WO2012091207A1

WO2012091207A1 - Multi-node wireless power transmission system using magnetic resonance induction and method for charging same

Info

Publication number: WO2012091207A1
Application number: PCT/KR2011/000527
Authority: WO
Inventors: 황규성; 임승옥; 원윤재; 김선희; 문연국
Original assignee: 전자부품연구원
Priority date: 2010-12-30
Filing date: 2011-01-26
Publication date: 2012-07-05
Also published as: KR101171938B1; KR20120077449A

Abstract

The present invention relates to a multi-node wireless power transmission system using magnetic resonance induction, which can efficiently charge multiple wireless charging devices, and to a method for charging same, which efficiently charges the entire multi-node wireless power transmission system by a step of a wireless power transmission/reception device identifying the distance to each of the wireless charging devices from the wireless power transmission/reception device by means of magnetic field communication, and a step of controlling a portion of the wireless charging devices so as to use same as repeaters or block the power reception function of a portion of the wireless charging devices.

Description

Multi-node wireless power transfer system using magnetic resonance induction method and charging method thereof

The present invention relates to a wireless power transmission system, and more particularly, to a multi-node wireless power transmission system using a magnetic resonance induction method that can efficiently charge a plurality of wireless chargers and a charging method thereof.

As a wireless power transmission technology for wirelessly transmitting energy, a wireless charging system using magnetic induction is used.

For example, electric toothbrushes or wireless shavers are charged with the principle of electromagnetic induction. Recently, wireless charging products for charging mobile devices such as mobile phones, PDAs, MP3 players, and notebook computers using electromagnetic induction have been introduced. .

However, the magnetic induction method of inducing current through a magnetic field from one coil to another is very sensitive to the distance and relative position between the coils, so that the transmission efficiency drops rapidly even if the distance between the two coils is slightly dropped or twisted. Accordingly, this magnetic induction charging system can only be used in a short distance of several cm or less.

On the other hand, US Patent 7,741,735 discloses a non-radiative energy transfer method based on the attenuation wave coupling of the resonant field. This is because two resonators with the same frequency do not affect other non-resonators around them, but they tend to couple with each other and are introduced as a technology that can transfer energy over a long distance compared to conventional electromagnetic induction. .

In a system in which energy is wirelessly transmitted using resonance, when there are a plurality of receivers, power is transmitted to all receiver apparatuses in which resonance occurs. In addition, the energy can be delivered to a far distance compared to the existing electromagnetic induction, but there is still a limit of the distance, there is a problem that the charging efficiency is sharply reduced when the distance is far.

SUMMARY OF THE INVENTION The present invention has been made in the technical background as described above, and an object thereof is to provide a multi-node wireless power transmission system and a charging method thereof, which are capable of charging a plurality of wireless chargers efficiently.

Another object of the present invention is to provide a system capable of charging other wireless chargers and a charging method thereof by utilizing some wireless chargers as repeaters in a multi-node wireless power transfer system.

In order to solve the above problems, in the present invention, after determining the distance from the wireless power transmitter to each wireless charger through magnetic field communication, the wireless charger may be controlled to be used as a repeater or the power reception function of some wireless chargers may be used. Blocking achieves efficient charging of the entire multinode wireless power transfer system.

According to an aspect of the present invention, there is provided a multi-node wireless power transmission system including a wireless power transmitter and a plurality of wireless chargers spaced apart from the wireless power transmitter, wherein the wireless power transmitter includes: The wireless charger is assigned one of charging, repeater, and off states based on the distance between the wireless power transmitter and the wireless charger and whether the wireless charger needs to be charged. An internal circuit is controlled to receive a wireless power transmitted from the wireless power transmitter in a magnetic resonance induction method by matching a resonance frequency with the wireless power transmitter in the charged state, and to transmit the wireless power in the repeater state. Match the device and the resonance frequency to the wireless power transmitter If the emitter naemyeo bounced back the wireless power transmission, the OFF state is characterized in that to avoid self-resonance and the wireless power transmission apparatus.

The wireless charger includes a receiving antenna for receiving wireless power transmitted from the wireless power transmitter and a matching circuit for matching a resonant frequency between the wireless power transmitter and the wireless charger. And a matching network including a power control capacitor connected in parallel with the matching circuit, a matching switch having one end connected with the matching circuit and the other end connected with the power control capacitor, and connected with the matching network. It may include a rectifier for rectifying the power supplied through the receiving antenna, a power control switch connected to the rear end of the rectifier, and a DC-DC converter, one end of which is connected to the power control switch and the other end of which is connected to a load.

In this case, the wireless charger, in the state of charge, the matching switch is turned off and the power control switch is turned on, and in the repeater state, the matching switch is turned off and the power control switch is turned off, If the matching switch is turned on.

Here, the power control capacitor preferably has a capacity of 2 to 10 times the capacitance of the matching circuit, the wireless power transmitter and the wireless charger may each include a magnetic field communication modem, the wireless power The transmitting device receives one or more pieces of identification information, type, location, and charging state of the wireless charger from the wireless charger.

The wireless power transmitter may include the first wireless charger between the first wireless charger that needs to be charged among the wireless chargers and the second wireless charger that does not require charging between the wireless power transmitters. Assigning the charging state to the second wireless charger, and assigning the repeater state to the second wireless charger, wherein the first wireless charger that needs to be charged among the wireless chargers, and the first wireless charger than the first wireless charger, When there is a third wireless charger located far between the wireless power transmitters and which does not require charging, the charging state may be allocated to the first wireless charger and the off state may be allocated to the second wireless charger. .

A charging method of a multi-node wireless power transmission system according to another aspect of the present invention includes a wireless power transmitter in a multi-node wireless power transmission system including a wireless power transmitter and a plurality of wireless chargers spaced apart from the wireless power transmitter. A charging method comprising: (a) the wireless charger charging, repeater, charging the wireless charger based on a distance between the wireless power transmitter and the wireless charger from the wireless power transmitter and whether the wireless charger needs to be charged; (B) when the wireless charger is assigned the charging state, matching the resonant frequency with the wireless power transmitter and performing magnetic resonance induction to the wireless power transmitted from the wireless power transmitter. To control the internal circuitry of the wireless charger to receive And (c) internal circuitry of the wireless charger to match the resonant frequency with the wireless power transmitter when the wireless charger is assigned the repeater state but to bounce the wireless power transmitted from the wireless power transmitter. And controlling (d) controlling an internal circuit of the wireless charger so as not to self-resonate with the wireless power transmitter when the wireless charger is assigned the OFF state.

According to the present invention, in the multi-node wireless power transmission system using the magnetic resonance induction method, a plurality of wireless chargers are set to one of charging / repeater / OFF based on whether the charging is necessary and the distance from the wireless power supply device. As a result, the wireless charger can be selectively charged, thereby efficiently charging multiple wireless chargers.

1 is a block diagram schematically showing the overall configuration of a multi-node wireless energy transmission system using a magnetic resonance induction method according to an embodiment of the present invention.

2 is a block diagram showing the configuration of a wireless power supply device and a wireless charger of a multi-node wireless energy transfer system using a magnetic resonance induction method according to an embodiment of the present invention.

3 is a flowchart illustrating a charging method of a multi-node wireless energy transmission system using a magnetic resonance induction method according to an embodiment of the present invention.

4 is a block diagram showing the configuration of a power management unit of a wireless charger according to an embodiment of the present invention.

5 is a conceptual diagram illustrating a situation in which efficient charging is performed by using a repeater in a multi-node wireless energy transmission system using a magnetic resonance induction method according to an embodiment of the present invention.

6 is a conceptual diagram illustrating a situation in which a wireless charger that does not require charging in a multi-node wireless energy transmission system using a magnetic resonance induction method according to an embodiment of the present invention performs efficient charging of the entire system by not disturbing the charging. to be.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the art to which the present invention pertains. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. Meanwhile, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, “comprises” and / or “comprising” refers to the presence of one or more other components, steps, operations and / or elements. Or does not exclude additions.

Hereinafter, a multi-node wireless energy transmission system using a magnetic resonance induction method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, a multi-node wireless energy transmission system using a magnetic resonance induction method according to an embodiment of the present invention includes a wireless power supply device 100 that wirelessly supplies power through a magnetic resonance induction method, and wireless power. Located a distance away from the supply device 100 by a predetermined distance and comprises a plurality of wireless chargers (200_1, 200_2, ..., 200_N) that is wirelessly supplied power from the wireless power supply (100). The plurality of wireless chargers 200_1, 200_2,..., 200_N are spaced apart from the wireless power supply 100 by a distance of d1, d2,..., DN, respectively.

Magnetic resonance induction is a method of maximizing the wireless transmission efficiency of energy by the resonance between the transmitting antenna and the receiving antenna. To this end, a resonance channel is formed by matching a resonance frequency between the wireless power supply device 100 and the wireless charger 200 to transmit wireless power.

The wireless power supply device 100 includes a wireless charger 200_1, 200_2, including identification information, type, location, or state of charge of the charger through magnetic field communication with the wireless charger 200_1, 200_2, .., 200_N. ..., 200_N) may be received, and power may be transmitted to the wireless chargers 200_1, 200_2,..., 200_N based on the charging information. In particular, in the embodiment of the present invention, the wireless power supply device 100 is the distance d1 to the wireless charger (200_1, 200_2, .., 200_N) through the magnetic field communication with the wireless charger (200_1, 200_2, ..., 200_N) Obtain information about, d2, ..., dN.

The wireless power supply device 100 may be implemented as a fixed type or a mobile type. When the wireless power supply device 100 is implemented as a fixed type, the wireless power supply device 100 may be installed in a furniture such as a ceiling or a table indoors. In addition, the wireless power supply device 100 may be installed inside a moving object such as a vehicle, a train, a subway. When the wireless power supply 100 is implemented as a mobile, the wireless power supply 100 itself may be implemented as a separate mobile device, or may be implemented as part of another digital device such as a cover of a notebook computer. .

The wireless chargers 200_1, 200_2, .., 200_N may include all digital devices including batteries such as various mobile terminals, digital cameras, and notebook computers, and are not easily accessible from underground, underwater, and inside buildings. It may also be an electronic device such as a sensor and a measuring instrument.

As shown in FIG. 2, the wireless power supply device 100 of the multi-node wireless energy transmission system using the magnetic resonance induction method according to an embodiment of the present invention receives a power supply from an external power supply source and uses the wireless power supply device ( The power converter 120 converts AC power having a resonant frequency band between the wireless charger 200 and the magnetic charger. The magnetic field communication modem performs magnetic field communication with the wireless charger 200 using a magnetic field communication protocol. 130, a transmission antenna 110 for transmitting AC power from the power converter 140 and data from the magnetic field communication modem 120 to the wireless charger 200 using a magnetic resonance induction method, and a power converter ( And a controller 130 that controls the components of the wireless power supply 100, including the 140 and magnetic field communication modem 120.

The wireless charger 200 of the multi-node wireless energy transfer system using the magnetic resonance induction method according to an embodiment of the present invention receives the power and data from the wireless power supply device 100 using the magnetic resonance induction method. The antenna 210, the magnetic field communication modem 230 to perform magnetic field communication with the wireless power supply device 100 using the magnetic field communication protocol, the power management unit 220 for managing power reception, the power management unit and the magnetic field communication modem ( The controller 240 controls the components of the wireless charger 200, including 230, and a battery 250 that is charged using the received power.

3 is a flowchart of a method for efficiently charging each wireless charger in a multi-node wireless energy transfer system using a magnetic resonance induction method according to an embodiment of the present invention.

As shown in FIG. 3, first, the wireless power supply device 100 receives identification information of the charger from each of the wireless chargers 200_1, 200_2,..., 200_N through magnetic field communication (S310). Next, at this time, in addition to the identification information of the charger may be further received information such as the type, location, or state of charge of the charger.

Next, the wireless power supply device 100 determines the distance from each of the wireless chargers 200_1, 200_2,..., 200_N using the received information (S320).

If the distance is determined, a charge / repeater / off command is transmitted to each of the wireless chargers 200_1, 200_2,..., 200_N (S330). Which command to transmit to the wireless chargers 200_1, 200_2,..., 200_N may be determined in various ways, which will be described later. In this case, other information other than the distance from each of the wireless chargers 200_1, 200_2,..., 200_N may be considered together.

According to the received charge / repeater / off command, each of the wireless chargers 200_1, 200_2,..., 200_N switches to a state according to the command, and the selective charging is performed as the wireless power supply 100 transmits power. It is made (S340). The state switching of the wireless charger according to each command will be described later.

In order to charge each wireless charger efficiently in a multi-node wireless energy transfer system using a magnetic resonance induction method, in the embodiment of the present invention, the wireless charger is charged / repeater / off state by controlling a circuit of a receiver (wireless charger). To work.

Referring to FIG. 4, the power management unit 220 includes an adaptive matching network 225, a rectifier 222, a power control switch 223, and a DC-DC converter 224. The DC-DC converter 224 is connected to a load (FIG. 2: 250), that is, a battery, etc. outside the power manager 220_1, and the power control switch 223 is connected to the controller (FIG. 2: 240) to control the controller (FIG. 2). : It operates by receiving ON / OFF switching signal from 240).

The frequency between the wireless power supply device 100 and the wireless charger 200 is resonant, and between the receiving antenna 210 and the rectifier 222 to perform impedance matching between the receiving antenna 210 and the wireless charger 200. The matching network 225 is connected. The matching network 225 of the wireless charger 200 according to the embodiment of the present invention is composed of an adaptive matching network 225 that can adjust the frequency matching as needed.

That is, the capacitance of the entire adaptive matching network 225 may be changed by connecting an additional capacitor 227 in parallel to the matching circuit to switch the connection of the capacitor 227. That is, since the adaptive matching network 225 is configured to perform frequency matching with the wireless power supply device 100 when the switch 226 is turned off, the receiving antenna 210 is connected from the wireless power supply device 100. Receives wireless power and delivers it to rectifier 222. On the contrary, since the frequencies of the wireless power supply 100 and the wireless charger 200 do not match when the switch 226 is in an ON state, resonance does not occur between the wireless power supply 100 and the wireless charger 200. .

With the switch 226 OFF, the RF power received through the adaptive matching network 225 is converted into DC power through the rectifier 222, and the DC-DC converter 224 converts it to a voltage suitable for each load. Provide converted. That is, the rectifier 222 and the DC-DC converter 224 correspond to a power converter that converts the received RF power into DC power suitable for each load.

Here, the power control switch 223 is located between the rectifier 222 and the DC-DC converter 224, and the power control switch 223 is controlled so that power is transmitted or not transmitted to the load according to the ON / OFF. can do.

That is, when the power control switch 223 is ON, the received power is transferred to the load through the rectifier 222 and the DC-DC converter 224, but when the power control switch 223 is OFF, the received power is cut off. Since it is not consumed in the wireless charger 200, the energy corresponding to the received power is bounced back to other wireless chargers around to be used to charge another wireless charger.

Therefore, for the wireless charger to be charged, the switch 226 of the adaptive matching network 225 is turned off, and the rectifier (from the wireless power supply device 100 via the receiving antenna 210 and the adaptive matching network 225). Wireless power is transmitted to 222, and the power control switch 223 is turned on so that the received power is converted into a voltage suitable for each load by the DC-DC converter 224 and provided to the load.

On the other hand, even if wireless power is transmitted from the wireless power supply 100 to the rectifier 222 via the receiving antenna 210 and the adaptive matching network 225 by turning off the switch 226 of the adaptive matching network 225. If the power control switch 223 is OFF, the wireless power at this time is not consumed in the wireless charger 200, so the energy corresponding to the received power is bounced back to other wireless chargers around the other wireless charger. Since it can be used to charge the device, the wireless charger 200 serves as a repeater at this time.

This is particularly useful when there is a wireless charger that does not need to be charged between the wireless charger and the wireless power supply 100 to be charged. Since the wireless charger located in the center serves as a repeater, charging is not possible without a repeater. Efficiency can be increased, resulting in a wider range of charges.

As shown in FIG. 5, if there are wireless chargers 200_3 and 200_5 that do not require charging in the wireless chargers 200_4 and 200_6 and the wireless power supply 100 to be charged, the wireless power supply 100 ) Transmits a charging ON signal to the wireless chargers 200_4 and 200_6 to be charged, and transmits a repeater signal to the wireless chargers 200_3 and 200_5 that do not require charging.

The control unit 240 of the wireless chargers 200_4 and 200_6 receiving the charging ON signal turns off the switch 226 in the adaptive matching network, and the power control switch 223 is controlled to be turned on. The wireless chargers 200_4 and 200_6 may be in a state capable of receiving wireless power from the wireless power supply device 100.

In contrast, the wireless chargers 200_3 and 200_5 receiving the repeater signal control the two

switches

226 and 223 to be opened. Accordingly, the wireless chargers 200_3 and 200_5 may resonate with the wireless power supply device 100 and the other wireless chargers 200_4 and 200_6, but may not receive power to serve as repeaters.

Referring to FIG. 6, in contrast to the case of FIG. 5, the wireless chargers 200_7 and 200_9 to be charged are near the wireless power supply 100, and the wireless chargers 200_8 and 200_10 that do not require charging are wireless. Away from the power supply 100.

In the situation as shown in FIG. 6, when all of the wireless chargers 200_7, 200_8, 200_9, 200_10 resonate with the wireless power supply 100, power is transferred to the wireless chargers 200_8, 200_10 that do not require charging. This reduces the charging efficiency of the entire system.

Therefore, in this case, the frequency of the wireless chargers 200_8 and 200_10 is changed by turning on the switch 226 in the adaptive matching network 225 of the wireless chargers 200_8 and 200_10 that do not require charging. The 200_8 and 200_10 do not resonate with the wireless power supply device 100. In doing so, the wireless power transmitted from the wireless power supply device 100 can be delivered only to the wireless chargers 200_7 and 200_9 to be charged, thereby increasing the charging efficiency of the entire system.

According to the embodiment of the present invention as described above, in the multi-node wireless power transmission system using the magnetic resonance induction method, the charge / repeater based on the need to charge a plurality of wireless chargers and the distance from the wireless power supply device 100 It can be set to one of the on / off states and can optionally charge the wireless charger, thereby efficiently charging multiple wireless chargers.

Although the present invention has been described above with reference to preferred embodiments, the apparatus and method of the present invention are not necessarily limited to the above-described embodiments, and various modifications and variations can be made without departing from the spirit and scope of the invention. Accordingly, the appended claims will include such modifications and variations as long as they fall within the spirit of the invention.

Claims

A multi-node wireless power transfer system including a wireless power transmitter and a plurality of wireless chargers spaced apart from the wireless power transmitter,

The wireless power transmitter allocates one of charging, repeater, and off states to the wireless charger based on a distance between the wireless power transmitter and the wireless charger and whether the wireless charger needs to be charged.

The wireless charger controls an internal circuit according to the assigned state, and when the state of charge, the wireless charger matches the resonance frequency with the wireless power transmitter to receive wireless power transmitted from the wireless power transmitter in a magnetic resonance induction method. And a multi node matching the resonant frequency with the wireless power transmitter in the repeater state, but bounces the wireless power transmitted from the wireless power transmitter, and not resonating with the wireless power transmitter in the off state. Wireless power transfer system.
The wireless charger of claim 1,

A reception antenna for receiving wireless power transmitted from the wireless power transmission device;

A matching circuit connected to the receiving antenna and matching a resonant frequency between the wireless power transmitter and the wireless charger, a power control capacitor connected in parallel with the matching circuit, and one end of the matching circuit; A matching network including a matching switch connected to the other end and connected to the power control capacitor;

A rectifier connected to the matching network to rectify power supplied through the reception antenna;

A power control switch connected to a rear end of the rectifier;

And a DC-DC converter having one end connected to the power control switch and the other end connected to the load.
The method of claim 2, wherein the wireless charger,

In the charging state, the matching switch is turned off and the power control switch is turned on.

In the repeater state, the matching switch is turned off and the power control switch is turned off,

The multi-node wireless power transmission system to turn on the matching switch in the off state.
The method of claim 2,

And the power control capacitor has a capacity of 2 to 10 times the capacitance of the matching circuit.
The method of claim 1,

And the wireless power transmitter and the wireless charger each includes a magnetic field communication modem.
The method of claim 1,

The wireless power transmitter is a multi-node wireless power transmission system for receiving one or more information of the identification information, type, location, state of charge of the wireless charger from the wireless charger.
The wireless power transmitter of claim 1,

If there is a second wireless charger among the wireless charger that does not require charging between the first wireless charger that needs to be charged among the wireless chargers and the wireless power transmitter,

Assign the state of charge to the first wireless charger,

And assigning the repeater state to the second wireless charger.
The wireless power transmitter of claim 1,

When there is a first wireless charger of the wireless charger and a third wireless charger that is located farther from the wireless power transmitter than the first wireless charger of the wireless charger, and does not require charging,

Assign the state of charge to the first wireless charger,

And assigning the off state to the second wireless charger.
A method of charging a wireless charger in a multi-node wireless power transmission system comprising a wireless power transmitter and a plurality of wireless chargers spaced apart from the wireless power transmitter,

(a) a state in which the wireless charger is charged, repeater, or off in the wireless charger based on a distance between the wireless power transmitter and the wireless charger from the wireless power transmitter and whether the wireless charger needs to be charged Receiving a step,

(b) an internal circuit of the wireless charger to receive wireless power transmitted from the wireless power transmitter in a magnetic resonance induction manner by matching a resonant frequency with the wireless power transmitter when the wireless charger is allocated the state of charge; Controlling the;

(c) controlling an internal circuit of the wireless charger to match a resonant frequency with the wireless power transmitter when the wireless charger is assigned the repeater state, but to bounce the wireless power transmitted from the wireless power transmitter; Wow,

(d) controlling an internal circuit of the wireless charger so as not to self-resonate with the wireless power transmitter when the wireless charger is assigned the off state.
The method of claim 9, wherein the wireless charger,

A reception antenna for receiving wireless power transmitted from the wireless power transmission device;

A matching circuit connected to the receiving antenna and matching a resonant frequency between the wireless power transmitter and the wireless charger, a power control capacitor connected in parallel with the matching circuit, and one end of the matching circuit; A matching network including a matching switch connected to the other end and connected to the power control capacitor;

A rectifier connected to the matching network to rectify power supplied through the reception antenna;

A power control switch connected to a rear end of the rectifier;

A DC-DC converter having one end connected to the power control switch and the other end connected to a load;

The step (b) includes turning off the matching switch of the wireless charger and turning on the power control switch,

The step (c) includes turning off the matching switch of the wireless charger and turning off the power control switch,

The step (d) is the charging method of the multi-node wireless power transmission system comprising the step of turning on the matching switch of the wireless charger.
The method of claim 10,

The power control capacitor is a charging method of a multi-node wireless power transfer system having a capacity of 2 to 10 times the capacitance of the matching circuit.
The method of claim 9,

Before step (a) above,

And charging, by the wireless charger, at least one of identification information, type, location, and charging state of the wireless charger to the wireless power transmitter.
The method of claim 9, wherein step (a) comprises:

If there is a second wireless charger among the wireless charger that does not require charging between the first wireless charger that needs to be charged among the wireless chargers and the wireless power transmitter,

Receiving, by the first wireless charger, the state of charge;

And charging, by the second wireless charger, the repeater state.
The method of claim 9, wherein step (a) comprises:

When there is a first wireless charger of the wireless charger and a third wireless charger that is located farther from the wireless power transmitter than the first wireless charger of the wireless charger, and does not require charging,

Receiving, by the first wireless charger, the state of charge;

And charging, by the second wireless charger, the off state.