WIRELESS POWER TRANSMISSION METHOD AND APPARATUS FOR IMPROVING SPECTRUM EFFICIENCY AND SPACE EFFICIENCY BASED ON IMPEDANCE MATCHING AND RELAY RESONANCE

• US 20150108850A1
• Filed: 09/11/2014
• Published: 04/23/2015
• Est. Priority Date: 10/21/2013
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: CHO, In Kui, KIM, Seong Min, MOON, Jung Ick, YUN, Je Hoon
• Granted Patent: US 10,038,340 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/50 using additional energy repeaters between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment

Abstract

Provided is a wireless power transmission method and apparatus for improving spectrum efficiency and space efficiency based on impedance matching and relay resonance, the method including detecting an input impedance at a resonant frequency, matching a transmitting port impedance to a real number value of the detected input impedance, and transmitting power to a receiving resonator smaller than a transmitting resonator using the relay resonator.

Claims

1. A wireless power transmitting apparatus, the apparatus comprising:

an input impedance detector to detect an input impedance of a transmitting resonator connected to the wireless power transmitting apparatus at a resonant frequency;

a control signal output unit to output a control signal to control a transmitting port impedance based on the input impedance;

a transmitting port impedance converter to convert the transmitting port impedance based on the control signal; and

a power transmitter to transmit power to a wireless power receiving apparatus through the transmitting resonator at the resonant frequency based on the converted transmitting port impedance,

wherein the input impedance is adjusted based on a distance between the transmitting resonator and a receiving resonator connected to the wireless power receiving apparatus.

2. The apparatus of claim 1, wherein the transmitting port impedance converter converts the transmitting port impedance to match a real number value of the input impedance based on the control signal.

3. The apparatus of claim 1, wherein the transmitting port impedance converter converts the transmitting port impedance by controlling a distance between the transmitting resonator and a feeding coil used to provide power to the transmitting resonator.

4. The apparatus of claim 1, wherein the control signal output unit outputs the control signal based on an amount of power consumed in the wireless power receiving apparatus and a radio frequency/direct current (RF/DC) conversion efficiency of the wireless power receiving apparatus.

5. A wireless power receiving apparatus, the apparatus comprising:

a power receiver to receive power from a transmitting resonator connected to a wireless power transmitting apparatus at a resonant frequency; and

a load unit consuming the received power,

wherein the wireless power transmitting apparatus converts a transmitting port impedance based on an input impedance of the transmitting resonator detected at the resonant frequency and transmits power through the transmitting resonator.

6. The apparatus of claim 5, wherein the wireless power transmitting apparatus converts the transmitting port impedance to match a real number value of the input impedance.

7. The apparatus of claim 5, wherein the wireless power transmitting apparatus converts the transmitting port impedance by controlling a distance between the transmitting resonator and a feeding coil used to provide power to the transmitting resonator.

8. The apparatus of claim 5, wherein the input impedance is adjusted based on a distance between the transmitting resonator and a receiving resonator connected to the wireless power receiving apparatus.

9. A wireless power transfer apparatus, the apparatus comprising:

a transmitting resonator to transmit power generated from a wireless power transmitting apparatus to a receiving resonator at a resonant frequency; and

a receiving resonator to receive the power from the transmitting resonator using a relay resonator, wherein a size of the receiving resonator is smaller than a size of the transmitting resonator, and

wherein the relay resonator controls a receiving efficiency of the receiving resonator by adjusting a distance from the receiving resonator.

10. The apparatus of claim 9, wherein the wireless power transmitting apparatus converts a transmitting port impedance based on an input impedance of the transmitting resonator detected at the resonant frequency and generates power.

11. The apparatus of claim 10, wherein the wireless power transmitting apparatus converts the transmitting port impedance to match a real number value of the input impedance.

12. The apparatus of claim 10, wherein the wireless power transmitting apparatus converts the transmitting port impedance by controlling a distance between the transmitting resonator and a feeding coil used to provide power to the transmitting resonator.

13. The apparatus of claim 10, wherein the input impedance is adjusted based on a distance between the transmitting resonator and the receiving resonator connected to a wireless power receiving apparatus.

14. The apparatus of claim 9, wherein a size of the relay resonator is identical to a size of the transmitting resonator.

15. A wireless power transmitting method, the method comprising:

detecting an input impedance of a transmitting resonator connected to a wireless power transmitting apparatus at a resonant frequency;

outputting a control signal to adjust a transmitting port impedance based on the input impedance;

converting the transmitting port impedance based on the control signal; and

transmitting power to a wireless power receiving apparatus through the transmitting resonator at the resonant frequency based on the converted transmitting port impedance,

wherein the input impedance is adjusted based on a distance between the transmitting resonator and a receiving resonator connected to the wireless power receiving apparatus.

16. The method of claim 15, wherein the converting is performed to match the transmitting port impedance to a real number value of the input impedance based on the control signal.

17. The method of claim 15, wherein the converting is performed by controlling a distance between the transmitting resonator and a feeding coil used to provide power to the transmitting resonator.