US-12626858-B2 - Magnetically coupled reactor and boosting circuit

US12626858B2US 12626858 B2US12626858 B2US 12626858B2US-12626858-B2

Abstract

A reactor core of the magnetically coupled reactor includes a first outer core portion including two first leg portions extending in a first direction and a first base portion linking the two first leg portions, a second outer core portion including two second leg portions extending in the first direction and a second base portion linking the two second leg portions, and an intermediate core portion integrally extending continuously in the first direction and connecting the first leg portions and the second leg portions, in which a first connection portion, to which the first leg portions and the intermediate core portion are connected, is positioned in which a first coil portion is wound in the first direction, and a second connection portion, to which the second leg portions and the intermediate core portion are connected, is positioned in which the second coil portion is wound in the first direction.

Inventors

Inami Asai
Makoto Chiba
Yohei Inoue
Takeshi Yoshida

Assignees

KOMATSU LTD.

Dates

Publication Date: 20260512
Application Date: 20220707
Priority Date: 20210709

Claims (7)

1 . A magnetically coupled reactor comprising: a reactor core forming a closed magnetic circuit; a first coil portion wound around the reactor core in a split manner; and a second coil portion wound in a split manner at a position apart from the first coil portion in a first direction in the reactor core, wherein the reactor core includes a first outer core portion including two first leg portions extending in the first direction and a first base portion linking the two first leg portions on a first side in the first direction, a second outer core portion including two second leg portions extending in the first direction and a second base portion linking the two second leg portions on a second side in the first direction, and first and second intermediate core portions arranged side by side in a second direction intersecting the first direction and integrally extending continuously in the first direction to connect the first leg portions and the second leg portions, the first coil portion and the second coil portion are wound in a split manner to span at least across the two intermediate core portions arranged side by side in the second direction, a first connection portion defined between the first leg portions and the first intermediate core portion and positioned such that the first coil portion is wound in the first direction around at least the first connection portion, and a second connection portion defined between the second leg portions and the second intermediate core portion and positioned such that the second coil portion is wound in the first direction around at least the second connection portion.
2 . The magnetically coupled reactor according to claim 1 , further comprising a first separator configured to increase magnetic resistance and provided in at least one of the first connection portion and the second connection portion.
3 . The magnetically coupled reactor according to claim 1 , wherein, the first coil portion and the second coil portion are wound in directions such that a direction of magnetic flux generated in the closed magnetic circuit by the second coil portion is opposite to a direction of magnetic flux generated in the closed magnetic circuit by the first coil portion.
4 . The magnetically coupled reactor according to claim 1 , further comprising a second separator configured to increase magnetic resistance and provided in at least one of an area of the first leg portions of the first outer core portion in which the first coil portion is wound, and an area of the second leg portions of the second outer core portion in which the second coil portion is wound.
5 . A boosting circuit comprising: the magnetically coupled reactor according to claim 1 ; two-phase chopper circuits connected to the first coil portion and the second coil portion of the magnetically coupled reactor; and two smoothing capacitors connected between input terminals and output terminals.
6 . A magnetically coupled reactor comprising: a reactor core forming a closed magnetic circuit; a first coil portion wound around the reactor core in a split manner; and a second coil portion wound in a split manner at a position apart from the first coil portion in a first direction in the reactor core, wherein the reactor core includes a first outer core portion including two first leg portions, each of the two first leg portions including a first leg portion main body and a first split leg portion, extending in the first direction and a first base portion linking the two first leg portions on a first side in the first direction, a second outer core portion including two second leg portions, each of the two second leg portions including a second leg portion main body and a second split leg portion, extending in the first direction and a second base portion linking the two second leg portions on a second side in the first direction, and first and second intermediate core portions arranged side by side in a second direction intersecting the first direction and integrally extending continuously in the first direction to connect the first leg portions and the second leg portions, the first coil portion and the second coil portion are wound in a split manner to span at least across the two intermediate core portions arranged side by side in the second direction, a first connection portion defined between the first split leg portion and the first intermediate core portion and positioned such that the first coil portion is wound in the first direction around at least the first connection portion, and a third connection portion defined between the first leg portion main body and the first split leg portion and positioned such that the first coil portion is wound in the first direction around at least the third connection portion; a first separator configured to increase magnetic resistance and provided in the first connection portion, and a second separator configured to increase magnetic resistance and provided in the third connection portion.
7 . The magnetically coupled reactor according to claim 6 , further comprising: a second connection portion defined between the second split leg portion and the second intermediate core portion and positioned such that the second coil portion is wound in the first direction around at least the second connection portion, and a fourth connection portion defined between the second leg portion main body and the second split leg portion and positioned such that the second coil portion is wound in the first direction around at least the second connection portion; a third separator configured to increase magnetic resistance and provided in the second connection portion, and a fourth separator configured to increase magnetic resistance and provided in the fourth connection portion.

Description

TECHNICAL FIELD The present disclosure relates to a magnetically coupled reactor and a boosting circuit. Priority is claimed on Japanese Patent Application No. 2021-114397, filed on Jul. 9, 2021, the content of which is incorporated herein by reference. BACKGROUND ART Patent Document 1 describes a magnetically coupled reactor that is mounted on vehicles such as a hybrid vehicle, an electric vehicle, and the like. A reactor core of this reactor has two U-shaped split cores, and end surfaces of these split cores are butted together to form a closed magnetic circuit. Further, in Patent Document 1, multi-phase coils are wound around one reactor core to cancel out the DC magnetic flux by reversing the directions of the magnetic flux from each other. CITATION LIST Patent Document [Patent Document 1]Japanese Unexamined Patent Application, First Publication No. 2020-202633 SUMMARY OF INVENTION Technical Problem In the magnetically coupled reactor described in Patent Document 1, magnetic flux leaks from a portion where end surfaces of the reactor core are butted together. There is a possibility that, when this leakage magnetic flux interlinks with winding wires of the coil, eddy currents may be generated in the winding wires. The generation of such eddy currents causes a deviation in current density of the winding wires, which may cause a temperature rise. Therefore, there is a problem that requires measures such as increasing the size of the magnetically coupled reactor. The present disclosure has been made in view of such problems, and an object of the present disclosure is to provide a magnetically coupled reactor and a boosting circuit capable of reducing the interlinking of leakage magnetic flux with winding wires while suppressing an increase in size. Solution to Problem A magnetically coupled reactor according to an aspect of the present disclosure includes a reactor core forming a closed magnetic circuit, a first coil portion wound around the reactor core in a split manner, and a second coil portion wound in a split manner at a position apart from the first coil portion in a first direction in the reactor core. The reactor core includes a first outer core portion including two first leg portions extending in the first direction and a first base portion linking the two first leg portions on a first side in the first direction, a second outer core portion including two second leg portions extending in the first direction and a second base portion linking the two second leg portions on a second side in the first direction, and two intermediate core portions arranged side by side in a second direction intersecting the first direction and extending continuously and integrally in the first direction to connect the first leg portions and the second leg portions. The first coil portion and the second coil portion are wound in a split manner to span at least across the two intermediate core portions arranged side by side in the second direction, a first connection portion, to which the first leg portions and the intermediate core portion are connected, is positioned in an area in which the first coil portion is wound in the first direction, and a second connection portion, to which the second leg portions and the intermediate core portion are connected, is positioned in an area in which the second coil portion is wound in the first direction. Advantageous Effects of Invention According to the above aspect, it is possible to reduce the interlinking of leakage magnetic flux with winding wires while suppressing an increase in size. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a circuit diagram of a boosting circuit according to an embodiment of the present disclosure. FIG. 2 is a perspective view of a reactor according to an embodiment of the present disclosure. FIG. 3 is a plan view of a reactor core according to an embodiment of the present disclosure. FIG. 4 is a side view of the reactor as viewed from a second direction. FIG. 5 is a plan view corresponding to FIG. 3 of a reactor core according to a modification example of the embodiment of the present disclosure. DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of the present disclosure will be described in detail with reference to FIGS. 1 to 4. <Boosting Circuit> As shown in FIG. 1, a magnetically coupled reactor 10 of the present embodiment is a magnetically coupled reactor used in an interleaved boosting circuit 100. The boosting circuit 100 of the present embodiment is built in, for example, an inverter that drives an electric motor mounted on a hybrid hydraulic excavator or the like and boosts a terminal voltage V1 of a capacitor or the like to a voltage V2 required by the inverter. The boosting circuit 100 includes a smoothing capacitor 11A provided between input terminals Ti1 and Ti2, a smoothing capacitor 11B provided between output terminals To1 and To2, and a multi-phase (two-phase in the present embodiment) boosting chopper circuit 14. Each of these two-p