Abstract: Provided is a wireless power resonator. The wireless power resonator may include a transmission line and a capacitor, may form a loop structure, and may further include a matcher to determine an impedance of the wireless power resonator.

Abstract: Provided are a transmission system and a wireless power transmission and reception controlling method. According to an embodiment, a wireless power receiver may include: a target communication unit configured to receive, from a wireless power transmitter, a wake-up request signal and synchronization information with respect to wireless power transmission, and to transmit a response signal with respect to the wake-up request signal to the wireless power transmitter; a load path switch configured to activate based on timing information included in the synchronization information; and a target resonator configured to receive wireless power from a source resonator of the wireless power transmitter, when the load path switch is activated.

Abstract: A source resonator for wirelessly transmitting power to a target device may include a magnetic field distribution adjusting unit that is configured to adjust the magnetic field generated by the source resonator. In one or more embodiments, the magnetic field distribution adjusting unit may adjust the magnetic field to be substantially uniform in a predetermined vicinity of the source resonator. For example, the magnetic field distribution adjusting unit may adjust the intensity of the magnetic field near the center of the source resonator to be substantially the same as the intensity of the magnetic field near an edge area of the source resonator.

Abstract: Provided is a wireless power resonator. The wireless power resonator, including a transmission line and a capacitor, may form a loop structure, and may additionally include a matcher to determine an impedance of the wireless power resonator.

Abstract: Provided are a direct current/direct current (DC/DC) converter and a wireless power receiver including the DC/DC converter. In one embodiment, a direct current-direct current (DC/DC) converter for use in a wireless power receiver, the DC/DC converter may include: a voltage converting unit configured to convert, DC voltage, to a predetermined DC voltage; a turn-on switch configured to control current flow of the DC voltage through the voltage converting unit; and a switching controller configured to: detect an amount of current of the voltage converting unit based on a first turn-on period of the turn-on switch, set a second turn-on period of the turn-on switch based on the detected amount of current, and control the turn-on switch based on the second turn-on period.

Abstract: A protector that protects a rectifier, and a wireless power receiver including the protector are provided. In one embodiment, a protector for an electronic device may include: a switch configured to control current flow to a rectifier of the electronic device; and a switch controller configured to: compare, with a predetermined threshold value, a voltage difference between an output voltage of the rectifier and a voltage of the electronic device; and transmit a control signal to the switch (i) to discontinue current flow to the rectifier when the voltage difference is greater than the predetermined threshold value, and (ii) to enable current flow to rectifier when the voltage difference is less than or equal to the predetermined threshold value.

Abstract: A high efficiency rectifier and a wireless power receiver including the rectifier are provided. In one embodiment, a rectifier may be formed of a full bridge diode circuit and may include: a first dual diode, a second dual diode, a third dual diode and a fourth dual diode forming the full bridge diode circuit, the full bridge diode circuit including: a first path configured to output voltage when the phase of an input voltage is positive, via the first dual diode and the fourth dual diode; and a second path configured to output voltage when the phase of the input voltage is negative, via the second dual diode and the third dual diode. In another embodiment, a rectifier may include: at least two full bridge diode circuits connected in parallel.

Abstract: A resonance power transmission system, and a method of controlling transmission and reception of a resonance power are provided. According to one embodiment, a method of controlling resonance power transmission in a resonance power transmitter may include: transmitting resonance power to a resonance power receiver, the resonance power having resonance frequencies which vary with respect to a plurality of time intervals; and receiving, from the resonance power receiver, information regarding the resonance frequency having the highest power transmission efficiency among the resonance frequencies used in the time intervals.

Abstract: Provided is a roof-type charging apparatus that charges multi-target device, while transmitting a resonance power. A roof-type charging apparatus using resonance power transmission includes a source resonance unit configured to transmit resonance power including a source resonator having a generally planar loop configuration and defining a space therein; a receiving unit configured to receive the resonance power transmitted from the source resonator; and a connecting unit configured to separate the source resonator and the receiving unit by a predetermined distance.

Abstract: A power converter which may be used in a resonance power transmission system and an apparatus for transmitting a resonance power are provided.

Abstract: A wireless power transmitter that transmits a resonance power via a multi-band resonator and a method thereof are provided. According to an aspect, a wireless power transmitter may include: a source unit configured to generate resonance power; a power amplifying unit configured to amplify the resonance power; and a multi-band resonance unit including at least two resonators, the at least two resonators configured to transmit the amplified resonance power to target resonators using different resonance bands.

Abstract: Provided is an apparatus that may control a direction of wireless power transmission. A radiative wireless power transmitter may include at least two first unit resonators to form a magnetic field with a target resonator based on an x-axis direction and a z-axis direction, and to transmit a resonance power to the target resonator, at least two second unit resonators to form a magnetic field with the target resonator based on the x-axis direction and a y-axis direction, and to transmit a resonance power to the target resonator, at least two third unit resonators to form a magnetic field with the target resonator based on the y-axis direction and the z-axis direction, and to transmit a resonance power to the target resonator, and a feeding unit to control resonance power transmission of the at least two first unit resonators, the at least two second unit resonators, and the at least two third unit resonators.

Abstract: A resonance power transmission system for controlling a supply voltage of a power converter based on power transmission efficiency is provided. According to an aspect, a resonance power transmitter configured to transmit resonance power to one or more resonance power receivers may include: a voltage controller configured to receive an input signal and to output voltage of a predetermined level; a source controller configured to control a signal level of the DC voltage based the number of resonance power receivers.

Abstract: A resonance power transfer system and a method for tracking resonant impedance in the resonance power transfer system are provided. An apparatus for tracking resonant impedance in a resonance power transfer system may include: a load sensor configured to detect the impedance of a load connected to a target device that receives resonance power; a target reflection signal detector configured to detect a reflection signal corresponding to the resonance power; a target impedance tracking unit configured to track the resonant impedance by adjusting a determination factor of a resonant frequency; and a target control unit configured to control the tracking of the resonant impedance based on whether there is a change of the impedance of the load, the reflection signal is detected, or both.

Abstract: An active rectifier and a wireless power receiver including the active rectifier are provided. According to an aspect, an active rectifier may include: a first loop configured to provide voltage when the phase of an input signal is positive; and a second loop configured to provide voltage when the phase of the input signal is negative, wherein the first loop and the second loop include a delay locked loop configured to compensate for reverse current leakage due to a delay of a switch included therein.

Abstract: Provided is an apparatus and method for adaptively adjusting an amount of a power to be wirelessly transmitted. In one embodiment, an adaptive resonance power transmitter may include: a source resonator configured to transmit resonance power to a resonance power receiver; a power amplifier configured to amplify a source power to a power level used by the resonance power receiver, the power amplifier comprising a matching network configured to match an impedance of the power amplifier to a predetermined impedance; and an adaptive matcher configured to adaptively match an impedance of the matching network with an impedance of the source resonator, based on the power level.

Abstract: A line structure is provided which includes a ferroelectric film which is formed on at least one surface of both sides of a substrate and a permittivity of which changes according to a magnitude of an applied voltage, an inductor which is formed on a first side of the substrate, and a capacitor which has a capacitance corresponding to the permittivity of the ferroelectric film and the substrate.

Abstract: Provided is a source-target structure matching controlling apparatus and method that may perform matching control of a source-target structure while resonance power is transmitted and received through the source-target structure. The source-target structure matching controlling apparatus may include a target resonator to receive, from a resonance power transmitter, the resonance power through a magnetic-coupling, and a rectifier to rectify the resonance power to generate a DC voltage, and provide the DC voltage to a load. The source-target structure matching controlling apparatus may detect an impedance of the load and a variance in the impedance, and may transmit, to the resonance power transmitter, information associated with the variance in the impedance of the load.

Abstract: Provided are a method and apparatus for controlling a resonance bandwidth in a wireless power transmission system. The apparatus may include a source resonator to transfer an electromagnetic energy to a target resonator, and a source resonance bandwidth setting unit to set a resonance bandwidth of the source resonator.

Abstract: A tunable capacitor using an electrowetting phenomenon includes a first electrode; a second electrode which is spaced apart from the first electrode and faces the first electrode; a fluidic channel which is disposed between the first electrode and the second electrode; a first insulating layer which is disposed between the first electrode and the fluidic channel; and a conductive fluid which is disposed in the fluidic channel and moves along the fluidic channel when a direct current (DC) potential difference occurs between the first and second electrodes. Accordingly, it is possible to fabricate the tunable capacitor with the simplified fabrication process, good reliability and durability, and no restriction on the tuning range.