Abstract: A load independent inverter comprises a switched mode zero-voltage switching (ZVS) amplifier. The switched mode ZVS amplifier comprising: a pair of circuits comprises: at least a transistor and at least a capacitor arranged in parallel; and at least an inductor arranged in series with the transistor and capacitor. The amplifier further comprises only one ZVS inductor connected to the pair of circuits; and at least a pair of capacitors connected to the ZVS inductor and arranged in series with at least an inductor and at least a resistor.

Abstract: A load independent inverter comprises a switched mode zero-voltage switching (ZVS) amplifier. The switched mode ZVS amplifier comprising: a pair of circuits comprises: at least a transistor and at least a capacitor arranged in parallel; and at least an inductor arranged in series with the transistor and capacitor. The amplifier further comprises only one ZVS inductor connected to the pair of circuits; and at least a pair of capacitors connected to the ZVS inductor and arranged in series with at least an inductor and at least a resistor.

Abstract: An alignment device comprises a coil configured to generate an induced voltage from a magnetic field, or an electrode configured to generate an induced voltage from an electric field. The alignment device further comprises a comparator configured to compare the induced voltage to a threshold voltage and activate an indicator based on the comparison.

Abstract: An alignment device comprises a coil configured to generate an induced voltage from a magnetic field, or an electrode configured to generate an induced voltage from an electric field. The alignment device further comprises a comparator configured to compare the induced voltage to a threshold voltage and activate an indicator based on the comparison.

Abstract: A differential rectifier for use in a receiver for receiving wireless power via inductive coupling comprises first and second capacitors; first and second switching elements; and first and second inductors. The first capacitor and first inductor are electrically connected in series, and the second capacitor and second inductor are electrically connected in series. The first switching element is electrically connected between the first capacitor and first inductor in parallel, and the second switching element is electrically connected between the second capacitor and second inductor in parallel. The first capacitor electrically is connected to a terminal of a coil for receiving power wirelessly via inductive coupling, and the second capacitor is electrically connected to another terminal of a coil for receiving power wirelessly via inductive coupling. The first and second switching elements are electrically connected to a tap of a coil for receiving power wirelessly via inductive coupling.

Abstract: An auxiliary inverter for use with a main inverter of a transmitter of a wireless power transfer system comprises: a coupling element; an output network electrically connected to the coupling element; and an adjustable power source electrically connected to the coupling element via the output network, an input voltage to the coupling element based on a detected signal. The coupling element is configured to induce a voltage in the main inverter of the transmitter of the wireless power transfer system to manage reflected impedance at the main inverter. The induced voltage is based on the input voltage to the coupling element.

Abstract: Disclosed herein is a rectifier circuit for receiving an AC signal from a receiver coil in an inductive power transfer system. The circuit is configured to operate at an operating frequency. The circuit comprises a Class-E rectifier; an AC signal supplier configured to supply an AC signal to the rectifier circuit; and a resonant network having an inductor and a capacitor. The resonant network has a resonant frequency, and the ratio of the resonant frequency to the operating frequency is within the range of 1.75 to 3.

Abstract: An apparatus for use in a magnetic induction wireless power transfer system comprises at least one booster coil positioned adjacent an active coil of a magnetic induction wireless power transfer system and a capacitor electrically connected to the booster coil. A capacitance of the capacitor is selected such that a current in the booster coil is approximately equal to a current in the active coil during wireless power transfer. The apparatus may comprise at least one shielding coil positioned adjacent an active coil of a magnetic induction wireless power transfer system, a capacitor electrically connected to the shielding coil, and a conductor positioned adjacent the shielding coil opposite the active coil. The conductor encompasses the shielding coil.

Abstract: The present disclosure relates to a wireless power transmission system (100) comprising a wireless power transmission device (108), and a method of identifying the presence of a foreign object within wireless power transmission range of the wireless power transmission device (108). The wireless power transmission system (100) comprises a wireless power transmission device (108) for wirelessly transmitting power to an electronic receiver device (102) and a digital subsystem comprising an analog to digital converter “ADC” and a processor. The ADC is configured to digitise a waveform associated with the wireless power transmission device (108), to produce a source-drain waveform vector. The processor is configured to apply a classifier to the source-drain waveform vector; and determine, based on a numerical output of the classifier, whether a foreign object is present within wireless power transmission range of the wireless power transmission device (108).

Abstract: An alignment device comprises a coil configured to generate an induced voltage from a magnetic field, or an electrode configured to generate an induced voltage from an electric field. The alignment device further comprises a comparator configured to compare the induced voltage to a threshold voltage and activate an indicator based on the comparison.

Abstract: A load independent inverter comprises a switched mode zero-voltage switching (ZVS) amplifier. The switched mode ZVS amplifier comprising: a pair of circuits comprises: at least a transistor and at least a capacitor arranged in parallel; and at least an inductor arranged in series with the transistor and capacitor. The amplifier further comprises only one ZVS inductor connected to the pair of circuits; and at least a pair of capacitors connected to the ZVS inductor and arranged in series with at least an inductor and at least a resistor.

Abstract: An inverter for inductive power transfer is disclosed.

Abstract: A rectifier for wireless power transfer is disclosed.

Abstract: Disclosed herein is a rectifier circuit for receiving an AC signal from a receiver coil in an inductive power transfer system. The circuit is configured to operate at an operating frequency. The circuit comprises a Class-E rectifier; an AC signal supplier configured to supply an AC signal to the rectifier circuit; and a resonant network having an inductor and a capacitor. The resonant network has a resonant frequency, and the ratio of the resonant frequency to the operating frequency is within the range of 1.75 to 3.

Abstract: A load-independent Class EF inverter may maintain ZVS operation, and produce a constant output current, rather than a constant output voltage, regardless of the load resistance. A constant output current allows the inverter to operate efficiently for a load range from zero resistance (short circuit) to a certain maximum load resistance, making the inverter more suitable as a coil driver for an IPT system. The resonant frequency of the resonant circuit may be tuned to a non-integer multiple of a switching frequency.

Abstract: A rectifier for wireless power transfer is disclosed.

Abstract: An inverter for inductive power transfer is disclosed.

Abstract: A load-independent Class EF inverter may maintain ZVS operation, and produce a constant output current, rather than a constant output voltage, regardless of the load resistance. A constant output current allows the inverter to operate efficiently for a load range from zero resistance (short circuit) to a certain maximum load resistance, making the inverter more suitable as a coil driver for an IPT system. The resonant frequency of the resonant circuit may be tuned to a non-integer multiple of a switching frequency.