Abstract: A power conversion device includes a step-down-type transformer and a bridge circuit that rectifies output voltage of the transformer and supplies the rectified output voltage to a load. The bridge circuit is connected to a secondary winding of the transformer and includes MOS-FETs connected in series and diodes connected in series. A gate of the MOS-FET is connected to one end of a primary winding of the transformer with a capacitor interposed therebetween and a gate of the MOS-FET is connected to the other end of the primary winding of the transformer with a capacitor interposed therebetween. With this, a power conversion device and a wireless power transmission system that can achieve space saving and reduce loss in a rectifying element are provided.

Abstract: An inspecting apparatus is for a noncontact power transfer system that transfers electric power from a transmitting unit to a receiving device in a noncontact manner. The inspecting apparatus includes a coupling capacitance varying unit configured to vary at least one of a first coupling capacitance formed between a transmitting-side passive electrode and a receiving-side passive electrode and a second coupling capacitance formed between a transmitting-side active electrode and a receiving-side active electrode when the receiving device is placed on the transmitting unit, and a control unit configured to monitor an alternating-current voltage generated between the receiving-side passive electrode and the receiving-side active electrode of the receiving device or a direct-current voltage obtained through conversion by a rectifying circuit.

Abstract: A wireless power receiver device includes a sheet-like electrode sheet section and a power receiver section. The electrode sheet section includes a power receiver side active electrode and a power receiver side passive electrode that are substantially coplanar and formed into sheet-like shapes; lead lines that are coplanar with both the electrodes, extended from the respective electrodes, and formed into sheet-like shapes; and an insulation sheet that covers both the electrodes and both the lead lines from both sides thereof. The power receiver section includes a step-down unit that steps down an alternating-current voltage induced between end portions of the lead lines; a power receiver module that rectifies and smoothes the alternating-current voltage that is stepped down by the step-down unit; and a connector for outputting an output voltage of the power receiver module.

Abstract: A power transmission-side measurement tool is installed in a power transmitting apparatus that applies an AC voltage stepped up by a step-up transformer to an active electrode and a passive electrode. The power transmission-side measurement tool includes a measurement active electrode that faces the active electrode and a measurement passive electrode that faces the passive electrode, and the measurement active electrode and measurement passive electrode are shorted together. Frequency characteristics of a serial resonance circuit formed by leakage inductance of the step-up transformer and capacitors are measured in a state where the power transmission-side measurement tool is placed on the power transmitting apparatus.

Abstract: A power transmission system includes a charging station and a power receiving device. The charging station has a pair of first electrodes, and a signal source that emits an alternating current signal; and a step-up transformer that applies a stepped-up voltage to the pair of first electrodes. The power receiving device has a pair of second electrodes opposite to and that capacitively couple with the first electrodes; a step-down transformer; a rectifying and smoothing circuit that rectifies and smoothes the stepped-down AC voltage; and a load circuit, The charging station further has a potential stabilizing electrode that capacitively couples with the electrode connected to a reference potential of the power receiving device and the potential stabilizing electrode is connected to a reference potential of the charging station via a charge controller.

Abstract: A capacitance (Cp) is a capacitance formed between a transmitting-device-side passive electrode and a receiving-device-side passive electrode. A capacitance (Ca) is a capacitance formed between a transmitting-device-side active electrode and a receiving-device-side active electrode. A bridge circuit formed by Z1 to Z4 is connected to a secondary side of a step-up transformer, where Z1 represents an impedance of a first element, Z2 represents an impedance of a second element, Z3 represents an impedance of a series circuit formed by the capacitance (Ca) and a load, and Z4 represents an impedance of the capacitance (Cp). By determining the impedances Z1 to Z4 such that this bridge circuit is balanced, a potential at a receiving-device-side reference potential point is made equal to a ground potential. This reduces variation in receiving-device-side reference potential, reduces noise, and stabilizes the operation of a load circuit on the receiving device side.

Abstract: An active electrode and a passive electrode are electrically field-coupled with an active electrode and a passive electrode provided in a power transmission device, respectively. Power in a high frequency voltage excited on the active electrode and the passive electrode is supplied to a mobile unit via a step-down transformer, a rectification smoothing circuit, and a DC-DC converter. A CPU turns off switches when wireless communication is carried out. The passive electrode functions as a booster antenna that is magnetically field-coupled with an antenna coil. A high frequency signal outputted from an RF circuit is transmitted via the antenna coil and the passive electrode, and a high frequency signal transmitted from the power transmission circuit is inputted, via the passive electrode and the antenna coil, to the RF circuit.

Abstract: A power conversion device includes a step-down-type transformer and a bridge circuit that rectifies output voltage of the transformer and supplies the rectified output voltage to a load. The bridge circuit is connected to a secondary winding of the transformer and includes MOS-FETs connected in series and diodes connected in series. A gate of the MOS-FET is connected to one end of a primary winding of the transformer with a capacitor interposed therebetween and a gate of the MOS-FET is connected to the other end of the primary winding of the transformer with a capacitor interposed therebetween. With this, a power conversion device and a wireless power transmission system that can achieve space saving and reduce loss in a rectifying element are provided.

Abstract: A power transmission-side measurement tool is installed in a power transmitting apparatus that applies an AC voltage stepped up by a step-up transformer to an active electrode and a passive electrode. The power transmission-side measurement tool includes a measurement active electrode that faces the active electrode and a measurement passive electrode that faces the passive electrode, and the measurement active electrode and measurement passive electrode are shorted together. Frequency characteristics of a serial resonance circuit formed by leakage inductance of the step-up transformer and capacitors are measured in a state where the power transmission-side measurement tool is placed on the power transmitting apparatus.

Abstract: An inspecting apparatus is for a noncontact power transfer system that transfers electric power from a transmitting unit to a receiving device in a noncontact manner. The inspecting apparatus includes a coupling capacitance varying unit configured to vary at least one of a first coupling capacitance formed between a transmitting-side passive electrode and a receiving-side passive electrode and a second coupling capacitance formed between a transmitting-side active electrode and a receiving-side active electrode when the receiving device is placed on the transmitting unit, and a control unit configured to monitor an alternating-current voltage generated between the receiving-side passive electrode and the receiving-side active electrode of the receiving device or a direct-current voltage obtained through conversion by a rectifying circuit.

Abstract: A power transmission system includes a charging station and a power receiving device. The charging station has a pair of first electrodes, and a signal source that emits an alternating current signal; and a step-up transformer that applies a stepped-up voltage to the pair of first electrodes. The power receiving device has a pair of second electrodes opposite to and that capacitively couple with the first electrodes; a step-down transformer; a rectifying and smoothing circuit that rectifies and smoothes the stepped-down AC voltage; and a load circuit, The charging station further has a potential stabilizing electrode that capacitively couples with the electrode connected to a reference potential of the power receiving device and the potential stabilizing electrode is connected to a reference potential of the charging station via a charge controller.

Abstract: An active electrode and a passive electrode are electrically field-coupled with an active electrode and a passive electrode provided in a power transmission device, respectively. Power in a high frequency voltage excited on the active electrode and the passive electrode is supplied to a mobile unit via a step-down transformer, a rectification smoothing circuit, and a DC-DC converter. A CPU turns off switches when wireless communication is carried out. The passive electrode functions as a booster antenna that is magnetically field-coupled with an antenna coil. A high frequency signal outputted from an RF circuit is transmitted via the antenna coil and the passive electrode, and a high frequency signal transmitted from the power transmission circuit is inputted, via the passive electrode and the antenna coil, to the RF circuit.

Abstract: A wireless power receiver device includes a sheet-like electrode sheet section and a power receiver section. The electrode sheet section includes a power receiver side active electrode and a power receiver side passive electrode that are substantially coplanar and formed into sheet-like shapes; lead lines that are coplanar with both the electrodes, extended from the respective electrodes, and formed into sheet-like shapes; and an insulation sheet that covers both the electrodes and both the lead lines from both sides thereof. The power receiver section includes a step-down unit that steps down an alternating-current voltage induced between end portions of the lead lines; a power receiver module that rectifies and smoothes the alternating-current voltage that is stepped down by the step-down unit; and a connector for outputting an output voltage of the power receiver module.

Abstract: In a wireless power transmission system that transmits power from a power transmitting device to a power receiving device by electric field coupling, the power receiving device includes a power receiving module having a circuit for rectifying and smoothing an AC voltage which is generated between the active electrode and the passive electrode, a secondary battery, and a heat conducting plate that transfers heat which is generated in the power receiving module in power transmission from the power transmitting device to the power transmitting device. The power transmitting device includes a power transmission module which converts an input DC voltage to an AC voltage and applies the AC voltage between the active electrode and the passive electrode and a heat conducting plate which makes contact with the heat conducting plate and receives heat from the power receiving device.

Abstract: A power transmission system and power transmitter device that suppress degradation of communication quality in data communication even when the data communication and power transmission are performed concurrently. One end portion of a first communication unit of a power transmitter device is connected to a first communication coupling electrode, and one end portion of a second communication unit of a power receiver device is connected to a second communication coupling electrode that forms capacitive coupling with the first communication coupling electrode. The other end portion of the first communication unit is connected to a reference potential electrode of the power transmitter device, and the other end portion of the second communication unit is connected to a reference potential electrode of the power receiver device.

Abstract: A power reception device includes power reception electrodes which establish electric field coupling with power transmission electrodes provided in a power transmission device; and a transformer and rectification circuit which supply electric power based on the electric field excited by the power reception electrodes to a load. The power reception electrodes and the transformer form a parallel resonant circuit. The power transmission device includes a transformer which generates AC voltage to be applied to the power transmission electrodes; and a table in which correspondences between a plurality of resonant frequencies and a plurality of rated powers are described. The power transmission device sweeps the frequency of a PWM signal and detects the resonant frequency of the parallel resonant circuit, identifies a rated power corresponding to the detected resonant frequency based on the table, and adjusts the duty ratio of the PWM signal to match the identified rated power.

Abstract: A power transmission system is provided which is able to perform stable data communication with high communication sensitivity even when data communication and power transmission are performed at the same time. At least a third coupling electrode pair of first to third coupling electrode pairs is a reference electrode pair connected to a reference potential, one end of a first communication portion is connected to a reference potential of a power transmitting apparatus, and one end of a second communication portion is connected to a reference potential of a power receiving apparatus. Another end of the first communication portion is connected to either one of a power transmitting apparatus-side first or second coupling electrode, and another end of the second communication portion is connected to either one of a power receiving apparatus-side first or second coupling electrode.

Abstract: A capacitance (Cp) is a capacitance formed between a transmitting-device-side passive electrode and a receiving-device-side passive electrode. A capacitance (Ca) is a capacitance formed between a transmitting-device-side active electrode and a receiving-device-side active electrode. A bridge circuit formed by Z1 to Z4 is connected to a secondary side of a step-up transformer, where Z1 represents an impedance of a first element, Z2 represents an impedance of a second element, Z3 represents an impedance of a series circuit formed by the capacitance (Ca) and a load, and Z4 represents an impedance of the capacitance (Cp). By determining the impedances Z1 to Z4 such that this bridge circuit is balanced, a potential at a receiving-device-side reference potential point is made equal to a ground potential. This reduces variation in receiving-device-side reference potential, reduces noise, and stabilizes the operation of a load circuit on the receiving device side.

Abstract: A power transmitting apparatus includes a power transmitting apparatus side passive electrode and a power transmitting apparatus side active electrode, and a power receiving apparatus includes a power receiving apparatus side active electrode and a power receiving apparatus side active electrode. The power transmitting apparatus side active electrode and the power transmitting apparatus side passive electrode are not parallel with each other in terms of a positional relationship, and the power receiving apparatus side active electrode and the power receiving apparatus side passive electrode are not parallel with each other in terms of a positional relationship. By mounting the power receiving apparatus on the power transmitting apparatus, the power transmitting apparatus side passive electrode and active electrode respectively face the power receiving apparatus side passive electrode and active electrode.

Abstract: To provide a power receiving device having high power-receiving efficiency, able to be fed with power in a short time, and having made lighter and thinner with a smaller number of parts, and a power transmission system for feeding power to the power receiving device with high efficiency, the power receiving device has a resistive film type touch panel which has a movable transparent electrode membrane and a fixed transparent electrode membrane and causes a control unit to perform control to selectively switch between a position detecting circuit which detects a contact position on the touch panel and a power receiving circuit which supplies power received by using a movable transparent electrode as a power receiving electrode in an electric field coupling system to a secondary battery, and the power transmission system includes a power transmitting device which has a power transmission electrode for transmitting power by the electric field coupling system by using the movable transparent electrode membrane as