Maxell, Ltd.

Renesas Electronics Corporation

Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Hitachi Maxell, Limited

Hitachi Consumer Electronics Co., Ltd.

Katsuei Ichikawa

Osamu Kawamae

Kisho Ashida

Yasuo Yahagi

Yoshikazu Sugiyama

Kentarou Miyajima

Atsuo Soma

Keisuke Iwaishi

Yuuya Urushihata

Makoto Ishii

Motohiro Sasaki

Hitoshi Akiyama

Yasuaki Norimatsu

Takatoshi Shirosugi

Taku Takaki

A wireless power receiving device (WPRD) comprises an RFID responder and a beacon signal oscillator to transmit an RFID response in a case where there is no electric power which is necessary for transmission of a beacon signal. A wireless power transmitting device (WPTD) operates in a wide area power transmission mode for transmitting the electric power at a wide angle toward a direction that it receives the RFID response. When the WPRD receives the electric power in a wide area power transmission mode and transmission of the beacon signal becomes possible, it transmits the beacon signal. The WPTD operates in a centralized power transmission mode for transmitting the electric power at a narrower angle toward a direction receiving the beacon signal. Also, during the centralized power transmission mode, it cyclically performs transmission and reception of the beacon signal to detect positions of the WPRD and the WPTD.

Wireless power receiving device, wireless power transmitting device, wireless earphone, LED device, and wireless power transmitting and receiving system

The present invention suppresses leakage magnetic field. A power transfer coil configured to transmit or receive power includes: an inner coil; a first outer coil formed so as to surround the inner coil such that a magnetic flux opposite in phase to a magnetic flux outside the inner coil is generated outside the first outer coil, the first outer coil having one end connected to a first terminal and the other end connected to one end of the inner coil; and a second outer coil formed so as to surround the inner coil such that a magnetic flux opposite in phase to the magnetic flux outside the inner coil is generated outside the second outer coil, the second outer coil having one end connected to a second terminal and the other end connected to the other end of the inner coil.

Wireless power transfer using inductive coupling

Power transfer coil

Provided is a power reception unit that receives electric power transmitted from a power transmission unit, in which variation in power transmission efficiency is prevented. The power reception unit includes: a plurality of power reception coils that are configured to receive electric power by magnetic coupling with a power transmission coil of the power transmission unit; and a load coil that is disposed close to the power reception coils, in which a plurality of series resonant circuits that resonate at a frequency equal to a power transmission frequency are constituted by each of the plurality of power reception coils and a resonance capacity, the plurality of series resonant circuits are connected in series in a loop shape, and the load coil extracts received electric power from the series resonant circuits.

Power reception unit, power transmission unit, and wireless power transfer device

A non-contact power supply system is provided employing an electric power transmitting device which can improve the transmission efficiency of electric power, suppressing the circuit scale. The electric power transmitting device is configured with a resonance circuit including a resonance capacity and a resonance coil acting as a transmitting antenna, and a first coil arranged magnetically coupled with the resonance coil. The electric power transmitting device transmits electric power in a non-contact manner using resonant coupling of the resonance circuit. When transmitting the electric power, the electric power transmitting device controls the first coil to connect or disconnect both ends thereof so as to bring a resonance frequency of the resonance circuit close to a frequency of an electric power transmission signal outputted as the electric power to be transmitted.

Electric power transmitting device, non-contact power supply system, and control method

Generation of magnetic field leakage is suppressed. A coil of a power transmission device is provided so as to face a metal plate having a slot and a slit connected to the slot and is formed so that its inner peripheral portion is located on an outer side than the slot. A first capacitive element is connected to one end of the coil and a second capacitive element is connected to the other end of the coil.

Power transmission device

Provided is a power conversion device by which an inverter MOS transistors included in an inverter can be prevented from short-circuiting. It has a DC/DC converter unit converting a voltage of DC power to be inputted, a transformation unit transforming the DC power converted by the DC/DC converter unit, an inverter unit converting the DC power transformed by the transformation unit to AC power, a control unit driving/controlling the inverter unit, a wireless power reception unit receiving power fed by wireless power feed to supply it to the control unit, a wireless power transmission unit transmitting power to the wireless power reception unit, and a power supply unit supplying power to the wireless power transmission unit.

Wireless power transmission/reception system, power conversion device including the same, and power conversion method

A contactless power receiving device includes a power receiving coil receiving power from a contactless power transfer device, a rectifier circuit rectifying the power to form a rectified output on a high potential side and a rectified output on a low potential side, a smoothing circuit receiving the rectified output on the high potential side and the rectified output on the low potential side, and a switching power supply converting a DC voltage from the smoothing circuit to a first voltage. The smoothing circuit includes a first inductor transmitting the rectified output on the high potential side, a second inductor transmitting the rectified output on the low potential side, and a smoothing capacitance element to which the rectified output on the high potential side and the rectified output on the low potential side are supplied, and the rectified output on the low potential side is connected to a ground potential.

Contactless power receiving device, contactless power transfer device, and contactless power transfer and receiving device

The present invention improves charging efficiency in a wireless power transfer device. A wireless power transfer device wirelessly transfers power by using inductive coupling to a charging target device placed in the vicinity of a charging pad. The wireless power transfer device includes an amplifier for performing power amplification, a series resonant circuit constituted by a resonant capacitor and a power transfer coil, and a foreign material detection unit for detecting a non-charging device, which is not a charging target, placed in the vicinity of the charging pad. The foreign material detection unit is constituted by a pick-up coil, bandpass filters, detector circuits and a control circuit. The foreign material detection unit detects an IC card which is the non-charging device by a signal component emitted through inductive coupling with the power transfer coil from the device placed in the vicinity of the charging pad when transferring power.

Wireless power transfer device

A wide charging area and communication area are ensured in a non-contact power supply system with wireless communication. The present invention includes a resonance coil, a wireless communication antenna coil, a power supply coil, and a sensitivity adjustment circuit coupled to the power supply coil. When electric power is supplied in a contactless manner, the power supply coil and the resonance coil are coupled electromagnetically and electric power supply from the resonance coil is performed by using a magnetic resonance method. When wireless communication is performed, the magnetic fluxes of the wireless communication antenna coil are coupled with those of the resonance coil and sensitivity is enhanced by the sensitivity adjustment circuit.

Non-contact charging device, and non-contact power supply system using same

The present power transmission device performs a power transmission process for transmitting power in a wireless manner through electromagnetic field resonance coupling using a resonance circuit. In a case where a resonance frequency of the resonance circuit set to be the same as a frequency of a power transmission signal which is output as transmission power is deviated during transmission of the power, the present power transmission device detects a direction in which the resonance frequency is deviated and controls the power transmission process on the basis of a detection result thereof. Consequently, it is possible to determine not only whether or not a foreign substance is present in a power transmission region but also determines whether or not the foreign substance influences wireless power transmission with high accuracy, and thus reliability of the wireless power transmission system can be improved.

Power transmission device, wireless power feeding system, and control method

A non-contact power transmission system comprises: a primary coil including a power supply coil and a magnetic resonance coil; and a secondary coil including a load coil, thereby transmitting an electric power from the power supply coil at a self-resonating frequency of the magnetic resonance coil, which is determined by a parasitic capacitance between wound wires of the coil and a self inductance of the coil, and taking out the electric power supplied, from the load coil of the secondary coil through magnetic coupling, with non-contact, wherein the electric power is transmitted, with non-contact, with applying magnetic coupling in coupling between the power supply coil and the magnetic resonance coil and coupling between the magnetic resonance coil and the load coil.

Non-contact power transmission system, receiving apparatus and transmitting apparatus

Non-contact charging device with wireless communication antenna coil for data transfer and electric power transmitting antenna coil for transfer of electric power, and non-contact power supply system using same

A non-contact power-feeding device comprises: a power transmitting unit that includes a first antenna coil, an oscillator and a driver that enables generation of an AC magnetic field via the first antenna coil based upon a signal provided by the oscillator; and a power receiving unit that includes a second antenna coil that is magnetically coupled with the first antenna coil, wherein the first antenna coil comprises: a flat-plane spiral resonance coil wound with a plurality of turns; and a flat-plane spiral power-feeding coil that is wound with a plurality of turns outward relative to the resonance coil so as to surround the resonance coil, and is magnetically coupled with the resonance coil.

Non-contact power feeding device used in torque sensor having a coil enclosed in peripheral side of a resonance coil and is magnetically coupled with the resonance coil

Growing community of inventors

Tokyo, Japan

Katsuei Ichikawa