Abstract: A wireless power transmitter includes: a converter including switching elements forming a bridge circuit, wherein the converter is configured to output an alternating current (AC) voltage including a frequency determined according to an operating frequency of at least one switching element among the switching elements; a resonator including an inductor and a capacitor, and configured to receive the AC voltage to wirelessly transmit power; and a controller configured to output control signals controlling the switching elements so that the converter performs a first mode operation in which an operating duty cycle is fixed and the operating frequency is varied, and an operation of the converter is switched from the first mode operation to a second mode operation in which the operating frequency is fixed and the operating duty cycle is varied, in response to the operating frequency reaching a first reference frequency.

Abstract: A thermoelectric composite material includes MXene inserted at a boundary of a crystal grain consisting of a thermoelectric material. Accordingly, the thermoelectric composite material may have a reduced thermal conductivity and an increased electrical conductivity. Furthermore, a mechanical property of the thermoelectric composite material may be improved. Thus, the thermoelectric composite material may improve a thermoelectric ability of a thermoelectric module.

Abstract: A wireless power transmission apparatus includes a resonator configured to be magnetically coupleable to a wireless power reception apparatus; an inverter configured to operate the resonator; and a resonant frequency controller configured to control a resonant frequency of the resonator in response to a change in operating frequency of the inverter.

Abstract: An apparatus for transmitting power wirelessly includes a power transmitter configured to transmit power wirelessly to an apparatus for receiving power wirelessly, and an identification information manager configured to transmit first identification information allocated to the apparatus for transmitting power wirelessly to other devices.

Abstract: A wireless power transmitter includes a common bridge circuit configured to apply a first alternating current (AC) voltage to a terminal of each of a first resonator and a second resonator of the resonators, a first sub-bridge circuit configured to apply a second alternating current (AC) voltage to another terminal of the first resonator while the first alternating current (AC) voltage is being applied to the terminal of the first resonator, and a second sub-bridge circuit configured to apply a third alternating current (AC) voltage to another terminal of the second resonator while the first alternating current (AC) voltage is being applied to the terminal of the first resonator.

Abstract: A wireless power transmitter includes a wireless power controller configured to receive an alternating current (AC) voltage, to convert the AC voltage into a direct current (DC) voltage, and to generate an induced current from the DC voltage according to a switching control for a transformer; and a resonator configured to be resonated by the induced current to wirelessly output charging power.

Abstract: A non-contact type power transfer apparatus includes a power converter configured to convert input power into transmission power; a power transmitter configured to transmit the transmission power in a non-contact manner; and a controller configured to provide a power conversion control signal to control a power conversion operation of the power converter according to a state of the transmission power, and to output an input power control signal to control a power level of the input power according to the power conversion control signal.

Abstract: A wireless power receiver included in a device, the wireless power receiver including a core part fixed to be adjacent to a surface of an internal part; a receiving coil wound around the core part; and a power circuit configured to provide power received from the receiving coil to the wearable device.

Abstract: A wireless power transmitter includes a sensor configured to sense an object, a power transmitter configured to wirelessly transmit power to a wireless power receiver, and a controller configured to determine whether the object is the wireless power receiver, and control the power transmitter to wirelessly transmit power to the wireless power receiver upon the object being determined to be the wireless power receiver, wherein the sensor and the power transmitter comprise separate coils.

Abstract: A non-contact power transmission device includes a power transmission unit configured to contactlessly provide electric power; a controller configured to provide location information of the non-contact power transmission device; and a communications unit configured to transmit the location information and product information received from a non-contact power reception device to a server, and receive an approval to transmit electric power to the non-contact power reception device from the server.

Abstract: A wireless power transmitter includes resonators electrically connected to each other and a resonance frequency varying unit configured to vary resonance frequencies of the resonators based on a change in an amount of power to be sent to a wireless power receiver from the wireless power transmitter.

Abstract: There are provided an apparatus for transmitting power wirelessly. The apparatus for transmitting power wirelessly may include a boosting unit boosting an input voltage, and an inverter unit inverting the boosted voltage output from the boosting unit to transmit power wirelessly. The inverter unit and the boosting unit are controlled by the same switching element.

Abstract: A wireless power transmitter for receiving external power from a power adaptor includes an output control signal generator configured to generate an output control signal from the external power, and supply the output control signal to the power adaptor; and a wireless power generator configured to generate power to be wirelessly transmitted to a wireless power receiver using the external power supplied by the power adaptor in response to the output control signal, and wirelessly transmit the generated power to the wireless power receiver.

Abstract: A wireless power transmitting method performed in a wireless power transmitting apparatus wirelessly transmitting power includes determining reception strength of a short-range wireless communication channel, adjusting an interval of a short beacon signal in response to a change in reception strength; and transmitting the short beacon signal at the interval.

Abstract: A wireless power transmitter includes: a converter including a first switch and a second switch, and configured to output alternating current (AC) power to an AC node between the first switch and the second switch; a common resonance capacitor connected to the AC node; and resonators connected to the common resonance capacitor, wherein each of the resonators includes a series capacitor, a resonance coil, and a sub-switch, connected to each other in series, and wherein the resonance coil is configured to transmit the power in a non-contact manner.

Abstract: A wireless power transmitting and receiving device includes: a coil including a first section having a first number of turns and configured to receive power and a second section having a second number of turns different from the first number of turns and configured to transmit power and a converting and rectifying unit configured to: rectify the power received through the coil, convert externally-supplied power into alternating current power, and apply the alternating current power to the coil.

Abstract: There are provided an apparatus apparatus for transmitting power wirelessly. The apparatus for transmitting power wirelessly may include a boosting unit boosting an input voltage, and an inverter unit inverting the boosted voltage output from the boosting unit to transmit power wirelessly. The inverter unit and the boosting unit are controlled by the same switching element.

Abstract: A wireless power transmitting and receiving device includes: a coil including a first section having a first number of turns and configured to receive power and a second section having a second number of turns different from the first number of turns and configured to transmit power and a converting and rectifying unit configured to: rectify the power received through the coil, convert externally-supplied power into alternating current power, and apply the alternating current power to the coil.

Abstract: A non-contact type power receiving apparatus, of which a voltage level of output power varies depending on a rated voltage of a battery, includes: a power receiving coil unit receiving a power in a non-contact scheme; a rectifying/multiplying unit rectifying the received power depending on controlling thereof and selectively multiplying a voltage level of the rectified power; and a controller selectively controlling a rectifying operation or a multiplying operation of the rectifying/multiplying unit to be performed depending on a selection signal.

Abstract: A wireless power transmitting and receiving device includes: a coil including a first section having a first number of turns and configured to receive power and a second section having a second number of turns different from the first number of turns and configured to transmit power and a converting and rectifying unit configured to: rectify the power received through the coil, convert externally-supplied power into alternating current power, and apply the alternating current power to the coil.