Abstract: A reception pad for a wireless power transfer (WPT) system includes: a plate-shaped ferrite; an insulating layer disposed on one side of the ferrite; a first coil layer disposed on the insulating layer; an interlayer insulating layer disposed on the first coil layer; and a second coil layer disposed on the interlayer insulating layer. The insulating layer at least partially surrounds the first coil layer and the second coil layer, the first coil layer and the second coil layer at least partially overlap each other and are arranged in a rectangular ring form on the one side of the ferrite, and a ratio of a width which is larger between a first width of the first coil layer and a second width of the second coil layer to a first length of the ferrite in a width direction corresponding to the first width or the second width is 0.14 to 0.15.

Abstract: A wireless power transmission pad for transmitting wireless power to a reception pad including a secondary coil includes: a rectangular-shaped primary coil having an X-width defined in an x-direction and a Y-width defined in a y-direction and having a central space; a ferrite coupled to the primary coil; and a housing supporting the primary coil and the ferrite. A first cross-sectional area of a first portion including the X-width of the primary coil is smaller than a second cross-sectional area of a second portion including the Y-width of the primary coil.

Abstract: A primary coil circuit of a ground assembly for wirelessly transferring power to a secondary coil includes: a primary coil magnetically coupled to the secondary coil and having a first terminal and a second terminal; a second capacitor having a first terminal and a second terminal connected to the first terminal of the primary coil; a first inductor having a first terminal coupled to a first input terminal of a power source and a second terminal coupled to the first terminal of the second capacitor; and a first capacitor having a first terminal coupled commonly to the second terminal of the first inductor and the first terminal of the second capacitor and a second terminal coupled commonly to the second terminal of the primary coil and a second input terminal of the power source.

Abstract: A reception pad for a wireless power transfer (WPT) system includes: a plate-shaped ferrite; an insulating layer disposed on one side of the ferrite; a first coil layer disposed on the insulating layer; an interlayer insulating layer disposed on the first coil layer; and a second coil layer disposed on the interlayer insulating layer. The insulating layer at least partially surrounds the first coil layer and the second coil layer, the first coil layer and the second coil layer at least partially overlap each other and are arranged in a rectangular ring form on the one side of the ferrite, and a ratio of a width which is larger between a first width of the first coil layer and a second width of the second coil layer to a first length of the ferrite in a width direction corresponding to the first width or the second width is 0.14 to 0.15.

Abstract: A primary coil circuit of a ground assembly for wirelessly transferring power to a secondary coil includes: a primary coil magnetically coupled to the secondary coil and having a first terminal and a second terminal; a second capacitor having a first terminal and a second terminal connected to the first terminal of the primary coil; a first inductor having a first terminal coupled to a first input terminal of a power source and a second terminal coupled to the first terminal of the second capacitor; and a first capacitor having a first terminal coupled commonly to the second terminal of the first inductor and the first terminal of the second capacitor and a second terminal coupled commonly to the second terminal of the primary coil and a second input terminal of the power source.

Abstract: A wireless power transmission pad for transmitting wireless power to a reception pad including a secondary coil includes: a rectangular-shaped primary coil having an X-width defined in an x-direction and a Y-width defined in a y-direction and having a central space; a ferrite coupled to the primary coil; and a housing supporting the primary coil and the ferrite. A first cross-sectional area of a first portion including the X-width of the primary coil is smaller than a second cross-sectional area of a second portion including the Y-width of the primary coil.