An inductor includes a core including a multilayer part in which magnetic layers and insulating layers are alternately stacked; a coil including a wound part having a winding axis substantially perpendicular to a stacking direction of the multilayer part; and an element body. The multilayer part includes a first multilayer part in which first magnetic layers and insulating layers are alternately stacked and second and third multilayer parts in which second magnetic layers and insulating layers are alternately stacked, the electrical resistivity and/or relative magnetic permeability of the second magnetic layers being larger than those of the first magnetic layers. The first multilayer part has first and second surfaces that are perpendicular to the stacking direction and face each other and third and fourth surfaces that are parallel to the stacking and winding axis directions. The second and third multilayer parts are arranged on the first and second surfaces.

A current transformer includes a closed magnetic circuit and a secondary winding. A first part of the closed magnetic circuit completely surrounds a primary conductor, and a second part of the closed magnetic circuit forms the secondary winding. The second part of the closed magnetic circuit serves as a magnetic core of the secondary winding. The closed magnetic circuit forms a plurality of branch magnetic circuits at the second part, and a secondary winding is formed on each branch magnetic circuit. Each branch magnetic circuit serves as a magnetic core of a corresponding secondary winding. Each secondary winding is staggered with each other in at least one of the length, the height and the thickness.

A current transformer includes a closed magnetic circuit and a secondary winding. A first part of the closed magnetic circuit completely surrounds a primary conductor, and a second part of the closed magnetic circuit forms the secondary winding. The second part of the closed magnetic circuit serves as a magnetic core of the secondary winding. The closed magnetic circuit forms a plurality of branch magnetic circuits at the second part, and a secondary winding is formed on each branch magnetic circuit. Each branch magnetic circuit serves as a magnetic core of a corresponding secondary winding. Each secondary winding is staggered with each other in at least one of the length, the height and the thickness.

A multilayer coil component including a magnetic part formed of a ferrite material, a non-magnetic part formed of a non-magnetic ferrite material, and a coiled conductive part embedded in the magnetic part and the non-magnetic part. The non-magnetic part has an Fe content of 36.0 to 48.5 mol % in terms of Fe.sub.2O.sub.3, a Zn content of 46.0 to 57.5 mol % in terms of ZnO, a V content of 0.5 to 5.0 mol % in terms of V.sub.2O.sub.5, a Mn content of 0 to 7.5 mol % in terms of Mn.sub.2O.sub.3, and a Cu content of 0 to 5.0 mol % in terms of CuO with respect to the sum of the Fe content in terms of Fe.sub.2O.sub.3, the Zn content in terms of ZnO, the V content in terms of V.sub.2O.sub.5, and if present, the Cu content in terms of CuO, and the Mn content in terms of Mn.sub.2O.sub.3.

A multilayer coil component including a magnetic part formed of a ferrite material, a non-magnetic part formed of a non-magnetic ferrite material, and a coiled conductive part embedded in the magnetic part and the non-magnetic part. The non-magnetic part has an Fe content of 36.0 to 48.5 mol % in terms of Fe.sub.2O.sub.3, a Zn content of 46.0 to 57.5 mol % in terms of ZnO, a V content of 0.5 to 5.0 mol % in terms of V.sub.2O.sub.5, a Mn content of 0 to 7.5 mol % in terms of Mn.sub.2O.sub.3, and a Cu content of 0 to 5.0 mol % in terms of CuO with respect to the sum of the Fe content in terms of Fe.sub.2O.sub.3, the Zn content in terms of ZnO, the V content in terms of V.sub.2O.sub.5, and if present, the Cu content in terms of CuO, and the Mn content in terms of Mn.sub.2O.sub.3.

A multilayer coil component including: a magnetic part that contains Fe, Zn, V, and Ni and optionally contains Mn and/or Cu; and a conductor part that contains copper. In the magnetic part, Fe is in an amount of 34.0 to 48.5 mol % expressed as Fe.sub.2O.sub.3 equivalent, Zn is in an amount of 6.0 to 45.0 mol % expressed as ZnO equivalent, Mn is in an amount of 0 to 7.5 mol % expressed as Mn.sub.2O.sub.3 equivalent, Cu is in an amount of 0 to 5.0 mol % expressed as CuO equivalent, and V is in an amount of 0.5 to 5.0 mol % expressed as V.sub.2O.sub.5 equivalent, with respect to the total amount of Fe expressed as Fe.sub.2O.sub.3 equivalent, Zn expressed as ZnO equivalent, V expressed as V.sub.2O.sub.5 equivalent, and Ni expressed as NiO equivalent, and optionally present Cu expressed as CuO equivalent and optionally present Mn expressed as Mn.sub.2O.sub.3 equivalent.

A multilayer coil component including: a magnetic part that contains Fe, Zn, V, and Ni and optionally contains Mn and/or Cu; and a conductor part that contains copper. In the magnetic part, Fe is in an amount of 34.0 to 48.5 mol % expressed as Fe.sub.2O.sub.3 equivalent, Zn is in an amount of 6.0 to 45.0 mol % expressed as ZnO equivalent, Mn is in an amount of 0 to 7.5 mol % expressed as Mn.sub.2O.sub.3 equivalent, Cu is in an amount of 0 to 5.0 mol % expressed as CuO equivalent, and V is in an amount of 0.5 to 5.0 mol % expressed as V.sub.2O.sub.5 equivalent, with respect to the total amount of Fe expressed as Fe.sub.2O.sub.3 equivalent, Zn expressed as ZnO equivalent, V expressed as V.sub.2O.sub.5 equivalent, and Ni expressed as NiO equivalent, and optionally present Cu expressed as CuO equivalent and optionally present Mn expressed as Mn.sub.2O.sub.3 equivalent.

A control device for a power conversion device using a multi-phase magnetic coupling reactor is provided. The multi-phase magnetic coupling reactor including: a first outer coil; a second outer coil; an inner coil; and a core. Directions of magnetic fluxes generated in the first outer coil, the second outer coil, and the inner coil are opposite to each other in any combination. The control device is configured to switch among a one-phase operation, a two-phase operation, and a three-phase operation. The control device is configured to select two phases of the first outer coil and the second outer coil in the two-phase operation, and the control device is configured to select one of the first outer coil and the second outer coil in the one-phase operation before the two-phase operation or a one-phase operation after the two-phase operation.

This new type of transformer comprises a ferromagnetic drum-type core characterized in that the drum core has a plurality of holes or windows parallel to the drum longitudinal shaft to place the windings being the windows arranged close to the periphery of the drum symmetrically distributed at 360° of the circumference, each winding being parallel to the longitudinal shaft of the drum and each one of the windings crossing said longitudinal shaft. The core comprises two main components: a central body and an air gap filling system. The central body is formed by a plurality of silicon steel sheets, stacked one over the other, each of them has slots or spaces on its periphery thereof to place the windings and with an air gap filling system. Said filling system can be: wedge-shaped sheets, set of sheets extending parallel to the shaft of the core or a metal sheet wound around the central body.

This new type of transformer comprises a ferromagnetic drum-type core characterized in that the drum core has a plurality of holes or windows parallel to the drum longitudinal shaft to place the windings being the windows arranged close to the periphery of the drum symmetrically distributed at 360° of the circumference, each winding being parallel to the longitudinal shaft of the drum and each one of the windings crossing said longitudinal shaft. The core comprises two main components: a central body and an air gap filling system. The central body is formed by a plurality of silicon steel sheets, stacked one over the other, each of them has slots or spaces on its periphery thereof to place the windings and with an air gap filling system. Said filling system can be: wedge-shaped sheets, set of sheets extending parallel to the shaft of the core or a metal sheet wound around the central body.