Abstract:
An electrical component with conductive material(s) that is suitable for use within the electromagnetic field path of a wireless power transfer system. The electronic component includes conductive materials that are sufficiently thin to absorb no more than an acceptable amount of the electromagnetic field, yet thick enough to remain sufficiently conductive to perform the desired electrical function. In embodiments in which the wireless power supply delivers up to 20 watts of power, the conductive materials are not substantially thicker than about 1/10 the skin depth of the material at the anticipated wireless power frequency. The electrical component may be disposed at any location between the wireless power supply transmitter and the remote device receiver. The present invention permits the use of a wide rang of electrical components in the field path, such as a display, a sensor or a component capable of selectively operating as both.
Abstract:
A system and method of controlling inductive power transfer in an inductive power transfer system and a method for designing an inductive power transfer system with power accounting. The method of controlling inductive power transfer including measuring a characteristic of input power, a characteristic of power in the tank circuit, and receiving information from a secondary device. Estimating power consumption based on the measured characteristic of tank circuit power and received information and comparing the measured characteristic of input power, the information from the secondary device, and the estimated power consumption to determine there is an unacceptable power loss. The method for designing an inductive power transfer system with power accounting including changing the distance between a primary side and a secondary side and changing a load of the secondary side. For each distance between the primary side and the secondary side and for each load, measuring a circuit parameter on the primary side in the tank circuit and a circuit parameter on the secondary side during the transfer of contactless energy. The method further including selecting a formula to describe power consumption in the system during the transfer of contactless energy based on coefficients and the circuit parameters, and determining the coefficients using the measured circuit parameters.
Abstract:
A wireless remote sensor (110) that is powered by an inductive transmitter (112) and is configured to produce an oscillating wave that varies based on one or more sensed parameters. The oscillating wave is communicated to the inductive transmitter (112) by reflected impedance, where it can be detected to determine the sensed value(s). In another aspect, the present invention provides a wireless remote sensor with a Wheatstone bridge arrangement having an internal resonant circuit to produce an electromagnetic field indicative of the sensed value. In a third aspect, the present invention provides a wireless remote sensor with optical feedback from a reference circuit and a sensor circuit. In a fourth aspect, the present invention provides a wireless remote temperature sensor having coils printed on a material with a high coefficient of thermal expansion so that the size and/or shape of the coils varies as the temperature increases or decreases.
Abstract:
A wireless power transfer component with a selectively adjustable resonator circuit having a Q control subcircuit that varies the Q factor of the resonator circuit to control the amount of power relayed by the resonator circuit. The resonator circuit may be in the wireless power supply, the wireless power receiver, an intermediate resonator or any combination thereof. The resonator circuit may be actively configured based on a feedback circuit. The feedback circuit may sense a characteristic in the secondary circuit or elsewhere and actively operate the control subcircuit based on the sensed characteristic. The feedback circuit may cause the Q control subcircuit to change (reduce or increase) the Q factor when the sensed characteristic crosses a threshold value. The Q control subcircuit may include a variable resistor having a value that can be varied to adjust the Q factor of the resonator circuit.
Abstract:
An item of print media (30) including an inductive secondary (50) for providing power to a load (32). The inductive secondary is responsive to an electromagnetic flux to generate a time-varying current or voltage therein. The current or voltage induced in the inductive secondary directly or indirectly powers the load to thereby enhance the functionality and/or the appeal of the item of print media without significantly adding to its cost. The load can provide a visual and/or auditory output, and can include an electroluminescent display, an e-ink display, a piezo speaker coil, an electrostatic speaker, an OLED, an LED or an LCD display. Embodiments of the invention can be utilized in connection with a wide variety of print media, including for example books, booklets, pamphlets, labels, magazines, manuals, brochures, maps, charts, posters, journals, newspapers or loose leaf pages.