Abstract: Regulating wireless power transfer (WPT) from a wireless power transmitter to a wireless power receiver (PRx) can include receiving from the PRx a plurality of indications of receiver power including corresponding rectifier voltage and rectifier current; analyzing the received plurality of indications of receiver power to compute one or more coefficients for predicting power loss, wherein the one or more coefficients include a first coefficient relating to rectifier voltage and a second coefficient relating to rectifier current; determining a sensitivity of a matrix comprising the rectifier voltages and rectifier currents of the received plurality of indications of receiver power; and transmitting power to the PRx in accordance with a power limit, wherein: if the determined sensitivity is greater than a first threshold, the power limit is a first power limit; and if the determined sensitivity is less than the first threshold, the power limit is a second, higher power limit.

Abstract: A wireless charging system may include a wireless power receiving device that receives wireless power signals from a wireless power transmitting device. The wireless power transmitting device may transmit cooling capabilities information to the wireless power receiving device. The wireless power receiving device may transmit a cooling profile request to the wireless power transmitting device.

Abstract: A system for inductive power transfer that may selectively transmit power in a plurality of modes based on characteristics of a power receiver and determine which transmitter coils to drive based on received signal strength information. The inductive power transfer transmitter may detect characteristics of the power receiver in order to control the mode of the power transfer and selectively control which transmitter coils are driven based on signal strength information received from a power receiver. The power transmitter may have slugs formed of a magnetically permeable material within common coil winding openings and the transmitter coils may consists of a plurality of parallel windings.

Abstract: An inductive power receiver including a switch mode regulator to control the power flow from a power receiving coil and a modulator to communicate to an inductive power transmitter via the power receiving coil. The switch mode regulator operates in a different modes during transmitting and non-transmitting periods.

Abstract: An inductive power transmitter and an inductive power receiver include communication circuitry to communicate using modulation of the power transfer field. The inductive power transmitter or the inductive power receiver includes monitoring circuitry to determine a communication fault condition. If a communication fault condition is determined, a converter of the inductive power transmitter or inductive power receiver can adjust a control parameter.

Abstract: A wireless power transmitting device transmits wireless power signals to a wireless power receiving device using an output circuit that includes a wireless power transmitting coil. Measurement circuitry is coupled to the output circuit to help determine whether the wireless power receiving device is present and ready to accept transmission of wireless power. Oscillator circuitry for supplying signals to the output circuitry while making measurements with the measurement circuitry is coupled to the output circuit using an impedance injection network. The impedance injection network includes an inductor and a resistor coupled in series. Control circuitry opens a transistor in the output circuit when making measurements with the measurement circuitry and closes the transistor when transmitting the wireless power signals.

Abstract: A system for inductive power transfer that may selectively transmit power in a plurality of modes based on characteristics of a power receiver and determine which transmitter coils to drive based on received signal strength information. The inductive power transfer transmitter may detect characteristics of the power receiver in order to control the mode of the power transfer and selectively control which transmitter coils are driven based on signal strength information received from a power receiver. The power transmitter may have slugs formed of a magnetically permeable material within common coil winding openings and the transmitter coils may consists of a plurality of parallel windings.

Abstract: A system for inductive power transfer that may selectively transmit power in a plurality of modes based on characteristics of a power receiver and determine which transmitter coils to drive based on received signal strength information. The inductive power transfer transmitter may detect characteristics of the power receiver in order to control the mode of the power transfer and selectively control which transmitter coils are driven based on signal strength information received from a power receiver. The power transmitter may have slugs formed of a magnetically permeable material within common coil winding openings and the transmitter coils may consists of a plurality of parallel windings.

Abstract: An inductive power transmitter and an inductive power receiver include communication circuitry to communicate using modulation of the power transfer field. The inductive power transmitter or the inductive power receiver includes monitoring circuitry to determine a communication fault condition. If a communication fault condition is determined, a converter of the inductive power transmitter or inductive power receiver can adjust a control parameter.

Abstract: An inductive power transmitter having a plurality of transmitting coils for generating an alternating magnetic field arranged in a row with each transmitting coil partially overlapping with adjacent transmitting coils in the row. A transmitting circuit connected to each transmitting coil may drive the transmitting coils so that each transmitting coil's alternating magnetic field is phase shifted with respect to the alternating magnetic field of adjacent transmitting coils in the row or so that the alternating magnetic field generated by the transmitting coils travels along a charging surface.

Abstract: A system for inductive power transfer that may selectively transmit power in a plurality of modes based on characteristics of a power receiver and determine which transmitter coils to drive based on received signal strength information. The inductive power transfer transmitter may detect characteristics of the power receiver in order to control the mode of the power transfer and selectively control which transmitter coils are driven based on signal strength information received from a power receiver. The power transmitter may have slugs formed of a magnetically permeable material within common coil winding openings and the transmitter coils may consists of a plurality of parallel windings.

Abstract: A wireless power transmitting device transmits wireless power signals to a wireless power receiving device using output circuitry that includes an array of wireless power transmitting coils that form a wireless charging surface. During wireless power transmission operations, wireless power signals are transmitted from the array of coils to a wireless power receiving device on the charging surface. Inductance measurement circuitry such as impulse response measurement circuitry and other measurement circuitry is coupled to the output circuitry. Control circuitry in the wireless power transmitting device analyzes signals from the measurement circuitry to produce two-dimensional signal profiles across the wireless charging surface and to compare patterns in these signal profiles to predetermined signal patterns associated with the presence of known power receiving equipment on the wireless charging surface. Based on the analysis, charging parameters may be adjusted or other actions taken.

Abstract: There is provided a contactless power system, power receiver and method of operating such, in which the power receiver of the system is configured to receive power transmitted by a power transmitter of the system via contactless electromagnetic coupling of respective receiving and transmitting coils. The power receiver further has circuitry for reflecting a unique magnetic signal to the transmitting coil of the power transmitter upon receipt of a power pulse by the receiver coil of the power receiver.

Abstract: A wireless power transmitting device transmits wireless power signals to a wireless power receiving device using an output circuit that includes a wireless power transmitting coil. Measurement circuitry is coupled to the output circuit to help determine whether the wireless power receiving device is present and ready to accept transmission of wireless power. Oscillator circuitry for supplying signals to the output circuitry while making measurements with the measurement circuitry is coupled to the output circuit using an impedance injection network. The impedance injection network includes an inductor and a resistor coupled in series. Control circuitry opens a transistor in the output circuit when making measurements with the measurement circuitry and closes the transistor when transmitting the wireless power signals.

Abstract: A wireless power transmitting device transmits wireless power signals to a wireless power receiving device using output circuitry that includes an array of wireless power transmitting coils that form a wireless charging surface. During wireless power transmission operations, wireless power signals are transmitted from the array of coils to a wireless power receiving device on the charging surface. Inductance measurement circuitry such as impulse response measurement circuitry and other measurement circuitry is coupled to the output circuitry. Control circuitry in the wireless power transmitting device analyzes signals from the measurement circuitry to produce two-dimensional signal profiles across the wireless charging surface and to compare patterns in these signal profiles to predetermined signal patterns associated with the presence of known power receiving equipment on the wireless charging surface. Based on the analysis, charging parameters may be adjusted or other actions taken.

Abstract: An inductive power transfer device including: a resonant circuit, having a power transfer coil and a power transfer capacitor; a coupling coil, magnetically-coupled to the power transfer coil; a variable impedance; and a controller configured to determine the impedance value of the variable impedance based on predetermined criteria including: substantially regulating power provided to a load; tuning the resonant circuit resonant frequency substantially to a predetermined frequency; adjusting a frequency of a magnetic field associated with the power transfer coil; and/or adjusting an impedance reflected by the power transfer coil to a corresponding coupled power transfer coil.

Abstract: An inductive power receiver comprising: a power receiving coil; a power regulation stage, configured to connect in parallel with the power receiving coil, and a tuning capacitance configured to connect in series between the power receiving coil and a rectification stage and/or a load, wherein the power regulator is configured with a short circuit control strategy.

Abstract: An inductive power receiver including a switch mode regulator to control the power flow from a power receiving coil and a modulator to communicate to an inductive power transmitter via the power receiving coil. The switch mode regulator operates in a different modes during transmitting and non-transmitting periods.

Abstract: A system for inductive power transfer that may selectively transmit power in a plurality of modes based on characteristics of a power receiver and determine which transmitter coils to drive based on received signal strength information. The inductive power transfer transmitter may detect characteristics of the power receiver in order to control the mode of the power transfer and selectively control which transmitter coils are driven based on signal strength information received from a power receiver. The power transmitter may have slugs formed of a magnetically permeable material within common coil winding openings and the transmitter coils may consists of a plurality of parallel windings.

Abstract: An inductive power transfer device including: a resonant circuit, having a power transfer coil and a power transfer capacitor; a coupling coil, magnetically-coupled to the power transfer coil; a variable impedance; and a controller configured to determine the impedance value of the variable impedance based on predetermined criteria including: substantially regulating power provided to a load; tuning the resonant circuit resonant frequency substantially to a predetermined frequency; adjusting a frequency of a magnetic field associated with the power transfer coil; and/or adjusting an impedance reflected by the power transfer coil to a corresponding coupled power transfer coil.