Abstract: A power-receiving device includes a secondary-side coil which can receive a first alternating current power without contact from a power-sending device having a primary side coil into which first alternating current power is input. The power-receiving device comprises a first power transmission path, a second power transmission path, a common path positioned in common with the first and second power transmission paths, and a voltage regulator arranged on the common path. The voltage regulator rectifies the first alternating current power received by the secondary coil or the second alternating current power from a connecting portion, converts the rectified power to a predetermined specific voltage value, and outputs the power.

Abstract: A non-contact power transmission device equipped with a ground-side device and a vehicle-side device. The ground-side device has a primary-side coil to which alternating-current power is input. The vehicle-side device includes a secondary-side coil, a battery, a secondary-side matching device, and a charging device. The secondary-side coil receives alternating-current power from the primary-side coil in a non-contact manner. The secondary-side matching device is provided between the secondary-side coil and the battery, and has a predetermined fixed inductance and fixed capacitance. The charging device has a switching element that performs a switching operation with a prescribed cycle. The charging device adjusts the duty ratio of the switching operation in accordance with the impedance of a load.

Abstract: A contactless power transmission device includes a switching unit that switches a power transmission line so that a first power is transmitted through the first line when an AC power supply outputs a first AC power and so that a second power is transmitted through a second line when the AC power supply outputs a second AC power. An impedance conversion unit is arranged on the second line that converts an impedance from an output of the AC power supply to a variable load when the second power is transmitted through the second line to approach an impedance from the output of the AC power supply to the variable load when the first power is transmitted through the first line.

Abstract: A power receiving device receives alternating current power in a wireless manner from a power supply device including a primary coil that receives the alternating current power. The power receiving device includes a secondary coil, a variable load, a first impedance conversion unit, a second impedance conversion unit, a fixed load, and a switch. The switch switches an output destination, to which the alternating current power received by the secondary coil is output from the first impedance conversion unit, to the fixed load or to the second impedance conversion unit and the variable load.

Abstract: A power receiving device receives alternating current power in a wireless manner from a power supply device including an alternating current power supply and a primary coil. The power receiving device includes a secondary coil, a variable load, an impedance conversion unit, and an acknowledgement unit. Under a situation in which the acknowledgement unit acknowledges that the value of the alternating current power output from the alternating current power supply is unvaried, the impedance of the impedance conversion unit is variably controlled when an electrical property that is dependent on a relative position of the primary coil and the secondary coil varies.

Abstract: A power-receiving device includes a secondary coil, which wirelessly receives AC power from a power-supply device having a primary coil, a variable load, in which an impedance changes in accordance with the power value of the input power, a PFC circuit having a first switching element, and a DC/DC converter having a second switching element. The PFC circuit rectifies the AC power received by the secondary coil and improves the power factor by adjusting the duty cycle in switching operation of the first switching element in accordance with the impedance fluctuation of the variable load. The DC/DC converter is configured to convert the voltage of the DC power to a different voltage and output the converted voltage to the variable load, and to adjust the duty cycle in switching operation of the second switching element in accordance with the impedance fluctuation of the variable load.

Abstract: A power-receiving device includes a secondary-side coil which can receive a first alternating current power without contact from a power-sending device having a primary side coil into which first alternating current power is input. The power-receiving device comprises a first power transmission path, a second power transmission path, a common path positioned in common with the first and second power transmission paths, and a voltage regulator arranged on the common path. The voltage regulator rectifies the first alternating current power received by the secondary coil or the second alternating current power from a connecting portion, converts the rectified power to a predetermined specific voltage value, and outputs the power.

Abstract: A non-contact power transmission device equipped with a ground-side device and a vehicle-side device. The ground-side device has a primary-side coil to which alternating-current power is input. The vehicle-side device includes a secondary-side coil, a battery, a secondary-side matching device, and a charging device. The secondary-side coil receives alternating-current power from the primary-side coil in a non-contact manner. The secondary-side matching device is provided between the secondary-side coil and the battery, and has a predetermined fixed inductance and fixed capacitance. The charging device has a switching element that performs a switching operation with a prescribed cycle. The charging device adjusts the duty ratio of the switching operation in accordance with the impedance of a load.

Abstract: A contactless power transmission device includes a switching unit that switches a power transmission line so that a first power is transmitted through the first line when an AC power supply outputs a first AC power and so that a second power is transmitted through a second line when the AC power supply outputs a second AC power. An impedance conversion unit is arranged on the second line that converts an impedance from an output of the AC power supply to a variable load when the second power is transmitted through the second line to approach an impedance from the output of the AC power supply to the variable load when the first power is transmitted through the first line.

Abstract: A contactless power transmission device is provided with an AC power source, a primary coil, a secondary coil, an electric component and a power factor calculation unit. The primary coil is supplied with AC power from the AC power source. The secondary coil is allowed to receive AC power from the primary coil. The electric component is supplied with the AC power that is received by the secondary coil. The power factor calculation unit calculates at least either the power factor with respect to the load from the output of the AC power source to the electric component, or the power factor with respect to the load from the output of the secondary coil to the electric component.