Charging pad and a method for charging one or more receiver devices
A charging pad for charging one or more receiver devices is disclosed. The charging pad includes a power drive unit configured to generate a first AC voltage signal having a first frequency and a second AC voltage signal having a second frequency. Further, the charging pad includes a transmitting unit including a single power exchange coil coupled to the power drive unit, wherein the single power exchange coil includes a first coil segment configured to transmit the first AC voltage signal having the first frequency when the first AC voltage signal is received from the power drive unit. Also, the single power exchange coil includes a second coil segment configured to transmit the second AC voltage signal having the second frequency when the second AC voltage signal is received from the power drive unit.
1. A charging pad comprising:
a power drive unit configured to generate a first AC voltage signal having a first frequency and a second AC voltage signal having a second frequency; and
a transmitting unit comprising a power exchange coil coupled to the power drive unit, wherein the power exchange coil comprises a plurality of coil segments,
wherein a first coil segment of the plurality of coil segments is selected to excite at the first frequency to transmit the first AC voltage signal having the first frequency in response to receiving the first AC voltage signal having the first frequency from the power drive unit, and
wherein a second coil segment of the plurality of coil segments is selected to excite at the second frequency to transmit the second AC voltage signal having the second frequency in response to receiving the second AC voltage signal having the second frequency from the power drive unit.
2. The charging pad of claim 1 , wherein the transmitting unit further comprises a first resonator comprising the first coil segment and a first capacitor coupled to the first coil segment, wherein the first resonator is configured to resonate at the first frequency to transmit the first AC voltage signal having the first frequency.
3. The charging pad of claim 2 , wherein the transmitting unit further comprises a second resonator comprising the second coil segment and a second capacitor coupled to the second coil segment, wherein the second resonator is configured to resonate at the second frequency to transmit the second AC voltage signal having the second frequency.
4. The charging pad of claim 1 , wherein the power exchange coil has a distributed inductance and a distributed capacitance, wherein the power exchange coil is configured to resonate at the first frequency to transmit the first AC voltage signal having the first frequency.
5. The charging pad of claim 1 , wherein the first coil segment is configured to inductively transmit the first AC voltage signal having the first frequency to a first receiver device.
6. The charging pad of claim 1 , wherein the second coil segment is configured to inductively transmit the second AC voltage signal having the second frequency to a second receiver device.
7. The charging pad of claim 1 , wherein the first coil segment and the second coil segment are interwound spirally to form a swiss roll structure.
8. The charging pad of claim 1 , wherein the power drive unit comprises at least one of a converting unit and an oscillating unit, configured to generate the first AC voltage signal having the first frequency and the second AC voltage signal having the second frequency.
9. The charging pad of claim 1 , wherein the first coil segment has an internal capacitance and an internal inductance, wherein the first coil segment is configured to excite at the first frequency to transmit the first AC voltage signal having the first frequency.
10. The charging pad of claim 1 , wherein the second coil segment comprises an internal capacitance and an internal inductance, wherein the second coil segment is configured to excite at the second frequency to transmit the second AC voltage signal having the second frequency.
11. A wireless charging device comprising:
a charging pad comprising:
a power drive unit configured to generate a first AC voltage signal having a first frequency and a second AC voltage signal having a second frequency; and
a transmitting unit comprising a power exchange coil coupled to the power drive unit, wherein the power exchange coil comprises a plurality of coil segments:
wherein a first coil segment of the plurality of coil segments is selected to excite at the first frequency to transmit the first AC voltage signal having the first frequency in response to receiving the first AC voltage signal having the first frequency from the power drive unit; and
wherein a second coil segment of the plurality of coil segments is selected to excite at the second frequency to transmit the second AC voltage signal having the second frequency in response to receiving the second AC voltage signal having the second frequency from the power drive unit; and
a control unit operatively coupled to the power drive unit and configured to control a voltage gain of the power drive unit.
12. The wireless charging device of claim 11 , wherein the control unit is further configured to send at least one of a first frequency control signal and a second frequency control signal to the power drive unit.
13. The wireless charging device of claim 12 , wherein the power drive unit comprises a converting unit configured to:
convert a DC voltage signal of an input power to the first AC voltage signal having the first frequency if the first frequency control signal is received from the control unit; and
convert the DC voltage signal of the input power to the second AC voltage signal having the second frequency if the second frequency control signal is received from the control unit.
14. The wireless charging device of claim 11 , wherein the power drive unit comprises an oscillating unit configured to generate the first AC voltage signal having the first frequency and the second AC voltage signal having the second frequency.
15. The wireless charging device of claim 11 , wherein the transmitting unit further comprises a first resonator comprising the first coil segment and a first capacitor coupled to the first coil segment, wherein the first resonator is configured to resonate at the first frequency to transmit the first AC voltage signal having the first frequency.
16. The wireless charging device of claim 15 , wherein the transmitting unit further comprises a second resonator comprising the second coil segment and a second capacitor coupled to the second coil segment, wherein the second resonator is configured to resonate at the second frequency to transmit the second AC voltage signal having the second frequency.
17. The wireless charging device of claim 11 , wherein the power exchange coil comprises a distributed inductance and a distributed capacitance, wherein the power exchange coil is configured to resonate at the first frequency to transmit the first AC voltage signal having the first frequency.
18. The wireless charging device of claim 11 , wherein the first coil segment is configured to inductively transmit the first AC voltage signal having the first frequency to a first receiver device.
19. The wireless charging device of claim 18 , wherein the second coil segment is configured to inductively transmit the second AC voltage signal having the second frequency to a second receiver device.
20. The wireless charging device of claim 11 , wherein the power drive unit comprises a drive coil magnetically coupled to the power exchange coil of the transmitting unit.