The invention relates to a differential mode and common mode choke comprising: a ferromagnetic core comprising three branches (1, 2, 3) extending between a bottom part (5) and a top part (4), a first coil (b1) wound around the first lateral branch (1), a second coil (b3) wound around the second lateral branch (3), the first lateral branch (1) being separated from the top part (4) by a first air gap (e1) and from the bottom part (5) by a second air gap (e10), the second lateral branch (3) being separated from the top part (4) by a first air gap (e3) and from the bottom part (5) by a second air gap (e30), the central branch (2) being separated from the top part (4) by a first air gap (e2) and from the bottom part (5) by a second air gap (e20).

The invention relates to a differential mode and common mode choke comprising: a ferromagnetic core comprising three branches (1, 2, 3) extending between a bottom part (5) and a top part (4), a first coil (b1) wound around the first lateral branch (1), a second coil (b3) wound around the second lateral branch (3), the first lateral branch (1) being separated from the top part (4) by a first air gap (e1) and from the bottom part (5) by a second air gap (e10), the second lateral branch (3) being separated from the top part (4) by a first air gap (e3) and from the bottom part (5) by a second air gap (e30), the central branch (2) being separated from the top part (4) by a first air gap (e2) and from the bottom part (5) by a second air gap (e20).

A contactless power supply system includes a first power transmission coil, a plug power reception coil, a plug power transmission coil, and a first power reception coil. The first power transmission coil and the plug power reception coil are configured to satisfy a relational equation of (L.sub.2a/L.sub.1).sup.1/2=G1/K1=N.sub.2a/N.sub.1, where L.sub.1 represents a self-inductance of the first power transmission coil, L.sub.2a represents a self-inductance of the plug power reception coil, N.sub.1 represents a winding number of the first power transmission coil, N.sub.2a represents a winding number of the plug power reception coil, K1 represents a coupling coefficient of the first power transmission coil and the plug power reception coil, and G1 represents a voltage conversion gain of the voltage applied to the plug power transmission coil relative to the voltage applied to the first power transmission coil.

Provided is a first coil device that faces a second coil device in a facing direction, and wirelessly transmits or receives power, the first coil device including a first coil portion, and a first auxiliary magnetic member provided adjacent to the first coil portion in a first direction orthogonal to the facing direction. The first auxiliary magnetic member is configured to be closer to the second coil device with increasing distance in the first direction from the first coil portion.

Provided is a first coil device that faces a second coil device in a facing direction, and wirelessly transmits or receives power, the first coil device including a first coil portion, and a first auxiliary magnetic member provided adjacent to the first coil portion in a first direction orthogonal to the facing direction. The first auxiliary magnetic member is configured to be closer to the second coil device with increasing distance in the first direction from the first coil portion.

An inductor magnetic core and an inductor using the same are disclosed. The inductor magnetic core includes a middle column, an upper yoke, a lower yoke, and at least two high magnetically-permeable side columns. The middle column is disposed between a middle part of the upper yoke and a middle part of the lower yoke, a coil is wound the middle column, and a saturation magnetic flux density of the middle column is higher than that of the upper yoke and the lower yoke. The at least two high magnetically-permeable side columns are disposed in interval between the upper yoke and the lower yoke, and two ends of each high magnetically-permeable side column are connected to outer edges of the upper yoke and the lower yoke, respectively. The inductor magnetic core and the inductor of the present invention improves utilization of the yoke, and also provide compact structure and simple production.

This invention proposes a method of and a device for transmitting power via electromagnetic coupling from a transmission device to a set of reception devices, said method comprising a step of calculating by the transmission device, a first sum of given power levels defined by each reception device of said set of reception devices; if a maximum power that can be transmitted by the transmission device to said set of reception devices is less than said first sum, then performing a step of determining by said transmission device, based on said first sum and according to a set of criteria, a subset of reception devices among said set of reception devices, to which the transmission device transmits power.

A wireless energy transfer system may include a first layer of conductive material that may be positioned proximate to a second layer. The second layer of magnetic material may be positioned proximate to the first layer of conductive material and a third layer. The third layer may be positioned proximate to the second layer and a fourth layer, wherein the third layer may include a first resonator coil, wherein the first resonator coil may be configured to transfer wireless energy to a second resonator coil when the second resonator coil is proximate to the first resonator coil. The fourth layer may be positioned proximate to the third layer, wherein the fourth layer may include a plurality of conductive material.

Methods and systems for automatically aligning a power-transmitting inductor with a power-receiving inductor. One embodiment includes a method of applying a direct current pulse to a transmit coil of a power-transmitting inductor to attract the power-receiving inductor into alignment along an alignment axis.

An object of the present invention is to provide a small-sized and highly heat-dissipative reactor and a DC-DC converter using the reactor. A reactor according to the present invention includes a plate bus bar, a core, and a heat sink. The core includes a middle leg portion. The heat sink cools the plate bus bar. The plate bus bar is formed such that a winding axis of a winding including the plate bus bar passes through the middle leg portion. A main surface of the plate bus bar is disposed in parallel with a direction of the winding axis and thermally connected to the heat sink via an insulating layer.