Panasonic Intellectual Property Management Co., Ltd.

Kenichi Irie

Satoshi Hyodo

Hiroshi Kohara

Masashi Kawada

A primary coil (L) is excited by selectively using: a first resonance frequency (AL) near a frequency determined by the primary coil (L) and a primary-side capacitor (C), said primary coil (L) being placed in a power-supply area (AR); and a second resonance frequency (BL) near a frequency determined by a secondary-side inductance component and a secondary-side capacitance component, said components existing when the primary coil (L) faces a secondary coil (L).

Non-contact power transmission device drive method and non-contact power transmission device

A metal detection device includes a metal detection coil arranged in a metal detection area, wherein the metal detection coil is excited, and an electromagnetic wave radiated from the metal detection coil detects whether metal exists in the metal detection area. An oscillation circuit generates a sinusoidal oscillating current having a single fundamental frequency and supplies the oscillating current to the metal detection coil to excite the coil. A harmonic level detection circuit detects a harmonic component of the fundamental frequency component of the oscillating current and generates a detection signal. A comparison circuit compares a signal level of the detection signal and a pre-set reference value. A processing circuit determines whether metal exists in the metal detection area based on a comparison result. When determining that metal exists in the metal detection area, the processing circuit drives a notification unit to issue a notification indicating detection of metal.

Metal detection device using harmonic level detection

A contactless power supplying device includes a plurality of unit controllers that control a plurality of groups of power supplying unit circuits, which respectively excite a plurality of groups of primary coils. A clock signal generation circuit provides the plurality of unit controllers with a common clock signal. The plurality of unit controllers generates synchronization signals to excite the plurality of groups of primary coils in accordance with a common clock signal and provides the synchronization signals respectively to a plurality of power supplying unit circuit. The synchronization signals are rectangular wave pulses having the same cycle, and the plurality of groups of primary coils are excited with the same frequency.

Method of exciting primary coils in contactless power supplying device and contactless power supplying device

A contactless power supplying device is provided. A primary coil and a basic power supplying unit circuit are arranged in a power supplying area. The primary coil supplies secondary power through electromagnetic induction to a secondary coil of a power receiving device in the power supplying area. The basic power supplying unit circuit excites the primary coil in the power supplying area. The basic power supplying unit circuit transmits an oscillation signal from the power supplying area to the power receiving device, receives a modulated wave signal from the power receiving device that detects a modulation wave that is in accordance with a magnetic flux change, and detects the modulated wave signal to demodulate the modulation wave. A system control unit determines whether or not a metal foreign object is present in the power supplying area corresponding to the basic power supplying unit circuit based on the modulation wave.

Contactless power supplying device

A method for controlling a contactless power supplying device that excites a primary coil and supplies power using an electromagnetic induction effect to a secondary coil of a power receiving device arranged in an electric appliance is provided. A full-bridge circuit is full-bridge-operated to excite the primary coil when the electric appliance is on a setting surface. The full-bridge circuit is half-bridge-operated to excite the primary coil when the electric appliance is not on the setting surface.

Growing community of inventors

Osaka, Japan

Kenichi Irie