Wireless power transmission device for vehicle and wireless charging method

1 . A method of a wireless power transmission device for a vehicle, the method comprising:

transmitting a wireless power signal from the wireless power transmission device to a wireless power reception device, the wireless power signal having a power signal frequency in a transmitter frequency band that is lower than a transmitter resonance frequency of the wireless power transmission device, wherein the transmitter frequency band is different from an operation frequency band of a control system of the vehicle, wherein the transmitter resonance frequency is different from a receiver resonance frequency of the wireless power reception device, and wherein the transmitter resonance frequency is higher than the receiver resonance frequency;

receiving a power control signal from the wireless power reception device; and

controlling the power signal frequency based on the power control signal and the transmitter frequency band, wherein the controlling includes:

adjusting the power signal frequency to a lower frequency when the power control signal indicates a request for a decrease in power and the power signal frequency is lower than the receiver resonance frequency; and

adjusting the power signal frequency to a higher frequency when the power control signal indicates a request for an increase in power and the power signal frequency is lower than the receiver resonance frequency.

2 . The method of claim 1 , wherein the operation frequency band of the control system of the vehicle includes an operation frequency of a smart key.

3 . The method of claim 1 , further comprising:

transmitting, from the wireless power transmission device, a detecting signal for detecting the wireless power reception device; and

receiving a response signal from the wireless power reception device in response to the detecting signal.

4 . The method of claim 3 , wherein transmitting the detecting signal for detecting the wireless power reception device comprises transmitting the detecting signal at a frequency outside of the operation frequency band of the control system of the vehicle.

5 . The method of claim 1 , wherein the controlling the power signal frequency includes adjusting the power signal frequency based on the power control signal and a left frequency band.

6 . The method of claim 1 , further comprising:

adjusting the power signal frequency to a lower frequency when the power control signal indicates a request for the increase in power and the power signal frequency is higher than the receiver resonance frequency; and

adjusting the power signal frequency to a higher frequency when the power control signal indicates a request for the decrease in power and the power signal frequency is higher than the receiver resonance frequency.

7 . The method of claim 1 , further comprising:

controlling the power signal frequency based on a transmitter frequency resonance curve associated with the transmitter resonance frequency, wherein the transmitter frequency resonance curve is different from a receiver frequency resonance curve associated with the receiver resonance frequency.

8 . The method of claim 1 , further comprising:

adjusting a voltage of the wireless power signal in coordination with adjusting the power signal frequency based on the power control signal.

9 . A vehicle comprising:

a control system that uses an operation frequency band; and

a wireless power transmission device configured to:

transmit a wireless power signal to a wireless power reception device, the wireless power signal having a power signal frequency in a transmitter frequency band that is lower than a transmitter resonance frequency of the wireless power transmission device, wherein the transmitter frequency band is different from the operation frequency band of the control system, wherein the transmitter resonance frequency is different from a receiver resonance frequency of the wireless power reception device, and wherein the transmitter resonance frequency is higher than the receiver resonance frequency,

receive a power control signal from the wireless power reception device, and

control the power signal frequency based on the power control signal and the transmitter frequency band, wherein the wireless power transmission device is configured to:

adjust the power signal frequency to a lower frequency when the power control signal indicates a request for a decrease in power and the power signal frequency is lower than the receiver resonance frequency; and

adjust the power signal frequency to a higher frequency when the power control signal indicates a request for an increase in the power and the power signal frequency is lower than the receiver resonance frequency.

10 . The vehicle of claim 9 , wherein the the control system of the vehicle includes a smart key.

11 . The vehicle of claim 9 , wherein the wireless power transmission device includes:

a primary coil to transmit the wireless power signal to the wireless power reception device; and

a control unit configured to set the power signal frequency.

12 . The vehicle of claim 11 , wherein the control unit is configured to:

transmit, from the wireless power transmission device, a detecting signal for detecting the wireless power reception device; and

receive a response signal from the wireless power reception device in response to the detecting signal.

13 . The vehicle of claim 9 , wherein:

the transmitter frequency band is above 90 kilohertz (KHz), and

the operation frequency band of the control system includes a 125 KHz operation frequency.

14 . The vehicle of claim 9 , wherein:

the receiver resonance frequency (Fo) is 100 KHz,

the transmitter resonance frequency (F′o) is higher than the receiver resonance frequency (FO), and

the transmitter frequency band is less than the transmitter resonance frequency (F′o).

15 . The vehicle of claim 9 , wherein the transmitter resonance frequency is different from the receiver resonance frequency, and wherein the transmitter resonance frequency is higher than the receiver resonance frequency.

16 . The vehicle of claim 9 , wherein the wireless power transmission device is further configured to:

adjust the power signal frequency to a lower frequency when the power control signal indicates a request for the increase in power and the power signal frequency is higher than the receiver resonance frequency; and

adjust the power signal frequency to a higher frequency when the power control signal indicates a request for the decrease in power and the power signal frequency is higher than the receiver resonance frequency.

17 . A wireless power transmission apparatus, comprising:

an electric driving unit to supply driving signals;

a primary coil to generate an electromagnetic field based on the driving signals, the electromagnetic field operable to transmit a wireless power signal to a wireless power reception apparatus, the wireless power signal having a power signal frequency in a transmitter frequency band that is lower than a transmitter resonance frequency of the wireless power transmission apparatus, wherein the transmitter frequency band is different from an operation frequency band of a control system of a vehicle, wherein the transmitter resonance frequency is different from a receiver resonance frequency of the wireless power reception apparatus, and where in the transmitter resonance frequency is higher than the receiver resonance frequency; and

a control unit configured to:

receive a power control signal from the wireless power reception apparatus, and

control the power signal frequency of the wireless power signal based on a frequency of the driving signals supplied by the electric driving unit and the transmitter frequency band

adjust the frequency of the driving signals such that the power signal frequency is decreased when the power control signal indicates a request for a decrease in power and the power signal frequency is lower than the receiver resonance frequency; and

adjust the frequency of the driving signals such that the power signal frequency is increased when the power control signal indicates a request for an increase in the power and the power signal frequency is lower than the receiver resonance frequency.

18 . The wireless power transmission apparatus of claim 17 , further comprising a current measuring unit to measure current flowing in the primary coil.

19 . The wireless power transmission apparatus of claim 18 , wherein the control unit is configured to:

adjust the frequency of the driving signals to a higher frequency or a lower frequency based on the power control signal received from the wireless power reception apparatus and the measured current flowing in the primary coil.