Abstract: An electromagnetic device according to an example of the present disclosure includes an outer iron-core, at least three leg iron-cores disposed radially inward of the outer iron-core and adjacent to each other at a radial center, and at least three coils, each of the at least three coils wound around the corresponding one of the at least three leg iron-cores, wherein each of the at least three coils has corresponding one of tapered portions having a winding area decreasing from a position near the outer iron-core on the corresponding one of the at least three leg iron-cores toward the radial center.

Abstract: An electromagnetic device includes: an outer circumferential iron core; at least three iron core leg portions; and coils, wherein each of the iron core leg portions is disposed in such a way that one end portion of the coil is supported by the outer circumferential iron core in a cantilevered manner and magnetically bound to the outer circumferential iron core while the other end portion is magnetically bound to the other end portions of the other iron core leg portions, and includes a base including an opening for housing a portion of the coils and holding the outer circumferential iron core at a position of a predetermined height from the mounting surface and a supporting structure that is disposed in contact with the other end portions of the iron core leg portions and that supports the iron core leg portions at a predetermined height from the mounting surface.

Abstract: A multiphase transformer according to the present disclosure includes a peripheral iron core, at least six leg iron cores arranged on an inner surface of the peripheral iron core at established intervals in a circumferential direction, and coils each wound on each of the at least six leg iron cores. Each of the at least six leg iron cores is arranged such that one end in the direction of a winding axis of the coil is magnetically connected to the peripheral iron core, and the other end in the direction of the winding axis is magnetically connected to the other end of another leg iron core of the at least six leg iron cores. The at least six coils are assigned to individual phases of the multiphase transformer in twos or more.

Abstract: A multistage structure electromagnetic device that includes a plurality of electromagnetic components stacked in multiple stages is provided. Each of the electromagnetic components includes: an outer circumferential iron core; at least three leg iron cores disposed at intervals in a circumferential direction on an inner surface side of the outer circumferential iron core; and coils respectively wound around the at least three leg iron cores, wherein each of the at least three leg iron cores is disposed to be magnetically connected to the outer circumferential iron core at one end in a direction of a winding axis line of the coil, and the other end is disposed to be magnetically connected to the other end of another leg iron core; and the coils of the electromagnetic component in one stage and the coils of the electromagnetic component in another stage are respectively connected in series.

Abstract: An electromagnetic apparatus includes an outer peripheral iron core, at least three leg iron cores arranged at intervals in a circumferential direction on an inner face side of the outer peripheral iron core, and a coil wound around each leg iron core, wherein the at least three leg iron cores are arranged such that one end of each leg iron core in a direction of a winding axis of the coil is magnetically coupled with the outer peripheral iron core, and the other end of each leg iron core is magnetically coupled with the other ends of other leg iron cores, and the outer peripheral iron core includes a recess recessed toward the inner face side on an outer face side thereof in a section corresponding to space between adjacent two leg iron cores in the circumferential direction.

Abstract: In a digitally controlled power source, a setting value of an output voltage therefrom is set in advance in the vicinity of an upper limit within a tolerable range of fluctuation. Even if a voltage drop is caused by starting currents that flow upon initial rise of DC-DC converters in a subsequent stage, such setting makes it possible to confine values of the output voltage within the tolerable range of fluctuation because the setting value of the output voltage is set in advance at a relatively high value. Accordingly, the starting currents in the DC-DC converters can be increased without restriction so that rise time for the power source can be shortened.

Abstract: In a digitally controlled power source, a setting value of an output voltage therefrom is set in advance in the vicinity of an upper limit within a tolerable range of fluctuation. Even if a voltage drop is caused by starting currents that flow upon initial rise of DC-DC converters in a subsequent stage, such setting makes it possible to confine values of the output voltage within the tolerable range of fluctuation because the setting value of the output voltage is set in advance at a relatively high value. Accordingly, the starting currents in the DC-DC converters can be increased without restriction so that rise time for the power source can be shortened.