Reactor, converter, and power conversion device
Provided is a reactor that can prevent a short circuit from occurring between turns of a coil even if a foreign object is present between turns. The reactor includes: an edgewise coil formed by a flat rectangular wire; a magnetic core; and a molded resin part that covers at least a portion of the magnetic core, wherein the edgewise coil includes a plurality of turns configured to form a rectangular shape, each of the plurality of turns includes four straight portions, and four curved corner portions that connect the adjacent straight portions to each other, each of the four corner portions includes an outer region in which a gap is provided between the adjacent turns, and the molded resin part is present in at least two of the gaps that are diagonally opposite to each other.
1 . A reactor comprising:
an edgewise coil formed by a flat rectangular wire;
a magnetic core including a middle core portion and two side core portions at opposite ends of the middle core portion; and
a molded resin portion that covers at least a portion of the magnetic core,
wherein the edgewise coil includes a plurality of turns configured to form a rectangular shape in which the middle core portion is disposed,
each of the plurality of turns includes four straight portions, and four curved corner portions that connect the adjacent straight portions to each other,
each of the four corner portions includes an outer region in which a gap is provided between the adjacent turns when viewed in a direction orthogonal to an axial direction of the turns of the edgewise coil,
the molded resin portion is present in at least two of the gaps that are diagonally opposite to each other,
in a cross-sectional view, a shortest distance between an outer circumferential surface of the middle core portion and the molded resin portion in the gaps of the corner portions is less than a shortest distance between the outer circumferential surface of the middle core portion and the molded resin portion at the straight portions such that displacement between the turns of the edgewise coil is suppressed, and
wherein each of the four corner portions has a bending radius of 10 mm or less.
2 . The reactor according to claim 1 ,
wherein each of the four corner portions further includes an inner region in which an interval between the adjacent turns is smaller than an interval between the gaps.
3 . The reactor according to claim 1 ,
wherein an aspect ratio a/b that is a ratio between a length a of a long side and a length b of a short side of the flat rectangular wire in a cross section thereof is 2 or more.
4 . The reactor according to claim 1 ,
wherein a maximum length between the adjacent outer regions is 10 μm or more and 1000 μm or less.
5 . The reactor according to claim 1 ,
wherein a length of a portion of the molded resin portion that is present in the gaps is 25% or more of a length of a long side of the flat rectangular wire in a cross section thereof.
6 . A converter comprising the reactor according to claim 1 .
7 . A power conversion device comprising the converter according to claim 6 .
8 . The reactor according to claim 1 ,
wherein each of the four corner portions further includes an inner region,
an interval between the adjacent turns in the inner region is zero, and
a maximum length between the adjacent outer regions is 10 μm or more and 1000 μm or less such that a length of a portion of the molded resin portion that is present in the gaps is 30% or more and 75% or less of a length of a long side of the flat rectangular wire in a cross section thereof.
9 . The reactor according to claim 1 ,
wherein along a width direction of the edgewise coil, a maximum length of a portion of the molded resin portion that is present between the adjacent outer regions of the corner portions is greater than a maximum length of a portion of the molded resin portion that is present between the adjacent outer regions of the straight portions.
10 . A reactor comprising:
an edgewise coil formed by a flat rectangular wire;
a magnetic core; and
a molded resin portion that covers at least a portion of the magnetic core,
wherein the edgewise coil includes a plurality of turns configured to form a rectangular shape,
each of the plurality of turns includes four straight portions, and four curved corner portions that connect the adjacent straight portions to each other,
each of the four corner portions includes an outer region in which a gap is provided between the adjacent turns,
a maximum length between the adjacent outer regions is 10 μm or more and 1000 μm or less such that a length of a portion of the molded resin portion that is present in the gaps is 30% or more and 75% or less of a length of a long side of the flat rectangular wire in a cross section thereof such that the molded resin portion is present in at least two of the gaps that are diagonally opposite to each other and displacement between the turns of the edgewise coil is suppressed, and
wherein each of the four corner portions has a bending radius of 10 mm or less.