An HMD includes first and second batteries mounted therein, and includes a plurality of power receivers that receive power from the first and second batteries by wireless transmission, a power supply manager that monitors states of the first and second batteries, a communication interface that performs wireless communication with the first and second batteries, and a plurality of limiters that limit the power received by the plurality of power receivers. A controller causes the limiters to limit power, which is supplied to a load, according to a power use state of the load in the device, and the power supply manager acquires information of remaining power storage amounts of the first and second batteries through the communication interface and displays the acquired information on a display. Therefore, since it is possible to supply power required for driving the device while wearing the HMD, the HMD can be continuously used.

A system and method for variable power transfer in an inductive charging or power system. In accordance with an embodiment the system comprises a pad or similar base unit that contains a primary, which creates an alternating magnetic field. A receiver comprises a means for receiving the energy from the alternating magnetic field from the pad and transferring it to a mobile device, battery, or other device. In accordance with various embodiments, additional features can be incorporated into the system to provide greater power transfer efficiency, and to allow the system to be easily modified for applications that have different power requirements. These include variations in the material used to manufacture the primary and/or the receiver coils; modified circuit designs to be used on the primary and/or receiver side; and additional circuits and components that perform specialized tasks, such as mobile device or battery identification, and automatic voltage or power-setting for different devices or batteries.

Object detection for wireless power transmitters and related systems, methods, and devices are disclosed. A controller for a wireless power transmitter is configured to receive a measurement voltage potential responsive to a tank circuit signal at a tank circuit, provide an alternating current (AC) signal to each of the plurality of transmit coils one at a time, and determine at least one of a resonant frequency and a quality factor (Q-factor) of the tank circuit responsive to each selected transmit coil of the plurality of transmit coils. The controller is also configured to select a transmit coil to use to transmit wireless power to a receive coil of a wireless power receiver responsive to the determined at least one of the resonant frequency and the Q-factor for each transmit coil of the plurality of transmit coils.

A wireless energy transmitting apparatus includes: a direction-finding and location device configured to determine a position of an energy receiving apparatus based on beacon information of the energy receiving apparatus; an energy generation device configured to generate energy, convert the energy into high-frequency electromagnetic waves having a frequency higher than a predetermined frequency threshold, and transmit the high-frequency electromagnetic waves to the energy receiving apparatus; and a processor configured to control the energy generation device to transmit the high-frequency electromagnetic waves to the energy receiving apparatus based on the position of the energy receiving apparatus. The position of the energy receiving end is determined based on the direction-finding and location device, and the energy generation device is controlled to convert the energy into high-frequency electromagnetic waves having a frequency higher than a predetermined frequency and transmit the same to the energy receiving end.

A wireless energy transmitting apparatus includes: a direction-finding and location device configured to determine a position of an energy receiving apparatus based on beacon information of the energy receiving apparatus; an energy generation device configured to generate energy, convert the energy into high-frequency electromagnetic waves having a frequency higher than a predetermined frequency threshold, and transmit the high-frequency electromagnetic waves to the energy receiving apparatus; and a processor configured to control the energy generation device to transmit the high-frequency electromagnetic waves to the energy receiving apparatus based on the position of the energy receiving apparatus. The position of the energy receiving end is determined based on the direction-finding and location device, and the energy generation device is controlled to convert the energy into high-frequency electromagnetic waves having a frequency higher than a predetermined frequency and transmit the same to the energy receiving end.

A receiver for a wireless charging system, capable of receiving power energy using non-contact type magnetic induction, includes a coil capable of receiving the power energy and a part for generating a predetermined output power from the power energy received by the coil, a portable terminal, an NFC coil further provided outside of the coil, and a ferrite sheet further provided at the coil and the NFC coil.

A wireless power system includes a wireless power transmitting device such as a wireless charging mat for charging devices such as a cellular telephone and an earbuds battery case. The earbuds battery case receives earbuds and charges the earbuds from a battery. The wireless charging mat supports bidirectional in-band communications between the cellular telephone and the earbuds battery case. The earbuds battery case provides the cellular telephone with information on the battery charge level associated with the battery in the earbuds battery case and a battery charge level associated with each earbud in the earbuds battery case. The cellular telephone receives battery charge level information through the wireless charging mat and displays corresponding indicators. The earbuds battery case has a visual output device such as a light-emitting diode that is illuminated to indicate that the earbuds battery case is being charged.

A WIRT system uses synchronizable PPM waveforms to convey information and power from an ET to a remote, far-field EH. In so doing, the solution presented herein reduces receiver complexity, optimizes power transfer, and meets information transfer requirements. The synchronizable PPM waveform comprises a plurality of pulsed-modulation symbols, each of which comprises one or more pulses position-modulated responsive to the information to be conveyed to the EH. The ET configures at least one pulse in each symbol of said synchronizable PPM waveform according to one or more synchronization constraints to enable symbol synchronization at the EH. The EH converts the RF power of the received synchronizable PPM waveform to a DC voltage, and synchronizes the received PPM waveform to extract the information in the PPM waveform.

A WIRT system uses synchronizable PPM waveforms to convey information and power from an ET to a remote, far-field EH. In so doing, the solution presented herein reduces receiver complexity, optimizes power transfer, and meets information transfer requirements. The synchronizable PPM waveform comprises a plurality of pulsed-modulation symbols, each of which comprises one or more pulses position-modulated responsive to the information to be conveyed to the EH. The ET configures at least one pulse in each symbol of said synchronizable PPM waveform according to one or more synchronization constraints to enable symbol synchronization at the EH. The EH converts the RF power of the received synchronizable PPM waveform to a DC voltage, and synchronizes the received PPM waveform to extract the information in the PPM waveform.

A wireless power transfer pad for wireless charging of a vehicle electrical storage system. The wireless power transfer pad includes an oscillating electromagnetic field generating device configured for transmitting energy to a wireless power receiver associated with the vehicle. The pad further includes a foreign object detection arrangement including a plurality of foreign object detection coils. The solar panel arrangement includes a photovoltaic substrate with a front side and a rear side, a front side electrode arrangement and a rear side electrode arrangement. The foreign object detection coils are configured to function also as the front side electrode arrangement.