A power transmitting unit is provided. The power transmitting unit includes a signal generator configured to generate a signal of a first frequency band for wireless charging, a power generation circuit configured to generate a modulation signal for modulating the signal of the first frequency band generated by the signal generator, and amplify a transmit power of the signal of the first frequency band based on voltage supplied from the outside of the power transmitting unit, a power transmission circuit configured to transmit the amplified transmit power to a power receiving unit via a first antenna, a second antenna configured to receive information about a charging state from the power receiving unit through a second frequency band, and a control circuit configured to control a duty and frequency of the modulation signal based on the charging state.

A power transmission device of this noncontact power supply apparatus has a transmission coil for supplying power to a power reception device, and a power supply circuit that supplies AC power to the transmission coil. A power reception device of the noncontact power supply apparatus has a reception coil for receiving power from the power transmission device, a variable capacity circuit that is connected to the reception coil in parallel and that can adjust capacitance, a resonance circuit that resonates with a frequency corresponding to the inductance of the reception coil and the capacitance of the variable capacity circuit, a voltage detection circuit that detects an output voltage from the resonance circuit, and a control circuit that controls the capacitance of the variable capacity circuit according to the output voltage.

In a system for non-contact transmission of electrical energy to a mobile part movably arranged on a facility floor, a charge unit is situated in a recess of the floor, the charge unit has a receiving part having upper and lower cover parts, a primary winding is accommodated in the upper cover part, the receiving part at least partially restricts a space region that accommodates an electronic circuit, a bore penetrates the lower cover part, and terminates via its first end region in the space region and terminates via its other end region in a further space region which is at least partially restricted by a dome wall provided on the lower cover part, and a diaphragm is situated on the bore.

In a system for a non-contact transmission of electrical energy to a mobile part, the system has a bore introduced into a floor material, a frame part is accommodated in the bore, a receiving part is situated in the frame part, an electronic circuit is situated in the receiving part, the receiving part is at least partially covered by a cover part in the manner of a housing, in particular on one of its sides, a sheet-metal part is situated between the receiving part and the frame part, and the sheet-metal part touches the receiving part and the sheet-metal part touches the frame part.

A wireless power transmitter includes: a power supply configured to supply a driving power; a first power transmitter including first bridge switching elements forming a first bridge circuit, and configured to receive the driving power to transmit a first power, wherein a magnitude of a first input voltage applied to the first bridge circuit is determined by a duty of at least one of the first bridge switching elements; a second power transmitter including second bridge switching elements forming a second bridge circuit, and configured to receive the driving power to transmit a second power, wherein a magnitude of a second input voltage applied to the second bridge circuit is determined by a duty of at least one of the second bridge switching elements; and a controller configured to output first and second power transmitting control signals respectively controlling the first bridge switching elements and the second bridge switching elements.

An RF energy harvesting system includes an antenna, an impedance matching network, an RF rectifier module, an enhanced RF rectifier module, a protection circuit, a power control module, an energy storage branch and load branches. The antenna receives RF signals and converts the RF signals into electric energy. The impedance matching network produces an initial voltage signal according to the electric energy output by the antenna. The RF rectifier module converts the initial voltage signal into a first voltage signal. The enhanced RF rectifier module converts the initial voltage signal into a second voltage signal. The power control module is self-driven through the first voltage signal and the second voltage signal. The RF rectifier module adjusts the internal electrical connection according to control signals of the power control module. The energy storage branch stores the electric energy output by the power control module.

The power transmission device includes a power transmission coil configured to transmit power in a wireless manner to a power reception coil of a power reception device, a plurality of foreign object detection coils disposed along an upper surface of the power transmission coil, and a power supply ECU.

An apparatus includes a power switch configured to conduct a dc or ac current, a sense switch having a first drain/source terminal and a gate connected to a first drain/source terminal and a gate of the power switch respectively, an amplifier having a first input coupled to a second drain/source terminal of the power switch and a second input coupled to a second drain/source terminal of the sense switch and a first current sense processing switch having a gate connected to an output of the amplifier.

A power transmission circuit is connected to a power transmission coil having a coil aperture. The power transmission circuit includes a conductive or magnetic power-transmission-coil near member opposed to the coil aperture of the power transmission coil, and a repeating coil arranged on a side opposite to a side on which the power-transmission-coil near member is arranged with respect to the power transmission coil and coupled to the power transmission coil at least via a magnetic field. When a shortest distance between the power transmission coil and the power-transmission-coil near member is expressed as (dt1) and a shortest distance between the power transmission coil and the repeating coil is expressed as (dt2), dt2dt1.

According to one embodiment, an electronic apparatus includes a signal detector and processor circuitry. The signal detector is configured to detect communication information based on a wireless signal. The processor circuitry is configured to determine at least one of (1) a first period to wait from a timing of when power transmission is ended to a timing of when power transmission is started, (2) a second period to wait from a timing of when the wireless signal is not detected to a timing of when power transmission is started, and (3) a third period for continuously performing power transmission. The processor circuitry is configured to transmit a power with electromagnetic wave according to at least one of the first period, the second period, and the third period.