CN116130226A

CN116130226A - Inductor and power control device

Info

Publication number: CN116130226A
Application number: CN202310033520.1A
Authority: CN
Inventors: 王子京; 张浩军; 陆修远; 肖尧; 鲁传家; 景遐明; 梁金坤; 王志成
Original assignee: Huawei Digital Power Technologies Co Ltd
Current assignee: Huawei Digital Power Technologies Co Ltd
Priority date: 2023-01-10
Filing date: 2023-01-10
Publication date: 2023-05-16

Abstract

The application provides an inductor and power control device, the inductor includes: a coil, and a magnetic core surrounding the coil. The coil includes: a wire, and a composite insulating layer surrounding the wire. The composite insulating layer comprises at least: a first insulating layer and a second insulating layer. The first insulating layer wraps the surface of the wire, and the second insulating layer wraps the surface of the first insulating layer. The first insulating layer is different from the second insulating layer in material or structure. In this embodiment of the application, through setting up the composite insulation layer of parcel wire in the coil, composite insulation layer includes two-layer insulating layer at least, can improve the insulating properties between wire and the magnetic powder in the magnetic core in the coil, and then improves the withstand voltage performance of inductor, improves the reliability of inductor.

Description

Inductor and power control device

Technical Field

The present disclosure relates to power control technologies, and in particular, to an inductor and a power control device.

Background

With the rapid development of power electronics technology, inductors are widely used in various power control devices. The inductor can play roles in energy storage, voltage boosting, filtering, electromagnetic interference elimination and the like in the power control device, and is an indispensable component in the power control device. With the rapid development of emerging digital industries (such as artificial intelligence, big data, cloud computing and the like) and new energy industries (such as photovoltaics, electric automobiles and the like), the requirements of power control devices on the performances of inductance, saturation current, direct current resistance, direct current/alternating current withstand voltage, turn-to-turn withstand voltage and the like of inductors are higher and higher.

In the related art, the inductor is formed by implanting the coil into a mold and filling the magnetic powder for die casting, however, the inductor is limited by insulation performance between the wire in the coil and the magnetic powder, and has poor withstand voltage performance, for example, the voltage bearable by the inductor in the related art is about 50V to 60V, which is difficult to meet the requirement of the novel power control device.

Disclosure of Invention

The embodiment of the application provides an inductor and a power control device, which are used for improving the voltage resistance of the inductor.

In a first aspect, embodiments of the present application provide an inductor that may include: a coil, and a magnetic core surrounding the coil. The coil may include: a wire, and a composite insulating layer surrounding the wire. The composite insulating layer may include at least: the first insulating layer wraps the surface of the lead, the second insulating layer wraps the surface of the first insulating layer, and the first insulating layer and the second insulating layer are different in material or structure. The wires in the coil can generate a magnetic field after being electrified, the wires can be made of conductive materials such as metal, for example, the wires can be copper wires, and when the coil is in specific implementation, the two ends of the coil can be not wrapped by the magnetic core, or the two ends of the coil can be led out by adopting the leads, so that current can be provided for the coil through the two ends of the coil. The composite insulating layer may serve as an insulating wire and a magnetic core, and in this embodiment, the composite insulating layer includes a first insulating layer and a second insulating layer, and in a specific implementation, the composite insulating layer may also include three, four or more insulating layers, where the number of insulating layers in the composite insulating layer is not limited.

In the inductor provided by the embodiment of the application, through setting up the composite insulation layer of parcel wire in the coil, the composite insulation layer includes two-layer insulating layer at least, can improve the insulating properties between the magnetic powder in wire and the magnetic core in the coil, and then improves the withstand voltage performance of inductor, improves the reliability of inductor. For example, the ac working voltage range applicable to the inductor in the embodiment of the present application may be 50V to 5000V, and the applicable power range may be 10W to 500kW, so the inductor provided in the embodiment of the present application may meet the withstand voltage requirements of various types of power control devices.

In the embodiment of the present application, the material of the magnetic core may be metal soft magnetic powder. Alternatively, the material of the magnetic core may be granulated powder composed of metal magnetic powder and a polymer binder, and the polymer binder may be added in an amount of 0.5 to 5.0% by weight of the metal powder. In addition, diluents, coupling agents, toughening agents, etc. may be added to the granulated powder to aid in forming the powder and to improve the corresponding properties.

The metal soft magnetic powder material can be one or more than one of carbonyl iron powder, reduced iron powder, atomized iron powder, ferrosilicon aluminum powder, ferrosilicon chromium powder, iron-based amorphous magnetic powder, iron-based nanocrystalline powder, iron-nickel magnetic powder and molybdenum permalloy powder. The polymer binder may be epoxy resin series, phenolic resin series, silicone resin series, and other resins and their related modified products.

The coil in the embodiment of the application may be a vertically wound flat wire or a round wire, that is, the section of the coil may be rectangular or circular. Of course, the cross section of the coil may be other shapes, and is not limited herein.

In the manufacturing process, each insulating layer in the composite insulating layer can be formed on the lead, the lead wrapping the composite insulating layer is surrounded to be a coil, then the coil and the magnetic core material are placed in a die, the coil and the magnetic core material are integrally formed into the inductor by adopting a pressing process, and the pressure of the pressing process can be less than or equal to 400MPa. The pressing process can comprise the processes of coil placement, die assembly, preheating, powder feeding, pressing, demoulding and the like.

In the embodiment of the present application, the composite insulating layer may have various implementation manners, and the following details are given for implementation manners of the composite insulating layer in the embodiment of the present application.

The implementation mode is as follows:

the first insulating layer and the second insulating layer are both strip-shaped organic films, the first insulating layer is tightly wound on the surface of the lead, the second insulating layer is tightly wound on the surface of the first insulating layer, and the winding path of the first insulating layer is different from the winding path of the second insulating layer. In the first implementation manner, taking the case that the composite insulating layer includes the first insulating layer and the second insulating layer as an example, in a specific implementation, the organic film may be rewound on the surface of the second insulating layer, and the number of layers of the insulating layers in the composite insulating layer is not limited here.

In the manufacturing process, firstly, a strip-shaped organic film is manufactured by adopting an organic material, then, the strip-shaped organic film is wound on the surface of the wire in a circle-by-circle mode to obtain a first insulating layer wrapping the wire, and the strip-shaped organic film is wound on the surface of the first insulating layer in a circle-by-circle mode in a similar mode to obtain a second insulating layer wrapping the first insulating layer. In this embodiment, the insulating layer wound from the first end to the second end of the wire is regarded as the same insulating layer, for example, during the winding process, a certain circle of organic film may overlap with the previous circle of organic film, and the two circles of organic film layers still belong to the same insulating layer.

The winding path of the first insulating layer is different from the winding path of the second insulating layer. For example, the first insulating layer may be obtained by winding the organic thin film from the first end to the second end of the wire, and the second insulating layer may be obtained by winding the organic thin film from the second end to the first end of the wire, that is, the winding direction of the first insulating layer may be different from the winding direction of the second insulating layer. As another example, the winding angle of the first insulating layer and the second insulating layer may be different. The specific winding manner of the first insulating layer and the second insulating layer is not limited here as long as the winding paths of the first insulating layer and the second insulating layer are different.

In the manufacturing process of the inductor, the coil and the magnetic core material are required to be placed in a mold, and the coil and the magnetic core material are integrally formed by adopting a pressing process. If only the first insulating layer is arranged on the surface of the wire and the second insulating layer is not arranged, the magnetic powder easily enters the surface of the wire through the edge of the first insulating layer under the action of pressure in the pressing process, so that the insulating performance of the wire and the magnetic powder in the magnetic core is affected. In this embodiment of the application, the winding route of first insulating layer is different with the winding route of second insulating layer, can make the second insulating layer can push down the edge of first insulating layer, like this, in the suppression technology in-process, the magnetic powder is difficult to enter into the wire surface through the edge of first insulating layer, has improved the insulating properties between magnetic powder in wire and the magnetic core, and then improves the withstand voltage performance of inductor. And the manufacturing process of the second insulating layer is similar to that of the first insulating layer, and the addition of the second insulating layer does not increase the process cost, so that mass production is facilitated.

In one possible implementation, the materials of the first insulating layer and the second insulating layer may include, but are not limited to, low water absorbing resin materials such as Polyimide (PI), polyamide 6T resin (Polyamide 6T, pa 6T), polyamide 9T resin (Polyamide 9T, pa 9T), polyphenylene sulfide (Polyphenylene sulfide, PPS), polyethylene terephthalate (Polyethylene terephthalate, PET), polyoxyxylene (Polyphenylene oxide, PPE), polyethylene (PE), polyetherimide (PEI), polyoxymethylene (POM), polyamide 12 resin (Polyamide 12, pa 12), polysulfone (Polysulfone, PSU), polyetheretherketone (Polyether ether ketone, PEEK), and modified materials thereof. The thickness of the first insulating layer may be in the range of 0.003mm to 0.1mm, for example, the thickness of the first insulating layer may be 0.003mm, 0.05mm, or 0.1mm. The thickness of the second insulating layer may be in the range of 0.003mm to 0.1mm, for example, the thickness of the second insulating layer may be 0.003mm, 0.05mm or 0.1mm. The total thickness of the composite insulation layer may be in the range of 0.05mm to 0.30mm, for example, the total thickness of the composite insulation layer may be 0.05mm, 0.2mm or 0.30mm.

The implementation mode II is as follows:

the first insulating layer is a strip-shaped organic film and is tightly wound on the surface of the wire. The second insulating layer may include: the resin material, the second insulating layer is hollow tubular, and the second insulating layer cover is located the surface of first insulating layer.

The first insulating layer is made of an organic film, and the organic film has good insulating property but poor mechanical property. The second insulating layer is made of resin materials, the mechanical properties of the cured resin materials are good, the second insulating layer has certain hardness, and the second insulating layer is arranged on the outer side of the first insulating layer, so that the coil can be protected, and the coil is prevented from being deformed in the pressing process. In the second implementation mode, the composite insulating layer of the organic film and the resin material is arranged in the coil, so that the inductor has good mechanical property on the basis of good insulating property, and the reliability of the inductor is improved.

In the manufacturing process, the strip-shaped organic film can be manufactured by adopting an organic material, and then the strip-shaped organic film is wound on the surface of the wire in a circle-by-circle manner, so that the first insulating layer wrapping the wire is obtained. The material of the first insulating layer may include, but is not limited to, PI, PA6T, PA9T, PPS, PET, PPE, PE, PEI, POM, PA, PSU, PEEK, and other low water absorbent resin materials and modified materials thereof. The thickness of the first insulating layer may be in the range of 0.003mm to 0.1mm, for example, the thickness of the first insulating layer may be 0.003mm, 0.05mm, or 0.1mm.

In one possible implementation, the material of the second insulating layer may include a resin material such as polyphenylene sulfide. The resin material melted into a liquid state may be extruded onto the surface of the first insulating layer, and after cooling, a second insulating layer is formed to wrap the first insulating layer. The thickness of the second insulating layer obtained by the manufacturing method may be in the range of 0.05mm to 0.3mm, preferably in the range of 0.1mm to 0.25mm, and for example, the thickness of the second insulating layer may be 0.05mm, 0.1mm, 0.2mm, 0.25mm or 0.3mm.

In another possible implementation, the material of the second insulating layer may include a resin material such as epoxy. A second insulating layer may be formed on the surface of the first insulating layer by powder spraying. The thickness of the second insulating layer obtained by the manufacturing method can be in the range of 0.2mm to 0.25mm, for example, the thickness of the second insulating layer can be 0.2mm, 0.22mm or 0.25mm.

The total thickness of the composite insulation layer may be in the range of 0.05mm to 0.30mm, for example, the total thickness of the composite insulation layer may be 0.05mm, 0.2mm or 0.30mm.

And the implementation mode is three:

the first insulating layer may be a paint film, for example, the material of the paint film may include unsaturated polyester imide or polyimide, or the like. The first insulating layer is hollow tubular, and the surface of wire is located to first insulating layer cover. The second insulating layer may include: the resin material, the second insulating layer is hollow tubular, and the second insulating layer cover is located the surface of first insulating layer.

The first insulating layer is a paint film, the mechanical property of the paint film is poor, and the paint film is easy to be thinned under the action of pressure in the pressing process. The second insulating layer is made of resin materials, the mechanical properties of the cured resin materials are good, the second insulating layer has certain hardness, and the second insulating layer is arranged on the outer side of the first insulating layer, so that the coil can be protected, and the coil is prevented from being deformed in the pressing process.

In the manufacturing process, the paint can be made into liquid impregnating varnish, the wire is put into the impregnating varnish, and vacuum pressure impregnation is adopted until the surface of the wire forms a complete paint film, namely a first insulating layer is formed on the surface of the wire. The thickness of the first insulating layer may be in the range of 0.05mm to 0.2mm, for example, the thickness of the first insulating layer may be 0.05mm, 0.1mm, or 0.2mm.

The implementation mode is four:

the first insulating layer is a paint film, and for example, the material of the paint film may include unsaturated polyester imide, polyimide or the like. The first insulating layer is hollow tubular, and the surface of wire is located to first insulating layer cover. The second insulating layer is a strip-shaped organic film and is tightly wound on the surface of the first insulating layer.

The first insulating layer is a paint film, the mechanical property of the paint film is poor, and the paint film is easy to be thinned under the action of pressure in the pressing process. The second insulating layer is an organic film, the mechanical property of the organic film is good, and the second insulating layer is arranged on the outer side of the first insulating layer, so that the coil can be protected, and the coil is prevented from being deformed in the pressing process.

In the manufacturing process, the paint can be made into liquid impregnating varnish, the wire is put into the impregnating varnish, and vacuum pressure impregnation is adopted until the surface of the wire forms a complete paint film, namely a first insulating layer is formed on the surface of the wire. And winding the strip-shaped organic film on the surface of the first insulating layer in a circle-by-circle manner to obtain a second insulating layer wrapping the first insulating layer.

In one possible implementation, the thickness of the first insulating layer may be in the range of 0.05mm to 0.2mm, for example, the thickness of the first insulating layer may be 0.05mm, 0.1mm, or 0.2mm. The thickness of the second insulating layer is in the range of 0.003mm to 0.1mm, for example, the thickness of the second insulating layer may be 0.003mm, 0.05mm or 0.1mm. The material of the second insulating layer may include, but is not limited to, PI, PA6T, PA9T, PPS, PET, PPE, PE, PEI, POM, PA, PSU, PEEK, and other low water absorbent resin materials and modified materials thereof.

The implementation mode is five:

the first insulating layer is a strip-shaped organic film and is tightly wound on the surface of the wire. The second insulating layer is a paint film, is hollow and tubular, and is sleeved on the surface of the first insulating layer.

In the fifth implementation mode, the composite insulating layer formed by the organic film and the paint film is arranged in the coil, so that the insulating performance between the lead and the magnetic powder can be improved, and the voltage-resistant performance of the inductor can be improved.

The material of the second insulating layer may include unsaturated polyester imide or polyimide, or the like. In the manufacturing process, the paint can be made into liquid impregnating varnish, the wire wrapped with the first insulating layer is immersed in the impregnating varnish by vacuum pressure until a complete paint film is formed on the surface of the first insulating layer, namely, a second insulating layer is formed on the surface of the first insulating layer. The thickness of the second insulating layer may be in the range of 0.05mm to 0.2mm, for example, the thickness of the second insulating layer may be 0.05mm, 0.1mm, or 0.2mm.

In this embodiment, the structure of the composite insulating layer is described by taking the first to fifth implementation modes as examples, and in the specific implementation, other implementation modes may be adopted for the composite insulating layer, which are not illustrated here.

The above describes various implementation manners of the composite insulating layer in the embodiment of the present application, in order to further improve the insulating performance of the magnetic powder in the wire and the magnetic core, the inductor in the embodiment of the present application may further include: the insulating protector is described in detail below.

The inductor may further include: and the part of the coil except the end part is positioned in the insulating protection part, and the magnetic core wraps the insulating protection part. Therefore, the insulation performance between the wires in the coil and the magnetic powder in the magnetic core can be further improved, and the voltage-resistant performance of the inductor is further improved. And the insulating protection piece can play the effect of protecting the coil, improves the structural reliability of the inductor.

In some embodiments of the present application, the insulating protector may include: the bottom shell is provided with a first groove, and the upper cover is provided with a second groove. The first groove and the second groove can form a containing space for containing the coil and two through holes U connected with the containing space, the coil is located in the containing space, and two ends of the coil respectively penetrate through the two through holes U. In addition, the gap between the coil and the insulating protection piece is filled with resin materials, so that the position of the coil is fixed, and the structural reliability of the inductor is improved. In specific implementations, the material of the bottom chassis (or the upper cover) may include glass fiber, carbon fiber, etc., or the material of the bottom chassis (or the upper cover) may include, but is not limited to, PI, PA6T, PA9T, PPS, PET, PPE, PE, PEI, POM, PA, PSU, PEEK, etc. low water absorbent resin materials and modified materials thereof. The thickness of the bottom chassis (or upper cover) may be in the range of 0.1mm to 0.25mm, for example, the thickness of the bottom chassis (or upper cover) may be 0.1mm, 0.2mm, or 0.25mm.

In the installation process of the insulating protection piece, the coil can be firstly placed in the first groove of the bottom shell, and then the upper cover is buckled on the bottom shell so as to insulate the structure of the protection piece. Then, a resin material is injected into a gap between the insulating protector and the coil.

In other embodiments of the present application, the insulating protector may be insulating paper, and the insulating paper wraps the portion of the coil except for the end portion. In the manufacturing process, the insulating paper can be uniformly wound on the surface of the coil. In particular implementations, the insulating paper may include, but is not limited to, aramid paper, DMD paper, green shell paper, fiberglass paper, and the like. The thickness of the insulating paper may be in the range of 0.05mm to 0.13mm, for example, the thickness of the insulating paper may be 0.05mm, 0.08mm or 0.13mm.

The coil may be any one of the above-mentioned implementations one to five, i.e. the surface of the wire in the coil may be wrapped with a composite insulating layer.

In a second aspect, embodiments of the present application also provide another inductor, the inductor may include: coil, insulating protection piece and magnetic core, the part of coil except for the tip is located insulating protection piece, and the magnetic core parcel insulating protection piece. Wherein the coil may include: a wire, and an insulating layer surrounding the wire.

Similar to the embodiment in the first aspect described above, by providing the insulating protector, the insulating protector can play a role of insulation and protection, and the withstand voltage performance and the structural reliability of the inductor can be further improved. The specific implementation manner of the insulating protection member in the second aspect may be implemented with reference to the embodiment in the first aspect, and the repetition is not repeated.

The embodiment in the first aspect is different from the embodiment in the first aspect in that: in an embodiment of the second aspect, the coil may be any one of the above-mentioned implementation one to implementation five, that is, a surface of a wire in the coil may be wrapped with a composite insulating layer; alternatively, a single insulating layer may be provided on the surface of the wire in the coil, and for example, the coil may be any one of a film-covered wire, an enamel-covered wire, or a plastic-covered wire.

Illustratively, the insulating layer may include: the resin material may be, for example, polyphenylene sulfide resin. The insulating layer is hollow tubular, and the insulating layer cover is located the surface of wire. The thickness of the insulating layer may be between 0.1mm and 0.25mm, for example, the thickness of the insulating layer may be 0.1mm, 0.22mm or 0.25mm. The insulating layer is made of resin materials, so that a thicker insulating layer can be obtained, and the insulating performance and the mechanical performance of the insulating layer are better, so that the voltage resistance of the inductor is better.

In a third aspect, embodiments of the present application further provide a power control apparatus, where the power control apparatus may include: any one of the inductors, and a power conversion circuit, wherein the power conversion circuit is electrically connected with the inductor and is used for converting alternating current and direct current. Since the inductor is excellent in withstand voltage performance and reliability, the power control device including any of the above inductors is also excellent in performance.

The power control device can be applied to power electronic or power conversion equipment such as photovoltaic inverters, on-board charging (OBC), charging piles, uninterruptible power systems (Uninterruptible Power System, UPS), base station power supply systems and the like.

Drawings

Fig. 1 is a schematic structural diagram of an inductor according to an embodiment of the present disclosure;

FIG. 2 is a schematic cross-sectional view taken at the dashed line L in FIG. 1;

FIG. 3 is another schematic cross-sectional view of the broken line L in FIG. 1;

FIG. 4 is a schematic view of a coil structure in an embodiment of the present application;

FIG. 5 is a schematic view of another coil structure in an embodiment of the present application;

FIG. 6 is a schematic view of another coil structure in an embodiment of the present application;

fig. 7 is a schematic diagram of another structure of an inductor according to an embodiment of the present application;

FIG. 8 is a schematic view of an installation process of an insulation protector according to an embodiment of the present application;

fig. 9 is another schematic structural diagram of an inductor according to an embodiment of the present application.

Reference numerals:

a 100-coil; 11-conducting wires; 12-a composite insulating layer; 121-a first insulating layer; 122-a second insulating layer; 200-magnetic cores; 300-insulating protection member; 31-bottom case; 311-a first groove; 32-an upper cover; u-through holes.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the present application will be described in further detail with reference to the accompanying drawings.

It should be noted that the same reference numerals in the drawings of the present application denote the same or similar structures, and thus a repetitive description thereof will be omitted. The words expressing the positions and directions described in the present application are described by taking the drawings as an example, but can be changed according to the needs, and all the changes are included in the protection scope of the present application. The drawings of the present application are merely schematic representations, not to scale.

In order to improve the voltage withstand performance of an inductor, embodiments of the present application provide an inductor and a power control device. The inductor can be applied to various types of power control devices, and can play roles in energy storage, voltage boosting, filtering, electromagnetic interference elimination and the like in the power control devices. The power control device can be applied to power electronic or power conversion equipment such as photovoltaic inverters, on-board charging (OBC), charging piles, uninterruptible power systems (Uninterruptible Power System, UPS), base station power supply systems and the like.

Fig. 1 is a schematic structural diagram of an inductor provided in an embodiment of the present application, fig. 2 is a schematic sectional view of a broken line L in fig. 1, and in combination with fig. 1 and fig. 2, the inductor provided in an embodiment of the present application may include: a coil 100, and a magnetic core 200 surrounding the coil 100. The coil 100 may include: a wire 11, and a composite insulating layer 12 surrounding the wire 11. The composite insulating layer 12 may include at least: the first insulating layer 121 and the second insulating layer 122, the first insulating layer 121 wraps the surface of the wire 11, the second insulating layer 122 wraps the surface of the first insulating layer 121, and the first insulating layer 121 and the second insulating layer 122 are different in material or structure. The conductive wire 11 in the coil 100 may generate a magnetic field after being electrified, and the conductive wire 11 may be made of a conductive material such as metal, for example, the conductive wire may be a copper wire, and in a specific implementation, two ends of the coil 100 may not be wrapped by the magnetic core 200, or two ends of the coil 100 may be led out by a lead wire, so that current may be provided to the coil 100 through two ends of the coil 100. The composite insulating layer 12 may serve as the insulating wire 11 and the magnetic core 200, and in this embodiment, the composite insulating layer 12 includes the first insulating layer 121 and the second insulating layer 122, and in a specific implementation, the composite insulating layer 12 may also include three, four or more insulating layers, which are not limited herein.

In the inductor provided by the embodiment of the application, the composite insulating layer 12 wrapping the wire 11 is arranged in the coil 100, and the composite insulating layer 12 at least comprises two layers of insulating layers, so that the insulating performance between the wire 11 in the coil 100 and the magnetic powder in the magnetic core 200 can be improved, the voltage withstanding performance of the inductor is further improved, and the reliability of the inductor is improved. For example, the ac working voltage range applicable to the inductor in the embodiment of the present application may be 50V to 5000V, and the applicable power range may be 10W to 500kW, so the inductor provided in the embodiment of the present application may meet the withstand voltage requirements of various types of power control devices.

In the embodiment of the present application, the material of the magnetic core 200 may be metal soft magnetic powder. Alternatively, the material of the magnetic core 200 may be granulated powder composed of metal magnetic powder and a polymer binder, and the polymer binder may be added in an amount of 0.5 to 5.0% by weight of the metal powder. In addition, diluents, coupling agents, toughening agents, etc. may be added to the granulated powder to aid in forming the powder and to improve the corresponding properties.

As shown in fig. 2, the coil 100 in the embodiment of the present application may be a vertically wound flat wire, that is, the cross section of the coil 100 may be rectangular. Fig. 3 is another schematic cross-sectional view of the broken line L in fig. 1, and as shown in fig. 3, the coil 100 in the embodiment of the present application may also be a vertically wound round line, that is, the cross-section of the coil 100 may also be a circle. Of course, the cross section of the coil 100 may be other shapes, and is not limited herein.

In the embodiment of the present application, the composite insulating layer may have various implementation manners, and in the following, a detailed description is given of an implementation manner of the composite insulating layer in the embodiment of the present application with reference to the accompanying drawings.

The implementation mode is as follows:

fig. 4 is a schematic structural diagram of a coil according to an embodiment of the present application, and referring to fig. 2 and fig. 4, the first insulating layer 121 and the second insulating layer 122 are both strip-shaped organic films, the first insulating layer 121 is tightly wound on the surface of a wire (the wire is wrapped by the composite insulating layer 12 in fig. 4, and the wire is not shown), the second insulating layer 122 is tightly wound on the surface of the first insulating layer 121, and the winding path of the first insulating layer 121 is different from the winding path of the second insulating layer 122. In order to facilitate distinguishing the first insulating layer 121 from the second insulating layer 122, the edges of the first insulating layer 121 are indicated by thinner lines and the lines of the second insulating layer 122 are indicated by thicker lines in fig. 4. In the first embodiment, taking the composite insulating layer 12 including the first insulating layer 121 and the second insulating layer 122 as an example, in a specific implementation, an organic film may be further wound on the surface of the second insulating layer 122, and the number of layers of the insulating layers in the composite insulating layer 12 is not limited here.

In the manufacturing process, the strip-shaped organic film is manufactured by adopting an organic material, then the strip-shaped organic film is wound on the surface of the wire in a circle-by-circle manner to obtain the first insulating layer 121 wrapping the wire, and the strip-shaped organic film is wound on the surface of the first insulating layer 121 in a circle-by-circle manner to obtain the second insulating layer 122 wrapping the first insulating layer 121. In this embodiment, the insulating layer wound from the first end to the second end of the wire is regarded as the same insulating layer, for example, during the winding process, a certain circle of organic film may overlap with the previous circle of organic film, and the two circles of organic film layers still belong to the same insulating layer.

The winding path of the first insulating layer 121 is different from the winding path of the second insulating layer 122. For example, the first insulating layer 121 may be obtained by winding an organic thin film from the first end to the second end of the wire, and the second insulating layer 122 may be obtained by winding an organic thin film from the second end to the first end of the wire, that is, the winding direction of the first insulating layer 121 may be different from the winding direction of the second insulating layer 122. As another example, the winding angle of the first insulating layer 121 and the second insulating layer 122 may be different. As long as the winding paths of the first insulating layer 121 and the second insulating layer 122 are different, the specific winding manner of the first insulating layer 121 and the second insulating layer 122 is not limited here.

In the manufacturing process of the inductor, the coil and the magnetic core material are required to be placed in a mold, and the coil and the magnetic core material are integrally formed by adopting a pressing process. If only the first insulating layer 121 is disposed on the surface of the wire and the second insulating layer 122 is not disposed, the magnetic powder easily enters the surface of the wire through the edge of the first insulating layer 121 under the action of pressure in the pressing process, thereby affecting the insulating performance of the wire and the magnetic powder in the magnetic core. In this embodiment of the present application, the winding path of the first insulating layer 121 is different from the winding path of the second insulating layer 122, so that the second insulating layer 122 can press the edge of the first insulating layer 121, and thus, in the pressing process, the magnetic powder is not easy to enter the surface of the wire through the edge of the first insulating layer 121, so that the insulating performance between the wire and the magnetic powder in the magnetic core is improved, and the voltage withstanding performance of the inductor is further improved. In addition, the manufacturing process of the second insulating layer 122 is similar to that of the first insulating layer 121, and adding the second insulating layer 122 does not increase the process cost, so that mass production is facilitated.

In one possible implementation, the materials of the first insulating layer 121 and the second insulating layer 122 may include, but are not limited to, low water absorbent resin materials such as Polyimide (PI), polyamide 6T resin (Polyamide 6T, PA 6T), polyamide9T resin (Polyamide 9T, PA 9T), polyphenylene sulfide (Polyphenylene sulfide, PPS), polyethylene terephthalate (Polyethylene terephthalate, PET), polyoxyxylylene (Polyphenylene oxide, PPE), polyethylene (PE), polyetherimide (polyether imide, PEI), polyoxymethylene (POM), polyamide 12 resin (Polyamide 12, PA 12), polysulfone (Polysulfone, PSU), polyetheretherketone (Polyether ether ketone, PEEK), and the like, and modified materials thereof. The thickness of the first insulating layer 121 may be in the range of 0.003mm to 0.1mm, for example, the thickness of the first insulating layer 121 may be 0.003mm, 0.05mm, or 0.1mm. The thickness of the second insulating layer 122 may be in the range of 0.003mm to 0.1mm, for example, the thickness of the second insulating layer 122 may be 0.003mm, 0.05mm, or 0.1mm. The total thickness of the composite insulation layer 12 may be in the range of 0.05mm to 0.30mm, for example, the total thickness of the composite insulation layer 12 may be 0.05mm, 0.2mm, or 0.30mm.

Through testing, the inductor in the first implementation mode can bear withstand voltage tests that alternating voltage is larger than 1000V, current is smaller than 0.5mA and 10s, and therefore, the working voltage of the inductor can be increased to be higher than 1000V by adopting the composite insulating layer in the first implementation mode.

The implementation mode II is as follows:

fig. 5 is another schematic structural diagram of the coil in the embodiment of the present application, and referring to fig. 2 and 5, the first insulating layer 121 is a strip-shaped organic film, and the first insulating layer 121 is tightly wound on the surface of the wire (the wire is wrapped by the first insulating layer 121 in fig. 5, and the wire is not shown). The second insulating layer 122 may include: the second insulating layer 122 is hollow and tubular, and the second insulating layer 122 is sleeved on the surface of the first insulating layer 121. In fig. 5, the second insulating layer is not shown in order to clearly illustrate the structure of the first insulating layer 121.

The first insulating layer 121 is made of an organic thin film, which has good insulating properties but poor mechanical properties. The second insulating layer 122 is made of a resin material, the mechanical property of the cured resin material is good, the second insulating layer 122 has certain hardness, and the second insulating layer 122 is arranged on the outer side of the first insulating layer 121, so that the coil can be protected and prevented from deforming in the pressing process. In the second implementation mode, the composite insulating layer 12 of the organic film and the resin material is arranged in the coil, so that the inductor has good mechanical property on the basis of good insulating property, and the reliability of the inductor is improved.

In the manufacturing process, the strip-shaped organic thin film may be manufactured using an organic material, and then the strip-shaped organic thin film is wound around the surface of the wire in turns, resulting in the first insulating layer 121 wrapping the wire. The material of the first insulating layer 121 may include, but is not limited to, PI, PA6T, PA9T, PPS, PET, PPE, PE, PEI, POM, PA, PSU, PEEK, and other low water absorbent resin materials and modified materials thereof. The thickness of the first insulating layer 121 may be in the range of 0.003mm to 0.1mm, for example, the thickness of the first insulating layer 121 may be 0.003mm, 0.05mm, or 0.1mm.

In one possible implementation, the material of the second insulating layer 122 may include a resin material such as polyphenylene sulfide. The resin material melted into a liquid state may be extruded onto the surface of the first insulating layer 121, and cooled to form the second insulating layer 122 surrounding the first insulating layer 121. The thickness of the second insulating layer 122 obtained by this manufacturing method may be in the range of 0.05mm to 0.3mm, preferably in the range of 0.1mm to 0.25mm, and for example, the thickness of the second insulating layer 122 may be 0.05mm, 0.1mm, 0.2mm, 0.25mm or 0.3mm.

In another possible implementation, the material of the second insulating layer 122 may include a resin material such as epoxy. A second insulating layer may be formed on the surface of the first insulating layer 121 by powder spraying. The thickness of the second insulating layer 122 obtained by the manufacturing method may be in the range of 0.2mm to 0.25mm, for example, the thickness of the second insulating layer 122 may be 0.2mm, 0.22mm, or 0.25mm.

The total thickness of the composite insulation layer 12 may be in the range of 0.05mm to 0.30mm, for example, the total thickness of the composite insulation layer 12 may be 0.05mm, 0.2mm, or 0.30mm.

Through testing, the inductor in the second implementation mode can bear withstand voltage tests that alternating voltage is larger than 300V, current is smaller than 0.5mA and 10s, and therefore, the working voltage of the inductor can be raised to be higher than 300V by adopting the composite insulating layer in the second implementation mode.

And the implementation mode is three:

referring to fig. 2, the first insulating layer 121 may be a paint film, for example, a material of which may include unsaturated polyester imide or polyimide, or the like. The first insulating layer 121 is hollow and tubular, and the first insulating layer 121 is sleeved on the surface of the wire. The second insulating layer 122 may include: the second insulating layer 122 is hollow and tubular, and the second insulating layer 122 is sleeved on the surface of the first insulating layer 121.

The first insulating layer 121 is a paint film, which has poor mechanical properties and is easily thinned by pressure during the pressing process. The second insulating layer 122 is made of a resin material, the mechanical property of the cured resin material is good, the second insulating layer 122 has certain hardness, and the second insulating layer 122 is arranged on the outer side of the first insulating layer 121, so that the coil can be protected and prevented from deforming in the pressing process.

In the manufacturing process, the paint can be made into liquid impregnating varnish, the wire is put into the impregnating varnish, and vacuum pressure impregnation is adopted until the surface of the wire forms a complete paint film, namely, the first insulating layer 121 is formed on the surface of the wire 11. The thickness of the first insulating layer 121 may be in the range of 0.05mm to 0.2mm, for example, the thickness of the first insulating layer 121 may be 0.05mm, 0.1mm, or 0.2mm.

Through testing, the inductor in the third implementation mode can bear withstand voltage tests that alternating voltage is larger than 300V, current is smaller than 0.5mA and 10s, and therefore, the working voltage of the inductor can be raised to be higher than 300V by adopting the composite insulating layer in the third implementation mode.

The implementation mode is four:

fig. 6 is another schematic structural view of the coil in the embodiment of the present application, and in combination with fig. 2 and 6, the first insulating layer 121 is a paint film, for example, the material of the paint film may include unsaturated polyester imide or polyimide, or the like. The first insulating layer 121 is hollow and tubular, and the first insulating layer 121 is sleeved on the surface of the wire (the wire is wrapped by the first insulating layer 121 in fig. 6, and the wire is not shown). The second insulating layer 122 is a strip-shaped organic film, and the second insulating layer 122 is tightly wound around the surface of the first insulating layer 121.

The first insulating layer 121 is a paint film, which has poor mechanical properties and is easily thinned by pressure during the pressing process. The second insulating layer 122 is an organic film, the mechanical property of the organic film is good, and the second insulating layer 122 is arranged on the outer side of the first insulating layer 121, so that the coil can be protected and prevented from being deformed in the pressing process.

In the manufacturing process, the paint can be made into liquid impregnating varnish, the wire is put into the impregnating varnish, and vacuum pressure impregnation is adopted until the surface of the wire forms a complete paint film, namely, the first insulating layer 121 is formed on the surface of the wire 11. Then, the strip-shaped organic film is wound around the surface of the first insulating layer 121 in turns, to obtain the second insulating layer 122 wrapping the first insulating layer 121.

In one possible implementation, the thickness of the first insulating layer 121 may be in the range of 0.05mm to 0.2mm, for example, the thickness of the first insulating layer 121 may be 0.05mm, 0.1mm, or 0.2mm. The thickness of the second insulating layer is in the range of 0.003mm to 0.1mm, for example, the thickness of the second insulating layer 122 may be 0.003mm, 0.05mm, or 0.1mm. The material of the second insulating layer 122 may include, but is not limited to, PI, PA6T, PA9T, PPS, PET, PPE, PE, PEI, POM, PA, PSU, PEEK, and other low water absorbent resin materials and modified materials thereof.

Through testing, the inductor in the fourth implementation mode can bear withstand voltage tests that alternating voltage is larger than 300V, current is smaller than 0.5mA and 10s, and therefore, the working voltage of the inductor can be raised to be higher than 300V by adopting the composite insulating layer in the fourth implementation mode.

The implementation mode is five:

referring to fig. 2 and 5, the first insulating layer 121 is a strip-shaped organic film, and the first insulating layer 121 is tightly wound around the surface of the wire (the wire is wrapped with the first insulating layer 121 in fig. 5, the wire is not shown). The second insulating layer 122 is a paint film, the second insulating layer 122 is hollow and tubular, and the second insulating layer 122 is sleeved on the surface of the first insulating layer 121. In fig. 5, the second insulating layer is not shown in order to clearly illustrate the structure of the first insulating layer 121.

The material of the second insulating layer 122 may include unsaturated polyester imide or polyimide, or the like. In the manufacturing process, the paint can be made into liquid impregnating varnish, the wire wrapped with the first insulating layer 121 is put into the impregnating varnish, and vacuum pressure impregnation is adopted until the surface of the first insulating layer 121 forms a paint film with complete appearance, namely, the second insulating layer 122 is formed on the surface of the first insulating layer 121. The thickness of the second insulating layer 122 may be in the range of 0.05mm to 0.2mm, for example, the thickness of the second insulating layer 122 may be 0.05mm, 0.1mm, or 0.2mm.

Through testing, the inductor in the fifth implementation mode can bear withstand voltage tests that alternating voltage is larger than 300V, current is smaller than 0.5mA and 10s, and therefore, the working voltage of the inductor can be raised to be higher than 300V by adopting the composite insulating layer in the fifth implementation mode.

The above describes various implementation manners of the composite insulating layer in the embodiment of the present application, in order to further improve the insulating performance of the magnetic powder in the wire and the magnetic core, the inductor in the embodiment of the present application may further include: the insulating protector is described in detail below with reference to the accompanying drawings.

Fig. 7 is another schematic structural diagram of an inductor according to an embodiment of the present application, as shown in fig. 7, where the inductor may further include: insulation protector 300, a portion of coil 100 except for an end is located in insulation protector 300, and magnetic core 200 wraps insulation protector 300. In this way, the insulation performance between the wires in the coil 100 and the magnetic powder in the magnetic core 200 can be further improved, thereby further improving the withstand voltage performance of the inductor. Also, the insulation protector 300 may function to protect the coil 100, improving structural reliability of the inductor.

In some embodiments of the present application, with continued reference to fig. 7, the insulating protector 300 described above may include: the bottom shell 31 and upper cover 32, bottom shell 31 is equipped with first recess, and upper cover 32 is equipped with the second recess. The first groove and the second groove may form a receiving space for receiving the coil 100 and two through holes U connected with the receiving space, the coil 100 is located in the receiving space, and two ends of the coil 100 respectively pass through the two through holes U. In addition, the gap between the coil 100 and the insulation protector 300 is filled with a resin material, so that the position of the coil 100 is more fixed, and the structural reliability of the inductor is improved. In specific implementations, the material of the bottom case 31 (or the upper cover 32) may include glass fiber, carbon fiber, etc., or the material of the bottom case 31 (or the upper cover 32) may include, but is not limited to, PI, PA6T, PA9T, PPS, PET, PPE, PE, PEI, POM, PA, PSU, PEEK, etc. low water absorbent resin materials and modified materials thereof. The thickness of the bottom case 31 (or the upper cover 32) may be in the range of 0.1mm to 0.25mm, for example, the thickness of the bottom case 31 (or the upper cover 32) may be 0.1mm, 0.2mm, or 0.25mm.

Fig. 8 is a schematic diagram of an installation process of an insulation protector according to an embodiment of the present application, wherein (1) in fig. 8 is a schematic diagram of a structure of a manufactured coil 100, (2) in fig. 8 is a schematic diagram of a bottom case 31, the bottom case 31 has a first groove 311, (3) in fig. 8 is a schematic diagram of a structure of an upper cover 32, and (4) in fig. 8 is a schematic diagram of a structure after the insulation protector 300 is installed. As shown in fig. 8, during the installation of the insulation protector 300, the coil 100 may be first placed in the first recess 311 of the bottom case 31, and then the upper cover 32 is fastened to the bottom case 31, to obtain the structure shown in (4) of fig. 8. Then, a resin material is injected into a gap between the insulating protector 300 and the coil 100.

Fig. 9 is another schematic structural diagram of an inductor according to an embodiment of the present application, as shown in fig. 9, and in other embodiments of the present application, the insulating protector 300 may be insulating paper, and the insulating paper wraps the portion of the coil 100 except for the end portion. In the manufacturing process, the insulating paper may be uniformly wound around the surface of the coil 100. In particular implementations, the insulating paper may include, but is not limited to, aramid paper, DMD paper, green shell paper, fiberglass paper, and the like. The thickness of the insulating paper may be in the range of 0.05mm to 0.13mm, for example, the thickness of the insulating paper may be 0.05mm, 0.08mm or 0.13mm.

In the structures shown in fig. 7 and 9, the coil 100 may be any one of the above-described implementations one to five, that is, the surface of the wire in the coil 100 may be wrapped with a composite insulating layer. Through tests, the inductor shown in fig. 7 and 9 can bear withstand voltage tests that alternating voltage is greater than 800V, current is less than 0.5mA and 10s, and therefore, the working voltage of the inductor can be increased to be more than 800V through the arrangement of the insulating protection piece.

Based on the same technical concept, the embodiments of the present application also provide another inductor, referring to fig. 7 and 9, the inductor may include: coil 100, insulating protector 300 and magnetic core 200, the part except for the end of coil 100 is located in insulating protector 300, and magnetic core 200 wraps insulating protector 300. Wherein the coil 100 may include: a wire, and an insulating layer surrounding the wire.

Similarly to the above embodiment, by providing the insulating protector 300, the insulating protector 300 can perform insulating and protecting functions, and the withstand voltage performance and the structural reliability of the inductor can be further improved. The specific implementation manner of the insulating protection member in this embodiment may be implemented with reference to the foregoing embodiments, and the repetition is not repeated.

The difference from the above embodiment is that: in this embodiment, the coil 100 may be any one of the above-mentioned implementation one to implementation five, that is, the surface of the wire in the coil 100 may be wrapped with a composite insulating layer; alternatively, a single insulating layer may be provided on the surface of the wire in the coil 100, and for example, the coil 100 may be any one of a film-covered wire, an enamel-covered wire, and a plastic-covered wire.

Illustratively, the insulating layer may include: the resin material may be, for example, polyphenylene sulfide resin. The insulating layer is hollow tubular, and the insulating layer cover is located the surface of wire. The thickness of the insulating layer may be between 0.1mm and 0.25mm, for example, the thickness of the insulating layer may be 0.1mm, 0.22mm or 0.25mm. The insulating layer is made of resin materials, so that a thicker insulating layer can be obtained, and the insulating performance and the mechanical performance of the insulating layer are better, so that the voltage resistance of the inductor is better. Through testing, the inductor can bear withstand voltage tests of alternating voltage greater than 1000V and current less than 0.5mA and 10 s.

In practical applications, the structure and material of the insulating layer on the surface of the wire in the coil can be determined by the coil at the pins of the inductor. And, whether the inductor includes the insulation protector can be judged by cutting the inductor and analyzing the cross-sectional structure.

Based on the same technical concept, the embodiment of the application also provides a power control device, which may include: any one of the inductors, and a power conversion circuit, wherein the power conversion circuit is electrically connected with the inductor and is used for converting alternating current and direct current. Since the inductor is excellent in withstand voltage performance and reliability, the power control device including any of the above inductors is also excellent in performance.

While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present application without departing from the spirit and scope of the embodiments of the present application. Thus, if such modifications and variations of the embodiments of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to encompass such modifications and variations.

Claims

1. An inductor, comprising: a coil, and a magnetic core surrounding the coil;

the coil includes: a wire, and a composite insulating layer surrounding the wire;

the composite insulating layer comprises at least: a first insulating layer and a second insulating layer;

the first insulating layer is wrapped on the surface of the wire, and the second insulating layer is wrapped on the surface of the first insulating layer;

the first insulating layer is different from the second insulating layer in material or structure.

2. The inductor of claim 1, wherein the first insulating layer and the second insulating layer are each a stripe-shaped organic film;

the first insulating layer is tightly wound on the surface of the wire, and the second insulating layer is tightly wound on the surface of the first insulating layer;

the winding path of the first insulating layer is different from the winding path of the second insulating layer.

3. The inductor of claim 2, wherein the first insulating layer has a thickness in the range of 0.003mm to 0.1mm and the second insulating layer has a thickness in the range of 0.003mm to 0.1 mm.

4. The inductor of claim 1, wherein the first insulating layer is a strip-shaped organic film, and the first insulating layer is tightly wound on the surface of the wire;

The second insulating layer includes: a resin material;

the second insulating layer is hollow and tubular, and the second insulating layer is sleeved on the surface of the first insulating layer.

5. The inductor of claim 4, wherein a thickness of the first insulating layer is in a range of 0.003mm to 0.1mm and a thickness of the second insulating layer is in a range of 0.05mm to 0.3 mm.

6. The inductor of claim 1 wherein said first insulating layer is a paint film, said first insulating layer is hollow tubular, said first insulating layer is sleeved on a surface of said wire;

the second insulating layer includes: a resin material;

7. The inductor of claim 6, wherein a thickness of the first insulating layer is in a range of 0.05mm to 0.2mm and a thickness of the second insulating layer is in a range of 0.05mm to 0.3 mm.

8. The inductor of claim 1 wherein said first insulating layer is a paint film, said first insulating layer is hollow tubular, said first insulating layer is sleeved on a surface of said wire;

The second insulating layer is a strip-shaped organic film and is tightly wound on the surface of the first insulating layer.

9. The inductor of claim 8, wherein the first insulating layer has a thickness in the range of 0.05mm to 0.2mm and the second insulating layer has a thickness in the range of 0.003mm to 0.1 mm.

10. The inductor of claim 1, wherein the first insulating layer is a strip-shaped organic film, and the first insulating layer is tightly wound on the surface of the wire;

the second insulating layer is a paint film, the second insulating layer is hollow and tubular, and the second insulating layer is sleeved on the surface of the first insulating layer.

11. The inductor of claim 10, wherein the first insulating layer has a thickness in the range of 0.003mm to 0.1mm and the second insulating layer has a thickness in the range of 0.05mm to 0.2 mm.

12. An inductor according to any one of claims 1 to 11, wherein the thickness of the composite insulating layer is in the range 0.05mm to 0.3 mm.

13. The inductor as claimed in any one of claims 1 to 12, further comprising: an insulating protector;

the part of the coil except the end part is positioned in the insulating protection piece;

The magnetic core wraps the insulating protection member.

14. The inductor of claim 13, wherein the insulating protector comprises: a bottom case and an upper cover;

the bottom shell is provided with a first groove, and the upper cover is provided with a second groove;

the first groove and the second groove form a containing space for containing the coil and two through holes connected with the containing space;

the coil is positioned in the accommodating space, and two end parts of the coil respectively pass through the two through holes;

and a resin material is filled in a gap between the coil and the insulating protection piece.

15. The inductor of claim 13 wherein said insulating protector is insulating paper;

the insulating paper wraps the portion of the coil except for the end portion.

16. An inductor, comprising: a coil, an insulating protector, and a magnetic core;

the magnetic core wraps the insulating protection piece;

the coil includes: a wire, and an insulating layer surrounding the wire.

17. The inductor of claim 16, wherein the insulating layer comprises: a resin material;

The insulating layer is hollow tubular, and the insulating layer is sleeved on the surface of the wire.

18. The inductor of claim 17, wherein the insulating layer has a thickness between 0.1mm and 0.25 mm.

19. A power control apparatus, comprising: an inductor according to any one of claims 1 to 18, and a power conversion circuit electrically connected to the inductor, the power conversion circuit being for ac to dc conversion.