KR20120077444A - Multi-node wireless power transmission system and charging method therof based on battery information - Google Patents

Abstract

PURPOSE: A battery information based wireless power transmission system and a charging method thereof are provided to efficiently manage the charging process of a wireless power transmission system by preferentially charging a needed one of wireless chargeable devices. CONSTITUTION: A multi-node wireless power transmission system comprises a wireless power transmission device(100) using magnetic resonance induction and a plurality of wireless chargeable devices(200_1-200_N) that are located apart and provided with power wirelessly from the wireless power transmission device. A resonance channel is formed by aligning the resonance frequency between the wireless power transmission device and a wireless chargeable device. The wireless power transmission device can receive information on a wireless chargeable device, including the ID information, type, location, or charging state of the wireless chargeable device, through magnetic communication.

Description

Multi-node wireless power transmission system and charging method therof based on battery information}

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 select and charge a device that requires charging based on battery information, 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. .

However, when there are a plurality of receivers in a system for transmitting energy wirelessly using resonance, power is transmitted to all receiver apparatuses where resonance occurs, which is inefficient.

SUMMARY OF THE INVENTION The present invention has been made in the technical background as described above, and provides a multi-node wireless power transmission system of a self-resonance induction method and a charging method thereof which preferentially charge a device urgently charged among a plurality of wireless chargers. Shall be.

Another object of the present invention is to provide a system capable of selectively charging a device requiring charging in a multi-node wireless power transmission system of a magnetic resonance induction method and a charging method thereof.

In order to solve the above problems, the present invention checks the battery state of each wireless charger within the charging range through magnetic field communication, and then charges the wireless charger with the lowest battery remaining by giving priority to charging. In addition, when a new wireless charger enters the charging range, it rechecks the battery status of each wireless charger and dynamically assigns priority.

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: Receives battery status information of a wireless charger, gives a priority to charge to the first wireless charger with the least battery remaining among the wireless charger, and the other wireless charger-second wireless charger other than the first wireless charger -Controls the internal circuit so that the wireless power transmitted from the wireless power transmitter is not transmitted to the load of the second wireless charger.

The wireless charger includes a reception antenna for receiving the wireless power, a rectifier for rectifying the power supplied through the reception antenna, a power control switch connected to a rear end of the rectifier, and one end of the wireless control device connected to the power control switch. And a DC-DC converter connected to the other end of the load, and controlling the power control switch to be ON / OFF to control the transmission of the wireless power to the load.

The wireless charger may further include: a matching circuit connected to the reception antenna and matching a resonant frequency between the wireless power transmitter and the wireless charger, and a power control capacitor connected in parallel with the matching circuit. And a matching network, the matching switch having one end connected to the matching circuit and the other end connected to the power control capacitor, wherein the matching switch, the power control switch, or both the matching switch and the power control switch are turned on. It is also possible to control the transfer of power to the load by controlling / OFF.

Preferably, the wireless power transmitter and the wireless charger each include a magnetic field communication modem.

The wireless charger may be connected to a reception antenna for receiving wireless power transmitted from the wireless power transmitter and the reception antenna, and to match a resonant frequency between the wireless power transmitter and the wireless charger. A matching network including a matching circuit, 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. And a rectifier for rectifying the power supplied through the receiving antenna, and a DC-DC converter having one end connected to the rectifier and the other end connected to a load, wherein the power control capacitor includes capacitance of the matching circuit. It is preferred to have a capacity of 2 to 10 times.

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 method of charging, the wireless power transmitter checks whether a new wireless charger has entered a chargeable range, and when the new wireless charger enters, a battery from the plurality of wireless chargers including the new wireless charger. Receiving information, assigning a priority to charging to a first wireless charger having the least battery remaining among the plurality of wireless chargers based on the battery information, and the wireless charger other than the first wireless charger Charge-Off Control with-2nd Wireless Charger And transmitting the signal.

After the transmitting of the charge-off control signal, the method may further include transmitting a predetermined amount of wireless power to the first wireless charger having the charging priority.

The wireless charger includes a reception antenna for receiving the wireless power, a rectifier for rectifying the power supplied through the reception antenna, a power control switch connected to a rear end of the rectifier, and one end of the wireless control device connected to the power control switch. And a DC-DC converter connected to the other end of the load, and the transmitting of the charge-off control signal may include transmitting a signal of turning off the power control switch.

The wireless charger may be connected to a reception antenna for receiving wireless power transmitted from the wireless power transmitter and the reception antenna, and to match a resonant frequency between the wireless power transmitter and the wireless charger. A matching network including a matching circuit, 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. And a rectifier for rectifying the power supplied through the receiving antenna, and a DC-DC converter having one end connected to the rectifier and the other end connected to a load, and transmitting the charge-off control signal to the matching switch. And transmitting the signal to be turned on.

According to the present invention, in the multi-node wireless power transmission system using the magnetic resonance induction method, it is possible to efficiently manage the charging process of the entire multi-node wireless power transmission system by first charging the urgently charged devices among the plurality of 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, 5, and 7 are block diagrams illustrating the configuration of a power management unit of the wireless charger according to various embodiments of the present invention, respectively.
6 is a diagram illustrating a configuration of a receiving antenna and an adaptive matching network according to an embodiment of the present invention.

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. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. 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).

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 between the wireless power supply device 100 and the wireless charger 200 to form a resonant channel and transmit wireless power therethrough.

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 the remaining battery information of the wireless charger (200_1, 200_2, .., 200_N) through the magnetic field communication with the wireless charger (200_1, 200_2, .., 200_N) Acquire it.

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.

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.

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 checks whether a new wireless charger has entered a chargeable range (S310).

When a new wireless charger is entered, all wireless chargers 200_1, 200_2, .., 200_N, including the new wireless charger, communicate with each other by using a magnetic field communication protocol to communicate with each wireless charger 200_1, 200_2, .., 200_N to check the battery state (S320). In this case, in addition to the battery state of the charger, information such as identification information, type or location of the charger may be further received.

Next, the wireless power supply device 100 gives priority to charging to the charger having the lowest remaining battery level among the wireless chargers 200_1, 200_2,..., 200_N using the received battery state information (S330).

Next, the wireless power supply 100 selectively transmits power to a charger having a charging priority (S340).

When the amount of charge reaches a predetermined set amount, for example, 5% or 10% (S350), the wireless power supply device 100 returns to step S320 and the wireless chargers 200_1, 200_2,... 200_N) to check the battery state (S320).

However, even if the charge amount does not reach the predetermined set amount (S350), when a new wireless charger enters the chargeable range, the wireless power supply device 100 is present in each of the wireless chargers 200_1, 200_2, .., 200_N) to check the battery state (S320).

In this way, the battery status can be dynamically checked to give the priority of charging to the charger having the lowest battery level, thereby allowing the device to be charged to be charged first.

In order to selectively transmit power to a charger having a charging priority, the wireless power transmitter 100 transmits a command to control the ON / OFF of the charging function to each of the wireless chargers 200_1, 200_2, .., 200_N. The internal circuits of the wireless chargers 200_1, 200_2,..., 200_N are controlled.

Now let's take a closer look at how each wireless charger controls its internal circuitry to turn the charging function on and off.

4 to 6 are block diagrams illustrating various configurations of the power management unit of the wireless charger according to the embodiment of the present invention.

First, referring to FIG. 4, the power manager 220_1 includes a matching network 221, 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 matching network 221 adjusts the frequency so that the wireless power supply device 100 and the wireless charger 200 resonate, and performs impedance matching between the reception antenna 210 and the wireless charger 200.

The RF power received through the matching network 221 is converted into DC power through the rectifier 222, the DC-DC converter 224 converts it to a voltage for each load and provides it. 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, by turning on / off this power control switch 223 to turn on the charging function of the wireless charger 200. You can / OFF.

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.

FIG. 5 shows a configuration of a power management unit according to another embodiment. In the embodiment shown in FIG. 5, a switch is installed in a matching network instead of a power control switch between a rectifier and a DC-DC converter.

Referring to FIG. 5, in the power manager 220_2 according to another embodiment of the present invention, instead of the matching network 221 shown in FIG. 4, an adaptive matching network 225 capable of adjusting frequency matching as needed. ). That is, the power manager 220_2 includes an adaptive matching network 225, a rectifier 222, and a DC-DC converter 224. The DC-DC converter 224 is connected with a load (Fig. 2: 250) as in the embodiment of Fig. 4.

The configuration of the adaptive matching network 225 is shown in detail in FIG.

The adaptive matching network 225 may change the capacitance of the entire adaptive matching network 225 by connecting additional capacitors 227 in parallel to the matching circuit to switch connections with the corresponding capacitor 227. Among the matching circuits, Cr is a capacitor for matching resonance with the wireless power supply device 100, and Cm is a capacitor for impedance matching. In addition, the capacitor Ct 227 for adjusting the resonance frequency is further connected and controlled using the switch 226.

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. .

On the other hand, by adjusting the capacitance of the capacitor 227, the function as the charge function ON / OFF switch can be optimized. In order to cut off most of the power transmitted by the wireless power supply device 100, it is preferable that the capacitor 227 has a capacity of 2 to 10 times the capacitance of the matching circuit.

If necessary, both adaptive matching networks and power disconnect switches can be used. 7 shows such an embodiment.

As shown in FIG. 7, the power manager 220_3 includes an adaptive matching network 225, a rectifier 222, a power cutoff switch 223, and a DC-DC converter 224. In this case, only the switch 226 or the power cutoff switch 223 in the adaptive matching network 225 may be used as needed, or both switches 226 and 223 may be used.

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.

100: wireless power transmitter 200: wireless charger
110: transmit antenna 120: power converter
130: magnetic field communication modem 140: control unit
210: receiving antenna 220: power management unit
230: magnetic field communication modem 240: control unit
250: load 222: rectifier 223: power control switch 224: DC-DC converter 225: adaptive matching network

Claims (11)

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 receives the battery state information of the wireless charger, and gives a priority to charge to the first wireless charger with the smallest remaining battery of the wireless charger,
The wireless charger other than the first wireless charger-the second wireless charger-controls an internal circuit so that the wireless power transmitted from the wireless power transmitter is not transmitted to the load of the second wireless charger. Node wireless power transfer system. The method of claim 1,
The wireless charger,
A reception antenna for receiving the wireless power;
A rectifier for rectifying power supplied through the receiving 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;
Multi-node wireless power transmission system for controlling the transmission of the wireless power to the load by controlling the power control switch ON / OFF. The method of claim 2,
The wireless charger,
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; The matching switch is connected to the other end is connected to the power control capacitor further comprises a matching network,
And controlling the transfer of power to the load by ON / OFF control of the matching switch, the power control switch, or both the matching switch and the power control switch. 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 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;
And a DC-DC converter, one end of which is connected to the rectifier and the other end of which is connected to a load. The method of claim 5,
And the power control capacitor has a capacity of 2 to 10 times the capacitance of the matching circuit. 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,
Checking, by the wireless power transmitter, whether a new wireless charger has entered a chargeable range;
When the new wireless charger enters, receiving battery information from the plurality of wireless chargers including the new wireless charger;
Assigning a charging priority to a first wireless charger having the lowest battery remaining among the plurality of wireless chargers based on the battery information;
And transmitting a charge-off control signal to the wireless charger other than the first wireless charger, to a second wireless charger. The method of claim 7, wherein
After transmitting the charge off control signal,
And transmitting a predetermined amount of wireless power to the first wireless charger having the charging priority. The method of claim 7, wherein
The wireless charger,
A reception antenna for receiving the wireless power;
A rectifier for rectifying power supplied through the receiving 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 transmitting of the charge off control signal may include:
And transmitting a signal to turn off the power control switch. The method of claim 7, 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 DC-DC converter having one end connected to the rectifier and the other end connected to a load;
The transmitting of the charge off control signal may include:
And transmitting a signal to turn on the matching switch. The method of claim 10,
The power control capacitor is a charging method of a multi-node wireless power transmission system having a capacity of 2 to 10 times the capacitance of the matching circuit.

Images