Abstract: A method for performing switching synchronization of a bridgeless rectifier in an electric vehicle (EV) wireless power transfer system may include receiving, by an EV control module, an input voltage of a transmission-side resonance circuit from a transmission-side of the EV wireless power transfer system; calculating, by the EV control module, a phase difference between the received input voltage and a voltage or a current selected in the bridgeless rectifier and a reception-side resonance circuit; and controlling, by an EV control module, switching time points of switches included in the bridgeless rectifier to decrease the calculated phase difference. The reception-side resonance circuit may be electromagnetically coupled to the transmission-side resonance circuit, and the bridgeless rectifier may be configured to rectify an output of the reception-side resonance circuit and to output the rectified output.

Abstract: A method for controlling wireless power transfer to an EV using a bridgeless rectifier may include detecting a phase difference between an input voltage of a transmission-side resonance circuit and an output voltage of a reception-side resonance circuit; after detecting the phase difference, predicting a resonance frequency change direction according to a preconfigured design condition; and controlling switching time points of switches included in the bridgeless rectifier in a direction compensating for the predicted change direction.

Abstract: A charging apparatus for an electric vehicle is provided. The apparatus includes an AC power input terminal receiving one AC input power from among single-phase AC power and multi-phase AC power. A power factor corrector having full bridge circuits receives the AC input power through the AC power input terminal. A link capacitor is charged through the power factor corrector. A first switch connects any one of an AC power input line and a neutral line of the AC power input terminal to the power factor corrector and a second switch selectively connects the AC power input terminal to the power factor corrector, or the link capacitor. The power factor corrector and the switch network operate based on a condition of received AC input power. The second switch includes a third switch and a fourth switch that connect each full bridge circuit to a positive battery electrode.

Abstract: A foreign object detection apparatus using a mobile laser in a wireless power transfer (WPT) system may comprise a laser transmitting part installed on one side of an upper portion of a transmission pad to generate a laser; a laser receiving part installed on an opposite side to the one side, and receiving the laser generated by the laser transmitting part; and a laser moving part for moving the laser transmitting part and the laser receiving part along the one side or the opposite side of the transmission pad.

Abstract: A wireless power reception apparatus including a bridgeless rectifier in a wireless power transfer (WPT) system for an electric vehicle (EV) may include: a bridgeless rectifier configured to rectify power transferred from a reception coil and to supply a direct current to a battery mounted in the EV; and a controller configured to control operation of the bridgeless rectifier. The bridgeless rectifier may include at least one switch and at least one diode connected to the at least one switch.

Abstract: A primary coil circuit of a ground assembly for wirelessly transferring power to a secondary coil includes: a primary coil magnetically coupled to the secondary coil and having a first terminal and a second terminal; a second capacitor having a first terminal and a second terminal connected to the first terminal of the primary coil; a first inductor having a first terminal coupled to a first input terminal of a power source and a second terminal coupled to the first terminal of the second capacitor; and a first capacitor having a first terminal coupled commonly to the second terminal of the first inductor and the first terminal of the second capacitor and a second terminal coupled commonly to the second terminal of the primary coil and a second input terminal of the power source.

Abstract: Disclosed are DC-to-AC converter control methods, ground assemblies and wireless power transfer methods using the same. A method for controlling a DC-to-AC converter of a ground assembly used for wireless power transfer, which includes first, second, third, and fourth switches arranged in a form of a bridge circuit between a power source and a primary coil, may comprise detecting a current flowing through the primary coil at a rising edge of an output voltage signal of the DC-to-AC converter; determining whether a strength of the current is at a negative level which falls within a predetermined reference range; and in response to a determination that the current is not at the negative level, changing switching frequencies of the DC-to-AC converter.

Abstract: A system and a method of controlling charge of a vehicle battery are provided. In particular, when a voltage of the vehicle battery is different from an output voltage of a commercially available quick charger, a compatibility problem is solved through a converter, thereby allowing an inverter, an electric motor, and a connector to have an increased efficiency and to maximize a reduction in size, weight, and material cost thereof.

Abstract: An electric vehicle includes: a battery configured to be charged with a first voltage; and a converter configured to boost, when power of a second voltage that is lower than the first voltage is received, the power of the second voltage to the first voltage, and to transfer the first voltage to the battery, so that the battery is charged with power of the first voltage, wherein when the power of the first voltage is received, the power of the first voltage is transferred to the battery to charge the battery.

Abstract: A wireless charging pad for transferring wireless power to an electric vehicle (EV) may comprise a plate type ferrite; and a coil disposed on an upper part of the plate type ferrite, the plate type ferrite may comprise a first ferrite member occupying an inside of a region defined by an inner surface of the coil and a second ferrite member occupying an outside of a region defined by an outer surface of the coil, and the second ferrite member has a wall shape surrounding the outer surface of the coil. Accordingly, safety can be improved by using the ferrite structure having excellent EMI characteristics in the wireless recharging pad, and the WPT efficiency can also be enhanced by using the ferrite structure having excellent electromagnetic characteristics in the wireless charging pad.

Abstract: A vibration device for generating vibration using sound pressure includes a cone paper damper generating vibration and a bobbin guiding a voice coil to allow the same to be stably provided. A connection member and a vibration probe are coupled at the center of the upper surface of the cone paper damper and the bobbin. The vibration device directly receives the vibration, which is generated from the cone paper damper, and transmits the vibration to the vibration probe. In addition, a human-body stimulation apparatus includes the vibration device having a cone paper damper for generating vibration and a bobbin for guiding a voice coil to allow the voice coil to be stably provided. The human-body stimulation apparatus receives a sound source using various forms of interfaces for storing or providing the sound source.

Abstract: The present disclosure provides a vehicle, a vehicle charging apparatus, vehicle charging system, and a vehicle charging method. The vehicle charging apparatus may include: a first coil; a second coil having one end selectively connected to one end of the first coil, and the other end selectively connected to the other end of the first coil; a third coil having one end selectively connected to one end of the first coil, and the other end selectively connected to the other end of the second coil; and a fourth coil having one end selectively connected to one end of the second coil, and the other end selectively connected to the other end of the first coil, where the fourth coil intersects the third coil.

Abstract: A single direct current (DC)-DC converter may include a switching part switching an input DC voltage; first and second transforming parts transforming an output of the switching part; a rectifying part rectifying outputs of each of the first and second transforming parts; and an output part filtering and outputting an output of the rectifying part.

Abstract: An active rectifier for a wireless power transfer system includes: a first rectifying circuit; a second rectifying circuit; a first switching circuit and a second switching circuit. The first rectifying circuit, the second rectifying circuit, the first switching circuit, and the second switching circuit are arranged in a form of a bridge circuit between a secondary coil of a vehicle and a battery of the vehicle, and the active rectifier controls the first and second switching circuits according to a charging status of the battery or an output status of the wireless power transfer system in order to change or maintain a charging power to the battery.

Abstract: A wireless charging method performed by a wireless power receiving apparatus for a vehicle includes: producing a resonance between a primary pad located outside of the vehicle and a secondary pad installed in the vehicle based on an initial switching frequency; and tuning a switching frequency of a direct current (DC) to DC (DC-to-DC) converter within a range determined based on the initial switching frequency, according to an output voltage outputted based on a resonance of the secondary pad which is caused by the primary pad.

Abstract: A method for detecting a foreign object between a transmission pad and a reception pad for wireless power transfer (WPT) may comprise steps of performing a zero phase angle (ZPA) control for a power transfer converter included in or connected to the transmission pad; detecting a characteristic parameter with respect to at least one of an input current and a switching frequency of the power transfer converter; and determining whether or not a foreign object exists between the transmission pad and the reception pad according to whether the characteristic parameter with respect to at least one of the input current and the switching frequency deviates from an allowable range.

Abstract: An active rectifier for a wireless power transfer system includes: a first rectifying circuit; a second rectifying circuit; a first switching circuit and a second switching circuit. The first rectifying circuit, the second rectifying circuit, the first switching circuit, and the second switching circuit are arranged in a form of a bridge circuit between a secondary coil of a vehicle and a battery of the vehicle, and the active rectifier controls the first and second switching circuits according to a charging status of the battery or an output status of the wireless power transfer system in order to change or maintain a charging power to the battery.

Abstract: A method for detecting a foreign object between a transmission pad and a reception pad for wireless power transfer (WPT) may comprise: performing, by a processor, a zero phase angle (ZPA) control for a power transfer converter included in or connected to the transmission pad; detecting, by the processor, a phase difference between an input current and an input voltage of the power transfer converter; and determining, by the processor, whether or not the foreign object exists between the transmission pad and the reception pad by comparing the phase difference with a reference value.

Abstract: An electric vehicle includes: a battery configured to be charged with a first voltage; and a converter configured to boost, when power of a second voltage that is lower than the first voltage is received, the power of the second voltage to the first voltage, and to transfer the first voltage to the battery, so that the battery is charged with power of the first voltage, wherein when the power of the first voltage is received, the power of the first voltage is transferred to the battery to charge the battery.

Abstract: A method for selectively performing a full bridge control and a half bridge control in a WPT system using an LCCL-S resonant network may include: performing the full bridge control by controlling the switches not connected in series of the full bridge inverter to operate simultaneously; calculating a coupling coefficient of the WPT system; determining whether it is possible to switch the full bridge control to the half bridge control based on the calculated coupling coefficient; in response to determining that it is possible to switch the full bridge control to the half bridge control, calculating a load of the WPT system; and performing the half bridge control for the full bridge inverter based on the calculated load.