Abstract: A multi-coil placement method of a wireless charging system is disclosed. The method may include obtaining a width parameter of an effective charging area a and a width parameter of a power transmitter coil b, calculating a ratio of the width parameters a/b, determining a shape, size and number of layers of mesh cells based on the ratio of a/b, determining a layout of the mesh cells, covering a required charging area using the mesh cells based on the determined shape, size, number of layers, and layout, and replacing the mesh cells with the power transmitter coils.

Abstract: Methods and devices for increasing power delivery efficiency of wireless power transfer systems are disclosed. A wireless power transfer system may include a power transmitter system and a power receiver system. The power transmitter system may comprise a power amplifier, a power transmitter, a controller, and a sensing circuit. The power amplifier may be configured to receive an input power. The power transmitter system may include a transmitter-side coil configured to wirelessly couple to a receiver-side coil of the power receiver system. The controller may be configured to set a voltage and a frequency of the power transmitter system based on output power information of the power receiver system to increase wireless power delivery efficiency of the wireless power transfer system. The sensing circuit may be configured to determine the output power information of the power receiver system.

Abstract: Methods, systems, and devices for wirelessly providing power to devices using a non-resonant power receiver are disclosed. A transmitter-side inductor may be inductively coupled to a receiver-side inductor. The transmitter-side inductor and one or more transmitter-side matching capacitors may be included in a power transmitter. The receiver-side inductor may be included in a power receiver. The power receiver may not include a receiver-side matching capacitor. Power from the power transmitter may be provided to the power receiver via the inductive coupling between the transmitter-side inductor and the receiver-side inductor. The power receiver may provide a reflected impedance including a real part and an imaginary part to the power transmitter. The transmitter-side matching capacitor(s) may compensate for the imaginary part of the reflected impedance.

Abstract: A sparse routing coil structure for a magnetic coil in a wireless charging system is disclosed. The sparse routing coil structure may include a magnetic coil routed by turns of a wire and a turn spacing S between adjacent turns of the wire. The turn spacing S may be a space between adjacent turns of the wire, and a turn width is denoted as W. A ratio of W/S may be not larger than 10.

Abstract: A method for manufacturing a magnetic coil in a wireless charging system is disclosed. The coil may comprise a wire with a rectangular cross section. The method may include feeding a wire into a routing device which includes three winding wheels; routing the wire into a magnetic coil by changing positions of the winding wheels; and assembling the magnetic coil by pressing and attaching the magnetic coil to a coil holder.

Abstract: A method for adaptively optimizing wireless charging efficiency is disclosed. The method may comprise providing an input power to a power transmitter, the power transmitter comprising a transmitter-side coil wirelessly coupled to a receiver-side coil of a power receiver, determining, at the power receiver, a real power transferred from the power transmitter, transmitting information associated with the determined real power to the power transmitter through the coupling between the receiver-side coil and the transmitter-side coil, and adjusting, at the power transmitter, the input power in response to determining, according to the transmitted information, that the real power differs from an expected power corresponding to the input power by over a first threshold, causing the real power to tune towards the expected power.

Abstract: A wireless power transfer system is disclosed. The wireless power transfer system may comprise a first group of transmitter coils disposed in a first plane, a second group of transmitter coils disposed in a second plane, and a controller unit configured to: supply a first power to the first group, one or more transmitter coils at a time; compare a first coupling strength of the powered first transmitter coil with a first threshold; in response to determining the first coupling strength exceeding the first threshold, determine the transmitter coil as a selected transmitter coil; supply a second power to the second group, one or more transmitter coils at a time; compare a second coupling strength of the powered second transmitter coil with a second threshold; and in response to determining the second coupling strength exceeding the second threshold, determine the transmitter coil as another selected transmitter coil.

Abstract: A system for wireless electrical charging is disclosed. The system may comprise a charging station and one or more electric devices. The charging station may comprise an input node configured to receive a power input, and a transmitter resonant circuit including a transmitter coupling coil configured to oscillate at a resonant frequency. The one or more electric devices may comprise a receiver resonant circuit including a receiver coupling coil wirelessly coupled to the transmitter coupling coil, and a DC voltage charger configured to charge one or more batteries in the electric device.

Abstract: A wireless charging system, including a power transmitter configured to generate wireless energy, and a power receiver configured to receive wireless energy at a predetermined carrier frequency that could be fixed or tuned during operation. A controller, wherein the controller is configured to activate when the power receiver receives the wireless energy. The controller may be configured to control a load modulation element to generate one or more signals containing relevant information for system operation and performance optimization, and wherein the one or more signals are transmitted via the power receiver.

Abstract: An integrated circuit for wireless power transfer is disclosed. The integrated circuit may comprise a boost controller configured to pump up a system input to a DC input, an oscillator configured to generate a frequency signal, a MOS (metal-oxide-semiconductor) driver coupled to the oscillator, and a power switch coupled to the MOS driver. The MOS driver may be configured to receive the frequency signal and drive the power switch to convert, based on the frequency signal, the DC input to an AC input to a resonant circuit connected to the integrated circuit.

Abstract: An apparatus for charging one or more electric devices. The device may comprise a resonant circuit configured to wirelessly couple to the one or more electric devices, a boost converter configured to convert a system voltage received by the apparatus to an input voltage of a power amplifier that drives the resonant circuit, a sensing circuit configured to detect the input voltage and an associated input current, and a controller. The controller may be configured to receive the detected input voltage and the detected input current, compare the received input voltage and the received input current with stored voltage and current information, identify a difference between the received input voltage and a predetermined voltage according to the stored voltage and current information, and control the boost converter to adjust the input voltage by the identified difference to the predetermined voltage. The adjustment may not need any feedback or communication from the power receiver unit.