A transmission antenna includes a resonance capacitor and a transmission coil coupled in series. A driver includes a bridge circuit that applies a driving voltage to the transmission antenna. A current sensor detects a current IS that flows through the bridge circuit. A foreign object detector detects the current IS that flows through the bridge circuit while changing the switching frequency applied to the bridge circuit. The foreign object detector judges the presence or absence of a foreign object based on the detection result.

The invented power feeding system includes power transmitting and power receiving devices. The power transmitting device includes an AC power source, a first electromagnetic induction coil, a first resonant coil, and a first capacitor. The power receiving device includes an antenna unit including a second resonant coil, a second capacitor, and a second electromagnetic induction coil; a charging circuit unit including a rectifier circuit, a power storage device, a current detection circuit for detecting a current value supplied to the power storage device, and a voltage detection circuit for detecting a voltage value applied to the power storage device; and a communication control unit including a control circuit for generating a selection signal based on the detected current value and the detected current voltage, a plurality of switches to be turned on or off by the selection signal, and passive elements electrically connected to the plurality of switches.

Disclosed are a wireless power transmitting apparatus and a wireless charging system. The wireless power transmitting apparatus includes: a detecting unit which detects transmitting current of a wireless power transmitting coil; and a charge monitoring unit which is able to determine that wireless charging has been completed when the detected transmitting current is shown to be below a charging threshold value over a set amount of time.

A method for transmitting data and a wireless charging equipment using the same are disclosed. When the wireless charger transmits data, an output current of the wireless charger is controlled at a preset current value so that there is a higher variation in amplitude of a current or a voltage on an inductive element to thereby enable a signal receiver to demodulate the signal. At the end of data transmission, the output current is resumed consistent with a driving current of the load at the moment. The present disclosure can address the problem of impossible normal communication in the wireless charger at the circumstance of a very low driving current of the load without any increase in cost and complexity of the circuit.

The present disclosure relates to a wireless power transmitter, a wireless power receiver and a wireless charging system in a wireless power transfer field. A wireless power transmitter disclosed herein includes a first coil configured to transfer a wireless power signal to a wireless power receiver, a second coil having a wire wound to transfer power to the wireless power receiver in a wireless manner, and a controller configured to control operations of the first and second coils, wherein the first coil is provided with a wire wound along an edge of a shape of the second coil.

The disclosure features resonators to wirelessly transfer energy to a wireless power device including a device resonator coil having a dimension D. The resonator can include a first plurality of conductor windings wound approximately in a first plane and having first and second conductor leads, and a second plurality of conductor windings wound in a second plane and having third and fourth conductor leads. The first and third conductor leads can be coupled to each other and the second and the fourth conductor leads can be coupled to at least one capacitor. The first plane and second plane can be spaced apart by separation S and substantially parallel. The separation S between the first plane and second plane can be approximately equal to or greater than the dimension D of the device resonator coil.

A multi-mode wireless power receiving device and method are disclosed. The multi-mode wireless power receiving device can comprise: an antenna module comprising an outer loop and an inner loop; a mode control unit for controlling an operation mode of the antenna module; a switch connecting the outer loop and the inner loop, and operated by the mode control unit; an outer loop module for supporting a magnetic resonance method and NFC communication by using the outer loop, according to the operation of the switch; and an inner loop module using the outer loop and the inner loop simultaneously so as to support a magnetic induction method according to the operation of the switch, thereby transmitting power.

An inductive power transmitter comprises a first primary inductor configured to inductively couple a first secondary inductor and configured to hold a first variable electrical potential. The transmitter also comprises a second primary inductor configured to inductively couple a second secondary inductor that is configured to hold a second variable electrical potential. The primary inductors are arranged in an overlapping fashion on a substrate forming a charging surface. The first primary inductor is connected to a first driver capable of providing the first variable electrical potential, and the second primary inductor is connected to a second driver capable of providing the second variable electrical potential in a first embodiment while a second possibility is that the first primary inductor is connected to a first driver capable of providing the first variable electrical potential, and the second primary inductor comprises capacitor and is not connected to a driver.

An inductive power transfer transmitter 200 comprising: a transmitting coil 7; a main flyback switch S1 in series with the transmitting coil 7; and an active snubber circuit 202 connected in parallel with the main flyback switch S1; wherein the main flyback switch S1 and the active snubber circuit 202 are configured to provide substantially zero voltage switching

A transmission antenna includes a closed-loop core having at least two electrically-conductive windings arranged on the closed-loop core. The windings are each electrically-actuated to generate a magnetic flux along the closed-loop core in opposing directions. The transmission antenna may generate a polarized magnetic field within a plane of the closed-loop core and provide broadband transmission of a polarized signal having a relatively flat frequency response. The transmission antenna is electrically-small, and the frequency of the polarized signal is nearly independent of the size of the closed-loop core. Multiple polarized signals may be provided, each being independently and continuously controlled through actuation of the windings. The direction of the polarized signal may also be varied. Additional windings for receiving a signal may simultaneously be employed on the closed-loop core. A method for transmitting a polarized signal with the transmission antenna is also provided.