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 planar transformer according to the present disclosure can include: at least one pair of cores arranged vertically and symmetrically; and a printed circuit board assembly including primary printed circuit boards having coil patterns forming a primary wiring and secondary printed circuit boards having coil patterns forming a secondary wiring, the secondary printed circuit boards respectively disposed over or under the primary printed circuit boards. The coil patterns of the primary printed circuit boards and the coil patterns of the secondary printed circuit boards can be alternately stacked.

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 low voltage DC-DC converter for a vehicle includes: a switching circuit including a plurality of capacitors and a plurality of switches and converting a high voltage output from a high voltage battery into an AC voltage; a transformer converting the AC voltage output from the switching circuit into a low voltage; a current sensor measuring a current value output from the transformer; and a controller comparing the current value measured by the current sensor with a reference value to determine whether a current mode is a continuous current mode or a discontinuous current mode, and controlling one of the plurality of switches to be turned on or off as the determination result.

Abstract: A low voltage DC-DC converter for a vehicle includes: a switching circuit including a plurality of capacitors and a plurality of switches and converting a high voltage output from a high voltage battery into an AC voltage; a transformer converting the AC voltage output from the switching circuit into a low voltage; a current sensor measuring a current value output from the transformer; and a controller comparing the current value measured by the current sensor with a reference value to determine whether a current mode is a continuous current mode or a discontinuous current mode, and controlling one of the plurality of switches to be turned on or off as the determination result.

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 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: A motor driving and battery charging apparatus is provided. The apparatus includes a motor having a plurality of coils, a rectifier circuit connected to the plurality of coils, and a high voltage battery. An inverter generates a driving current from an output voltage of the high voltage battery and supplies the driving current to the motor while the motor operates. While the high voltage battery is charged, the rectifier circuit rectifies an alternating current (AC) of an external power source, the motor and the inverter compensate for a power factor of the current rectified by the rectifier circuit, and the high voltage battery is charged with an output current of the motor and the inverter.

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: 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.

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 foreign object detection apparatus using reflected or refracted laser in a wireless power transfer (WPT) system may comprise a laser transmitter disposed on one side of an upper portion of a transmission pad to generate a laser; at least one laser guiding block disposed on one side or the other side of the upper portion of the transmission pad for receiving the laser generated by the laser transmitter and reflecting or refracting the received laser; and a laser receiver for sensing the laser through the at least one laser guiding block.

Abstract: Disclosed is a heat exchanger. The heat exchanger includes a plurality of plates superimposed on one another, and a plurality of heat transfer fins formed on the plurality of plates, and shaped into an airfoil, wherein a channel of a fluid between the superimposed plates is formed to perform a heat exchange.