EP4654233A1

EP4654233A1 - Transformer and manufacturing method therefor

Info

Publication number: EP4654233A1
Application number: EP24744781.6A
Authority: EP
Inventors: Seohyun Lee; Jung Wook Sim; Yoon Sun Lee; Seung Pil Yang
Original assignee: LS Electric Co Ltd
Current assignee: LS Electric Co Ltd
Priority date: 2023-01-20
Filing date: 2024-01-08
Publication date: 2025-11-26
Also published as: CN120476457A; WO2024155000A1

Abstract

A transformer and a manufacturing method therefor are disclosed. A transformer according to an aspect of the present invention comprises: a housing having a housing space formed therein; a first winding unit connected to an external power source or a load to conduct electricity and accommodated in the housing space; a shield unit accommodated in the housing space to be spaced apart from the first winding unit, and connected to ground to conduct electricity; and a semiconductive layer formed to partially cover a surface surrounding the housing space, wherein the semiconductive layer is formed to have an area smaller, by a preset ratio, than the total area of the surface surrounding the housing space, the shield unit is positioned to be in contact with the semiconductive layer in the housing space, and the semiconductive layers respectively formed on the plurality of surfaces surrounding the housing space are continuous with each other and may be in contact with the shield unit to conduct electricity.

Description

TECHNICAL FIELD

The present invention relates to a transformer and a manufacturing method therefor, and more particularly, to a transformer and a manufacturing method therefor capable of alleviating electric field concentration and partial discharge.

BACKGROUND

A transformer refers to a device that converts a high-voltage or low-voltage current into a low-voltage or high-voltage current. Transformers are commonly used to convert alternating current (AC) voltage.
Transformers may be classified into low-frequency transformers, medium-frequency transformers, and high-frequency transformers according to the frequency of the current conducted therethrough. In particular, a high-frequency transformer may be defined as a transformer having an operating frequency exceeding a medium frequency (10 kHz).
A high-frequency transformer may be provided in various types of devices requiring high-frequency power, such as high-frequency switching power supplies, high-frequency inverter power supplies, and high-frequency inverter welders.
At this time, as the capacity of the high-frequency transformer increases, high-voltage electricity may be conducted through the high-frequency transformer. Accordingly, there is a risk that components of the high-frequency transformer may be damaged by the electricity conducted therethrough.
Therefore, in order to increase the capacity of a high-frequency transformer, measures to enhance electrical insulation and alleviate the electric field must be accompanied.
At this time, if the volume of the configuration for enhancing electrical insulation and alleviating the electric field is excessive, the overall size of the high-frequency transformer increases, making it difficult to apply to the above-described various devices. In addition, if the configuration is excessively expensive, the manufacturing cost of the high-frequency transformer increases, making it difficult to secure marketability.
Korean Registered Patent No. 10-2460560 discloses a high-voltage high-frequency insulation transformer with an electric field flattening shield. Specifically, it discloses a high-voltage high-frequency insulation transformer capable of preventing local partial discharge and optimizing the insulation distance by including an electric field flattening means between a high-voltage winding wound around a core and the core. The electric field flattening means is provided in the form of a sheet and is installed to cover a portion of the core that faces the high-voltage winding.
However, the electric field flattening shield disclosed in the prior art document is provided as a separate component and has a structure in which it is coupled to the core. The prior art document does not disclose means for coupling the electric field flattening shield to the core or measures for maintaining the position of the coupled electric field flattening shield.
Therefore, while the prior art document provides a measure for achieving electric field flattening between the core and the high-voltage winding, it fails to provide a solution for easily coupling the electric field flattening shield to the high-frequency transformer while maintaining its function during actual manufacturing.
Korean Registered Patent No. 10-1732116 discloses a high-voltage, high-frequency, high-power transformer. Specifically, it discloses a high-voltage, high-frequency, high-power transformer in which a primary winding and a magnetic core assembly are mounted inside a hollow tubular body that forms a part of an insulating structure, and a secondary winding is disposed on the outside of the hollow tubular body to achieve electrical insulation and cooling.
However, the high-voltage, high-frequency, high-power transformer disclosed in the prior art document is configured such that the insulating structure, together with the primary winding, secondary winding, and magnetic core assembly, forms the outer shape of the transformer. That is, the insulating structure proposed in the prior art inevitably leads to an increase in the overall volume of the transformer.
Korean Patent Laid-Open Publication No. 10-2022-0144955 discloses an oil-immersed high-frequency transformer and a manufacturing method therefor. Specifically, it discloses an oil-immersed high-frequency transformer and its manufacturing method, in which a transformer main body, bushings, and the like are coupled to an enclosure, and insulating oil is filled to achieve insulation.
However, the oil-immersed high-frequency transformer and its manufacturing method disclosed in the prior art document are based on the premise that the transformer main body, bushings, and the like have already been manufactured, and only disclose a method for connecting them to an enclosure. That is, the prior art document does not provide a solution for adding a configuration to maintain insulation during the manufacturing process of the transformer main body, bushings, and the like.

Korean Registered Patent No. 10-2460560 (2022. 10. 25. )
Korean Registered Patent No. 10-1732116 (2017. 04. 25. )
Korean Patent Laid-Open Publication No. 10-2022-0144955 (2022. 10. 28 .)

DISCLOSURE

TECHNICAL PROBLEM

The present invention is to solve the above problems, and the present invention is directed to providing a transformer and a method for manufacturing the same, having a structure capable of mitigating electric field concentration and partial discharge.
The present invention is also directed to providing a transformer and a method for manufacturing the same, having a structure in which a member for mitigating electric field concentration and partial discharge is not damaged by external environmental factors.
The present invention is also directed to providing a transformer and a method for manufacturing the same, having a structure capable of mitigating electric field concentration and partial discharge in various forms.
The present invention is also directed to providing a transformer and a method for manufacturing the same, having a structure capable of preventing electric field breakdown or electric field concentration caused by a member for mitigating electric field concentration and partial discharge.
The present invention is also directed to providing a transformer and a method for manufacturing the same, having a structure that ensures design flexibility.
The problems of the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

TECHNICAL SOLUTION

According to an aspect of the present invention, provided is a transformer comprising: a housing with a housing space formed therein; a first winding unit which is electrically connectable to an external power source or load and is accommodated in the housing space; a shield unit which is accommodated in the housing space spaced apart from the first winding unit and is electrically connectable to ground; and a semiconductive layer partially covering a surface surrounding the housing space, wherein the semiconductive layer is formed to have an area smaller than a predetermined ratio of an entire area of the surface surrounding the housing space, and wherein the shield unit is positioned in contact with the semiconductive layer in the housing space, and the semiconductive layers respectively formed on a plurality of the surfaces surrounding the housing space are continuous with each other and are electrically connectable to the shield unit.
In this case, a transformer may be provided in which the transformer further includes a bushing coupled to the housing and having a bushing space formed therein that is in fluid communication with the housing space,
the shield unit includes a bushing shield member positioned in the bushing space and electrically connectable to the ground; and a housing shield member coupled to the surface surrounding the housing space and electrically connectable to the bushing shield member.
In addition, a transformer may be provided in which the semiconductive layer is further formed on an inner surface of the bushing that surrounds the bushing space, such that the semiconductive layer is continuous with the semiconductive layer formed on the surface surrounding the housing space, and the bushing shield member extends in one direction in which the bushing extends, such that one end of the bushing shield member in the extending direction is positioned to overlap the inner surface of the bushing, and the other end in the extending direction is positioned to be spaced apart from the semiconductive layer.
In this case, a transformer may be provided in which the semiconductive layer is further formed on an inner surface of the bushing that surrounds the bushing space, such that the semiconductive layer is continuous with the semiconductive layer formed on the surface surrounding the housing space, the bushing shield member extends in one direction in which the bushing extends, and a point between both ends of the bushing shield member in the extending direction is electrically connectable to the ground, and the semiconductive layer is formed such that a boundary thereof is located between one end of the bushing shield member, which faces away from the housing, and the point.
In addition, a transformer may be provided in which the housing includes a first housing inner surface configured to support the first winding unit; a second housing inner surface and a third housing inner surface, each extending in one direction, continuously connected to the first housing inner surface, and disposed to face each other with the housing space interposed therebetween; and a fourth housing inner surface and a fifth housing inner surface, each extending in another direction, continuously connected to the first to third housing inner surfaces, and disposed to face each other with the housing space interposed therebetween,
and the semiconductive layer is formed to at least partially cover each of the first to fifth housing inner surfaces.
In this case, a transformer may be provided in which an area of the semiconductive layer formed on the first housing inner surface is equal to or less than an area of the first housing inner surface, and an area of the semiconductive layer formed on the second to fifth housing inner surfaces is less than a sum of areas of the second to fifth housing inner surfaces.
In addition, a transformer may be provided in which the housing shield member extends along the second to fifth housing inner surfaces so as to surround the housing space, and is spaced apart by a predetermined distance from one end, opposite to the first housing inner surface, among ends in a height direction of the second to fifth housing inner surfaces, and the semiconductive layer is formed from the housing shield member to the first housing inner surface.
In this case, a transformer may be provided in which a total area of the semiconductive layer formed on the first to fifth housing inner surfaces is less than 90% of a total area of the first to fifth housing inner surfaces.
In addition, a transformer may be provided in which the housing includes a bobbin support portion that extends in a height direction from the first housing inner surface and is spaced apart from the second to fifth housing inner surfaces; and a core receiving portion that is formed to penetrate the bobbin support portion and receives a core unit, while fluid communication with the housing space is blocked, and the first winding unit includes a first bobbin in which a first bobbin space is formed to penetrate the first bobbin and be coupled to the bobbin support portion; and a first coil wound around the first bobbin and electrically connectable to an external power source or load.
In this case, a transformer may be provided in which the semiconductive layer is formed to cover a surface of the bobbin support portion that faces the housing space, a surface area of the semiconductive layer formed on the surface of the bobbin support portion is equal to or less than a surface area of the surface of the bobbin support portion, and the housing shield member is disposed on the surface of the bobbin support portion to be in contact with the semiconductive layer.
In addition, a transformer may be provided in which the housing shield member extends along the surface of the bobbin support portion to surround the core receiving portion, and is spaced apart by a predetermined distance from one end of the surface of the bobbin support portion in a height direction, the one end being opposite to the first housing inner surface, and the semiconductive layer is formed on the surface of the bobbin support portion from the housing shield member to the first housing inner surface.
In addition, according to an aspect of the present invention, provided is a transformer comprising: a housing with a housing space formed therein; a bushing coupled to the housing and having a bushing space formed therein, the bushing space being in fluid communication with the housing space;
a shield unit accommodated in the bushing space and electrically connectable to ground; and a semiconductive layer formed to at least partially cover a surface surrounding the housing space and a surface surrounding the bushing space, respectively, wherein the semiconductive layer is formed to cover the entire surface surrounding the housing space, and to cover a portion of the surface surrounding the bushing space that is in contact with the shield unit, such that the semiconductive layer is in contact with the shield unit.
In this case, a transformer may be provided in which a portion of the semiconductive layer that covers the surface surrounding the bushing space and a portion that covers the surface surrounding the housing space are continuous with each other.
In addition, a transformer may be provided in which the housing includes a bobbin support portion disposed in the housing space and extending in a height direction from a surface that surrounds the housing space on one side in the height direction, and the semiconductive layer is formed to entirely cover a surface of the bobbin support portion that faces the housing space.

ADVANTAGEOUS EFFECT

According to the above configuration, the transformer and the method for manufacturing the same according to an embodiment of the present invention can mitigate electric field concentration and partial discharge.
The transformer includes a first winding unit electrically connectable to an external power source or load. The first winding unit is accommodated in a housing space formed inside a housing that defines the outer shape of the transformer. A core unit is inserted through the housing and the first winding unit accommodated in the housing, thereby allowing an induced current to be generated and a voltage transformation process to be performed.
A shield unit is provided in the housing space. The shield unit includes a bushing shield member provided in a bushing coupled to the housing, and a housing shield member provided in the housing space and electrically connectable to the bushing shield member. The bushing shield member and the housing shield member may be formed of a conductive material, such as aluminum.
A semiconductive layer is formed on the surface of the housing surrounding the housing space or on the surface of the bushing surrounding the bushing space formed inside the bushing. The semiconductive layer is formed of a semiconductive material and is in contact with the shield unit, thereby being electrically connectable to the shield unit.
The housing shield member is disposed to be spaced apart from the first winding unit and to surround the first winding unit from the outside. A portion of the semiconductive layer supports the first winding unit, and another portion is spaced apart from the first winding unit and disposed to surround the first winding unit from the outside.
Accordingly, the electric field generated from the first winding unit can be sufficiently mitigated, sufficient insulation performance can be secured, and partial discharge can be prevented.
In addition, according to the above configuration, the transformer and the manufacturing method thereof according to an embodiment of the present invention can prevent the member for mitigating electric field concentration and partial discharge from being damaged by external environmental factors.
As described above, the first winding unit is accommodated in the housing space and is not exposed to the outside. Likewise, the shield unit and the semiconductive layer, which are provided to mitigate the electric field generated from the first winding unit, are also accommodated in the housing space and are not exposed to the outside.
In an embodiment, the housing may include a first housing and a second housing. The housing space may be partially formed in each of the first housing and the second housing, and when the first housing and the second housing are coupled, the housing space is sealed, thereby blocking fluid communication with the outside.
Accordingly, the shield unit and the semiconductive layer accommodated in the housing space may mitigate the electric field generated by the first winding unit without being affected by external environmental conditions. As a result, damage to the shield unit and the semiconductive layer due to the external environment can be prevented.
In addition, according to the above configuration, the transformer and the method for manufacturing the same according to an embodiment of the present invention can mitigate electric field concentration and partial discharge in various forms.
The shield unit includes a bushing shield member provided in the bushing and a housing shield member provided in the housing. The bushing shield member is electrically connectable to the housing shield member and to an external ground.
The shield unit is disposed to be at least partially in contact with the semiconductive layer. In an embodiment, the housing shield member is disposed to be in contact with the semiconductive layer formed on the housing inner surface that surrounds the housing space. In addition, the bushing shield member is disposed to be in contact with the semiconductive layer formed on the inner surface of the bushing that surrounds the bushing space.
That is, the electric field generated by the first winding unit can be mitigated by both the shield unit and the semiconductive layer.
Accordingly, the generated electric field can be mitigated in various ways, thereby sufficiently reducing the electric field and ensuring sufficient insulation performance.
In addition, according to the above configuration, the transformer and the method for manufacturing the same according to an embodiment of the present invention can prevent electric field breakdown or electric field concentration caused by the member for mitigating electric field concentration and partial discharge.
In an embodiment, the semiconductive layer may also be formed on an inner surface of the bushing body that surrounds the bushing space in which the bushing shield member is accommodated. In this case, the semiconductive layer may be formed to overlap and come into contact with a portion of the bushing shield member, while being spaced apart from and not in contact with another portion of the bushing shield member.
Specifically, the bushing shield member may extend along the extending direction of the bushing. The semiconductive layer may be in contact with one end of the bushing shield member in the extending direction-namely, the end facing the housing-while being spaced apart from the other end opposite to the housing.
Specifically, a portion of the bushing shield member is electrically connected to an external ground. The semiconductive layer may be formed to be spaced apart from the portion. In other words, a boundary of the semiconductive layer may be located between the portion and the one end of the bushing shield member.
Accordingly, since the semiconductive layer is not directly electrically connected to the external ground, electric field breakdown or electric field concentration can be prevented.
In addition, with the above configuration, the transformer and the method for manufacturing the same according to an embodiment of the present invention can ensure design flexibility.
The semiconductive layer may be formed to have an area corresponding to a predetermined ratio of the total area of the inner surface of the housing that surrounds the housing space. In other words, the semiconductive layer may be partially formed on the inner surface of the housing. In an embodiment, the semiconductive layer may be formed to have an area less than 90% of the total area of the inner surface of the housing.
In an embodiment, the semiconductive layer may also be formed on a surface of a bobbin support portion that supports the first winding unit. The semiconductive layer may be formed on a surface of the bobbin support portion that faces the housing space and may have an area smaller than that of the surface. In an embodiment, the semiconductive layer formed on the surface of the bobbin support portion may be formed to have an area equal to or less than the area of the surface of the bobbin support portion.
In any case, it is sufficient if the total area of the semiconductive layer is maintained to be less than 90% of the combined total area of the inner surface of the housing and the surface of the bobbin support portion.
In the above embodiment, the housing shield member may be disposed not only on the inner surface of the housing but also on the surface of the bobbin support portion. The housing shield members provided on the inner surface of the housing and the surface of the bobbin support portion may be electrically connected to each other and may also be electrically connected to an external ground through the bushing shield member.
That is, the semiconductive layer and the housing shield member may be formed in various configurations depending on the specifications of the transformer. Accordingly, the design flexibility of the transformer can be enhanced.
Advantageous effects of the present invention are not limited to the above-described effects, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a transformer according to an embodiment of the present invention.
FIG. 2 is a side view illustrating the transformer of FIG. 1.
FIG. 3 is an exploded perspective view illustrating the transformer of FIG. 1.
FIG. 4 is a cross-sectional perspective view taken along line A-A of the transformer of FIG. 1.
FIGS. 5 and 6 are cross-sectional perspective views taken along line B-B, illustrating a bushing and a housing provided in the transformer of FIG. 1.
FIG. 7 is a cross-sectional perspective view illustrating an embodiment in which a semiconductive layer and a shield ring are provided in the housing of FIGS. 5 and 6.
FIG. 8 is a cross-sectional perspective view illustrating another embodiment in which a semiconductive layer and a shield ring are provided in the housing of FIGS. 5 and 6.
FIG. 9 is a cross-sectional perspective view illustrating yet another embodiment in which a semiconductive layer and a shield ring are provided in the housing of FIGS. 5 and 6.
FIG. 10 is a side cross-sectional view illustrating an example of a shield member coupling portion for supporting the shield ring provided in the housing of FIGS. 5 and 6.
FIGS. 11 and 12 are cross-sectional perspective views illustrating other examples of shield member coupling portions for supporting the shield ring provided in the housing of FIGS. 5 and 6.
FIG. 13 is a cross-sectional perspective view illustrating yet another embodiment of the shield member coupling portion for supporting the shield ring provided in the housing of FIGS. 5 and 6.
FIG. 14 is an exploded perspective view illustrating the coupling relationship between the shield member coupling portion and the housing according to the embodiment of FIG. 13.
FIG. 15 is a side cross-sectional view illustrating the coupling relationship between the shield member coupling portion and the housing according to the embodiment of FIG. 13.
FIG. 16 is a perspective view illustrating an internal structure of a transformer according to another embodiment of the present invention.
FIG. 17 is a flowchart illustrating a flow of a manufacturing method of a transformer according to an embodiment of the present invention.
FIG. 18 is a flowchart illustrating detailed steps of step S100 in the manufacturing method of a transformer of FIG. 17.
FIG. 19 is an exemplary view illustrating a process of performing step S100 of FIG. 18.
FIG. 20 is a flowchart illustrating detailed steps of step S200 in the manufacturing method of a transformer of FIG. 17.
FIG. 21 is an exemplary view illustrating a process of performing step S200 of FIG. 20.
FIG. 22 is a flowchart illustrating detailed steps of step S300 in the manufacturing method of a transformer of FIG. 17.
FIGS. 23 and 24 are exemplary views illustrating a process of performing step S300 of FIG. 22.
FIG. 25 is a flowchart illustrating detailed steps of step S400 in the manufacturing method of a transformer of FIG. 17.
FIG. 26 is an exemplary view illustrating a process of performing step S400 of FIG. 25.
FIG. 27 is a flowchart illustrating detailed steps of step S500 in the manufacturing method of a transformer of FIG. 17.
FIG. 28 is an exemplary view illustrating a process of performing step S500 of FIG. 27.

MODES OF THE INVENTION

Hereinafter, exemplary embodiments of the present invention will be described in detail so that those of ordinary skill in the art can readily implement the present invention with reference to the accompanying drawings. The present invention may be embodied in many different forms and is not limited to the embodiments set forth herein. In the drawings, parts unrelated to the description are omitted for clarity of description of the present invention, and throughout the specification, same or similar reference numerals denote same elements.
The words and terms used in the present specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be construed as having meanings and concepts consistent with the technical spirit of the present invention, in accordance with the principle that an inventor may define terms and concepts to best describe their invention.
Accordingly, the embodiments described in the present specification and the configurations shown in the drawings correspond to preferred embodiments of the present invention, and do not represent all the technical spirit of the present invention, so the configurations may have various examples of equivalent and modification that can replace them at the time of filing the present invention.
In the following description, in order to clarify the features of the present invention, descriptions of some components may be omitted.

1. Term definition

The term "fluid communication" used in the following description refers to a state in which one or more members are connected so as to allow fluid flow between them. In an embodiment, the fluid communication may be established by members such as conduits, pipes, or tubes. In the following description, the term "fluid communication" may be used to mean that one or more members are "fluidly connected" to each other.
The term "electrical connection" used in the following description refers to a state in which one or more members are connected so as to allow the transmission of electric current or electrical signals between them, and may be variously referred to as "electrical connection," "energization," "energizable connection," "electrically connected state," "enabled current flow," "current-conducting state," or "electrical conduction." In an embodiment, the electrical connection may be established in a wired form using a wire member or the like, or in a wireless form using Bluetooth, Wi-Fi, RFID, or the like. In an embodiment, the electrical connection may include the meaning of "electrical communication."
The term "fluid" used in the following description refers to any form of material that flows by external force and whose shape or volume can be changed. In an embodiment, the fluid may be a liquid such as water or a gas such as air.
The terms "above or upper side", "below or lower side", "left side", "right side", "front side", and "rear side" used in the following description will be understood with reference to the coordinate system shown in the accompanying FIG. 1.

2. Description of the Configuration of Transformer 10 According to an Embodiment of the Present Invention

Referring to FIGS. 1 to 4, a transformer 10 according to an embodiment of the present invention is illustrated.
The transformer 10 according to an embodiment of the present invention may include a housing 100 that forms an outer shape thereof and is formed of an electrically insulating material. In addition, other components of the transformer 10 may be accommodated in the housing 100 and fixed by the electrically insulating material.
In addition, a semiconductive layer S.C may be formed on an inner surface of the transformer 10. The semiconductive layer S.C, together with a shield unit 500, may insulate the transformer 10 from the outside and alleviate electric field concentration and partial discharge phenomena occurring inside or outside the transformer 10.
The transformer 10 is electrically connectable to an external power source (not shown) and a load (not shown), respectively. Power supplied from the external power source (not shown) may be transformed by the transformer 10 and delivered to the load (not shown).
The transformer 10 may be provided in any form that is electrically connectable to an external power source (not shown) and a load (not shown), and is capable of transforming received power and delivering the transformed power. In this case, the transformer 10 may be implemented as a high-frequency transformer, a low-frequency transformer, or a medium-frequency transformer, depending on the frequency of the received power.
In the illustrated embodiment, the transformer 10 includes a housing 100, a core unit 200, a first winding unit 300, a second winding unit 400, a shield unit 500, a bushing 600, and a coupling frame 700.
In addition, referring to FIGS. 10 to 15, the transformer 10 further includes a shield member coupling portion 800. As will be described later, the shield member coupling portion 800 is configured to fix a housing shield member 520, which is a component of the shield unit 500, to the housing 100.
The housing 100 forms a part of the outer shape of the transformer 10. An internal space is formed in the housing 100 to accommodate other components of the transformer 10. In addition, other components of the transformer 10 may be coupled to and through the housing 100.
The housing 100 may be formed of an electrically insulating material. In addition, the housing 100 may be manufactured using a mold. In the above embodiment, the housing 100 may be manufactured by injecting the electrically insulating material into the mold.
In an embodiment, the electrically insulating material may be formed of a synthetic resin material such as epoxy or a silicon-based material. In another embodiment, the electrically insulating material may be formed of an insulating oil such as mineral oil, alkylbenzene, polybutene, alkylated naphthalene, alkylated diphenyl ethane, or silicon oil; a mixed oil of mineral oil and alkylbenzene; a vegetable oil such as natural ester; or a mixture thereof.
Accordingly, as will be described later, the material of the housing 100 and the substance filled in the housing space 110 may be formed of the same material.
The housing 100 is coupled to the core unit 200. An opening (i.e., a core receiving portion 150, which will be described later) is formed to penetrate the housing 100, and the core unit 200 may be coupled through the opening. In this case, the opening may be physically partitioned from the internal space of the housing 100 so that fluid communication is blocked.
The housing 100 is coupled to the first winding unit 300. Inside the housing 100, a bobbin support portion 140 surrounding the opening is formed. The first winding unit 300 is accommodated in the housing 100 and may be supported by being coupled to the bobbin support portion 140.
The housing 100 is coupled to the second winding unit 400. In the height direction of the housing 100-specifically, on the upper and lower sides in the illustrated embodiment-the second winding unit 400 is respectively positioned. In this case, the core unit 200 may penetrate the housing 100, the first winding unit 300, and the second winding unit 400, thereby coupling them together.
The housing 100 is coupled to the shield unit 500. The shield unit 500 is provided inside the housing 100 to alleviate the generated electric field and prevent electric field concentration in a specific area. In addition, the shield unit 500 may also prevent discharge phenomena of the power being conducted.
The housing 100 is coupled to the bushing 600. The bushing 600 is configured to support and fix a conductive member (not designated in the drawings) accommodated in the housing 100 and to assist in connection with an external power source (not shown) or load (not shown). In the illustrated embodiment, the bushing 600 is coupled to a front side of the housing 100. The housing 100 and the bushing 600 are in fluid communication, so that the conductive member (not designated in the drawings) may be electrically connected to other components accommodated in the housing 100.
The housing 100 is coupled to the coupling frame 700. The housing 100 may be coupled to another external component by the coupling frame 700. In the illustrated embodiment, the coupling frame 700 is respectively coupled to the upper and lower sides of the housing 100.
The housing 100 accommodates the shield member coupling portion 800. The shield unit 500, which is accommodated in the housing 100, may be stably supported by the shield member coupling portion 800.
A semiconductive layer S.C may be formed on an inner surface of the housing 100. The semiconductive layer S.C is positioned between the internal space of the housing 100 and the inner surface of the housing 100, and may alleviate the generated electric field to prevent electric field concentration and resulting dielectric breakdown.
The semiconductive layer S.C may be formed of any material capable of alleviating the electric field and uniformly forming the electric field. In an embodiment, the semiconductive layer S.C may be composed of a semiconductive material or a semiconductive thermosetting compound or the like. In an embodiment, the semiconductive layer S.C may be composed of a mixture of semiconductive polyethylene and conductive carbon black or the like.
The semiconductive layer S.C may be formed on the inner surface of the housing 100 in various forms. In an embodiment, the semiconductive layer S.C may be formed on the inner surface of the housing 100 in the form of a spray application. In the above embodiment, no separate member is required to install or fix the semiconductive layer S.C, and the semiconductive layer S.C can be formed simply by spraying, thereby improving workability.
In an embodiment, the semiconductive layer S.C may be applied to less than 90% of the area of the inner surface of the housing 100. Accordingly, the semiconductive layer S.C is not provided on approximately 10% of the area of the inner surface of the housing 100. To reliably achieve the electric field alleviation effect, the transformer 10 according to an embodiment of the present invention includes the shield unit 500. This will be described later in detail.
The housing 100 may be composed of a plurality of portions. The plurality of portions forming the housing 100 may be formed symmetrically with each other so that their structures and functions are configured identically.
In the illustrated embodiment, the housing 100 includes a first housing 101 forming an upper side and a second housing 102 forming a lower side. The first housing 101 and the second housing 102 may be formed to be planar-symmetrical with respect to a horizontal direction.
Although FIGS. 4 to 15 illustrate the second housing 102 as the main focus, it will be understood that the first housing 101 also has the same structure and function. That is, the components provided in the second housing 102, which will be described below, are also provided in the first housing 101.
In the embodiment illustrated in FIGS. 4 to 15, the housing 100 includes a housing space 110, a housing inner surface 120, a housing opening 130, a bobbin support portion 140, and a core receiving portion 150.
In addition, referring further to FIGS. 19 to 23, the housing 100 according to the illustrated embodiment further includes a housing fluid communication portion 160.
The housing space 110 is a space formed inside the housing 100. The housing space 110 is defined as a space surrounded by the housing inner surface 120 and the bobbin support portion 140. In other words, the housing space 110 is formed between the housing inner surface 120 and the bobbin support portion 140 in a radial direction. The housing space 110 is closed by the housing inner surface 120 and the bobbin support portion 140, so that fluid communication with the outside may be selectively blocked.
The housing space 110 is in fluid communication with a bushing space 620 formed inside the bushing 600. The first winding unit 300 accommodated in the housing space 110 may be electrically connected to a conductive member (not designated in the drawings) accommodated in the bushing space 620. In addition, a bushing shield member 510 accommodated in the bushing space 620 and a housing shield member 520 accommodated in the housing space 110-both components of the shield unit 500-may also be electrically connected.
The housing space 110 may be formed in a shape corresponding to the shape of the housing 100. In the illustrated embodiment, the housing space 110 is a rectangular pillar-shaped space having a rectangular cross-section and a height in the vertical direction. In this case, each corner of the housing space 110 may be rounded to bulge outward. Accordingly, electric field concentration may be alleviated.
In addition, the bobbin support portion 140 is positioned in the housing space 110. The bobbin support portion 140 extends to surround the core receiving portion 150, which is in fluid communication with the outside, and physically separates the core receiving portion 150 from the housing space 110. That is, the housing space 110 is not in fluid communication with the core receiving portion 150.
The housing space 110 may be in fluid communication with the outside through the housing fluid communication portion 160. After other components of the transformer 10 are accommodated in the housing space 110, an electrically insulating material may be injected through the housing fluid communication portion 160 and filled into the housing space 110. Accordingly, the other components accommodated in the housing space 110 may be fixed in place.
The housing space 110 formed in the first housing 101 is surrounded on all sides by the housing inner surface 120, except for one side facing the second housing 102, which is open on the lower side in the illustrated embodiment. In addition, the housing space 110 formed in the second housing 102 is surrounded on all sides by the housing inner surface 120, except for one side facing the first housing 101, which is open on the upper side in the illustrated embodiment.
The respective open sides of the first housing 101 and the second housing 102 may be closed as the first housing 101 and the second housing 102 are coupled together. That is, the first housing 101 and the second housing 102 are coupled while covering each other's open side.
The housing space 110 accommodates the first winding unit 300 coupled to the bobbin support portion 140. In addition, the housing space 110 accommodates the shield unit 500 and the shield member coupling portion 800.
After the components of the transformer 10 are arranged in the housing space 110, an electrically insulating material may be injected into the housing space 110. In an embodiment, the remaining space of the housing space 110-that is, the space excluding the area occupied by the components of the transformer 10-may be filled with the electrically insulating material.
Accordingly, each component accommodated in the housing space 110 may be stably maintained in a predetermined position. In addition, unintended electrical connections between the respective components may be prevented, thereby improving the operational reliability of the transformer 10. As described above, the electrically insulating material may be formed of a synthetic resin material such as epoxy or a silicon-based material. In another embodiment, the electrically insulating material may be provided as an insulating oil material such as mineral oil, alkylbenzene, polybutene, alkylated naphthalene, alkylated diphenyl ethane, silicone oil, a mixed oil of mineral oil and alkylbenzene, or a vegetable oil such as natural ester, or a mixture thereof.
The housing inner surface 120 is defined as a surface formed inside the housing 100. The housing inner surface 120 surrounds the housing space 110 from the outside. In this case, as described above, the housing inner surface 120 may be configured to surround the other sides of the first housing 101 and the second housing 102, excluding their respective open sides.
The housing inner surface 120 is located on the radially outer side of the housing space 110, the bobbin support portion 140, and the core receiving portion 150. When the first housing 101 and the second housing 102 are coupled together, the housing inner surface 120 is not exposed to the outside.
A plurality of housing inner surfaces 120 may be defined. The plurality of housing inner surfaces 120 may extend from one another and be configured to surround the housing space 110 at a plurality of locations. In this case, the respective portions where the housing inner surfaces 120 are continuous with each other may be rounded so that electric field concentration can be prevented.
In the illustrated embodiment, the housing inner surface 120 includes a first housing inner surface 121, a second housing inner surface 122, a third housing inner surface 123, a fourth housing inner surface 124, and a fifth housing inner surface 125.
The first housing inner surface 121 is defined as a component of the housing inner surface 120. The first housing inner surface 121 surrounds the housing space 110 from one side. In the illustrated embodiment, the first housing inner surface 121 surrounds the housing space 110 from the lower side. Accordingly, the first housing inner surface 121 provided in the first housing 101 may be defined as an upper inner surface, and the first housing inner surface 121 provided in the second housing 102 may be defined as a lower inner surface.
The bobbin support portion 140 extends from the first housing inner surface 121. In addition, the first winding unit 300 may be seated on the first housing inner surface 121.
The first housing inner surface 121 is continuous with the second housing inner surface 122, the third housing inner surface 123, the fourth housing inner surface 124, and the fifth housing inner surface 125.
The second housing inner surface 122 is defined as another component of the housing inner surface 120. The second housing inner surface 122 surrounds the housing space 110 from another side. In the illustrated embodiment, the second housing inner surface 122 surrounds the housing space 110 from the front side. Accordingly, the second housing inner surface 122 may be defined as a front inner surface. The second housing inner surface 122 is disposed to face the third housing inner surface 123 with the housing space 110 interposed therebetween.
A housing opening 130 is formed to penetrate the second housing inner surface 122. The housing opening 130 provides fluid communication between the housing space 110 and the bushing space 620. The first winding unit 300 may be electrically connected to a conductive member (not designated in the drawings) accommodated in the bushing space 620 through the housing opening 130.
A housing shield member 520 is positioned on the second housing inner surface 122. The housing shield member 520 is electrically connectable to the bushing shield member 510 accommodated in the bushing space 620. In the illustrated embodiment, the housing shield member 520 extends along the width direction, that is, the left-right direction of the second housing inner surface 122, and is electrically connectable to the bushing shield member 510.
The third housing inner surface 123 is defined as yet another component of the housing inner surface 120. The third housing inner surface 123 surrounds the housing space 110 from yet another side. In the illustrated embodiment, the third housing inner surface 123 surrounds the housing space 110 from the rear side. Accordingly, the third housing inner surface 123 may be defined as a rear inner surface. The third housing inner surface 123 is disposed to face the second housing inner surface 122 with the housing space 110 interposed therebetween.
A housing fluid communication portion 160 may be positioned on the third housing inner surface 123 (see FIGS. 19 to 23). In the above embodiment, a through-hole is formed in the third housing inner surface 123 and may be in fluid communication with a hollow portion formed inside the housing fluid communication portion 160. The electrically insulating material may be filled into the housing space 110 through the through-hole.
A housing shield member 520 is positioned on the third housing inner surface 123. The housing shield member 520 is electrically connectable to the housing shield members 520 positioned on the fourth housing inner surface 124 and the fifth housing inner surface 125, respectively. In the illustrated embodiment, the housing shield member 520 extends along the width direction, that is, the left-right direction of the third housing inner surface 123, and each end in the extending direction is electrically connectable to the housing shield members 520 positioned on the fourth and fifth housing inner surfaces 124 and 125, respectively.
The fourth housing inner surface 124 is defined as still another component of the housing inner surface 120. The fourth housing inner surface 124 surrounds the housing space 110 from still another side. In the illustrated embodiment, the fourth housing inner surface 124 surrounds the housing space 110 from the left side. Accordingly, the fourth housing inner surface 124 may be defined as a left inner surface. The fourth housing inner surface 124 is disposed to face the fifth housing inner surface 125 with the housing space 110 interposed therebetween.
A housing shield member 520 is positioned on the fourth housing inner surface 124. The housing shield member 520 is electrically connectable to the housing shield members 520 positioned on the second housing inner surface 122 and the third housing inner surface 123, respectively. In the illustrated embodiment, the housing shield member 520 extends along the width direction, that is, the front-rear direction of the fourth housing inner surface 124, and each end in the extending direction is electrically connectable to the housing shield members 520 positioned on the second and third housing inner surfaces 122 and 123, respectively.
The fifth housing inner surface 125 is defined as an additional component of the housing inner surface 120. The fifth housing inner surface 125 surrounds the housing space 110 from an additional side. In the illustrated embodiment, the fifth housing inner surface 125 surrounds the housing space 110 from the right side. Accordingly, the fifth housing inner surface 125 may be defined as a right inner surface. The fifth housing inner surface 125 is disposed to face the fourth housing inner surface 124 with the housing space 110 interposed therebetween.
A housing shield member 520 is positioned on the fifth housing inner surface 125. The housing shield member 520 is electrically connectable to the housing shield members 520 positioned on the second housing inner surface 122 and the third housing inner surface 123, respectively. In the illustrated embodiment, the housing shield member 520 extends along the width direction, that is, the front-rear direction of the fifth housing inner surface 125, and each end in the extending direction is electrically connectable to the housing shield members 520 positioned on the second and third housing inner surfaces 122 and 123, respectively.
In an embodiment, semiconductive layers S.C may be formed on the first to fifth housing inner surfaces 121, 122, 123, 124, and 125. As described above, the total area of the semiconductive layers S.C formed on the housing inner surface 120 may be less than 90% of the total area of the housing inner surface 120.
The housing opening 130 provides fluid communication between the housing space 110 and the bushing space 620. The housing opening 130 is formed to penetrate one of the plurality of housing inner surfaces 120, specifically the surface facing the bushing 600. In the illustrated embodiment, the housing opening 130 is formed to penetrate the second housing inner surface 122, which is positioned on the front side.
The housing opening 130 functions as a passage through which the bushing shield member 510 of the shield unit 500 is exposed to the housing space 110. The bushing shield member 510 is accommodated in the bushing space 620 and may be positioned to be partially exposed to the housing space 110. The housing opening 130 is in fluid communication with the housing space 110 and the bushing space 620, respectively.
The housing opening 130 provides fluid communication between the housing space 110 and the bushing space 620, and may have any shape that allows the bushing shield member 510 to pass through. In the illustrated embodiment, the housing opening 130 has a cylindrical shape having a circular cross-section, and a length in the front-rear direction.
A through-hole (not designated in the drawings), through which a grounding member passes, may be formed to penetrate an inner circumferential surface of the housing 100 (or the bushing 600) that surrounds the housing opening 130 or the bushing space 620. The shield unit 500 may be electrically connected to an external ground through the through-hole.
In the embodiment illustrated in FIGS. 7 to 9, a semiconductive layer S.C may be partially formed on an inner circumferential surface of the housing 100 or the bushing body 610 that surrounds the housing opening 130. Specifically, the semiconductive layer S.C and the bushing shield member 510 may be partially overlapped with each other in the radial direction. In other words, one end of the semiconductive layer S.C-specifically, the front end directed toward the bushing cover 630-may be positioned on the bushing shield member 510.
The bobbin support portion 140 is coupled to the first winding unit 300 accommodated in the housing space 110. The bobbin support portion 140 supports the coupled first winding unit 300. The bobbin support portion 140 is formed in the housing space 110.
The bobbin support portion 140 extends from the first housing inner surface 121 toward one open side of the housing space 110, which is the upper side in the illustrated embodiment. The bobbin support portion 140 is disposed inside the housing inner surface 120, spaced apart from the housing inner surface 120. In other words, the bobbin support portion 140 is disposed to face the housing inner surface 120 with the housing space 110 interposed therebetween.
In an embodiment, the bobbin support portion 140 may be inserted into and coupled with a first bobbin space 321 provided in the first winding unit 300. In the above embodiment, the bobbin support portion 140 may be formed in a shape corresponding to the first bobbin space 321.
In the illustrated embodiment, the bobbin support portion 140 includes a pair of surfaces extending in the longitudinal direction of the housing 100 and another pair of surfaces extending in the width direction. Specifically, the bobbin support portion 140 includes a pair of surfaces extending in the front-rear direction, and another pair of surfaces extending in the left-right direction, the latter being continuous with the former. The pair of surfaces are disposed to face each other with the core receiving portion 150 interposed therebetween. The other pair of surfaces are also disposed to face each other with the core receiving portion 150 interposed therebetween.
That is, the bobbin support portion 140 is in the shape of a rectangular pillar having a rectangular cross-section and a height in the vertical direction, with the core receiving portion 150 formed to penetrate therethrough. Inside the bobbin support portion 140, the core receiving portion 150, which is open in the height direction-specifically, the vertical direction in the illustrated embodiment-is located. In other words, the bobbin support portion 140 is formed to surround the core receiving portion 150 from the outside.
A plurality of bobbin support portions 140 may be provided. The plurality of bobbin support portions 140 may be spaced apart from each other and respectively coupled to a plurality of first winding units 300. In the illustrated embodiment, the bobbin support portions 140 include a first bobbin support portion 141 positioned closer to the fourth housing inner surface 124 and a second bobbin support portion 142 positioned closer to the fifth housing inner surface 125.
In the embodiment illustrated in FIGS. 8 and 9, a semiconductive layer S.C may be formed on an outer surface of the bobbin support portion 140, specifically, the surface that surrounds the housing space 110. In this case, the semiconductive layer S.C may be formed to cover an area equal to or smaller than the surface area of the outer surface of the bobbin support portion 140. In the illustrated embodiment, the semiconductive layer S.C is formed such that its upper end is positioned lower than the upper end of the bobbin support portion 140.
In addition, in the embodiment illustrated in FIG. 9, a housing shield member 520 may further be provided on the outer surface of the bobbin support portion 140. The housing shield member 520 may be positioned to be in contact with the semiconductive layer S.C formed on the outer surface of the bobbin support portion 140, and may be configured to alleviate the electric field.
The core receiving portion 150 is a space in which the core unit 200 is coupled. The core receiving portion 150 extends in the height direction of the housing 100, specifically in the vertical direction in the illustrated embodiment. Each end of the core receiving portion 150 in the extending direction-namely, the upper and lower sides in the illustrated embodiment-is open so that the core unit 200 can pass therethrough.
The core receiving portion 150 is partially surrounded by the bobbin support portion 140. In the illustrated embodiment, the core receiving portion 150 is surrounded in its radial direction-namely, the front, rear, left, and right sides-by the bobbin support portion 140.
The core receiving portion 150 may have any shape capable of accommodating the core unit 200. In the illustrated embodiment, the core receiving portion 150 has a rectangular pillar shape, with an extension length in the front-rear direction longer than that in the left-right direction, and a height in the vertical direction.
A plurality of core receiving portions 150 may be formed. The plurality of core receiving portions 150 may be respectively formed inside the plurality of bobbin support portions 140. In the illustrated embodiment, the core receiving portions 150 include a first core receiving portion 151 formed inside the first bobbin support portion 141 and a second core receiving portion 152 formed inside the second bobbin support portion 142.
As described above, the bobbin support portion 140 and the core receiving portion 150 are respectively formed in the first housing 101 and the second housing 102. When the first housing 101 and the second housing 102 are coupled, the bobbin support portions 140 and the core receiving portions 150 formed in the respective housings 101 and 102 are aligned in the coupling direction, which is the vertical direction in the illustrated embodiment.
Referring further to FIGS. 19 to 23, the housing 100 according to the illustrated embodiment further includes a housing fluid communication portion 160.
The housing fluid communication portion 160 provides fluid communication between the housing space 110 and the outside. The housing fluid communication portion 160 functions as a passage through which the electrically insulating material to be filled into the housing space 110 flows in.
The housing fluid communication portion 160 is coupled to one side of the housing 100. A hollow is formed to penetrate the inside of the housing fluid communication portion 160, providing fluid communication with both the housing space 110 and the outside.
In the illustrated embodiment, the housing fluid communication portion 160 is located at the rear side of the housing 100 and is in fluid communication with a through-hole formed in the third housing inner surface 123. The housing fluid communication portion 160 may be formed at any position capable of providing fluid communication between the housing space 110 and the outside.
After the components of the transformer 10 are accommodated in the housing space 110 and the electrically insulating material is filled, the housing fluid communication portion 160 may be closed. For example, the housing fluid communication portion 160 may be separated from the housing 100, and the through-hole formed in the housing inner surface 120 may be closed so that fluid communication between the housing space 110 and the outside is blocked.
The housing fluid communication portion 160 may have any shape that can provide fluid communication between the housing space 110 and the outside. In the illustrated embodiment, the housing fluid communication portion 160 has a cylindrical shape with a hollow formed therein.
The core unit 200 is magnetized by a current applied to any one of the plurality of first winding units 300 or any one of the plurality of second winding units 400, thereby generating magnetic flux. The generated magnetic flux may induce a current in another one of the plurality of first winding units 300 or another one of the plurality of second winding units 400.
The core unit 200 is coupled to the housing 100. In the illustrated embodiment, the core unit 200 includes a first core unit 201 positioned on the upper side and a second core unit 202 positioned on the lower side. The first core unit 201 is coupled to the core receiving portion 150 provided in the first housing 101. The second core unit 202 is coupled to the core receiving portion 150 provided in the second housing 102.
When the first housing 101 and the second housing 102 are coupled, the first core unit 201 and the second core unit 202 may also come into contact with each other. The first core unit 201 and the second core unit 202 accommodated in the core receiving portion 150 are not exposed to the housing space 110.
The core unit 200 is coupled to the first winding unit 300. Specifically, the core unit 200 may be disposed to face the first winding unit 300 with the bobbin support portion 140 interposed therebetween. In other words, the first winding unit 300, the bobbin support portion 140, and the core unit 200 are arranged side by side in the radial direction.
The core unit 200 is coupled to the second winding unit 400. Specifically, the core unit 200 may be inserted through and coupled to the second winding unit 400, which is supported on an outer surface of the housing 100. In other words, the core unit 200 and the second winding unit 400 are arranged side by side in the radial direction.
Since the process in which the core unit 200 is magnetized by a current and induces a current is well known in the art, a detailed description thereof will be omitted.
The first winding unit 300 is coupled to the core unit 200. The first winding unit 300 is electrically connectable to one of an external power source and a load. The first winding unit 300 may receive a current to magnetize the core unit 200, or may deliver a current induced by the core unit 200 to the outside.
The first winding unit 300 is accommodated in the housing space 110. The first winding unit 300 may be supported by being coupled to the bobbin support portion 140 positioned in the housing space 110. In an embodiment, the bobbin support portion 140 may be inserted into and coupled to the first winding unit 300.
The first winding unit 300 is positioned adjacent to the core unit 200. The first winding unit 300 is disposed to face the core unit 200 with the bobbin support portion 140 interposed therebetween.
A plurality of first winding units 300 may be provided. One of the plurality of first winding units 300 may be coupled to one side of the core unit 200, and another one of the plurality of first winding units 300 may be coupled to the other side of the core unit 200. In the illustrated embodiment, two first winding units 300 are provided and are coupled to the left and right sides of the core unit 200, respectively.
The first winding unit 300 is electrically connected to an external power source or load. The first winding unit 300 may be electrically connectable to the external power source or load through the bushing 600 by means of a conductive member (not designated in the drawings). In an embodiment, high-voltage power may be conducted through the first winding unit 300.
In the illustrated embodiment, the first winding unit 300 includes a first coil 310 and a first bobbin 320.
The first coil 310 is electrically connectable to an external power source or load. The first coil 310 is wound around the first bobbin 320. In other words, the first coil 310 is coupled to the bobbin support portion 140 or the core unit 200 via the first bobbin 320.
The first bobbin 320 holds the first coil 310 wound therearound. As the name suggests, the first bobbin 320 may function as a bobbin.
A first bobbin space 321 is formed inside the first bobbin 320. The first bobbin space 321 extends in the height direction of the first bobbin 320, specifically in the vertical direction in the illustrated embodiment, with both ends in the height direction-namely, the upper and lower ends-being open. The bobbin support portion 140 may be inserted into and coupled with the first bobbin space 321.
The first bobbin 320 and the first bobbin space 321 may have shapes corresponding to those of the bobbin support portion 140 and the core unit 200. In the illustrated embodiment, the first bobbin 320 and the first bobbin space 321 formed therein have a polygonal pillar shape, with an extension length in the front-rear direction longer than that in the left-right direction, and a height in the vertical direction.
Although not illustrated, semiconductive layers S.C may be formed on each surface of the first bobbin 320 in the height direction-specifically, on the lower surface and the upper surface in the illustrated embodiment. In addition, semiconductive layers S.C may also be formed on the surfaces of the first bobbin 320 in the radial direction, which are in contact with the first coil 310-specifically, on the side surfaces in the illustrated embodiment.
Since the process in which a current is induced and conducted between the plurality of first winding units 300 coupled to the core unit 200 is well known in the art, a detailed description thereof will be omitted.
The second winding unit 400 is coupled to the core unit 200. The second winding unit 400 is electrically connectable to the other one of an external power source and a load. The second winding unit 400 may receive a current to magnetize the core unit 200, or may deliver a current induced by the core unit 200 to the outside.
The second winding unit 400 is located outside the housing 100. In the illustrated embodiment, the second winding unit 400 is positioned adjacent to the upper outer surface and the lower outer surface of the housing 100, respectively.
The second winding unit 400 is positioned adjacent to the core unit 200. The core unit 200 may be inserted through and coupled to the second winding unit 400.
A plurality of second winding units 400 may be provided. One of the plurality of second winding units 400 may be coupled to one side of the core unit 200, and another one of the plurality of second winding units 400 may be coupled to the other side of the core unit 200. In the illustrated embodiment, two second winding units 400 are provided and are coupled to the left and right sides of the core unit 200, respectively.
The second winding unit 400 may be configured in a plurality of pairs. One pair of the plurality of pairs of second winding units 400 may be located on one side of the housing 100, and another pair may be located on the other side of the housing 100. In the illustrated embodiment, two pairs of second winding units 400 are provided and are respectively located on the upper and lower sides of the housing 100.
The second winding unit 400 is electrically connected to an external power source or load. The second winding unit 400 may be electrically connectable to the external power source or load via a wire member (not shown) or the like. In an embodiment, low-voltage power may be conducted through the second winding unit 400.
In the illustrated embodiment, the second winding unit 400 includes a second coil 410 and a second bobbin 420.
The second coil 410 is electrically connectable to an external power source or load. The second coil 410 is wound around the second bobbin 420. In other words, the second coil 410 is coupled to the housing 100 and the core unit 200 via the second bobbin 420.
The second bobbin 420 holds the second coil 410 wound therearound. As the name suggests, the second bobbin 420 may function as a bobbin.
A second bobbin space 421 is formed inside the second bobbin 420. The second bobbin space 421 extends in the height direction of the second bobbin 420, specifically in the vertical direction in the illustrated embodiment, with both ends in the height direction-namely, the upper and lower ends-being open.
The core unit 200 may be inserted through and coupled to the second bobbin space 421.
The second bobbin 420 and the second bobbin space 421 may have shapes corresponding to that of the core unit 200. In the illustrated embodiment, the second bobbin 420 and the second bobbin space 421 formed therein have a polygonal pillar shape, with an extension length in the front-rear direction longer than that in the left-right direction, and a height in the vertical direction.
Although not illustrated, semiconductive layers S.C may be formed on each surface of the second bobbin 420 in the height direction-specifically, on the lower surface and the upper surface in the illustrated embodiment. In addition, semiconductive layers S.C may also be formed on the surfaces of the second bobbin 420 in the radial direction, which are in contact with the second coil 410-specifically, on the side surfaces in the illustrated embodiment.
Since the process in which a current is induced and conducted between the plurality of second winding units 400 coupled to the core unit 200 is well known in the art, a detailed description thereof will be omitted.
Although not illustrated, a semiconductive layer S.C may be formed on a surface of the second bobbin 420 facing the housing 100-specifically, on the lower surface of the second bobbin 420 positioned above the housing 100 and on the upper surface of the second bobbin 420 positioned below the housing 100.
The shield unit 500 substantially serves to alleviate the generated electric field and prevent dielectric breakdown. The shield unit 500 is accommodated in the housing space 110 and is configured to be spaced apart from components through which current is directly conducted, such as the core unit 200, the first winding unit 300, and the conductive member (not designated in the drawings).
The shield unit 500 is coupled to the housing 100. The shield unit 500 is fixedly coupled to the housing 100 so as not to move arbitrarily. As will be described later, a shield member coupling portion 800 may further be provided to secure the shield unit 500.
The shield unit 500 may be disposed in contact with the semiconductive layer S.C formed inside the housing 100. The shield unit 500 may be electrically connected to the semiconductive layer S.C and configured to prevent electric field concentration and partial discharge in cooperation with the semiconductive layer S.C.
The shield unit 500 may be formed of an electrically conductive material. In an embodiment, the shield unit 500 may be formed of an aluminum (Al) material. The shield unit 500 may guide a portion of the electric field generated by the first winding unit 300 or the second winding unit 400 back to the first winding unit 300 or the second winding unit 400.
A plurality of shield units 500 may be provided. The plurality of shield units 500 may be coupled to the housing 100 at different positions. In this case, the plurality of shield units 500 may be electrically connected to each other and configured to collectively perform insulation and alleviation of the generated electric field.
In the illustrated embodiment, the shield unit 500 includes a bushing shield member 510 and a housing shield member 520.
The bushing shield member 510 is positioned at a point where the housing 100 and the bushing 600 are joined, and is configured to alleviate an electric field generated from the first winding unit 300 and a conductive member (not designated in the drawings) electrically connected thereto.
The bushing shield member 510 is accommodated in the bushing space 620. Specifically, a portion of the bushing shield member 510 may be accommodated in the bushing space 620. The remaining portion of the bushing shield member 510 may be exposed to the housing space 110 through the housing opening 130. In the illustrated embodiment, the bushing shield member 510 is positioned adjacent to one end of the bushing space 620 in the extending direction-namely, the rear end facing the housing 100.
The bushing shield member 510 may be electrically connectable to an external ground. Accordingly, the housing shield member 520, which is electrically connectable to the bushing shield member 510, may also be electrically connectable to the external ground.
The bushing shield member 510 may be disposed to be partially overlapped with the semiconductive layer S.C. In the illustrated embodiment, the bushing shield member 510 is formed to extend in the front-rear direction. In this case, the semiconductive layer S.C may also be partially applied to the inner circumferential surface of the bushing body 610, which surrounds the bushing space 620 accommodating the bushing shield member 510. Accordingly, the front end of the semiconductive layer S.C may be positioned between the front end and the rear end of the bushing shield member 510.
In this case, the semiconductive layer S.C may extend such that it does not contact the portion of the bushing shield member 510 that is electrically connectable to the external ground. In other words, in the illustrated embodiment, the front end of the semiconductive layer S.C is positioned between the above-described portion of the bushing shield member 510 and the rear end of the bushing shield member 510.
This is because, if the semiconductive layer S.C is formed up to the above-described portion of the bushing shield member 510, there is a risk of electric field breakdown occurring between the ground and the first winding unit 300. In addition, if the semiconductive layer S.C extends to the rear end of the bushing shield member 510, there is a risk that the electric field may become concentrated at the front end of the semiconductive layer S.C.
Therefore, it is preferable that the semiconductive layer S.C is formed such that its boundary is located between the end of the bushing shield member 510 in the extending direction facing the housing space 110 and the portion connected to the external ground.
The bushing shield member 510 may have any shape capable of alleviating the generated electric field by being electrically connectable to the housing shield member 520 and the external ground. In the illustrated embodiment, the bushing shield member 510 has a cylindrical shape having an annular cross-section and extending in the front-rear direction, with a hollow portion formed therein. It will be understood that the shape of the bushing shield member 510 corresponds to the shape of the one end-namely, the rear end-of the bushing space 620.
A conductive member (not designated in the drawings) passes through the hollow formed inside the bushing shield member 510, electrically connecting the first winding unit 300 to an external power source or load.
Although not illustrated, the outer circumferential surface of the bushing shield member 510 may be formed in a mesh shape including a plurality of through-holes. In the above embodiment, the hollow formed inside the bushing shield member 510 may be in fluid communication with the housing space 110 or the bushing space 620 in the radial direction through the through-holes.
Accordingly, when the electrically insulating material is filled through the housing fluid communication portion 160, the electrically insulating material introduced into the hollow may flow radially outward through the through-holes, thereby preventing the bushing shield member 510 from moving arbitrarily.
To fix the bushing shield member 510 to the bushing 600, a fastening member (not designated in the drawings) may be provided, which is coupled to a through-hole formed in the inner circumferential surface of the bushing body 610 that surrounds the bushing space 620. The fastening member (not designated in the drawings) may be respectively coupled to the through-hole and the bushing shield member 510 to couple the bushing shield member 510 to the housing 100.
The housing shield member 520 is coupled to the housing inner surface 120 or the bobbin support portion 140 and is configured to alleviate the electric field generated from the first winding unit 300.
The housing shield member 520 is positioned in the housing space 110. The housing shield member 520 may be positioned on the housing inner surface 120 that surrounds the housing space 110 from the radially outer side, or on the bobbin support portion 140 that surrounds the housing space 110 from the radially inner side.
The housing shield member 520 may be disposed in contact with the semiconductive layer S.C. As described above, in an embodiment in which the semiconductive layer S.C is formed to cover less than 90% of the area of the housing inner surface 120, the housing shield member 520 may be disposed to overlap with or contact an end of the semiconductive layer S.C. Accordingly, the housing shield member 520 may be electrically connectable to the semiconductive layer S.C.
The housing shield member 520 is electrically connectable to the bushing shield member 510. As illustrated in FIG. 6, among the housing shield members 520, the housing shield member 520 positioned on the second housing inner surface 122 is electrically connectable to the left and right sides of the bushing shield member 510, respectively.
The housing shield member 520 is electrically connectable to an external ground. This is achieved by the electrical connection between the housing shield member 520 and the bushing shield member 510, as described above.
The housing shield member 520 may extend across each side surface among the plurality of housing inner surfaces 120, namely, the second to fifth housing inner surfaces 122, 123, 124, and 125. In other words, the housing shield member 520 may extend while surrounding the housing space 110 from the radially outer side.
Referring to FIG. 8, the housing shield member 520 may extend along the outer surface of the bobbin support portion 140, that is, along each surface of the bobbin support portion 140 that surrounds the housing space 110 from the radially inner side. In the above embodiment, the housing shield member 520 disposed on the housing inner surface 120 and the housing shield member 520 disposed on the surface of the bobbin support portion 140 may be electrically connectable to each other.
In addition, as described above, the housing shield member 520 disposed on the bobbin support portion 140 may be positioned to be spaced apart from the end in the extending direction of the bobbin support portion 140-specifically, the upper end in the illustrated embodiment.
The above-described semiconductive layer S.C and the housing shield member 520 may be modified and applied in various forms.
Referring to FIG. 7, the semiconductive layer S.C may be formed on the first to fifth housing inner surfaces 121, 122, 123, 124, and 125 so that the generated electric field can be alleviated.
In the above embodiment, the semiconductive layer S.C may be formed over the entire surface of the first housing inner surface 121. In other words, the area of the semiconductive layer S.C formed on the first housing inner surface 121 may be equal to the area of the first housing inner surface 121.
In addition, in the above embodiment, the semiconductive layer S.C may be formed to partially cover the second to fifth housing inner surfaces 122, 123, 124, and 125. In other words, the combined area of the second to fifth housing inner surfaces 122, 123, 124, and 125 may be greater than the combined area of the semiconductive layers S.C formed on those surfaces.
In an embodiment, the semiconductive layer S.C may be formed on the surface of the first housing inner surface 121, in a region between the housing shield members 520 positioned on the second to fifth housing inner surfaces 122, 123, 124, and 125. In this case, the semiconductive layer S.C may be positioned in contact with the housing shield members 520 and may be electrically connectable to the housing shield members 520. Accordingly, the semiconductive layer S.C may be configured to prevent electric field concentration and dielectric breakdown in cooperation with the housing shield members 520.
Referring to FIG. 8, the semiconductive layer S.C may be additionally formed on the outer surface of the bobbin support portion 140, thereby alleviating the generated electric field. In this case, the area of the semiconductive layer S.C formed on the outer surface of the bobbin support portion 140 may be equal to or less than the area of the outer surface of the bobbin support portion 140. In the illustrated embodiment, the semiconductive layer S.C formed on the outer surface of the bobbin support portion 140 is positioned such that its upper end is spaced apart from the upper end of the bobbin support portion 140.
Referring to FIG. 9, the housing shield member 520 may also be provided on the bobbin support portion 140. In this case, the housing shield member 520 provided on the bobbin support portion 140 may be electrically connected by being in contact with the semiconductive layer S.C formed on the bobbin support portion 140. Such a connection may be established by the semiconductive layer S.C in contact with each housing shield member 520, or by a separate wire member (not shown) or the like.
Accordingly, the semiconductive layer S.C may be configured to prevent electric field concentration and dielectric breakdown in cooperation with the housing shield members 520 coupled to the bobbin support portion 140.
The bushing 600 accommodates a conductive member (not shown) that electrically connects the first winding unit 300, which is accommodated in the housing space 110, to the outside. The bushing 600 is coupled to and in fluid communication with the housing 100. The bushing 600 extends in a direction opposite to the housing 100, namely, toward the front side in the illustrated embodiment.
The bushing 600 may be formed of an electrically insulating material. In an embodiment, the bushing 600 may be provided as a synthetic resin material such as epoxy or a silicone based material. In another embodiment, the electrically insulating material may be provided as an insulating oil material such as mineral oil, alkylbenzene, polybutene, alkylated naphthalene, alkylated diphenyl ethane, silicone oil, a mixed oil of mineral oil and alkylbenzene, or a vegetable oil such as natural ester, or a mixture thereof.
The bushing 600 may be integrally formed with the housing 100 or may be formed separately from the housing 100 and then coupled to the housing 100. In the illustrated embodiment, it is assumed that the bushing 600 is integrally formed with the housing 100. In the above embodiment, the bushing 600 may also be understood as one component of the housing 100.
In the illustrated embodiment, the bushing 600 includes a bushing body 610, a bushing space 620, and a bushing cover 630.
The bushing body 610 forms a portion of the bushing 600 that is exposed to the outside. The bushing body 610 is coupled to the housing 100. The bushing space 620 is formed inside the bushing body 610.
The bushing body 610 may have any shape that can increase the creepage distance. In the illustrated embodiment, the bushing body 610 has a cylindrical shape extending in the front-rear direction with a circular cross-section, and a plurality of disc-shaped structures protruding in the radial direction are formed on its outer circumference.
One end of the bushing body 610 in the extending direction-specifically, the rear end in the illustrated embodiment-facing the housing 100 is continuous with the housing 100. The other end of the bushing body 610 in the extending direction-specifically, the front end in the illustrated embodiment-opposite to the housing 100 is coupled to the bushing cover 630.
The bushing body 610 may be divided into a plurality of parts. Each of the plurality of parts into which the bushing body 610 is divided may be coupled to the first housing 101 and the second housing 102, respectively. In the illustrated embodiment, the bushing body 610 includes a first bushing body 611, which is positioned at an upper side and coupled to the first housing 101, and a second bushing body 612, which is coupled to the second housing 102.
An inner circumferential surface at one end in the extending direction of the first bushing body 611 and the second bushing body 612--namely, the rear end in the illustrated embodiment-may surround the housing opening 130 in a radial direction. In addition, through holes may be formed in the inner circumferential surface at the above-described end in the extending direction of the first bushing body 611 and the second bushing body 612, to fix the shield unit 500 to the housing 100 and electrically connect it to an external ground.
The bushing space 620 is a space formed inside the bushing body 610. The bushing space 620 is in fluid communication with the housing space 110 through the housing opening 130. A conductive member (not designated in the drawings), which is electrically connectable to the first winding unit 300, may extend across the bushing space 620 to be electrically connectable to an external power source or load.
In addition, the electrically insulating material filled into the housing space 110 through the housing fluid communication portion 160 may flow into the bushing space 620 through the housing opening 130.
The bushing cover 630 is coupled to the bushing body 610 and maintains the coupled state of the first bushing body 611 and the second bushing body 612. In addition, the bushing cover 630 is coupled to and supports the conductive member (not designated in the drawings). The bushing cover 630 is located at the other end of the bushing body 610 in the extending direction-specifically, the front side in the illustrated embodiment-opposite to the housing 100.
When the bushing cover 630 is coupled to the bushing body 610, fluid communication between the bushing space 620 and the outside is blocked. Accordingly, the electrically insulating material filled into the housing space 110 also fills the bushing space 620, but is prevented from leaking to the outside.
The coupling frame 700 is coupled to the housing 100 and the second winding unit 400 to maintain their engagement. In addition, the coupling frame 700 serves as a portion through which the transformer 10 is coupled to another external component.
The coupling frame 700 is coupled to the housing 100 and the second winding unit 400. Specifically, the coupling frame 700 covers the second winding unit 400 positioned outside the housing 100 and is coupled to both the housing 100 and the second winding unit 400.
A plurality of coupling frames 700 may be provided. The plurality of coupling frames 700 may be coupled to the housing 100 and the second winding unit 400 at different positions, respectively, to support them. In the illustrated embodiment, the coupling frame 700 includes a first coupling frame 710 positioned on the upper side and a second coupling frame 720 positioned on the lower side.
The first coupling frame 710 is coupled to the first housing 101 and the second winding unit 400 positioned on the upper side. The second coupling frame 720 is coupled to the second housing 102 and the second winding unit 400 positioned on the lower side.
Referring to FIGS. 10 to 15, the transformer 10 according to an embodiment of the present invention further includes a shield member coupling portion 800.
The shield member coupling portion 800 supports the shield unit 500 coupled to the housing 100-specifically, the housing shield member 520. By means of the shield member coupling portion 800, the coupling state between the housing 100 and the housing shield member 520 can be stably maintained.
As described above, an electrically insulating material may be filled inside the housing 100. At this time, as the shield member coupling portion 800 supports the housing shield member 520, the housing shield member 520 is prevented from being unintentionally dislodged or separated from the housing 100 by the filled electrically insulating material.
In the illustrated embodiment, the shield member coupling portion 800 includes an accommodating groove 810, a support member 820, and a support layer 830.
Referring to FIG. 10, an embodiment in which the housing shield member 520 is supported by the accommodating groove 810 is shown.
The accommodating groove 810 is formed in the inner surface of the housing 120 to which the housing shield member 520 is coupled, namely, in the second to fifth housing inner surfaces 122, 123, 124, and 125. The accommodating groove 810 is recessed in a direction opposite to the housing space 110, namely, toward the outside in the illustrated embodiment.
The accommodating groove 810 may have a shape corresponding to the shape of the housing shield member 520. In the illustrated embodiment, the housing shield member 520 has a band shape with a circular cross-section, and accordingly, the accommodating groove 810 may also be formed to have a cross-section in the shape of a portion of a circle.
In the illustrated embodiment, the diameter of the cross-section of the accommodating groove 810 may be equal to or smaller than that of the housing shield member 520. Accordingly, the housing shield member 520 may be fitted into the accommodating groove 810, thereby preventing unintentional disengagement of the housing shield member 520.
The accommodating groove 810 may extend corresponding to the housing shield member 520. In the illustrated embodiment, the housing shield member 520 extends across the second to fifth housing inner surfaces 122, 123, 124, and 125. Accordingly, the accommodating groove 810 may also extend across the second to fifth housing inner surfaces 122, 123, 124, and 125.
The accommodating groove 810 may be spaced apart from the first housing inner surface 121 by a predetermined distance. In other words, the accommodating groove 810 may be positioned at a predetermined height. In this case, the accommodating groove 810 may be disposed so as to at least partially overlap with the semiconductive layer S.C in the radial direction. In other words, the housing shield member 520 accommodated in the accommodating groove 810 may be in contact with the semiconductive layer S.C at least partially.
In addition, the area of the portion of the second to fifth housing inner surfaces 122, 123, 124, and 125 that is located above the accommodating groove 810-that is, the portion where the semiconductive layer S.C is not formed-may be 10% or more of the total area of the housing inner surface 120.
Referring to FIGS. 11 and 12, an embodiment in which the housing shield member 520 is supported by the support member 820 is illustrated.
The support member 820 is formed on the housing inner surfaces 520 to which the housing shield member 520 is coupled-namely, the second to fifth housing inner surfaces 122, 123, 124, and 125. The support member 820 protrudes toward the housing space 110-specifically, toward the inner side in the illustrated embodiment.
The support member 820 may include a plurality of pairs that support the housing shield member 520 at different positions. In this case, each pair of support members 820 may also be spaced apart from each other and disposed to face each other with the housing shield member 520 interposed therebetween.
In the illustrated embodiment, a pair of support members 820 are respectively positioned above and below the housing shield member 520, and are configured to support the upper and lower sides of the housing shield member 520.
In addition, the plurality of pairs of support members 820 are spaced apart from each other along the extending direction of the housing shield member 520, thereby supporting the housing shield member 520 at multiple positions. In the illustrated embodiment, each pair of support members 820 are spaced apart by a predetermined distance and are arranged along the housing shield member 520 on the second to fifth housing inner surfaces 122, 123, 124, and 125.
The support member 820 may have any shape capable of supporting the housing shield member 520. In the illustrated embodiment, the support member 820 has the shape of a truncated cone, with its cross-sectional diameter decreasing in a radially inward direction. In this case, a protrusion is formed at an end of the support member 820 in the extending direction, so that disengagement of the housing shield member 520 can be prevented.
The support member 820 may be disposed to be spaced apart from the first housing inner surface 121 by a predetermined distance. In other words, the support member 820 may be positioned at a predetermined height. In this case, the support member 820 located on the lower side of the pair of support members 820 may be disposed to overlap the semiconductive layer S.C in a radial direction. In other words, the housing shield member 520 positioned between the pair of support members 820 may be in partial contact with the semiconductive layer S.C.
In addition, the area of the portion of the second to fifth housing inner surfaces 122, 123, 124, and 125 that is located above the upper one of the pair of support members 820-i.e., the portion where the semiconductive layer S.C is not formed-may be equal to or greater than 10% of the total area of the housing inner surface 120.
Referring to FIGS. 13 to 15, an embodiment in which the housing shield member 520 is supported by the accommodating groove 810 and the support layer 830 is illustrated.
In the present embodiment, the radially outer portion of the housing shield member 520 (i.e., the portion opposite to the housing space 110) is inserted into the accommodating groove 810, which is recessed into the second to fifth housing inner surfaces 122, 123, 124, and 125. In addition, the radially inner portion of the housing shield member 520 (i.e., the portion facing the housing space 110) is supported by the support layer 830.
The accommodating groove 810 according to the present embodiment has the same structure and function as the accommodating groove 810 of the above-described embodiment. Accordingly, the support structure of the housing shield member 520 according to the present embodiment will be described below with a focus on the support layer 830.
The support layer 830 is coupled to the housing 100 and accommodated in the housing space 110. The support layer 830 is configured to support the housing shield member 520, which is coupled to the second to fifth housing inner surfaces 122, 123, 124, and 125, from the inner side.
In an embodiment in which the housing shield member 520 is also coupled to the bobbin support portion 140, the support layer 830 may be configured to support the housing shield member 520 coupled to the bobbin support portion 140 from the outer side.
The support layer 830 may be formed of an electrically insulating material. In an embodiment, the support layer 830 may be made of a synthetic resin material such as epoxy or a silicone based material. In another embodiment, the electrically insulating material may be provided as an insulating oil material such as mineral oil, alkylbenzene, polybutene, alkylated naphthalene, alkylated diphenyl ethane, silicone oil, a mixed oil of mineral oil and alkylbenzene, or a vegetable oil such as natural ester, or a mixture thereof.
In an embodiment, the support layer 830 may be formed in the form of a mesh including a plurality of through holes. In the above embodiment, even when the electrically insulating material is injected into the housing space 110, the support layer 830 may be prevented from undergoing unintended displacement, and the shield unit 500 may be maintained in a stably coupled state.
The support layer 830 may be formed in any shape capable of supporting the housing shield member 520. In an embodiment, the support layer 830 may be formed by being processed using a separate mold or the like. In another embodiment, the support layer 830 may be formed in a coating form applied to the housing inner surface 120.
The support layer 830 may be formed in a shape corresponding to the housing space 110 and the shapes of the housing opening 130 and the bobbin support portion 140 located in the housing space 110.
In the illustrated embodiment, the support layer 830 includes a first support layer 831, a second support layer 832, and a third support layer 833.
The first support layer 831 forms a part of the support layer 830. The first support layer 831 is in contact with the housing inner surface 120 and supports the housing shield member 520 coupled to the housing inner surface 120.
The first support layer 831 may be formed to correspond to the shape of the housing space 110. In the illustrated embodiment, the first support layer 831 includes five surfaces corresponding to the first to fifth housing inner surfaces 121, 122, 123, 124, and 125. In addition, an opening corresponding to the housing opening 130 is formed to penetrate one side corresponding to the second housing inner surface 122, namely, the front side in the illustrated embodiment.
That is, the first support layer 831 is formed to surround the housing inner surface 120.
The second support layer 832 forms another portion of the support layer 830. The second support layer 832 comes into contact with the bobbin support portion 140 and is configured to surround the bobbin support portion 140. In an embodiment in which the housing shield member 520 is provided on the bobbin support portion 140, the second support layer 832 may support the housing shield member 520 coupled to the bobbin support portion 140.
The second support layer 832 may be formed to correspond to the shapes of the bobbin support portion 140 and the core receiving portion 150. In the illustrated embodiment, the second support layer 832 includes a pair of four surfaces that surround respective outer surfaces of the first and second bobbin support portions 141 and 142. Each pair of four surfaces is configured to surround the outer surfaces of the first and second bobbin support portions 141 and 142.
In addition, a hollow portion that is open in the height direction-namely, the vertical direction in the illustrated embodiment-is formed inside the four surfaces of the second support layer 832. The first and second bobbin support portions 141 and 142 may be inserted into the hollow portion.
That is, the second support layer 832 is formed to surround the outer surface of the bobbin support portion 140.
The third support layer 833 forms another portion of the support layer 830. The third support layer 833 is coupled to the bobbin support portion 140 and is configured to surround the bobbin support portion 140. In the illustrated embodiment, the third support layer 833 is configured to cover the upper end of the bobbin support portion 140.
The third support layer 833 may be formed to correspond to the shapes of the bobbin support portion 140 and the core receiving portion 150. In the illustrated embodiment, the third support layer 833 is provided in the form of a rectangular ring having a rectangular perimeter and a hollow formed therein so as to respectively surround the upper ends of the bobbin support portions 140.
A plurality of third support layers 833 may be provided. The plurality of third support layers 833 may respectively surround the plurality of bobbin support portions 140. In the illustrated embodiment, a pair of third support layers 833 is provided to respectively cover the upper ends of the first and second bobbin support portions 141 and 142.
The first support layer 831, the second support layer 832, and the third support layer 833 may be integrally formed or separately formed and then joined together. In either case, it is sufficient that the first support layer 831, the second support layer 832, and the third support layer 833 are continuously connected and coupled to the housing 100.
In addition, the first to third support layers 831, 832, and 833 may be provided independently. In the above embodiment, one or more of the first to third support layers 831, 832, and 833 may be provided.
In an embodiment, only the first support layer 831 may be provided and may be arranged to surround the housing shield member 520 coupled to the housing inner surface 120 from the inner side. In the above embodiment, the first support layer 831 may be formed to surround one or more of the first to fifth housing inner surfaces 121, 122, 123, 124, and 125.
For example, the first support layer 831 may be formed only on the first housing inner surface 121, which forms the lower side of the housing inner surface 120, or may be formed on the second to fifth housing inner surfaces 122, 123, 124, and 125 excluding the first housing inner surface 121.
That is, the first support layer 831 may be provided in any form capable of supporting the housing shield member 520.
In another embodiment, only the second support layer 832 may be provided and configured to surround the surface of the bobbin support portion 140. In the illustrated embodiment, a separate member for supporting the housing shield member 520 coupled to the second to fifth housing inner surfaces 122, 123, 124, and 125 may be provided.
Referring to FIG. 16, a transformer 10 according to another embodiment of the present invention is illustrated as an example.
In the illustrated embodiment, the semiconductive layer S.C is applied to the entire inner surface of the housing 100. In addition, the semiconductive layer S.C is applied to a portion of the inner surface of the bushing 600 facing the housing 100-specifically, a rear portion in the illustrated embodiment.
The semiconductive layer S.C applied to the inner surface of the bushing 600 may be in contact with the bushing shield member 510 of the shield unit 500. Accordingly, the semiconductive layer S.C applied to the inner surface of the bushing 600 may serve to alleviate the electric field and prevent dielectric breakdown in cooperation with the bushing shield member 510.
Meanwhile, the semiconductive layer S.C applied to the inner surface of the housing 100 may be connected to the semiconductive layer S.C applied to the inner surface of the bushing 600. Accordingly, the semiconductive layer S.C applied to the inner surface of the housing 100 may serve to alleviate the electric field and prevent dielectric breakdown in cooperation with the semiconductive layer S.C applied to the inner surface of the bushing 600.
In the present embodiment, the area of the semiconductive layer S.C applied to the inner surface of the housing 100 may be formed to be larger than that in the embodiment in which the housing shield member 520 is provided. In an embodiment, the area of the semiconductive layer S.C applied to the inner surface of the housing 100 may be equal to the entire area of the inner surface of the housing 100.
Specifically, the area of the semiconductive layer S.C may be equal to the sum of the areas of the first to fifth housing inner surfaces 121, 122, 123, 124, and 125 and the sum of the outer surface areas of the first and second bobbin support portions 141 and 142. In other words, the semiconductive layer S.C may be applied to the entire inner surface of the housing 100 and the entire outer surface of the bobbin support portion 140.
In the illustrated embodiment, the housing shield member 520 is not required inside the housing 100 to be electrically connected to the semiconductive layer S.C. Accordingly, the assembly and manufacturing processes may be simplified compared to the above-described embodiment.
In the illustrated embodiment, since the semiconductive layer S.C is formed on the inner surface of the housing 100 and the inner surface of the bushing 600, the semiconductive layer S.C is not exposed to the outside of the transformer 10. Accordingly, the semiconductive layer S.C can perform the functions of electric field mitigation and dielectric breakdown prevention without the housing shield member 520, while remaining protected from damage caused by external environments.

3. Description of Method for Manufacturing the Transformer 10 According to an Embodiment of the Present Invention

Referring to FIGS. 17 to 28, a method for manufacturing the transformer 10 according to an embodiment of the present invention is illustrated by way of example.
The transformer 10 according to an embodiment of the present invention may be manufactured by molding the housing 100 and the bushing 600, which form the external shape thereof, using a mold M. In this case, the housing 100 and the bushing 600 may be formed by injecting an electrically insulating material such as epoxy.
In addition, after other components of the transformer 10 are placed in the internal spaces of the housing 100 and the bushing 600, an electrically insulating material may be injected into the internal spaces to secure the components and maintain insulation. That is, the molded housing 100 and bushing 600 may be further utilized as a mold for assembling and securing the placed components.
In an embodiment, a semiconductive layer S.C may be formed on the inner surface of the housing 100 or the bushing 600. As the semiconductive layer S.C is formed on the inner surface of the housing 100 or the bushing 600, damage to the semiconductive layer S.C caused by the external environment can be prevented. Accordingly, degradation in insulation performance and electric field mitigation performance due to damage to the semiconductive layer S.C can be prevented.
In an embodiment, a housing shield member 520 may be provided inside the housing 100. The housing shield member 520 may be electrically connectable to both the formed semiconductive layer S.C and an external ground, and may be configured to mitigate the generated electric field. Accordingly, even when the transformer 10 operates, electric field concentration, dielectric breakdown, and partial discharge phenomena can be minimized.
In an embodiment, the semiconductive layer S.C may be formed to cover less than 90% of the surface area of the housing 100. Even in such a case, sufficient insulation performance and electric field mitigation performance can be ensured by the housing shield member 520 that is arranged in contact with the semiconductive layer S.C.
Hereinafter, a method for manufacturing the transformer 10 according to an embodiment of the present invention will be described in detail with reference to FIGS. 17 to 28.
Referring to FIG. 17, the method for manufacturing the transformer 10 according to the illustrated embodiment includes a step (S100) of fabricating the housing 100, a step (S200) of applying a semiconductive layer S.C to the interior of the housing 100, a step (S300) of coupling the first winding unit 300 to the housing 100, a step (S400) of injecting an electrically insulating material into the interior of the housing 100, and a step (S500) of coupling the second winding unit 400 to the housing 100.
Referring to FIGS. 18 and 19, a detailed flow and procedure of the step (S100) of fabricating the housing 100 is illustrated by way of example. The step (S100) is a step in which the housing 100 is fabricated by injecting an electrically insulating material into a mold M.
First, the mold M is fabricated (S110). The mold M may be formed in a shape corresponding to the shape in which the housing 100 and the bushing 600 are combined.
An electrically insulating material is injected into the mold M, and the housing 100 and the bushing 600 are molded (S120). In the present embodiment, it will be understood that the housing 100 and the bushing 600 are integrally formed. In an embodiment, the electrically insulating material may be any material capable of being molded, such as a synthetic resin material such as epoxy or silicone-based material, or an insulating oil material such as mineral oil, alkylbenzene, polybutene, alkylnaphthalene, alkyldiphenylethane, silicone oil, a mixture of mineral oil and alkylbenzene, vegetable oil such as natural esters, or a mixture thereof.
Referring to FIGS. 20 and 21, a detailed flow and process of the step S200 of applying the semiconductive layer S.C to the interior of the housing 100 is illustrated as an example. The step S200 is a step of forming the semiconductive layer S.C on the inner surface of the fabricated housing 100.
A semiconductive layer S.C is applied to the housing inner surface 120, which surrounds the housing space 110 formed inside the housing 100 in a radially outward direction (S210). At this time, the area of the semiconductive layer S.C formed on the housing first inner surface 121 may be equal to the area of the first housing inner surface 121. In addition, the area of the semiconductive layer S.C formed on the second to fifth housing inner surfaces 122, 123, 124, and 125 may be smaller than the combined area of the second to fifth housing inner surfaces 122, 123, 124, and 125.
In an embodiment, the total area of the semiconductive layer S.C may be maintained to be less than 90% of the total area of the housing inner surface 120.
In addition, a semiconductive layer S.C is applied to the surface of the bobbin support portion 140, which surrounds the housing space 110 formed inside the housing 100 in a radially inward direction (S220). It will be understood that this step (S220) corresponds to an embodiment in which the semiconductive layer S.C is also formed on the bobbin support portion 140.
At this time, the area of the semiconductive layer S.C formed on the surface of the bobbin support portion 140 is equal to or less than the area of the surface of the bobbin support portion 140. In an embodiment, the total area of the semiconductive layer S.C formed on the inner surface 120 of the housing and the bobbin support portion 140 may be maintained to be less than 90% of the total area of the housing inner surface 120 and the bobbin support portion 140.
At this time, the semiconductive layer S.C may also be partially applied to the bushing body 610. Accordingly, one portion of the bushing shield member 510 accommodated in the bushing space 620 may be in contact with the semiconductive layer S.C, and another portion of the bushing shield member 510 may be spaced apart from the semiconductive layer S.C.
Meanwhile, the semiconductive layer S.C may be applied to the inner surface of the housing 100 or the bushing body 610 in various ways. For example, the semiconductive layer S.C may be applied to the inner surface of the housing 100 or the bushing body 610 by affixing, electroplating, evaporating, pouring, or spraying or the like.
Meanwhile, as described above, in the transformer 10 according to another embodiment of the present invention illustrated in FIG. 16, the semiconductive layer S.C may be applied over the entire housing inner surface 120. In the above embodiment, the application area of the semiconductive layer S.C may be equal to the sum of the area of the housing inner surface 120 and the area of the outer surface of the bobbin support portion 140, as previously described.
Referring to FIGS. 22 to 24, a detailed flow and procedure of step S300, in which the first winding unit 300 is coupled to the housing 100, is illustrated by way of example. Step S300 is a step in which the first winding unit 300 is coupled to the interior of the housing 100 having the semiconductive layer S.C formed thereon, and the shield unit 500 is disposed to mitigate an electric field generated by the first winding unit 300 or the second winding unit 400.
The first winding unit 300 is manufactured by winding the first coil 310 around the first bobbin 320 (S310). As described above, a plurality of first winding units 300 may be provided and may be respectively positioned adjacent to different locations of the core unit 200.
The first bobbin 320 is coupled to the bobbin support portion 140 formed in the housing 100 (S320). As described above, the bobbin support portion 140 includes a plurality of components, including the first and second bobbin support portions 141 and 142. The first and second bobbin support portions 141 and 142 are respectively inserted into and coupled to the first bobbin space 321 formed to penetrate the interior of the first bobbin 320. Accordingly, the plurality of first winding units 300 are spaced apart from each other.
The bushing shield member 510 is disposed in a bushing space 620 formed inside the bushing 600 coupled to the housing 100 (S330). At this time, the bushing shield member 510 may be partially overlapped with the semiconductive layer S.C formed on the inner circumferential surface of the bushing body 610. That is, one side of the bushing shield member 510 facing the housing 100 may overlap the semiconductive layer S.C, while the opposite side may be spaced apart from the semiconductive layer S.C.
In addition, the bushing shield member 510 is disposed to be exposed to the housing space 110 through the housing opening 130.
The housing shield member 520 is disposed to be in contact with the semiconductive layer S.C applied to the interior of the housing 100 and to be electrically connectable to the bushing shield member 510 (S340). The housing shield member 520 extends along the second to fifth housing inner surfaces 122, 123, 124, and 125, which surround the housing space 110 from the outside.
At this time, the housing shield member 520 is disposed to be in contact with the semiconductive layer S.C formed on the second to fifth housing inner surfaces 122, 123, 124, and 125, and may be electrically connected to the semiconductive layer S.C.
In addition, among the housing shield members 520, the housing shield member 520 disposed on the second housing inner surface 122 may be electrically connected to the bushing shield member 510. Accordingly, the housing shield member 520 may be electrically connected to the bushing shield member 510 and an external ground.
Meanwhile, as shown in FIG. 16, in an embodiment in which the semiconductive layer S.C is applied to the entire housing inner surface 120 and the entire outer surface of the bobbin support portion 140, step S340 may be omitted. That is, in the above embodiment, since the semiconductive layer S.C applied to the entire housing inner surface 120 and the entire outer surface of the bobbin support portion 140 is connected to the semiconductive layer S.C applied to the inner surface of the bushing 600, the effects of electric field mitigation and dielectric breakdown prevention may be achieved.
The sequence of performing step S300, in which the first winding unit 300 is coupled to the interior of the housing 100 having the semiconductive layer S.C formed thereon and the shield unit 500 is disposed to mitigate the electric field generated by the first winding unit 300 or the second winding unit 400, may be varied.
That is, in the illustrated embodiment, it is assumed that the first winding unit 300 is manufactured first, and then the manufactured first winding unit 300 is coupled to the shield unit 500 and the housing 100. Alternatively, the sequence of the detailed steps S310, S320, S330, and S340 of step S300 may be varied, such as by coupling the shield unit 500 to the housing 100 first, followed by the manufacture and coupling of the first winding unit 300.
Referring to FIGS. 25 to 26, a detailed flow and procedure of step S400, in which the electrically insulating material is injected into the housing 100, is illustrated as an example. Step S400 is a step in which, after the housing space 110 is sealed, an electrically insulating material is injected so that each component accommodated in the housing space 110 is fixed.
First, the first housing 101 and the second housing 102 are coupled together to seal the housing space 110 formed therein (S410). At this time, the bobbin support portions 140 respectively formed in the first housing 101 and the second housing 102 are also aligned and arranged, thereby blocking the fluid communication between the housing space 110 and the core receiving portion 150.
Now, an electrically insulating material is injected through the housing fluid communication portion 160, which is formed on one side of the first housing 101 and the second housing 102 and provides fluid communication between the housing space 110 and the outside (S420). In an embodiment, the electrically insulating material may be made of a synthetic resin material such as epoxy or a silicone-based material. In another embodiment, the electrically insulating material may be provided as an insulating oil material such as mineral oil, alkylbenzene, polybutene, alkylated naphthalene, alkylated diphenyl ethane, silicone oil, a mixed oil of mineral oil and alkylbenzene, or a vegetable oil such as natural ester, or a mixture thereof, as described above.
Next, the housing fluid communication portion 160 is closed, thereby sealing the housing space 110 (S430). In an embodiment, the housing fluid communication portion 160 may be removed, and a through hole formed in the third housing inner surface 123 may be closed to carry out step S430.
Also, although not illustrated as a step, the bushing cover 630 may be coupled to the bushing body 610 to seal the bushing space 620. Accordingly, the bushing space 620 and the housing space 110 in fluid communication therewith are sealed, thereby blocking fluid communication with the outside.
Referring to FIGS. 27 to 28, a detailed flow and procedure of step S500, in which the second winding unit 400 is coupled to the housing 100, is illustrated by way of example. Step S500 is a step in which the second winding unit 400 and the core unit 200 are coupled to the housing 100, thereby completing the transformer 10.
The second winding unit 400 is manufactured by winding the second coil 410 around the second bobbin 420 (S510). As described above, a plurality of second winding units 400 may be provided and may be respectively positioned adjacent to different locations of the core unit 200.
The manufactured second winding unit 400 is disposed to cover the housing 100 (S520). In this case, the second winding units 400 may be provided in a plurality of pairs, each pair including two units. One of the pairs of the plurality of second winding units 400 may be disposed to cover the first housing 101 from the outside. Another pair of the plurality of second winding units 400 may be disposed to cover the second housing 102 from the outside.
In this case, the second bobbin space 421 formed inside the second winding unit 400 may be disposed to overlap the first core receiving portion 151 and the first bobbin space 321.
Now, the core unit 200 is coupled to penetrate through the first bobbin space 321 formed inside the first bobbin 320 and the second bobbin space 421 formed inside the second bobbin 420 (S530). In this case, the first bobbin space 321 is coupled to penetrate through the bobbin support portion 140, and a core receiving portion 150 is formed inside the bobbin support portion 140.
That is, the bobbin support portion 140, the core receiving portion 150, the first bobbin space 321, and the second bobbin space 421 are arranged to overlap with one another.
The core unit 200 includes a first core unit 201 coupled to the first housing 101 and a second core unit 202 coupled to the second housing 102.
The first core unit 201 is coupled to the first housing 101 and to the first winding unit 300 and the second winding unit 400 coupled thereto. The second core unit 202 is coupled to the second housing 102 and to the first winding unit 300 and the second winding unit 400 coupled thereto. The inserted first and second core units 201 and 202 may be in contact with each other.
In addition, although not illustrated as a separate step, a step of coupling the coupling frame 700 to the housing 100 while covering the core unit 200 and the second winding unit 400 may further be included.

Although exemplary embodiments of the present invention have been described, the spirit of the present invention is not limited to the embodiments set forth herein. Those of ordinary skill in the art who understand the spirit of the present invention may easily propose other embodiments through supplement, change, removal, addition, etc. of elements within the scope of the same inventive concept, but such embodiments will also fall within the scope of the present invention.

10:	transformer	100:	housing
101:	first housing	102:	second housing
110:	housing space	120:	housing inner surface
121:	first housing inner surface	122:	second housing inner surface
123:	third housing inner surface	124:	fourth housing inner surface
125:	fifth housing inner surface	130:	housing opening
140:	bobbin support portion	141:	first bobbin support portion
142:	second bobbin support portion	150 :	core receiving portion
151:	first core receiving portion	152:	second core receiving portion
160:	housing fluid communication portion	200:	core unit
201:	first core unit	202:	second core unit
300:	first winding unit	310:	first coil
320:	first bobbin	321:	irst bobbin space
400:	second winding unit	410:	second coil
420:	second bobbin	421 :	second bobbin space
500:	shield unit	510 :	bushing shield member
520:	housing shield member	600 :	bushing
610:	bushing body	611 :	first bushing body
612:	second bushing body	620 :	bushing space
630:	bushing cover	700 :	coupling frame
710:	first coupling frame	720 :	second coupling frame
800:	shield member coupling portion	810:	accommodating groove
820:	support member	830:	support layer
831:	first support layer	832:	second support layer
833:	third support layer	S.C:	semiconductive layer
M:	mold

Claims

A transformer comprising:
a housing with a housing space formed therein;

a first winding unit which is electrically connectable to an external power source or load and is accommodated in the housing space;

a shield unit which is accommodated in the housing space spaced apart from the first winding unit and is electrically connectable to ground; and a semiconductive layer partially covering a surface surrounding the housing space,

wherein the semiconductive layer is formed to have an area smaller than a predetermined ratio of an entire area of the surface surrounding the housing space, and

wherein the shield unit is positioned in contact with the semiconductive layer in the housing space, and

the semiconductive layers respectively formed on a plurality of the surfaces surrounding the housing space are continuous with each other and are electrically connectable to the shield unit.
The transformer of claim 1,
further comprising a bushing coupled to the housing and having a bushing space formed therein that is in fluid communication with the housing space,

wherein the shield unit comprises:
a bushing shield member positioned in the bushing space and electrically connectable to the ground; and

a housing shield member coupled to the surface surrounding the housing space and electrically connectable to the bushing shield member.
The transformer of claim 2,
wherein the semiconductive layer is further formed on an inner surface of the bushing that surrounds the bushing space, such that the semiconductive layer is continuous with the semiconductive layer formed on the surface surrounding the housing space, and

wherein the bushing shield member extends in one direction in which the bushing extends, such that one end of the bushing shield member in the extending direction is positioned to overlap the inner surface of the bushing, and the other end in the extending direction is positioned to be spaced apart from the semiconductive layer.
The transformer of claim 2,
wherein the semiconductive layer is further formed on an inner surface of the bushing that surrounds the bushing space, such that the semiconductive layer is continuous with the semiconductive layer formed on the surface surrounding the housing space,

wherein the bushing shield member extends in one direction in which the bushing extends, and a point between both ends of the bushing shield member in the extending direction is electrically connectable to the ground, and

wherein the semiconductive layer is formed such that a boundary thereof is located between one end of the bushing shield member, which faces away from the housing, and the point.
The transformer of claim 2,
wherein the housing comprises:
a first housing inner surface configured to support the first winding unit;

a second housing inner surface and a third housing inner surface, each extending in one direction, continuously connected to the first housing inner surface, and disposed to face each other with the housing space interposed therebetween; and

a fourth housing inner surface and a fifth housing inner surface, each extending in another direction, continuously connected to the first to third housing inner surfaces, and disposed to face each other with the housing space interposed therebetween,

wherein the semiconductive layer is formed to at least partially cover each of the first to fifth housing inner surfaces.
The transformer of claim 5,
wherein an area of the semiconductive layer formed on the first housing inner surface is equal to or less than an area of the first housing inner surface, and

an area of the semiconductive layer formed on the second to fifth housing inner surfaces is less than a sum of areas of the second to fifth housing inner surfaces.
The transformer of claim 5,
wherein the housing shield member extends along the second to fifth housing inner surfaces so as to surround the housing space, and is spaced apart by a predetermined distance from one end, opposite to the first housing inner surface, among ends in a height direction of the second to fifth housing inner surfaces, and

wherein the semiconductive layer is formed from the housing shield member to the first housing inner surface.
The transformer of claim 6, wherein a total area of the semiconductive layer formed on the first to fifth housing inner surfaces is less than 90% of a total area of the first to fifth housing inner surfaces.
The transformer of claim 5,
wherein the housing comprises:
a bobbin support portion that extends in a height direction from the first housing inner surface and is spaced apart from the second to fifth housing inner surfaces; and

a core receiving portion that is formed to penetrate the bobbin support portion and receives a core unit, while fluid communication with the housing space is blocked, and

wherein the first winding unit comprises:
a first bobbin in which a first bobbin space is formed to penetrate the first bobbin and be coupled to the bobbin support portion; and

a first coil wound around the first bobbin and electrically connectable to an external power source or load.
The transformer of claim 9,
wherein the semiconductive layer is formed to cover a surface of the bobbin support portion that faces the housing space,

a surface area of the semiconductive layer formed on the surface of the bobbin support portion is equal to or less than a surface area of the surface of the bobbin support portion, and

the housing shield member is disposed on the surface of the bobbin support portion to be in contact with the semiconductive layer.
The transformer of claim 10,
wherein the housing shield member extends along the surface of the bobbin support portion to surround the core receiving portion, and is spaced apart by a predetermined distance from one end of the surface of the bobbin support portion in a height direction, the one end being opposite to the first housing inner surface, and

the semiconductive layer is formed on the surface of the bobbin support portion from the housing shield member to the first housing inner surface.
A transformer comprising:
a housing with a housing space formed therein;

a bushing coupled to the housing and having a bushing space formed therein, the bushing space being in fluid communication with the housing space;

a shield unit accommodated in the bushing space and electrically connectable to ground; and

a semiconductive layer formed to at least partially cover a surface surrounding the housing space and a surface surrounding the bushing space, respectively,

wherein the semiconductive layer is formed to cover the entire surface surrounding the housing space, and to cover a portion of the surface surrounding the bushing space that is in contact with the shield unit, such that the semiconductive layer is in contact with the shield unit.
The transformer of claim 12, wherein a portion of the semiconductive layer that covers the surface surrounding the bushing space and a portion that covers the surface surrounding the housing space are continuous with each other.
The transformer of claim 12,
wherein the housing comprises:
a bobbin support portion disposed in the housing space and extending in a height direction from a surface that surrounds the housing space on one side in the height direction, and

wherein the semiconductive layer is formed to entirely cover a surface of the bobbin support portion that faces the housing space.