALEO SIEMENS EAUTOMOTIVE (© Priority: FRANCE SAS Simplified joint stock company - FR. @ Inventor (s): DE SOUSA LUIS and CHELGHOUM REDA. (43) Date of public availability of the request: 07.09.18 Bulletin 18/36. ©) List of documents cited in the report preliminary research: Refer to end of present booklet (© References to other national documents ® Holder (s): VALEO SIEMENS EAUTOMOTIVE related: FRANCE SAS Simplified joint-stock company. ©) Extension request (s): (© Agent (s): ARGYMA.

MAGNETIC COMPONENT AND VOLTAGE CONVERTER COMPRISING SAME.

FR 3,063,567 - A1 yv) The invention relates to a magnetic component (10) comprising:

- a magnetic core and

- at least one winding (150) of a conductive wire wound around a portion of the magnetic core, in which the magnetic core comprises a first part (101) and a second part (102) which interlock with the other and which are fixed relative to each other;

the first part (101) comprising an arm forming a male contact inserted into a base (102a), forming a female contact and located in the second part (102), the wall of the arm being spaced from the internal wall of the base (102a );

the magnetic core comprising an air gap formed by the space between the wall of the arm and the internal wall of the base (102a).

The invention also relates to a voltage converter comprising the magnetic component (10).

102 i

MAGNETIC COMPONENT AND VOLTAGE CONVERTER COMPRISING SAME

The present invention relates to a magnetic component, such as for example an inductor or a transformer operating at high frequencies. The invention also relates to a voltage converter comprising the magnetic component. In particular, the voltage converter is configured to be installed in a motor vehicle.

FIG. 1 illustrates an example of a known magnetic component 1. Typically, in the magnetic component 1, an air gap e is used to store magnetic energy. Such an air gap e is generally obtained by arranging a space between two bars 2a, 2b of the magnetic core 2. In the air gap e, the magnetic field is not uniformly rectilinear from one bar to the other, but it is deformed the edges. Generally, a coil 3 is wound along the two bars 2a, 2b. The current flowing in the coil 3 is then disturbed by the deformation of the magnetic field of the air gap e: the magnetic field coming from the air gap attracts the current flowing in the coil 3 towards the air gap, which increases the density of the current at the periphery of the coil close to the air gap, that is to say at the level of the conductor portions close to the air gap, and increases the losses in the coil 3.

A means is therefore sought to limit the effects of the air gap on the current flowing in the coil of the magnetic component.

To this end, the invention relates to a magnetic component comprising:

- a magnetic core and

at least one winding of a conductive wire wound around a portion of the magnetic core, in which the magnetic core comprises a first part and a second part which interlock with each other and which are fixed one by relation to the other;

the first part comprising an arm forming a male contact inserted into a base, forming a female contact and located in the second part, the wall of the arm being at a distance from the internal wall of the base;

the magnetic core comprising an air gap formed by the space between the wall of the arm and the internal wall of the base.

In the component according to the invention, the air gap is therefore located radially between the arm and base. The arrangement of the magnetic component according to the invention makes it possible to limit leaks due to the air gap. Thus, the winding is not disturbed by the magnetic field flowing in the air gap, which limits losses in the conductor portions close to the air gap.

According to one embodiment, an electrical and non-magnetic insulating material is added to the air gap. The addition of said material ensures the thickness of the air gap, especially in an automotive application where the magnetic core can be subjected to vibrations.

According to one embodiment, the air gap can be left free of material. For example, the air gap can be filled with air. This may in particular be the case for non-automotive applications where the magnetic component is not subject to vibration.

This can also be the case, if it can be guaranteed that the air gap space will not change due to vibrations, for example by keeping the two parts fixed.

According to one embodiment, one of the parts of the core has a section in the shape of an "E", the male-female contact being formed by the nesting of the central arm of the said section in the shape of an "E" with the corresponding part of the other part of the nucleus. In particular, the other part has a "T" shaped section, the foot of the "T" shaped section coming to be nested with the central arm of the "E" shaped section of the first part.

According to one embodiment, the magnetic component comprises first and second windings, the first winding forming a primary circuit wound around said base and the second winding forming a secondary circuit wound around at least one lateral arm of said shaped section of "E" or around said base.

According to one embodiment, the arm forming a male contact is in the form of a cylinder, and the base forms a cylindrical volume receiving said arm.

According to one embodiment, the male contacting arm is in the form of a parallelepiped, and the base forms a parallelepipedal volume receiving said arm.

The invention further relates to a voltage converter intended to convert a first voltage into a second voltage comprising:

- a magnetic component according to the invention,

- semiconductor switches configured to convert the first voltage to the second voltage via said magnetic component.

The invention will be better understood by referring to the drawings, in which:

- Figure 1 already commented illustrates an example of a magnetic component according to the prior art;

- Figures 2 to 6 illustrate examples of the magnetic component according to the invention.

FIG. 2 illustrates a first example of a magnetic component 10 according to an embodiment.

The magnetic component 10 comprises a magnetic core 100 which has a first part 101 and a second part 102 which interlock with one another and are fixed relative to each other.

An arm 101a of the first part 101 forms a male contact. The second part 102 comprises a base 102a forming a female contact. The arm 101a is introduced into the base 102a to form the core 10 as illustrated for example in FIG. 3.

FIG. 4 represents a sectional view of the magnetic component 10 illustrated in FIGS. 2 and 3. By fitting one into the other, the arm 101a and the base 102a form an air gap E. In fact, the arm 101a and the base 102a remain at a distance from each other. There is no contact between the peripheral wall of the arm 101a and the internal wall of the base 102a. Thus, the space between the wall of the arm 101a and the internal wall of the base 102a forms the air gap E of the magnetic core 100. The air gap E extends radially between the arm 101a and the base 102a.

Lines of magnetic fields C1, C2, C3, C4 traversing the magnetic core 100 are illustrated in FIG. 4. Thanks to the arrangement of the arm 101a and the base 102a, the current flowing in the winding 150 of the magnetic component 10 n ' is not disturbed by deformations of the magnetic field caused by the air gap, in particular when the winding 150 is formed on and around the base 102a.

In addition, this arrangement of the arm 101a and the base 102a allows a larger air gap E than in the prior art. In the magnetic component 10, the air gap E is formed by two air gaps: a first air gap El between the side wall of the arm 101a and the internal side wall of the base 102a; and a second air gap E2 between the end wall of the arm 101a and the bottom of the base 102a. Thus, the magnetic reluctance due to the air gap E is lower than in the prior art.

The magnetic component 10 can comprise an electrical and non-magnetic insulating material added in the air gap E, for insulation between the arm 101a and the base 102b in place of the air. In particular, the material can help center the arm 101a when it is introduced into the base 102a. The material can also guarantee that the male part 101a and the female part 102a will not move relative to each other, in particular by ensuring that the arm 101a is mounted in force in the base 102a. However, this material is not necessary, if it can be guaranteed that the two parts 101a, 102a will not move relative to each other when assembled together.

The magnetic component 100 may include a third air gap E3 between the wall 101b of the first part 101 from which the arm 101a extends, and the end of the base 102a. This third air gap E3 makes it possible not to short-circuit the air gap E between the arm 101a and the base 102a. The magnetic field in this third air gap E3 can disturb the flow of current in the winding 150, however to a lesser extent than in the prior art.

In particular, the second part 102 of the core 10 has a section in the shape of an "E" and the second part (101) has a section in the shape of a "T". The male-female contact is formed by the interlocking of the central arm 102a of the section in the form of "E" with the arm 101a of the first part 101. In this example, the base 102a therefore forms the central arm of the section in "E" shape. However, the lateral arms 102c, 102d of the “E” shape could be in the first part 101 instead of the second part 102. The arm 101a intended to come into the base 102a then forms the central arm of the shaped section of "E".

The magnetic component 10 illustrated in FIGS. 2 to 4 produces in particular a magnetic inductance. In the example illustrated in FIG. 5, the magnetic component 10 also comprises a second winding 152. In particular, this example of magnetic component 10 forms a transformer. The first winding 150 forms a primary circuit wound around the base 102b and the second winding 152 forms a secondary circuit wound around one of the side arms 102c.

In the examples illustrated in FIGS. 2 to 5, the arm 101a is in the form of a parallelepiped, and the base 102a forms a parallelepiped volume. However, the shape of the magnetic component could be different. In the example illustrated in FIG. 6, the arm 101a is in the form of a cylinder, and the base 102a forms a cylindrical volume receiving the arm 101a.

In particular, the magnetic component 10 may have a generally rectangular shape as for example in FIGS. 1 to 5, or a generally cylindrical shape as for example illustrated in FIG. 6.

The examples of magnetic component 10 can be used in a voltage converter intended to convert a first voltage into a second voltage. For this purpose, the voltage converter further comprises semiconductor switches configured to convert the first voltage into the second voltage via the magnetic component 10. In particular, the voltage converter is particularly suitable for high frequency operation, that is to say an operating frequency greater than 1 MHz, in particular between 1 MHz and 5 MHz. In particular, such an operating frequency range is possible with semiconductor switches made of silicon carbide (SiC) or gallium nitride (GaN).

Claims (7)

1. Magnetic component (10) comprising: - a magnetic core (100) and - at least one winding (150) of a conductive wire wound around a portion of the magnetic core (100), in which the magnetic core (100) comprises a first part (101) and a second part (102) which s 'fit one with the other and are fixed relative to each other; the first part (101) comprising an arm (101a) forming a male contact inserted into a base (102a), forming a female contact and located in the second part (102), the wall of the arm (101a) being spaced from the inner wall of the base (102a); the magnetic core (100) comprising an air gap (E) formed by the space between the wall of the arm (101a) and the internal wall of the base (102a). 2. Magnetic component (10) according to claim 1, in which an electrical and non-magnetic insulating material is added in the air gap (E). 3. Magnetic component (10) according to claim 1 or 2, in which one (102) of the parts of the core has an “E” shaped section, the male-female contact being formed by the interlocking of the central arm of the said section in the shape of an "E" with the corresponding part of the other part (101) of the core. 4. Magnetic component (10) according to the preceding claim, comprising a first (150) and a second (152) windings, the first winding (150) forming a primary circuit wound around said base (102a) and the second winding (152) forming a secondary circuit wound around at least one lateral arm (102c) of said "E" shaped section or around said base (102a). 5. Magnetic component (10) according to one of claims 1 to 4, in which the arm (101a) forming male contact is in the form of a cylinder, and the base (102a) forms a cylindrical volume receiving said arm (101a). 6. Magnetic component (10) according to one of claims 1 to 4, in which the arm (101a) forming male contact is in the form of a parallelepiped, and the base (102a) forms a parallelepipedal volume receiving said arm (101a). 7. Voltage converter for converting a first voltage into a second voltage comprising: - a magnetic component (10) according to one of the preceding claims, - semiconductor switches configured to convert the first voltage into the second voltage via said magnetic component (10). 1/3