JP-2026076023-A - Three-phase composite common inductor

JP2026076023AJP 2026076023 AJP2026076023 AJP 2026076023AJP-2026076023-A

Abstract

[Problem] As a result, the present invention provides a three-phase composite common inductor that can suppress the occurrence of magnetic saturation even in high-current applications. [Solution] A three-phase composite common inductor 1 that acts as a common inductance for common current and as a normal inductance for normal current, comprising a first core 2, a second core 3, and a U-phase coil 4U, a V-phase coil 4V, and a W-phase coil 4W wound around the first core 2, wherein the second core 3 is made of a material with lower magnetic permeability than the first core 2. [Selection Diagram] Figure 4

Inventors

紹革良

Assignees

Ｍａｇｒｏｏｔｓテクノロジー株式会社

Dates

Publication Date: 20260511
Application Date: 20241023

Claims (7)

A three-phase composite common inductor that acts as a common inductance for common current and as a normal inductance for normal current, The first core and The second core, The first core comprises a first phase coil, a second phase coil, and a third phase coil, The first core is, The first and second legs are arranged in parallel to each other, A first connecting portion that connects one end of the first leg portion and the second leg portion, It comprises a second connecting portion that connects the other ends of the first leg portion and the second leg portion, At least one of the first leg portion and the second leg portion is wound with the first phase coil, the second phase coil, and the third phase coil in order from one end to the other end. The second core comprises a third leg portion and a fourth leg portion that are arranged in parallel with each other and connect the intermediate portions of the first leg portion and the second leg portion, The first phase coil, the second phase coil, and the third phase coil are edgewise coils made by winding flat wire at a right angle. The first phase coil is wound around at least one of the first leg portion and the second leg portion between the first connecting portion and the third leg portion. The second phase coil is wound around at least one of the first leg and the second leg between the third leg and the fourth leg. The third phase coil is wound around at least one of the first leg and the second leg between the fourth leg and the second connecting portion. A three-phase composite common inductor characterized in that the second core is formed of a material with lower magnetic permeability than the first core.
The three-phase composite common inductor according to claim 1, characterized in that the first core is a ferrite core, and the second core is a dust core with a lower magnetic permeability than the ferrite core.
The three-phase composite common inductor according to claim 1, characterized in that the first core is formed by connecting two U-shaped cores.
The three-phase composite common inductor according to claim 1, characterized in that the first core is formed by connecting two U-shaped cores via two I-shaped cores.
The three-phase composite common inductor according to claim 4, characterized in that a gap is provided between the U-shaped core and the I-shaped core for adjusting the balance of the three-phase normal inductances.
The second core is, A first plate portion is arranged along the inner circumferential surface of the first leg portion, The device further comprises a second plate portion arranged along the inner circumferential surface of the second leg portion, One end of the third leg is connected to the first leg via the first plate, The other end of the third leg is connected to the second leg via the second plate, One end of the fourth leg is connected to the first leg via the first plate, The three-phase composite common inductor according to claim 1, characterized in that the other end of the fourth leg is connected to the second leg via the second plate.
The second core is, A first auxiliary leg is positioned along the side surface of the third leg and connects the intermediate side surfaces of the first and second legs, The three-phase composite common inductor according to claim 1, further comprising a second auxiliary leg positioned along the side surface of the fourth leg and connecting the intermediate side surfaces of the first leg and the second leg.

Description

This invention relates to a three-phase composite common inductor. Patent Document 1 discloses a three-phase composite common inductor (dual-mode choke coil) that acts as a common inductance (common-mode noise filter) for common currents and as a normal inductance (normal-mode noise filter) for normal currents. International Publication No. 2020/144795 This is a perspective view of a three-phase composite common inductor according to an embodiment of the present invention.(a) is a perspective view of the first core, (b) is a perspective view of the second core, and (c) is a perspective view showing the second core assembled to the first core.(a) is a perspective view of the U-phase coil, V-phase coil, and W-phase coil, and (b) is a perspective view of the bobbin.This diagram schematically shows the structure of a three-phase composite common inductor.(a) is a schematic diagram showing the basic structure of a three-phase composite common inductor, and (b) is the magnetic equivalent circuit of the three-phase composite common inductor.(a) is a diagram showing the flow of magnetic flux when a common current is input to a three-phase composite common inductor, and (b) is the magnetic equivalent circuit when a common current is input to a three-phase composite common inductor.This is a diagram illustrating the normal current input to a three-phase composite common inductor.(a) is a diagram showing the flow of magnetic flux when a normal current is input to a three-phase composite common inductor, and (b) is the magnetic equivalent circuit when a normal current is input to a three-phase composite common inductor.This figure schematically shows the structure of a three-phase composite common inductor according to the first modified example.(a) is a schematic diagram showing the core structure of a three-phase composite common inductor according to the second modified example, and (b) is a schematic diagram showing the core structure of a three-phase composite common inductor according to the third modified example. [Basic Configuration of a Three-Phase Composite Common Inductor] Embodiments of the present invention will be described below with reference to the drawings. In Figures 1 to 4, 1 is a three-phase composite common inductor, which acts as a common inductance with respect to common current and as a normal inductance with respect to normal current. For example, the three-phase composite common inductor 1 is used as a dual-mode noise filter to reduce common-mode noise and normal-mode noise in high-current applications such as high-capacity battery charging circuits, high-capacity power conditioner circuits, motor drive circuits for electric vehicles, and compressor drive circuits for hydrogen fuel cells. As shown in Figures 1 to 4, the three-phase composite common inductor 1 comprises a first core 2, a second core 3, a U-phase coil 4U, a V-phase coil 4V, a W-phase coil 4W, and a bobbin 5. The first core 2 comprises a first leg portion 21 and a second leg portion 22 arranged in parallel, a first connecting portion 23 connecting one end of the first leg portion 21 and the second leg portion 22, and a second connecting portion 24 connecting the other ends of the first leg portion 21 and the second leg portion 22. At least one of the first leg portion 21 and the second leg portion 22 is wound with a U-phase coil 4U, a V-phase coil 4V, and a W-phase coil 4W in order from one end to the other. The second core 3 includes a third leg portion 31 and a fourth leg portion 32 that are arranged in parallel and connect the intermediate portions of the first leg portion 21 and the second leg portion 22. The second core 3 is made of a material with lower magnetic permeability than the first core 2. The U-phase coil 4U is wound around at least one of the first leg portion 21 and the second leg portion 22 between the first connecting portion 23 and the third leg portion 31. The V-phase coil 4V is wound around at least one of the first leg portion 21 and the second leg portion 22 between the third leg portion 31 and the fourth leg portion 32. The W-phase coil 4W is wound around at least one of the first leg portion 21 and the second leg portion 22 between the fourth leg portion 32 and the second connecting portion 24. In this three-phase composite common inductor 1, the first leg 21, second leg 22, first connecting portion 23, and second connecting portion 24 of the first core 2 form a closed magnetic circuit for common inductance (hereinafter sometimes referred to as a common closed magnetic circuit). The first leg 21, second leg 22, and first connecting portion 23 of the first core 2 and the third leg 31 of the second core 3 form a closed magnetic circuit for U-phase normal inductance (hereinafter sometimes referred to as a U-phase normal closed magnetic circuit). The first leg 21 and second leg 22 of the first core 2 and the third leg 31 and fourth leg 32 of the second core 3 form a closed magnetic circuit for V-phase norm