Non-contact power transmission device drive method and non-contact power transmission device
First Claim
1. A method for driving a contactless power transmission device including a setting surface, which includes a power supplying area, and a primary side circuit, which is located in the power supplying area and formed by a primary coil and a capacitor, wherein when an electric instrument is set in the power supplying area, the contactless power transmission device excites the primary coil located in the power supplying area and produces electromagnetic induction at a secondary coil of a power receiving device arranged in the electric instrument to supply power to the electric instrument, the method comprising:
- exciting the primary coil selectively using a first resonance frequency, which is in the proximity of a frequency determined by the primary coil and the capacitor located in the primary side circuit, and a second resonance frequency, which is in the proximity of a frequency determined by an inductance component and a capacitance component of the electric instrument when the primary coil is opposed to the secondary coil,wherein the exciting the primary coil includes;
exciting the primary coil at the first resonance frequency to detect metal or the electric device and determine whether or not metal exists in the power supplying area based on a primary coil that flows to the primary coil,suspending excitation of the primary coil at the first resonance frequency and the second resonance frequency when determined that the metal exists in the power supplying area or that nothing exists in the power supplying area,exciting the primary coil at the second resonance frequency to detect the electric instrument when determined that an object other than the metal exists in the power supplying area and determine whether or not the object existing in the power supplying area is the electric instrument based on the primary current, andexciting the primary coil at the second resonance frequency and supplying power to the electric instrument when determined that the object is the electric instrument.
2 Assignments
0 Petitions
Accused Products
Abstract
A primary coil (L1) is excited by selectively using: a first resonance frequency (AL) near a frequency determined by the primary coil (L1) and a primary-side capacitor (C), said primary coil (L1) 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 (L1) faces a secondary coil (L2).
19 Citations
19 Claims
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1. A method for driving a contactless power transmission device including a setting surface, which includes a power supplying area, and a primary side circuit, which is located in the power supplying area and formed by a primary coil and a capacitor, wherein when an electric instrument is set in the power supplying area, the contactless power transmission device excites the primary coil located in the power supplying area and produces electromagnetic induction at a secondary coil of a power receiving device arranged in the electric instrument to supply power to the electric instrument, the method comprising:
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exciting the primary coil selectively using a first resonance frequency, which is in the proximity of a frequency determined by the primary coil and the capacitor located in the primary side circuit, and a second resonance frequency, which is in the proximity of a frequency determined by an inductance component and a capacitance component of the electric instrument when the primary coil is opposed to the secondary coil, wherein the exciting the primary coil includes; exciting the primary coil at the first resonance frequency to detect metal or the electric device and determine whether or not metal exists in the power supplying area based on a primary coil that flows to the primary coil, suspending excitation of the primary coil at the first resonance frequency and the second resonance frequency when determined that the metal exists in the power supplying area or that nothing exists in the power supplying area, exciting the primary coil at the second resonance frequency to detect the electric instrument when determined that an object other than the metal exists in the power supplying area and determine whether or not the object existing in the power supplying area is the electric instrument based on the primary current, and exciting the primary coil at the second resonance frequency and supplying power to the electric instrument when determined that the object is the electric instrument. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A contactless power transmission device including a setting surface, which includes a power supplying area, and a primary side circuit, which is located in the power supplying area and formed by a primary coil and a capacitor, wherein when an electric instrument is set in the power supplying area, the primary coil located in the power supplying area is excited to produce electromagnetic induction at a secondary coil of a power receiving device arranged in the electric instrument to supply power to the electric instrument, the contactless power transmission device comprising:
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a signal generation circuit that selectively generates a first drive signal and a second drive signal, wherein the first drive signal excites the primary coil at a first resonance frequency, which is in the proximity of a frequency determined by the primary coil and the capacitor located in the primary side circuit, and the second drive signal excites the primary coil at a second resonance frequency, which is in the proximity of a frequency determined by an inductance component and a capacitance component of the electric instrument when the primary coil is opposed to the secondary coil; an excitation circuit that excites the primary coil in accordance with one of the first drive signal and the second drive signal provided from the signal generation circuit; and a control circuit that generates an excitation control signal for switching the first drive signal and the second drive signal generated by the signal generation circuit, the contactless power transmission device further comprising; an existence detection circuit that determines, when exciting the primary coil as the first resonance frequency, whether or not metal or an object other than metal exists in the power supplying area based on a primary current that flows to the primary coil; and an electric instrument determination circuit that determines, when exciting the primary coil at the second resonance frequency, whether or not the electric instrument is set in the power supplying area based on the primary current that flows to the primary coil. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18, 19)
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Specification