Wireless power transfer system, power reception apparatus, and control method therefor

A power reception apparatus, comprising:

• an annular substrate and a coil that are stacked such that central axes of the substrate and the coil substantially coincide with each other;
• and
• a power reception circuit configured to rectify an electric current that is generated at the coil through at least one of electromagnetic induction or magnetic resonance, wherein the power reception circuit is implemented on the substrate,
• wherein
• the substrate is a multilayer substrate that includes a first layer provided with a ground pattern and a second layer provided with a power supply pattern, and
• the substrate includes a slit portion where the ground pattern and the power supply pattern are not present as viewed from a direction of the central axes.

A method for controlling a wireless power transfer system that includes an annular first substrate, a first coil, a second coil, and an annular second substrate that are stacked such that central axes of the first substrate, the first coil, the second coil, and the second substrate substantially coincide with each other, the method comprising:

• applying a voltage to the first coil from a power transmission circuit implemented on the first substrate;
• and
• rectifying an electric current that is generated at the second coil through at least one of electromagnetic induction or magnetic resonance, by a power reception circuit implemented on the second substrate,
• wherein
• the second substrate is a multilayer substrate that includes a first layer provided with a ground pattern and a second layer provided with a power supply pattern, and
• the second substrate includes a slit portion where the ground pattern and the power supply pattern are not present as viewed from a direction of the central axes.

A wireless power transfer system, comprising:

• an annular first substrate, a first coil, a second coil, and an annular second substrate that are stacked such that central axes of the first substrate, the first coil, the second coil, and the second substrate substantially coincide with each other;
• a power transmission circuit configured to apply a voltage to the first coil, wherein the power transmission circuit is implemented on the first substrate;
• and
• a power reception circuit configured to rectify an electric current that is generated at the second coil through at least one of electromagnetic induction or magnetic resonance, wherein the power reception circuit is implemented on the second substrate,
• wherein a pattern formed by a conductor on the second substrate is not a loop shape surrounding a center of the second substrate as viewed from a direction of the central axes, and
• wherein the second substrate is a multilayer substrate that includes a first layer provided with a ground pattern providing a reference potential to the second substrate and a second layer provided with a power supply pattern.

A method for controlling a wireless power transfer system that includes an annular first substrate, a first coil, a second coil, and an annular second substrate that are stacked such that central axes of the first substrate, the first coil, the second coil, and the second substrate substantially coincide with each other, the method comprising:

• applying a voltage to the first coil from a power transmission circuit implemented on the first substrate;
• and
• rectifying an electric current that is generated at the second coil through at least one of electromagnetic induction or magnetic resonance, by a power reception circuit implemented on the second substrate,
• wherein a pattern formed by a conductor on the second substrate is not a loop shape surrounding a center of the second substrate as viewed from a direction of the central axes, and
• wherein the second substrate is a multilayer substrate that includes a first layer provided with a ground pattern providing a reference potential to the second substrate and a second layer provided with a power supply pattern.