Abstract: In one embodiment, a wireless power transfer system comprises a transmitter coil structure comprising a first transmitter coil, and a second transmitter coil coupled to the first transmitter coil in such a way that when a first current flows in the first transmitter coil in a first spatial direction the first current flows in the second transmitter coil in a second spatial direction different from the first spatial direction, a foreign object sensor coil structure comprising a first sensor coil having a central axis in common with the first transmitter coil, and a second sensor coil coupled in series to the first sensor coil, the second sensor coil having a central axis in common with the second transmitter coil, the first sensor coil coupled to the second sensor coil in such a way that when a first voltage induced in the first sensor coil has a first polarity a second voltage induced in the second sensor coil has a second polarity different from the first polarity, a voltage detector coupled to the foreign o

Abstract: In one embodiment, an array for wireless power transfer includes a plurality of tuned resonant microcell structures (hereinafter “microcell”). Each microcell comprises at least one coil, at least one capacitor, and two connection points. Each microcell in the array is configured to be individually tuned to the same resonant frequency. The microcells in the array are connected together in a series through the two connection points of each microcell in such a way that the array is configured to have the same resonant frequency as each of the individually tuned microcells. The multiple coil structure may be connected to a power source and can be implemented in a wireless power transmitter.

Abstract: In one embodiment, a wireless power transfer system comprises a transmitter coil structure comprising a first transmitter coil, and a second transmitter coil coupled to the first transmitter coil in such a way that when a first current flows in the first transmitter coil in a first spatial direction the first current flows in the second transmitter coil in a second spatial direction different from the first spatial direction, a foreign object sensor coil structure comprising a first sensor coil having a central axis in common with the first transmitter coil, and a second sensor coil coupled in series to the first sensor coil, the second sensor coil having a central axis in common with the second transmitter coil, the first sensor coil coupled to the second sensor coil in such a way that when a first voltage induced in the first sensor coil has a first polarity a second voltage induced in the second sensor coil has a second polarity different from the first polarity, a voltage detector coupled to the foreign o

Abstract: In one embodiment, a wireless power transmitter comprises a transmitter coil structure comprising a magnetic layer having a geometric center line, the magnetic layer being curved symmetrically about a geometric center line, a first coil coupled to a second coil, the first coil and second coil wound in such a way that when a current flows in the first coil in a first spatial direction the current flows in the second coil in a second spatial direction, the first coil and the second coil disposed on the magnetic layer substantially symmetrically about the geometric center line of the magnetic layer, a power circuit configured to provide a time-varying current to the transmitter coil structure; and a housing including an outer surface having a convex shape, the transmitter coil structure being disposed underneath the outer surface of the housing.

Abstract: In one embodiment, a multiple interleaved coil structure for wireless power transfer includes a plurality of incomplete coils, each of the plurality of incomplete coils configured such that an alternating current flowing in the incomplete coil produces a magnetic field, and at least one interconnect between the plurality of incomplete coils, the at least one interconnect including a plurality of conductors arranged in such a way that the alternating current flowing in the plurality of conductors does not produce a magnetic field. Each of the plurality of incomplete coils includes a plurality of non-contiguous segments arranged in such a way that the incomplete coil will emit magnetic flux in response to an applied alternating current. The multiple interleaved coil structure can be implemented in a wireless power transmitter or a wireless power receiver.

Abstract: In one embodiment, a wireless power alignment guide uses multiple coils and a detector circuit to determine an offset between a wireless power receiver and a wireless power transmitter. A transmitter generates a magnetic field that causes a first time-varying current to flow in a first coil and a second time-varying current to flow in a second coil of the wireless power alignment guide. The first time-varying current can flow to the second coil and the second time-varying current can flow to the first coil. A detector circuit detects a voltage resulting from the first time-varying current and the second time-varying current and determines an offset so the user can center the receiver with the transmitter. By correcting any offset between the receiver and the transmitter, greater amounts of power can be transferred to the receiver in comparison to a receiver that is offset from a transmitter.