WIRELESS POWER TRANSFER DEVICE
The present invention relates to a wireless power transmission apparatus, which comprises a first transmission coil configured to operate in a first resonance frequency band; and a second transmission coil configured to operate in a second resonance frequency band, the first and second transmission coils being arranged in the same plane. According to the present invention, a wireless power transmission apparatus may transmit power efficiently.
1 . A wireless power transmission apparatus, comprising:
a first transmission coil configured to operate in a first resonance frequency band; and
a second transmission coil configured to operate in a second resonance frequency band, the first and second transmission coils being arranged in the same plane,
wherein the second transmission coil includes a number of wires, and
wherein the distance between the wires is determined correspondingly to the first resonance frequency band.
2 . The wireless power transmission apparatus of claim 1 , wherein the second transmission coil generates a parasitic capacitance correspondingly to the first resonance frequency band, blocking the power transmitted from the first transmission coil so that the power does not flow into the second transmission coil.
3 . The wireless power transmission apparatus of claim 1 , wherein the size of the wires is determined correspondingly to the first resonance frequency band.
4 . The wireless power transmission apparatus of claim 1 , wherein the second transmission coil includes a number of unit coils, and
wherein the distance between the unit coils is determined correspondingly to the first resonance frequency band.
5 . The wireless power transmission apparatus of claim 4 , wherein the size of the unit coils is determined correspondingly to the first resonance frequency band.
6 . The wireless power transmission apparatus of claim 1 , wherein the second transmission coil performs a parallel resonance in the first resonance frequency band, and a series resonance in the second resonance frequency band.
7 . The wireless power transmission apparatus of claim 1 , wherein the wires are sequentially arranged from the outside to the inside.
8 . The wireless power transmission apparatus of claim 4 , wherein any one of the unit coils is layered between the other two unit coils.
9 . The wireless power transmission apparatus of claim 1 , wherein the first transmission coil surrounds the second transmission coil.
10 . The wireless power transmission apparatus of claim 1 , wherein the first transmission coil is formed in a resonance scheme.
11 . The wireless power transmission apparatus of claim 1 , wherein the second transmission coil is formed in an electromagnetic induction method.
12 . The wireless power transmission apparatus of claim 1 , wherein the value of the parasitic capacitance increases as the distance between the wires decreases.
13 . The wireless power transmission apparatus of claim 1 , wherein the value of the parasitic capacitance increases as the length of the wires increases.
14 . The wireless power transmission apparatus of claim 1 , wherein the value of the parasitic capacitance increases as the turn number of the wires increases.
15 . The wireless power transmission apparatus of claim 1 , wherein the value of the parasitic capacitance increases as the thickness of the wires increases.
16 . The wireless power transmission apparatus of claim 1 , wherein the first resonance frequency is 6.78 MHz, and
wherein the second resonance frequency is 100 kHz.
17 . A wireless power transmission apparatus, comprising:
a first transmission coil configured to operate in a first resonance frequency band; and
a second transmission coil configured to operate in a second resonance frequency band,
wherein in case that the first transmission coil operates in the first resonance frequency band, the second transmission coil generates a parasitic capacitance, to block the power generated by a magnetic flux coupling between the first and second transmission coils not to be flown into the second transmission coil.
18 . The wireless power transmission apparatus of claim 17 , wherein the first transmission coil includes a transmission induction coil and a transmission resonance coil, and
wherein the second transmission coil includes a transmission induction coil.
19 . The wireless power transmission apparatus of claim 17 , wherein the second transmission coil has wires in that the distance between the wires and the size of the wires are arranged such that the second transmission coil generates a parasitic capacitance correspondingly to the first resonance frequency band.
20 . The wireless power transmission apparatus of claim 17 , wherein the second transmission coil performs a parallel resonance in the first resonance frequency band, and a series resonance in the second resonance frequency band.