An apparatus comprises a first substrate and two coils supported by the first substrate and arranged next to each other, the coils configured to each generate a magnetic field which produces eddy currents in and a reflected magnetic field from a conductive target, the two coils arranged so their respectively generated magnetic fields substantially cancel each other in an area between the coils. One or more magnetic field sensing elements are positioned in the area between the coils and configured to detect the reflected magnetic field.

The present disclosure relates to a cable for a high voltage winding of an electromagnetic induction device. The cable includes a conductor having a width w, and a shield arranged around at least a portion of the conductor, wherein in any cross-section of the conductor the conductor has rounded corners with a radius r in the range w/5<rw/3. A high voltage electromagnetic induction device having a cable forming a high voltage winding is also disclosed.

A thin resonant induction wireless power transmission transfer coil assembly designed for low loss and ease of manufacturing includes one or more printed circuit boards having a first conductor pattern wound in a spiral on a first side and a second conductor pattern wound in a spiral on a second side thereof, where the second conductor pattern is aligned with the first conductor pattern whereby the second conductor pattern reinforces magnetic flux generated by the first conductor pattern. The first and second conductor patterns are placed relative to one another so as to provide flux transmission in a same direction. One or more of such printed circuit boards form a wireless power transmission coil assembly with a conductive winding layer, a ferrite flux diversion layer, contormal spacing layers, an eddy current shield layer and an assembly enclosure.

Systems and methods to reduce the amplitude of undesirable eddy currents in conducting structures, e.g., induced by the translation of an FRC into a confinement chamber, while leaving beneficial eddy currents unaffected. This is achieved by inducing opposing currents in the same conducting structures prior to plasma translation into the confinement chamber.

A magnetic sheet includes a first region and a second region disposed adjacent to each other on a same surface, wherein the first region includes first crack lines formed in a first direction, and the second region includes second crack lines formed in a second direction.

An apparatus comprises a first substrate and two coils supported by the first substrate and arranged next to each other, the coils configured to each generate a magnetic field which produces eddy currents in and a reflected magnetic field from a conductive target, the two coils arranged so their respectively generated magnetic fields substantially cancel each other in an area between the coils. One or more magnetic field sensing elements are positioned in the area between the coils and configured to detect the reflected magnetic field.

A first coil device includes a first coil portion that faces a second coil portion of a second coil device in a first direction and includes a conductive wire, and at least one nonmagnetic member that includes a protrusion protruding to an outside of the first coil portion in a second direction orthogonal to the first direction. The nonmagnetic member includes an eddy current interrupter that interrupts a part of an eddy current generated in the nonmagnetic member.

An aspect of the present disclosure is a power conversion device including: a primary-side transformer to which a primary AC voltage is input from a primary-side circuit; and a secondary-side transformer that outputs a secondary AC voltage lower than the primary AC voltage to a secondary-side circuit. The primary-side transformer includes a primary-side primary winding to which the primary AC voltage is input, and a primary-side secondary winding to which power is transmitted from the primary-side primary winding. The secondary-side transformer includes a secondary-side primary winding constituting a closed circuit together with the primary-side secondary winding, and a secondary-side secondary winding to which power is transmitted from the secondary-side primary winding and which outputs the secondary AC voltage. The primary-side circuit and the closed circuit are connected to a common potential.

An inductive coil capable of providing power to the battery is described. The inductive coil is formed of a length of a wire having a conductive core capable of carrying an electrical current. The conductive core is surrounded by an insulating layer that electrically isolates the conductive core. Portions of the length of wire include a magnetically permeable material that is plated on an exposed surface of the conductive core.

Aspects generally relate to adjusting, or lowering, the Q of an inductor. In one embodiment, an integrated circuit includes an inductor and a conductive closed ring inside a periphery of the inductor. In another embodiment, there can be a plurality of closed rings inside the periphery of the inductor. The conductive closed rings are magnetically coupled to the inductor to adjust the Q.