Abstract:
A wireless power transmitting apparatus to wirelessly transmit power to a wireless power receiving apparatus, the wireless power transmitting apparatus including an AC power generating unit to generate quasi square-wave AC power having quasi square-wave voltage; and a transmission coil to transmit the quasi square-wave AC power to the wireless power receiving apparatus, wherein an input impedance of the wireless power transmitting apparatus has a maximum value at a fundamental frequency component, and wherein the input impedance of the wireless power transmitting apparatus has a minimum value at a second harmonic frequency component, and is increased as an order of a harmonic frequency component is increased from the second harmonic frequency component.
Abstract:
A method of supplying power in a wireless power receiver, can include receiving an AC power via a reception coil in the wireless power receiver; rectifying the AC power to a DC power; entering a charging mode by transferring the DC power to a load when a voltage of the DC power is equal to or greater than a first threshold voltage; maintaining the load in the charging mode when the voltage of the DC power is equal to or greater than a second threshold voltage in a state of the charging mode; and blocking the DC power to the load when the voltage of the DC power transitions from a voltage higher than the second threshold voltage to a lower voltage less than the second threshold voltage.
Abstract:
The present invention relates to a method for identifying a wireless power receiver, and apparatuses therefor. The method for identifying a wireless power receiver in a wireless power transmitter may comprise the steps of: detecting an object in a charging area; calculating the amount of impedance variation according to a change in transmission power when the object is detected; and determining, on the basis of the amount of impedance variation, whether or not the object is a normal receiver. Accordingly, the present invention has the advantage of being able to identify a normal receiver even in situations where the communication connection between the wireless power transmitter and the wireless power receiver is not normal.
Abstract:
An apparatus and method for wirelessly transmitting electromagnetic energy are provided. The apparatus includes a power source, a transmission unit, and a measurement unit. The power source supplies a power according to a certain frequency. The transmission unit receives the power to wirelessly transmit the received power through self resonance. The measurement unit measures a phase difference between a voltage and current of the transmission unit. The certain frequency is controlled according to the phase difference. Accordingly, the apparatus and method control only the frequency of the power supply when a resonance frequency is changed by the change of an ambient environment, thus enhancing energy transmission efficiency.
Abstract:
A wireless power transfer system according to an embodiment of the present invention is a wireless power transfer system having a receiving part for receiving power from a transmitting part, wherein the transmitting part comprises: a power conversion part comprising a full bridge inverter; and a control part for controlling the power conversion part using a pulse width modulation (PWM) control signal, the duty ratio of the PWM control signal being determined by a duty ratio in which the ratio of the magnitude of harmonics to the magnitude of a fundamental frequency among frequency components of the output signal of the power conversion part is a minimum.
Abstract:
A wireless power transmission device for wirelessly transmitting power to a wireless power reception device, according to one embodiment of the present invention, comprises: a first transmission coil for transmitting power to the wireless power reception device through a magnetic field; and a second transmission coil for transmitting power to the wireless power reception device through a magnetic field and arranged on the inner side of the first transmission coil, wherein the wireless power transmission device transmits power to the wireless power reception device through one coil between the first transmission coil and the second transmission coil on the basis of a coupling state between the wireless power transmission device and the wireless power reception device.
Abstract:
A wireless power transmission apparatus is described that comprises a mounting member, an upper transmission coil disposed on the mounting member, and first and second terminals disposed in the mounting member. The upper transmission coil comprises an outer coil part connected to the first terminal and formed in one-turn with respect to a central axis between the first and second terminals, a first inner coil part connected to the outer coil part and formed in a half-turn on a first side of the central axis, a second inner coil part connected to the first inner coil part, formed in a half-turn on a second side of the central axis, a third inner coil part connected to the second inner coil part, formed in a half-turn on the first side of the central axis, and a fourth inner coil part connected to the third inner coil part and the second terminal, formed in a half-turn on the second side of the central axis.
Abstract:
Disclosed is a wireless power transmitting apparatus to wirelessly transmit power to a wireless power receiving apparatus through a transmission resonance coil by using resonance. An AC power generating unit generates quasi square-wave AC power having quasi square-wave voltage. A transmission induction coil transmits the quasi square-wave AC power to the transmission resonance coil through electromagnetic induction.
Abstract:
A wireless power transmission apparatus can include a coil unit including a first layer including a first wireless power transmission coil having an asymmetric shape, and a second layer including a second wireless power transmission coil having an asymmetric shape, the first and second wireless power transmission coils being connected in parallel and partially overlapping with each other; and first and second terminals configured to simultaneously apply current to the first and second wireless power transmission coils connected in parallel, in which the first wireless power transmission coil and the second wireless power transmission coil have line symmetry with respect to an imaginary line extending between the first and second terminals and between the first and second layers.
Abstract:
A wireless power transmission method of a wireless power transmitter can include detecting a first wireless power receiver for charging through a first power transmission scheme; attempting to charge the first wireless power receiver when the first wireless power receiver is detected; proceeding to charge the first wireless power receiver to a first charging power; detecting a second wireless power receiver for charging through a second power transmission scheme when the first wireless power receiver is not detected or when charging the first wireless power receiver fails even after the wireless power transmitter attempted to charge the first wireless power receiver; attempting to charge the second wireless power receiver when the second wireless power receiver is detected; and proceeding to charge the second wireless power receiver to a second charging power.