A feed unit includes: a power transmission section configured to perform power transmission with use of a magnetic field or an electronic field; a power limiting section provided on a power supply line from an external power source to the power transmission section; and a control section provided on a side closer to the external power source than the power limiting section, and including a power transmission control section, the power transmission control section being configured to control the power transmission.

The invented power feeding system includes power transmitting and power receiving devices. The power transmitting device includes an AC power source, a first electromagnetic induction coil, a first resonant coil, and a first capacitor. The power receiving device includes an antenna unit including a second resonant coil, a second capacitor, and a second electromagnetic induction coil; a charging circuit unit including a rectifier circuit, a power storage device, a current detection circuit for detecting a current value supplied to the power storage device, and a voltage detection circuit for detecting a voltage value applied to the power storage device; and a communication control unit including a control circuit for generating a selection signal based on the detected current value and the detected current voltage, a plurality of switches to be turned on or off by the selection signal, and passive elements electrically connected to the plurality of switches.

A method for determining parameters of a wireless power transmission system is disclosed where the wireless power transmission system transmits power from a power transmission device to a power reception device via electric field coupling. The parameters include a coupling coefficient ke of an electric field coupling unit that is formed of active electrodes and passive electrodes of the power transmission device and the power reception device.

Power management and power transfer systems within the transmit and receive portions of an inductive charging system. An inductive charging system may include an inductive charging station to transmit power and a portable electronic device to receive power. Embodiments may take the form of power transfer systems within an inductive charging station including load-based transmit frequency adjustments. Embodiments may also take the form of power management systems within portable electronic devices which conserve power by disconnecting circuits from ground when those circuits are in an idle state.

A faulted circuit indicator includes a microprocessor or discrete logic to determine a fault condition and initiate one or more fault indications, a super capacitor, a battery, and power supply circuitry for providing power to the microprocessor and one or more fault indicators. The power supply circuitry: inductively receives energy from a power line; determines whether an induced voltage is sufficient to power one or more functions of the FCI device; and if not, determines whether available voltage from the super capacitor is sufficient to power the one or more functions of the FCI device. If so, the power supply circuitry draws voltage from the super capacitor and, if not, the power supply circuitry draws voltage from the battery when it is determined that the available voltage from the super capacitor is not sufficient to power the one or more functions of the FCI device.

A power receiving unit includes: a power receiving section configured to receive power that is fed from a power feeding unit in a non-contact manner; a rectification section configured to rectify the power received by the power receiving section; a method determination section configured to identify a feeding method of the power feeding unit; and a target voltage setting section configured to set a target voltage of the power rectified by the rectification section, to a value corresponding to the feeding method identified by the method determination section.

Configurations and methods of wireless power transmission using a laptop computer may include a transmitter and/or a receiver embedded in the laptop screen. The embedded transmitter may emit RF waves for the generation of pockets of energy that may be utilized by receivers in peripheral devices for charging or powering. Meanwhile, the receiver embedded in the laptop computer may collect RF waves from a separate transmitter for charging or powering the laptop computer.

A method for controlling communication between wireless power transmitter managers is disclosed. According to some aspects of this embodiment, wireless power transmission system may include one or more wireless power transmitter managers and one or more wireless power receivers for powering various customer devices. A WiFi connection may be established between wireless power transmitter managers to share information between system devices. Wireless power transmitter manager may need to fulfill two conditions to control power transfer over a customer device; customer device's signal strength threshold has to be significantly greater than 50%, such as 55% or more of the signal strength measured by all other wireless power transmitter managers and has to remain significantly greater than 50% for a minimum amount of time.

An electronic apparatus includes a switch control section configured to: determine whether a received signal is any one of a power signal and a data signal based on the received signal, and select any one of a power-reception operation and a data-transmission operation based on the determination of the received signal.

Systems, apparatus, and methods for controlling power modes in electronic devices are provided. A system may include an electronic device and an input device that sends power mode selection information via a network to a power mode selection receiving component in the electronic device. The electronic device includes a first power component that powers a first component, and a switching component that controls the first power component. The electronic device may include a second power component that powers a second component. The switching component may control the second power component. The power mode selection receiving component and the switching component may be powered independently of the first and the second component. If the power mode selection information indicates an off mode, the electronic device may provide power to the power mode selection receiving component and the switching component and not to the first and the second component.