Electronic device for transmitting wireless power having a plurality of power transmission coils and operating method therefor to identify position of a wireless power reception device
A wireless power transmission device includes power transmission coils for transmitting power to a wireless power reception device; inverters for applying alternating current power to the coils; a communication module using a frequency different from that of the power transmitted from the coils; and a processor. The processor controls the inverters such that first power is sequentially applied to the coils respectively, receives a communication signal from the reception device through the communication module while the first power is being sequentially applied, identifies a first coil corresponding to a position of the reception device based on of a reception time point of the communication signal and time points at which the first power starts to be applied to the coils, and controls a first inverter corresponding to the first coil such that second power for charging the reception device is applied to the first coil.
1. A wireless power transmission device comprising:
a plurality of power transmission coils configured to transmit power to a wireless power reception device, the plurality of power transmission coils comprising a first power transmission coil and a second power transmission coil;
a plurality of inverters configured to respectively apply alternating current power to a corresponding one of the plurality of power transmission coils, the plurality of inverters comprising a first inverter and a second inverter;
at least one communication module using a frequency different from that of the power transmitted from the plurality of power transmission coils;
at least one processor; and
a memory storing instructions,
wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to:
control the plurality of inverters to thereby sequentially apply first power to the plurality of power transmission coils, including controlling the first inverter to apply the first power to the first power transmission coil for a first predetermined duration starting from a first time point, and controlling the second inverter to apply the first power to the second power transmission coil for a second predetermined duration starting from a second time point, wherein the second time point is subsequent to the first time point and is during the first predetermined duration,
receive a first communication signal from the wireless power reception device through the at least one communication module while the first power is sequentially applied to the plurality of power transmission coils,
identify a corresponding power transmission coil, of the plurality of power transmission coils, as corresponding to a position of the wireless power reception device, based on a reception time point of the first communication signal relative to at least one time point at which the first power starts to be applied to the corresponding power transmission coil, and
control a corresponding inverter, of the plurality of inverters, corresponding to the identified corresponding power transmission coil to apply second power for charging the wireless power reception device to the identified corresponding power transmission coil.
2. The wireless power transmission device of claim 1 , wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to control the plurality of inverters using a clock signal identified based on power input to the plurality of inverters.
3. The wireless power transmission device of claim 1 , further comprising an oscillator,
wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to control the plurality of inverters using a clock signal generated by the oscillator.
4. The wireless power transmission device of claim 1 ,
wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to identify the corresponding power transmission coil based on the reception time point of the first communication signal from the wireless power reception device being between the first time point and the second time point.
5. The wireless power transmission device of claim 1 , wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to identify the corresponding power transmission coil based on determining that a time interval between the first time point and the reception time point of the first communication signal is smaller than a predetermined reference value.
6. The wireless power transmission device of claim 1 ,
wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to, based on receipt of the first communication signal after the first time point and within the predetermined duration starting from the second time point, to respectively control the plurality of inverters to sequentially and periodically re-apply the first power to the plurality of power transmission coils.
7. The wireless power transmission device of claim 1 , further comprising a power sensor connected to the plurality of power transmission coils,
wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to:
identify a first impedance change with respect to the first power transmission coil, based on a result measured by the power sensor while the first power is applied to the first power transmission coil,
identify a second impedance change with respect to the second power transmission coil, based on a result measured by the power sensor while the first power is applied to the second power transmission coil, and
identify the corresponding power transmission coil based on the reception time point of the first communication signal, the first time point, the second time point, the first impedance change, and the second impedance change.
8. The wireless power transmission device of claim 1 , further comprising a power sensor connected to the plurality of power transmission coils,
wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to:
control the at least one communication module to transmit a load change command to the wireless power reception device after identifying the corresponding power transmission coil,
identify an impedance change with respect to the corresponding power transmission coil based on a result measured by the power sensor after transmitting the load change command, and
identify whether the impedance change corresponds to a pattern of the load change command.
9. The wireless power transmission device of claim 1 , further comprising a power sensor connected to the plurality of power transmission coils,
wherein the instructions, when executed by at least one processor individually or collectively, cause the wireless power transmission device to:
identify an impedance change with respect to a second corresponding power transmission coil, of the plurality of power transmission coils, based on a result measured by the power sensor, and
control a second corresponding inverter, of the plurality of inverters, corresponding to the identified second corresponding power transmission coil to apply third power for heating an external device to the second corresponding power transmission coil, based on the identified impedance change.
10. An operation method of a wireless power transmission device, the operation method comprising:
controlling a plurality of inverters of the wireless power transmission device, each of the plurality of inverters corresponding to one of a plurality of power transmission coils of the wireless power transmission device respectively, to thereby sequentially apply first power to the plurality of power transmission coils of the wireless power transmission device, wherein the controlling the plurality of inverters comprises controlling a first inverter, among the plurality of inverters, to apply the first power to a first power transmission coil, among the plurality of power transmission coils, for a first predetermined duration starting from a first time point, and controlling a second inverter, among the plurality of inverters, to apply the first power to a second power transmission coil, among the plurality of power transmission coils, for a second predetermined duration starting from a second time point, wherein the second time point is subsequent to the first time point and is during the first predetermined duration;
receiving a communication signal from a wireless power reception device through at least one communication module of the wireless power transmission device while the first power is sequentially applied to the plurality of power transmission coils;
identifying a corresponding power transmission coil, of the plurality of power transmission coils, as corresponding to a position of the wireless power reception device, based on a reception time point of the first communication signal relative to at least one time point at which the first power starts to be applied to the corresponding power transmission coil; and
controlling a corresponding inverter, of the plurality of inverters, corresponding to the identified corresponding power transmission coil, to apply second power for charging the wireless power reception device to the corresponding power transmission coil.
11. The operation method of claim 10 , wherein the controlling the plurality of inverters comprises using a clock signal identified based on power input to the plurality of inverters.
12. The operation method of claim 10 , wherein the controlling the plurality of inverters comprises using a clock signal generated by an oscillator of the wireless power transmission device.
13. The operation method of claim 10 ,
wherein the identifying the corresponding power transmission coil is based on the reception time point of the first communication signal from the wireless power reception device being between the first time point and the second time point.