Abstract: A method of operating a wireless-power receiver comprises: determining a first resonant frequency of a resonant circuit, of the wireless-power receiver, corresponding to a first time at which the wireless-power receiver is disposed at a first longitudinal offset from a power transmitter, the first longitudinal offset being relative to a length of a device containing the wireless-power receiver; determining a second resonant frequency of the resonant circuit, corresponding to a second time at which the wireless-power receiver is disposed at a second longitudinal offset from the power transmitter, the second longitudinal offset being relative to the length of the device containing the wireless-power receiver, and the first longitudinal offset being different from the second longitudinal offset; and determining a lateral misalignment of the wireless-power receiver relative to a wireless-power transmitter based on the first resonant frequency and the second resonant frequency.

Abstract: The present disclosure describes aspects of a vehicle-based beacon mode for wireless electric vehicle charging. In some aspects, a circuit for receiving wirelessly transferred power includes a coil connected to boost circuitry configured to convert received power to a form suitable for storage. The circuit also includes beacon circuitry connected to a voltage source that, in combination with portions of the boost circuitry, enables current to be driven into the coil to generate a beacon signal. Based on this beacon signal, a base charging unit can detect the presence of the circuit and initiate the wireless transmission of power to the circuit without additional out-of-band communication. Further, the beacon circuitry may be compatible with, or protected from, current of the received power such that the circuit can seamlessly transition from generating the beacon signal to converting the received power without active reconfiguration, synchronization, or state control.

Abstract: Systems and methods are described that increase pad efficiency and robustness. These systems and methods balance magnetic flux density in ferrite strips in a WEVC pad to reduce heat produced in high-flux areas of the ferrite strips. Aspects include controlled spacing between ferrite strips of a WEVC pad and intentional gaps located within high-flux areas in the strips. The sizes of the intentional gaps are determined in relation to the size of the spacing between the strips. In addition, ribs are disposed between the strips and connected to a backplate to provide structural rigidity and robustness to the pad.

Abstract: Systems and methods are described that reduce magnetic flux density proximate to a wireless charging pad, such as a WEVC pad. These systems and methods control peak magnetic flux density in air around a WEVC pad to reduce potentially dangerous heat produced in foreign metal objects affected by a magnetic field generated by a coil of the WEVC pad. Controlling the peak magnetic flux density results in a safer WEVC pad. Aspects include ferrite tiles being separated by gaps having predefined sizes to increase a magnetic reluctance of a path of the magnetic flux through the ferrite tiles, which reduces a peak magnetic flux density experienced in areas proximate to the coil. In addition, the ferrite tiles can be arranged such that a combination of gaps are aligned with a region overlapping the coil.

Abstract: One aspect provides a wireless power transmitter. The wireless power transmitter includes a transmit antenna configured to generate a field for wireless transmit power in both a first and second configuration. The wireless power transmitter further includes a first capacitor. The wireless power transmitter further includes at least one switch configured to selectively connect the first capacitor in one of the first and second configuration, the first capacitor being in parallel with the transmit antenna in the first configuration and in series with the transmit antenna in the second configuration. The wireless power transmitter further includes a second capacitor in parallel with the transmit antenna and a transformer configured to operate at a first turns-ratio in the first configuration and a second turns-ratio in the second configuration, the first turns-ratio being lower than the second turns-ratio.

Abstract: An apparatus for wirelessly transferring power is provided. The apparatus comprises a first coupler, a second coupler, and a third coupler overlapping at least the first coupler. The apparatus further comprises a ferrimagnetic structure comprising a first portion disposed under the first coupler, a second portion disposed under the second coupler, and a gap defined between the first coupler and the second coupler, the gap physically separating the first portion from the second portion. One or both of the first portion and the second portion comprises a first plurality of ferrimagnetic strips interleaved with a second plurality of ferrimagnetic strips configured to attenuate a magnetic flux passing between the first and second couplers. The first plurality of ferrimagnetic strips are interleaved with the second plurality of ferrimagnetic strips under at least a portion of the first coupler that is overlapped by the third coupler.

Abstract: Systems, methods, and apparatus are disclosed for power transfer including a plurality of coil structures located over a ferrite element, the plurality of coil structures configured to generate a high flux region and a low flux region, the low flux region being located between the plurality of coil structures, and a tuning capacitance located directly over the ferrite element in the low flux region.

Abstract: An apparatus for wirelessly transferring charging power is provided. The apparatus comprises a first coil, as second coil, a ferrite structure positioned on one side of the first coil and the second coil. The ferrite structure includes a first angled surface at an outer side of the first coil and a second angled surface at an outer side of the second coil. The ferrite structure further includes a substantially flat surface at an inner side of the first coil and an inner side of the second coil. The first angled surface and the second angled surface are at an angle to the flat surface.

Abstract: Systems, methods and apparatus for wireless power transfer and particularly wireless power transfer to remote systems such as electric vehicles are disclosed. In one aspect an induction coil is provided comprising a plurality of substantially co-planar coils formed from one or more lengths of conducting material, each length of conducting material being electrically connectable at each end to a power source or battery, and wherein at least one of the lengths of conducting material is continuously wound around two or more of the coils. In another aspect, a method is provided for forming such an induction coil. In yet another aspect, a switching device is operable to alter the configuration of the coils, for example in response to a detected characteristic of another induction coil or device coupled thereto.

Abstract: Systems, methods, and apparatuses utilizing a bipolar double D vehicle coupler in wireless power transfer applications are described herein. Some implementations may include an apparatus for wireless power transfer. The apparatus comprises a first coil and a second coil connected in series to form a first circuit. The first coil does not overlap the second coil. The apparatus comprises a third coil and a fourth coil electrically connected in series to form a second circuit. The third coil does not overlap the fourth coil. At least a portion of the first circuit overlaps at least a portion of the second circuit. The first circuit is substantially magnetically decoupled from the second circuit.

Abstract: Aspects of this disclosure include an apparatus configured to and methods for the transfer of wireless power. The apparatus comprises a first coil enclosing a first area. The apparatus also comprises a second coil enclosing a second area different than the first area, the second coil positioned to be at least partially coplanar with the first coil. The apparatus further comprises a ferrite material and a third coil and a fourth coil each wound about the ferrite material, the third coil at least partially enclosed by the first coil and the fourth coil at least partially enclosed by the second coil.

Abstract: According to some implementations, an apparatus for transmitting charging power wirelessly to a load is provided. The apparatus comprises at least one ferrite structure comprising a first ferrite portion, a second ferrite portion comprising at least a first ferrite leg, a second ferrite leg, and a third ferrite leg, each physically separated from the first ferrite portion by a first distance, and a third ferrite portion positioned between the second ferrite leg and the first ferrite portion and physically contacting the second ferrite leg. The at least one ferrite structure further comprises a coil wound around the second ferrite leg and configured to generate an alternating current under influence of an alternating magnetic field.

Abstract: Systems, methods, and apparatus for partial electronics integration in vehicle pads for wireless power transfer applications are provided. In one aspect, an apparatus for wirelessly receiving charging power is provided. The apparatus comprises a first enclosure including at least a receive coupler configured to generate an alternating current under the influence of an alternating magnetic field in a first enclosure. The first enclosure further includes a rectifier circuit configured to modify the alternating current to produce a direct current for output from the first enclosure to a controller circuit in a disparately located second enclosure. The apparatus further comprises at least one direct current inductor configured to receive the direct current from the rectifier circuit. In some implementations, the apparatus further comprises the controller circuit in the second enclosure. The controller circuit is configured to selectively provide the direct current to a battery.

Abstract: Systems and methods in accordance with particular embodiments provide for alignment of an electric vehicle induction coil with a base system induction coil through a determination of the phase of a base system induction coil current signal. In certain embodiments, an electric vehicle induction coil that receives a transmission signal can be determined to be in greater alignment with a base system induction coil that transmits the transmission signal as the phases of the current signals at the base system induction coil and the electric vehicle induction coil converge. One embodiment includes a method of receiving wireless power, including detecting a transmission signal in a wireless power transmission, the transmission signal comprising periodic variations between a first frequency and a second frequency. The method further includes determining a phase of a base system induction coil signal based on the detected transmission signal.

Abstract: A magnetic flux pad (BPP) is provided for receiving magnetic flux. The pad may be used with an inductive power transfer system, and comprises a magnetically permeable core (4) and two substantially flat overlapping coils (2, 3) magnetically associated with the core (4).

Abstract: An apparatus for wirelessly transferring power to a receive coupler is provided. The apparatus comprises a first coupler connected to a second coupler. The apparatus further comprises a third coupler overlapping the first and second couplers. The apparatus further comprises a controller configured to receive power from at least one power supply, provide a first current to the first coupler and the second coupler in a first charging mode, and provide the first current to the first coupler and the second coupler and provide a second current to the third coupler in a second charging mode. A magnetic flux generated by the first current passing through a first portion is constructively additive with a magnetic flux generated by the first current passing through a second portion.

Abstract: Systems and methods for dynamically tuning reactive power in an inductive power transfer system are disclosed. The system comprises a first plurality of coils operably coupled to a respective ferromagnetic material, configured to receive wireless power via the ferromagnetic material from a power source. The system further comprises a plurality of switches configured to selectively control power received by certain of the first plurality of coils. The system further comprises a second plurality of coils configured to receive current from respective ones of the first plurality of coils and deliver wireless power to a wireless power receiver. The system further comprises at least one control unit configured to selectively activate the switches. The switches may be set to provide power from the power source to a portion of the plurality of the second coils or selectively increase or decrease the reactive power load of the power source.

Abstract: Methods and apparatuses for thermal dissipation in vehicle pads for wireless power transfer applications are provided. In some implementations, an apparatus for wirelessly receiving charging power is provided. The apparatus comprises at least one receive coil configured to wirelessly receive the charging power. The apparatus further comprises a plurality of electrical components configured to convert the charging power to a direct current. The apparatus further comprises a primary heat sink comprising a plurality of fins configured to dissipate heat generated by the plurality of electrical components. The plurality of fins are disposed adjacent to the plurality of electrical components. The apparatus further comprises at least one thermally conductive structure configured to physically connect at least some of the plurality of electrical components to the primary heat sink.

Abstract: A magnetic flux pad (BPP) is provided for receiving magnetic flux. The pad may be used with an inductive power transfer system, and comprises a magnetically permeable core (4) and two substantially flat overlapping coils (2, 3) magnetically associated with the core (4).

Abstract: Systems, methods, and apparatuses utilizing a bipolar double D vehicle coupler in wireless power transfer applications are described herein. Some implementations may include an apparatus for wireless power transfer. The apparatus comprises a first coil and a second coil connected in series to form a first circuit. The first coil does not overlap the second coil. The apparatus comprises a third coil and a fourth coil electrically connected in series to form a second circuit. The third coil does not overlap the fourth coil. At least a portion of the first circuit overlaps at least a portion of the second circuit. The first circuit is substantially magnetically decoupled from the second circuit.