Abstract: Wireless power receivers include a first inductive element featuring a planar coil occupying a first plane and having first and second terminals, a first capacitive element connected to the first terminal, a second capacitive element connected to the first capacitive element at a third terminal and to the second terminal, a rectifier connected to the second terminal and third terminal such that an oscillating magnetic field will induce a current in the first inductive element, resulting in a voltage across the input of the rectifier, a communications modulation circuit, and a layer of magnetic material centered over the planar coil in a second plane parallel to the first plane.

Abstract: A signal filter includes a plurality of laminations forming an annular core, a first bifilar winding wrapped around a first portion of the core, and a second bifilar winding wrapped around a second portion of the core. A wireless power transmitter includes a power input, a power converter coupled to the input and configured to provide high-frequency (HF) current, an output coil, and an output filter between the power converter and the output coil. A wireless power receiver includes an input coil, a power converter coupled to an output and configured to provide current suitable for a load, and an input filter between the input coil and the power converter.

Abstract: A multi-purpose detection circuit for object detection and vehicle position determination is described. For example, the circuit is configurable for detecting foreign metallic objects, living objects, and a vehicle or type of vehicle above an inductive wireless power transmitter. The circuit is also configurable for determining the vehicle's position relative to the inductive wireless power transmitter. An example apparatus includes a measurement circuit including a multiplexer, electrically connected to a plurality of inductive and capacitive sense circuits, for measuring one or more electrical characteristics in each of the inductive and capacitive sense circuits according to a predetermined time multiplexing scheme.

Abstract: A multi-purpose detection circuit for object detection and vehicle position determination is described. For example, the circuit is configurable for detecting foreign metallic objects, living objects, and a vehicle or type of vehicle above an inductive wireless power transmitter. The circuit is also configurable for determining the vehicle's position relative to the inductive wireless power transmitter. An example apparatus includes a measurement circuit including a multiplexer, electrically connected to a plurality of inductive and capacitive sense circuits, for measuring one or more electrical characteristics in each of the inductive and capacitive sense circuits according to a predetermined time multiplexing scheme.

Abstract: A method for detecting a foreign metal object near an inductive wireless power transfer system is based on combined inductive sensing and thermal sensing. A sensing system senses the object based on an inductive or thermal effect. The sensing system includes a sense element which has an electrical characteristic that changes in a presence of the object based on the inductive effect. A mediating heat-sensitive material has a property that varies as a function of temperature and changes the electrical characteristic of the sense element as the property changes. The mediating heat-sensitive material is heated by the foreign object when the foreign object is heated by a magnetic field generated by the wireless power transfer system. A controller measures the electrical characteristic and determines a presence of the object based on the change in the measured electrical characteristics.

Abstract: Systems and methods are described for active harmonics cancellation. A wireless charging apparatus includes a wireless-power transfer circuit comprising a wireless-power transfer coil configured to generate or couple to a magnetic field to transfer or receive power and a plurality of tuning capacitors electrically coupled to the wireless-power transfer coil. The apparatus also includes a power converter circuit electrically coupled to the wireless-power transfer circuit. Additionally, the apparatus includes a signal generation circuit different from the power converter circuit and electrically coupled to one or more nodes between capacitors of the plurality of tuning capacitors. The signal generation circuit is configured to generate and inject a signal into the wireless-power transfer circuit at the nodes between the capacitors. The signal generation circuit includes a rejection filter tuned to an operating frequency of the wireless-power transfer coil.

Abstract: A method for pairing a vehicle to a wireless power transfer (WPT) station and determining their relative location using ultra-wideband (UWB) signaling is described. A Master UWB Tag transmits a Ping message and a Master UWB Anchor transmits a Pong message. The Master Tag and Master Anchor use single-sided two-way ranging (SS-TWR) or double-sided two-way ranging (DS-TWR) to determine the distance between them. The Master Tag and the Master Anchor exchange setup parameters to establish communication between the vehicle and the WPT station and determine their relative position. Each UWB tag and each UWB anchor in the WPT station determine a distance between each tag and each anchor. Based on the distances between tags and anchors and data describing the position of each anchor within the WPT station, a relative position of the vehicle and the WPT station is determined.

Abstract: Disclosed herein are systems and methods for low power excitation of wireless power transmitters configured to transmit high power. The exemplary systems and methods include disabling a power factor correction circuit of the transmitter, and adjusting one or more variable impedance components of the impedance network to obtain a minimum attainable impedance. The variable impedance components can be configured to operate between the minimum attainable impedance and a maximum attainable impedance. The systems and methods can include adjusting a phase shift angle associated with one or more transistors of the inverter and driving the transmitter such that the transmitter resonator coil generates a magnetic flux density less than or equal to a field safety threshold.

Abstract: Techniques for a magnetic-shielding-and-enhancement winding are disclosed. The magnetic-shielding-and-enhancement winding is a winding of a multi-turn coil that is on a separate layer from other windings of the coil (e.g., on a general winding layer). The magnetic-shielding-and-enhancement winding provides magnetic shielding to reduce localized multiplicative effects of aggregate fields generated by the windings of the coil on the general winding layer and simultaneously acts as one or more turns of the winding structure to enhance the field in a desirable manner.

Abstract: A wireless charging assembly for an electric vehicle, including a control unit, a charging pad for mounting to a floor and spaced from the control unit and a conduit extending between the control unit and the charging pad. The conduit has a first internal passageway for delivery of cooling air from an airflow generator to the charging pad for cooling the charging pad and a second internal passageway for return of cooling air from the charging pad back to the airflow generator. The first and second internal passageways and the charging pad forming a substantially closed circuit that is closed to atmosphere to prevent ingress of external matter into the first and second internal passageways and the charging pad. The conduit has a third internal passageway for accommodating one or more cables extending from the control unit to the charging pad.

Abstract: Techniques for a magnetic-shielding-and-enhancement winding are disclosed. The magnetic-shielding-and-enhancement winding is a winding of a multi-turn coil that is on a separate layer from other windings of the coil (e.g., on a general winding layer). The magnetic-shielding-and-enhancement winding provides magnetic shielding to reduce localized multiplicative effects of aggregate fields generated by the windings of the coil on the general winding layer and simultaneously acts as one or more turns of the winding structure to enhance the field in a desirable manner.

Abstract: A wireless power transmitter includes a first inductive element featuring a planar coil occupying a first plane and having first and second terminals, a first capacitive element connected to the first terminal, an inverter configured to provide an oscillating voltage signal to the first inductive element, through the first capacitive element, such that the first inductive element generates an oscillating magnetic field for transmitting power in response to the oscillating voltage signal, and a layer of magnetic material, disposed over the planar coil in a second plane parallel to the first plane.

Abstract: In certain aspects, an enclosure for a wireless power transfer pad is disclosed. The enclosure includes a cover shell configured to be positioned over a portion of the wireless power transfer pad configured to face a wireless power receiver when wirelessly transferring power, wherein at least a portion of the cover shell is made of a heat resistant material.

Abstract: Exemplary embodiments are directed to wireless charging and wireless power alignment of wireless power antennas associated with a vehicle. A wireless power charging apparatus includes an antenna including first and second orthogonal magnetic elements for detecting a horizontal component of a magnetic field generated from a second charging base antenna. A processor determines a directional vector between the antennas.

Abstract: A multi-purpose detection circuit for object detection and vehicle position determination is described. For example, the circuit is configurable for detecting foreign metallic objects, living objects, and a vehicle or type of vehicle above an inductive wireless power transmitter. The circuit is also configurable for determining the vehicle's position relative to the inductive wireless power transmitter. An example apparatus includes a measurement circuit including a multiplexer, electrically connected to a plurality of inductive and capacitive sense circuits, for measuring one or more electrical characteristics in each of the inductive and capacitive sense circuits according to a predetermined time multiplexing scheme.

Abstract: This disclosure provides systems, methods and apparatus for detecting foreign objects. In one aspect an apparatus for detecting a presence of an object is provided. The apparatus includes a resonant circuit having a resonant frequency. The resonant circuit includes a sense circuit including an electrically conductive structure. The apparatus further includes a coupling circuit coupled to the sense circuit. The apparatus further includes a detection circuit coupled to the sense circuit via the coupling circuit. The detection circuit is configured to detect the presence of the object in response to detecting a difference between a measured characteristic that depends on a frequency at which the resonant circuit is resonating and a corresponding characteristic that depends on the resonant frequency of the resonant circuit. The coupling circuit is configured to reduce a variation of the resonant frequency by the detection circuit in the absence of the object.

Abstract: A multi-purpose detection circuit for object detection and vehicle position determination is described. For example, the circuit is configurable for detecting foreign metallic objects, living objects, and a vehicle or type of vehicle above an inductive wireless power transmitter. The circuit is also configurable for determining the vehicle's position relative to the inductive wireless power transmitter. An example apparatus includes a measurement circuit including a multiplexer, electrically connected to a plurality of inductive and capacitive sense circuits, for measuring one or more electrical characteristics in each of the inductive and capacitive sense circuits according to a predetermined time multiplexing scheme.

Abstract: The disclosure features systems and methods for protecting transistors of a wireless power receiver. Systems can include a gate driver configured provide a control signal to control switching of the transistor gate such that power is transmitted to a load coupled to the receiver; and a controller coupled to the gate driver and configured to generate a protection signal. The protection signal can include (i) a fault signal indicating a fault in one or more components of the receiver; (ii) a signal indicating that the transistor gate should be latched; and/or (ii) at least one undervoltage signal indicating that an undervoltage condition exists in a power supply of the gate driver. Based on the generated protection signal, the gate driver can be configured to adjust the provided control signal to latch the transistor gate such that power is not transmitted to the load.