A coil device includes a core and a plurality of coils arranged in the core. A distance of a second gap formed by portions of the core located inside at least one of the coils is larger than that of a first gap formed by other portions of the core located between the coils next to each other.

According to one or more embodiments, a current limiting device is provided. The current limiting device includes a transformer including: a primary winding configured to accept an input current, a core electromagnetically coupled to the primary winding, and a secondary winding electromagnetically coupled to the core. The secondary winding is configured to provide a current limiting energy source based on the input current where the current limiting energy source is limited to a predetermined maximum current based on at least one characteristic of the core.

According to one or more embodiments, a current limiting device is provided. The current limiting device includes a transformer including: a primary winding configured to accept an input current, a core electromagnetically coupled to the primary winding, and a secondary winding electromagnetically coupled to the core. The secondary winding is configured to provide a current limiting energy source based on the input current where the current limiting energy source is limited to a predetermined maximum current based on at least one characteristic of the core.

The embodiments relate to a directional coupler including, in each case, one connection for a first, a second, a third, and a fourth port. The coupler includes a first coupling network for providing the connection for the first port and a second coupling network for providing the connection for the second port. The first and second coupling networks are both connected to the connections for the third and fourth ports, wherein the second coupling network has a first inductance connected between the third port and an electrical reference potential, a first capacitance connected between the fourth port and the electrical reference potential, a second capacitance connected between the third port and the second port, and a second inductance connected between the fourth port and the second port.

A cross-coupled multi-phase inductor that includes a single core and pairs of adjacent windings wound on the single core. Each member of an adjacent pair includes a first sub-winding and a second sub-winding which extends from the first sub-winding and each member is cross-coupled with the other member of the pair such that the first and second sub-windings of each member of the adjacent pair are disposed diametrically opposite or substantially diametrically opposite each other on the single core. This results in reducing core losses and increasing power conversion efficiency of the cross coupled multi-phase inductor.

An electromagnetic induction power generator includes: a current transformer attached to a power transmission line; a rectifier circuit for rectifying an AC voltage output from the current transformer; and a regulator circuit for regulating a DC voltage output from the rectifier circuit. The current transformer has a magnetic core attached to the power transmission line serving as a primary winding and a secondary winding magnetically coupled to the power transmission line through the magnetic core. The magnetic core is configured to start to be magnetically saturated around the minimum value within the fluctuation range of a current flowing through the power transmission line.

Techniques are provided for segmented windings of a coupled inductor within a DC-DC voltage converter or regulator. In an example, a coupled inductor circuit can include a first winding comprising a conductive coil having a central axis, and a second winding configured to magnetically couple with the first winding. The second winding can have a plurality of individual segments. Each individual segment can form a fraction of one turn of the second winding. Each segment can include a first conductor, a ground conductor, and a first switch to selectively couple, and selectively isolate, the first conductor and the ground conductor.

The application provides an integrated inductor and a power module. The integrated inductor includes a magnetic core, comprising: two winding columns disposed in parallel, each provided with an air gap; a first cover plate disposed under the two winding columns; a second cover plate disposed above the two winding columns, and opposite to the first cover plate; and a common column connected between the first and second cover plates, and disposed on one or both sides of the two winding columns; and two windings are respectively wound on the two winding columns, wherein a line frequency current component of a current flowing through each of the two windings surrounds the winding columns in the same direction, a phase of high-frequency current component of the current flowing through each of the two windings differs by 180°, and a coupling coefficient between the two windings is less than 0.1.

A system is provided for transferring power between a stator and a rotor of an excitation system. The stator and the rotor may form part of a rotary transformer that includes a primary winding and a secondary winding, where power is transferred from the primary winding to the secondary winding or conversely from the secondary winding to the primary winding.

A coil device includes a core and a plurality of coils arranged in the core. A distance of a second gap formed by portions of the core located inside at least one of the coils is larger than that of a first gap formed by other portions of the core located between the coils next to each other.