Common mode choke device

Abstract

A common mode choke device is provided with a first common mode choke and a second common mode choke, the first common mode choke and the second common mode choke are arranged in parallel such that annular iron cores are coaxial, and a pair of opposing metal rings formed as annular metal plates are attached to opposing annular surfaces of the first common mode choke and the second common mode choke. A pair of opposed metal rings is connected to a reference potential. The pair of opposing metal rings function as a capacitance of a parasitic capacitance corresponding to the area of the opposing surfaces and the distance between the opposing surfaces, and thus the common mode choke device functions as an LCL filter.

Description

Technical Field

[0001] This invention relates to a common-mode choke device. Background Technology

[0002] Conventionally, a technique has been proposed that reduces the impact of noise on the driven device by reducing common-mode noise, normal-mode noise, and reflected noise in a power supply system (see, for example, Japanese Patent Application Laid-Open No. 2023-069646). Sometimes, magnetic flux is generated within the core of a common-mode choke due to noise. Furthermore, this magnetic flux sometimes induces an electromotive force in the power line, and the resulting current flow becomes reflected noise in the power line. In this technique, reflected noise is reduced by the winding on the core of the common-mode choke and the resistor connected to that winding. Moreover, even when noise reflected by the driven device passes through the common-mode choke, the CR circuit can convert the reflected noise into heat energy and dissipate it using the resistive component of the resistor. Summary of the Invention

[0003] Common-mode chokes are used as LC or LCL filters to counteract noise by connecting Y capacitors. In this case, the magnetic core must be large-scaled or a high-cost magnetic core with high permeability must be used, with concerns about increased size or weight and increased cost.

[0004] The main purpose of the common mode choke device of the present invention is to achieve miniaturization and weight reduction.

[0005] To achieve the above-mentioned main objectives, the common mode choke device of the present invention employs the following method.

[0006] The common mode choke device of the present invention is a common mode choke device having a first common mode choke and a second common mode choke, characterized in that the first common mode choke and the second common mode choke are arranged in parallel with an annular iron core coaxially, and a pair of opposing metal rings formed as annular metal plates are installed on the opposing annular surfaces of the first common mode choke and the second common mode choke, and the pair of opposing metal rings are connected to a reference potential.

[0007] The common-mode choke device of the present invention includes a first common-mode choke and a second common-mode choke. The first and second common-mode chokes are arranged in parallel with their annular cores coaxially. A pair of opposing metal rings are mounted on the opposing annular surfaces of the first and second common-mode chokes. The pair of opposing metal rings form annular metal plates. The pair of opposing metal rings are connected to a reference potential. If the area of ​​the opposing surfaces of the pair of opposing metal rings is S, the distance between the opposing surfaces of the pair of opposing metal rings is d, and the dielectric constant is ε, then the pair of opposing metal rings function as a parasitic capacitance C, which is calculated by C = ε·S / d. Therefore, an LCL filter can be constructed from the first common-mode choke, the second common-mode choke, and the pair of opposing metal rings, reducing the number of parts or cost. As a result, miniaturization and weight reduction of the common-mode choke device can be achieved.

[0008] In the common-mode choke device of the present invention, the pair of opposing metal rings can be installed on the outer side of the windings of the first common-mode choke and the second common-mode choke. Alternatively, the pair of opposing metal rings can be installed on the inner side of the windings of the first common-mode choke and the second common-mode choke. Attached Figure Description

[0009] Hereinafter, the features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described with reference to the accompanying drawings, in which the same reference numerals denote the same elements, and wherein: Figure 1 This is a schematic configuration diagram showing the structure of a common mode choke device 20 as an embodiment of the present invention.

[0010] Figure 2 This is a schematic configuration diagram showing the configuration of the common mode choke device 120 of the comparative example. Detailed Implementation

[0011] Next, the methods (implementation methods) for carrying out this disclosure will be described. Figure 1 This is a schematic configuration diagram showing the structure of a common mode choke device 20 as an embodiment of the present invention. As shown, the common mode choke device 20 includes a first common mode choke 24, a second common mode choke 26, a first opposing metal ring 34, and a second opposing metal ring 36.

[0012] The first common-mode choke 24 and the second common-mode choke 26 constitute a known common-mode choke. Specifically, windings 22a, 28a and 22b, 28b are wound on a ring-shaped iron core formed of a soft magnetic material such as nanocrystalline alloy or ferrite. The windings 22a and 22b of the first common-mode choke 24 are connected to the windings 28a and 28b of the second common-mode choke 26. The first common-mode choke 24 and the second common-mode choke 26 are arranged in parallel in a coaxial manner.

[0013] The first opposing metal ring 34 and the second opposing metal ring 36 are formed from energized metal plates in the same manner as the core of the first common-mode choke 24, into thin, circular rings. The first opposing metal ring 34 is mounted on the surface of the first common-mode choke 24 opposite to the second common-mode choke 26. The second opposing metal ring 36 is mounted on the surface of the second common-mode choke 26 opposite to the first common-mode choke 24. That is, the first opposing metal ring 34 and the second opposing metal ring 36 are mounted on the opposing surfaces of the first common-mode choke 24 and the second common-mode choke 26. Furthermore, the first opposing metal ring 34 and the second opposing metal ring 36 are connected to a grounded reference potential 40.

[0014] Now, consider Figure 2 The comparative example illustrated is a common-mode choke device 120. The comparative example common-mode choke device 120 is a known LCL filter. Specifically, the first common-mode choke 124 and the second common-mode choke 126 are connected via their windings 122a, 122b and windings 128a, 128b. Furthermore, the connection point of windings 122a, 122b and windings 128a, 128b is connected to a reference potential 140 via capacitors 134, 136. The reference potential 140 is grounded. Figure 1 In the common-mode choke device 20 of the illustrated embodiment, the area of ​​the opposing surfaces of the first opposing metal ring 34 and the second opposing metal ring 36 is set as S, the distance between the opposing surfaces is set as d, and the dielectric constant is set as ε. The common-mode choke device 20 functions as a capacitor for a parasitic capacitance C, which is calculated using C = ε·S / d. Figure 2 Similarly, the common-mode choke device 120 of the comparative example illustrated functions as an LCL filter. In the common-mode choke device 20 of the embodiment, no capacitor is required, thus reducing the number of parts or cost. As a result, miniaturization and weight reduction of the common-mode choke device are achieved.

[0015] In the common-mode choke device 20 described above, the first common-mode choke 24 and the second common-mode choke 26 are arranged in parallel coaxially. A first opposing metal ring 34 and a second opposing metal ring 36, which are also constructed as thin plates in annular shape similar to the core of the first common-mode choke 24, are mounted on the opposing surfaces of the first common-mode choke 24 and the second common-mode choke 26. The first opposing metal ring 34 and the second opposing metal ring 36 are connected to a grounded reference potential 40. Thus, the common-mode choke device 20 can function as an LCL filter. No capacitor is required, thereby reducing the number of parts or cost. As a result, miniaturization and weight reduction of the common-mode choke device are achieved.

[0016] In the common-mode choke device 20 of the embodiment, a first common-mode choke 24 with windings 22a and 22b and a second common-mode choke 26 with windings 28a and 28b are coaxially parallel to each other. A first opposing metal ring 34 and a second opposing metal ring 36 are mounted on their opposing surfaces. However, another configuration is also possible. Specifically, a first common-mode choke formed by windings 22a and 22b with the first opposing metal ring 34 mounted on the core and a second common-mode choke formed by windings 28a and 28b with the second opposing metal ring 36 mounted on the core are also prepared. Alternatively, the first and second common-mode chokes can be arranged coaxially parallel with the first opposing metal ring 34 and the second opposing metal ring 36 facing each other.

[0017] The correspondence between the main elements of the implementation method and the main elements of the invention described in the means for solving the problem section will be explained. In the implementation method, the first common mode choke 24 is equivalent to "first common mode choke", the second common mode choke 26 is equivalent to "second common mode choke", and the first opposing metal ring 34 and the second opposing metal ring 36 are equivalent to "a pair of opposing metal rings".

[0018] Furthermore, the correspondence between the main elements of the implementation method and the main elements of the invention described in the "Means for Solving the Problem" column is one example used to specifically explain how the implementation method is used to carry out the invention described in the "Means for Solving the Problem" column. These correspondences are not limited to the elements of the invention described in the "Means for Solving the Problem" column. That is, the interpretation of the invention described in the "Means for Solving the Problem" column should be based on the description in that column; the implementation method is merely a specific example of the invention described in the "Means for Solving the Problem" column.

[0019] The present disclosure has been described above using embodiments, but the present disclosure is not limited to such embodiments. Of course, it can be implemented in various ways without departing from the spirit of the present disclosure.

[0020] This invention can be used in industries such as the manufacturing of common mode choke devices.

Claims

1. A common-mode choke device, comprising a first common-mode choke and a second common-mode choke, characterized in that, The first common-mode choke and the second common-mode choke are arranged in parallel with their annular cores coaxial. On the opposing annular surfaces of the first common-mode choke and the second common-mode choke, a pair of opposing metal rings formed as annular metal plates are installed. The pair of opposing metal rings are connected to a reference potential.

2. The common-mode choke device according to claim 1, characterized in that, The pair of opposing metal rings are installed on the outside of the windings of the first common mode choke and the second common mode choke.

3. The common-mode choke device according to claim 1, characterized in that, The pair of opposing metal rings are installed on the inner side of the windings of the first common mode choke and the second common mode choke.

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