An inductor device includes a first inductor, a second inductor, and at least one switch circuit. The second inductor is arranged to enclose the first inductor, and use a topmost layer metal to resist external interference for the first inductor. The at least one switch circuit is coupled to the second inductor, and is arranged to receive at least one control voltage, wherein the at least one control voltage is arranged to adjust conduction degree of the at least one switch circuit.

A system includes a current transformer including: a primary coil, and a secondary coil including at least two taps; a tap selection circuit; a current measurement apparatus configured to produce an indication of an amount of current flowing in the secondary coil; a power supply electrically connected to a first one of the taps, the power supply configured to receive electrical power from the first one of the taps; and a controller coupled to the power supply and the current measurement apparatus, the controller configured to receive electrical power from the power supply and to control the tap selection circuit based on the indication of an amount of current in the secondary coil.

A system includes a current transformer including: a primary coil, and a secondary coil including at least two taps; a tap selection circuit; a current measurement apparatus configured to produce an indication of an amount of current flowing in the secondary coil; a power supply electrically connected to a first one of the taps, the power supply configured to receive electrical power from the first one of the taps; and a controller coupled to the power supply and the current measurement apparatus, the controller configured to receive electrical power from the power supply and to control the tap selection circuit based on the indication of an amount of current in the secondary coil.

An energy harvesting device (CTH) installed in an electrical distribution system (EDS) for powering ancillary electrical devices (AD) used in the distribution system. The device includes a first voltage regulator circuit (CC) configured to produce a voltage matched to a power curve of a current transformer (CT) to which the device is electrically coupled. The device also includes a second and separate voltage regulator circuit (SVR) which continuously operates to maximize the amount of electrical energy recovered from the current transformer.

Balun device and differential phase shifter are provided. The balun device includes a first primary coil, a first secondary coil, a second primary coil and a second secondary coil, the first primary coil having a first terminal receiving a first differential signal, and a second terminal outputting a first in-phase component, the first secondary coil having a first terminal outputting a first component orthogonal to the first in-phase component, and a second terminal coupled to AC ground, the second primary coil having a first terminal receiving a second differential signal, and a second terminal outputting a second in-phase component; the second secondary coil having a first terminal outputting a second component orthogonal to the second in-phase component, and a second terminal coupled to AC ground; phase differences between the first and second differential signals, between the first and second in-phase components, between the first and second orthogonal component are 180°.

Balun device and differential phase shifter are provided. The balun device includes a first primary coil, a first secondary coil, a second primary coil and a second secondary coil, the first primary coil having a first terminal receiving a first differential signal, and a second terminal outputting a first in-phase component, the first secondary coil having a first terminal outputting a first component orthogonal to the first in-phase component, and a second terminal coupled to AC ground, the second primary coil having a first terminal receiving a second differential signal, and a second terminal outputting a second in-phase component; the second secondary coil having a first terminal outputting a second component orthogonal to the second in-phase component, and a second terminal coupled to AC ground; phase differences between the first and second differential signals, between the first and second in-phase components, between the first and second orthogonal component are 180°.

A digital communication station includes a coupled inductor, driver circuitry, and a digital transceiver. The coupled inductor includes (1) a first winding connected between a first digital communication node and a first power node, (2) a second winding connected between a second digital communication node and a second power node, and (3) a third winding. The driver circuitry is configured to drive the third winding to increase respective inductance values of the first and second windings, and the digital transceiver is communicatively coupled to the first digital communication node and the second digital communication node.

Coil structures and methods of forming are provided. The coil structure includes a substrate. A plurality of coils is disposed over the substrate, each coil comprising a conductive element that forms a continuous spiral having a hexagonal shape in a plan view of the coil structure. The plurality of coils is arranged in a honeycomb pattern, and each conductive element is electrically connected to an external electrical circuit.

The present invention provides a magnetic-inductance component, and relates to the field of magnetic circuit theory and application, and in particular, to the design of magnetic circuit components. The magnetic-inductance component is a multi-turn short-circuit coil wound around a magnetic circuit. A magnetic-inductance value of the magnetic-inductance component is adjusted by selecting metal conductors with different numbers of turns, materials, cross-sectional areas, and lengths to change an amplitude and a phase of a magnetic flux of the magnetic circuit. The present invention purposely changes the operating state and operating trajectory of a vector in the magnetic circuit by adding the magnetic-inductance component to the magnetic circuit or removing the magnetic-inductance component from the magnetic circuit, to make a state of a magnetic flux vector in the magnetic circuit to be consistent with a target magnetic flux vector state. Compared with a magnetic circuit including a reluctance only, a magnetic circuit vector model built by using the magnetic-inductance component as a core is more consistent with the actual physical situation, which is beneficial to the improvement of the accuracy of magnetic circuit analysis and calculation.

The invention relates to a system for wirelessly charging an electrically chargeable device, in particular a mobile inspection robot, in a potentially explosive environment. The invention also relates to a charging station for use in such a system according to the invention. The invention further relates to an electrically chargeable device, in particular an inspection robot, for use in such a system according to the invention. In addition, the invention relates to a method for wirelessly charging an electrically chargeable device, in particular a mobile inspection robot, by using such a system according to the invention.