KR20150059069A - Wireless power transmitter and method for controlling the same - Google Patents

Abstract

The present invention relates to a wireless power transmitter which can detect not only existence of an external metal material, but also energy consumed by the external metal material, and to a method for controlling the same. The wireless power transmitter according to the present invention detects power lost by the external metal material, and outputs information presenting the detected power. The wireless power transmitter available of wireless power transmission and reception includes a power supply part supplying power to wirelessly transmit the power to a receiving apparatus; and a power transmission control part which periodically generates waveform of specific frequency to measure a damping coefficient of the waveform of each period and measure the amount of change in the damping coefficient of each period to determine the type of the external material, wherein the power transmission control part is characterized by determining whether to wirelessly transmit power to the receiving apparatus based on the type of the external material.

Description

[0001] WIRELESS POWER TRANSMITTER AND METHOD FOR CONTROLLING THE SAME [0002]

TECHNICAL FIELD [0001] The present invention relates to a wireless power transmission apparatus and a control method thereof.

In general, instead of a method of supplying electrical energy to a wireless power receiving apparatus by wire, recently, a method of wirelessly supplying electric energy without contacting is used. A wireless power receiving apparatus that receives energy wirelessly may be driven directly by the received wireless power, or may be powered by the charged power by charging the battery using the received wireless power.

The Wireless Power Consortium, which deals with techniques for wireless power transmission of a self-induction type, is entitled " Wireless Power Transmission System Manual, Volume I, " on April 12, 2010 for interoperability in wireless power transmission, Low Power, Part 1: Interface Definition, Version 1.00 RC1 (System Description Wireless Power Transfer, Volume 1, Low Power, Part 1: Interface Definition, Version 1.00 Release Candidate 1) The standard document of the Wireless Power Association describes a method of transferring power from one wireless power transmission device to one wireless power receiving device by a magnetic induction method.

It is an object of the present invention to provide a wireless power transmission apparatus and a control method thereof capable of detecting not only the presence or absence of an external metallic material, but also the amount of power consumed by the external metallic material.

It is another object of the present invention to provide a wireless power transmission apparatus and a control method thereof capable of detecting various information related to an external material.

It is another object of the present invention to provide a wireless power transmission apparatus capable of secure one-to-one communication and a control method thereof.

A wireless power transmission apparatus according to the present invention is a wireless power transmission apparatus for transmitting wireless power to an electronic apparatus to which a wireless power receiving apparatus is applied, the apparatus comprising: a power supply unit for supplying an input voltage; A power transmission control unit for generating a driving signal for the first antenna; And a power conversion unit that forms a wireless power signal based on the switching operation by the supplied input voltage and the driving signal and transmits wireless power to the wireless power receiving apparatus, And outputs information indicating the detected power.

The power transmission control unit may generate error information indicating that power is lost due to the external metallic material when power loss due to the external metallic material is detected, And can be displayed on the display unit of the wireless power transmission apparatus.

As an example related to the present specification, the power transmission control unit controls the wireless power receiving apparatus so that the wireless power receiving apparatus blocks reception of the wireless power, drives the LC resonant circuit of the wireless power transmission apparatus The total amount of loss power lost in the radio power transmission apparatus at the time of stopping is detected and a difference value between the detected total loss power amount and the loss intrinsic power amount of the radio power transmission apparatus is determined as the amount of power consumed due to the external metallic material have.

As an example related to the present specification, the display device may further include a display unit for displaying an amount of power consumed by the external metal material.

As an example related to the present specification, the power transmission control unit may include a frequency value for driving an LC resonant circuit of the wireless power transmission apparatus, an inductor (L) value of an LC resonant circuit of the wireless power transmission apparatus, The total loss power amount can be detected based on the current value of the LC resonance circuit of the transmission apparatus.

As an example related to the present specification, the current value of the LC resonant circuit of the wireless power transmission apparatus may be a current value of a predetermined period after the LC resonant circuit of the wireless power transmission apparatus is driven and stopped, The first current value of the inductor L detected at the first time point and the second current value of the inductor L detected at the second time point at which the second predetermined time or the predetermined number of cycles have elapsed since the point at which the LC resonance circuit of the radio- Represents the difference value of the second current value of the inductor L, and the first time point may be faster than the second time point.

As an example related to the present specification, the power transmission control unit may be configured such that, when the wireless power receiving apparatus is disconnected from the wireless power transmission apparatus, at a time point when the driving of the LC resonant circuit of the wireless power transmission apparatus is suspended , The attenuation coefficient of the resonance energy of the LC resonance circuit of the wireless power transmission apparatus is detected and the presence or absence of the external metallic substance can be determined based on the detected attenuation coefficient and the reference attenuation coefficient.

As an example related to the present specification, the power transmission control unit may be configured to control the wireless power receiving apparatus to wirelessly receive the wireless power when the wireless power receiving apparatus is connected to the wireless power transmitting apparatus, And when the driving of the LC resonant circuit of the wireless power transmission apparatus is temporarily stopped, the attenuation coefficient of the resonant energy of the LC resonant circuit of the wireless power transmission apparatus is detected, and the detected attenuation coefficient and the reference attenuation coefficient The presence or absence of the external metal material can be determined.

As an example related to the present specification, the power transmission control unit may detect power that causes heat generation of the external metallic material.

A method of controlling a wireless power transmission apparatus according to the present invention is a method of controlling a wireless power transmission apparatus that transmits wireless power to an electronic apparatus to which a wireless power receiving apparatus is applied, A counter for generating a driving signal; Forming a wireless power signal based on an input voltage and a switching operation by the driving signal to transmit wireless power to the wireless power receiving apparatus; Detecting power lost due to the external metallic material; And outputting information indicating the detected power.

The present invention relates to a wireless power transmission apparatus capable of wirelessly transmitting and receiving power, comprising: a power supply unit for supplying power to a receiving apparatus to transmit power wirelessly; and a power supply unit for periodically generating a waveform of a specific frequency, And a power transmission control unit for measuring a damping coefficient and measuring a change amount of a damping coefficient in each cycle to determine a type of the external material, wherein the power transmission control unit controls the power supply to the reception device And determines whether or not to transmit power wirelessly.

In one embodiment of the present invention, the power transmission control unit detects a variation amount of the attenuation coefficient varying according to the period of the waveform, and when the variation amount of the attenuation coefficient matches the predetermined reference variation amount, It is determined that the receiving apparatus is a power receiving apparatus, and power is transmitted to the receiving apparatus wirelessly.

The wireless transmission unit may further include a wireless communication unit configured to wirelessly communicate with the reception apparatus, wherein, when the external material is a reception apparatus that receives the wireless power, And transmits the predetermined amount of power and communication information related to the communication to the receiving device so that the communication is performed.

In one embodiment of the present invention, when the one-to-one communication with the receiving apparatus is completed, the power transmission control unit transmits power to the receiving apparatus wirelessly.

As an example related to the present specification, the power transmission control unit receives the power amount information for receiving the radio power from the reception apparatus through the connected communication, and controls the power supply unit to supply power based on the power amount information .

According to one embodiment of the present invention, when receiving the alignment status information indicating that the alignment status of the reception apparatus has changed from the reception apparatus through the connected communication, the power transmission control unit may transmit the power supplied to the reception apparatus Stopping.

In one embodiment of the present invention, the power transmission control unit periodically generates the waveform of the specific frequency, and then, when a frequency different from a predetermined resonance frequency is detected, .

As an example related to the present specification, the power transmission control unit detects the type of the external material based on the characteristics of the other frequency, and determines the amount of power to be transmitted wirelessly based on the type of the external material .

As an example related to the present specification, the power transmission control unit detects the capacity of the external material based on the rate of change of the attenuation coefficient of the other frequency.

A wireless charging system for wirelessly transmitting power, comprising: a transmitting device configured to transmit power wirelessly; and a receiving device configured to receive wireless power from the transmitting device, wherein the transmitting device wirelessly powers the receiving device A power supply for supplying electric power to be transmitted; And periodically generating a waveform of a specific frequency, measuring a damping coefficient of the waveform in each of the periods, measuring a change amount of the damping coefficient in each period, and determining whether or not to transmit power wirelessly to the receiving apparatus And a power transmission control unit.

In one embodiment of the present invention, the transmitting apparatus further includes a wireless communication unit configured to wirelessly communicate with the receiving apparatus, and the power transmission control unit may transmit the power to the receiving apparatus And transmits communication information and a predetermined amount of power to the receiving apparatus to perform wireless communication.

In one embodiment of the present invention, the power transmission control unit transmits the communication information and a predetermined amount of power using a frequency higher than a resonance frequency of the transmission apparatus.

As an example related to the present specification, the power transmission control unit may control the power transmission control unit to transmit power based on the amount of power received from the receiving apparatus through the communication, when a communication is established with the receiving apparatus, The control unit controls the control unit.

As an example related to the present specification, the power transmission control unit controls the power supply unit to stop the power being transmitted when a request signal is received to stop power transmission from the receiving apparatus.

According to one embodiment of the present invention, the receiving apparatus generates the request signal based on at least one of a voltage value, a voltage drop time, and a current value of the receiving apparatus.

A wireless power transmission method of a wireless power transmission apparatus for wirelessly transmitting power, the wireless power transmission method comprising the steps of: periodically generating a waveform of a specific frequency; and calculating, based on the amount of change of the attenuation coefficient in each period of the specific frequency waveform, When the power receiving device is detected, communicating communication connection information for communicating with the transmitting device and power used for the communication module of the receiver to the power receiving device, Connecting a communication with the receiving apparatus using the communication unit; And receiving power amount information to be wirelessly transmitted from a receiving apparatus using the connected communication, and transmitting power wirelessly based on the received power amount information. In the step of detecting the power receiving apparatus, A waveform of a frequency is periodically generated, a decay rate in each period is measured, and a receiver is detected using a variation amount of a plurality of decay rates.

According to an embodiment of the present invention, in the step of detecting the power receiving apparatus, an alignment state of the receiving apparatus is determined using a waveform having a frequency different from a resonant frequency of the transmitting apparatus.

In one embodiment of the present invention, in the step of transmitting the communication connection information to the power receiving device, the communication connection information is transmitted using a frequency higher than the resonant frequency of the transmitting device.

As one example related to the present specification, the transmitting apparatus communicates with the receiving apparatus on a one-to-one basis.

As an example related to the present specification, the step of wirelessly transmitting power to the receiving device may include stopping transmission of the power based on receiving a request signal to stop transmission of power from the receiving device via the communication .

The wireless power transmission apparatus and the control method thereof according to the embodiments of the present invention can determine the presence or absence of the external metallic material by detecting the attenuation coefficient of the resonance energy of the LC resonance circuit of the wireless power transmission apparatus.

A wireless power transmission apparatus and a control method thereof according to embodiments of the present invention are characterized in that the wireless power reception apparatus controls the wireless power reception apparatus to block the reception of the wireless power and the LC resonance circuit of the wireless power transmission apparatus The amount of power consumed by the external metallic material may be detected on the basis of the total loss power amount of the wireless power transmission apparatus detected at the time of driving and stopping and the loss intrinsic power amount of the wireless power transmission apparatus.

The wireless power transmission apparatus and the control method thereof according to embodiments of the present invention can determine the type of the external material by using the variation amount of the frequency attenuation coefficient of the waveform sensed by the power transmission coil of the wireless power transmission apparatus.

The wireless power transmission apparatus and the control method thereof according to embodiments of the present invention are characterized in that a waveform sensed by a power transmission coil of a wireless power transmission apparatus uses an additional waveform other than the inherent resonance frequency, Can be detected.

A wireless power transmission apparatus and a control method thereof according to an embodiment of the present invention can provide a method of connecting one-to-one communication between a wireless power transmission apparatus and a wireless power reception apparatus. Accordingly, the present invention can provide a method for securely performing communication.

1 is an exemplary diagram conceptually showing a wireless power transmission device and an electronic device according to embodiments of the present invention.
2 (a) and 2 (b) are block diagrams illustrating exemplary configurations of a wireless power transmission device and an electronic device that can be employed in the embodiments disclosed herein.
FIG. 3 illustrates a concept that power is transmitted from a wireless power transmission apparatus to an electronic apparatus wirelessly according to an inductive coupling scheme.
4A and 4B are block diagrams exemplarily showing a part of the configuration of an electromagnetic induction type wireless power transmission apparatus and an electronic apparatus that can be employed in the embodiments disclosed herein.
5 is a block diagram of a wireless power transmission apparatus configured to have one or more transmission coils that receive power in accordance with an inductive coupling scheme employable in the embodiments disclosed herein.
6 shows a concept that power is transferred from a wireless power transmission device to an electronic device wirelessly according to a resonant coupling scheme.
7 is a block diagram exemplarily showing a part of the configuration of a wireless power transmission apparatus and an electronic apparatus in a resonance system that can be employed in the embodiments disclosed herein.
8 is a block diagram of a wireless power transmission apparatus configured to have one or more transmission coils that receive power in accordance with a resonant coupling scheme employable in the embodiments disclosed herein.
FIG. 9 is a block diagram showing a wireless power transmission apparatus further including an additional configuration in addition to the configuration shown in FIG. 2 (a).
FIG. 10 shows a configuration in which an electronic device according to the embodiments disclosed herein is implemented in the form of a mobile terminal.
11 illustrates the concept of transmitting and receiving packets between a wireless power transmission device and an electronic device through modulation and demodulation of a wireless power signal in the wireless power transmission disclosed herein.
12 shows a method of displaying data bits and bytes constituting a power control message by the wireless power transmission apparatus.
FIG. 13 illustrates a packet including a power control message used in a wireless power transfer method in accordance with the embodiments disclosed herein.
14 illustrates operating states of a wireless power transmission device and an electronic device according to the embodiments disclosed herein.
15 to 19 show the structure of packets including power control messages between the wireless power transmission apparatus and the electronic apparatuses.
20 is an exemplary view showing a cause of heat generation of an external metallic material disposed in the wireless power transmission apparatus 100 according to an embodiment of the present invention.
FIG. 21 is an exemplary view illustrating an outer metallic material located between a wireless power transmission apparatus using a flux-linkage and a wireless power receiving apparatus according to an embodiment of the present invention.
22A and 22B are diagrams illustrating changes in inductor (L) current when the inverter of the wireless power transmission apparatus drives the LC resonance circuit and stops driving temporarily according to an embodiment of the present invention.
23 shows the attenuation curve of the resonance energy when the driving of the LC resonant circuit of the wireless power transmission apparatus is stopped in the state that the wireless power receiving apparatus 200 and the wireless power transmission apparatus are absent without external metal material.
Fig. 24 is an exemplary diagram showing a circuit for setting PT = 0; Fig.
Fig. 25 is an exemplary diagram showing another circuit for setting PT = 0; Fig.
26 shows the attenuation curve of the resonance energy when the driving of the LC resonance circuit of the wireless power transmission apparatus is stopped in the state that only the wireless power receiving apparatus and the wireless power transmission apparatus exist without the external metallic material.
FIG. 27 is a diagram showing a waveform in which the current waveform of FIG. 23 and the current waveform of FIG. 26 are overlapped.
28 is an exemplary view showing a damping curve (damping coefficient) of the resonance energy.
Fig. 29 is another example showing a resonance energy attenuation curve (attenuation coefficient).
30 is a flowchart illustrating a method for determining the presence or absence of the external metal material according to an embodiment of the present invention.
31 is a flowchart illustrating another method for determining the presence or absence of the external metal material according to an embodiment of the present invention.
32 is a flowchart showing a method of detecting the type of foreign substance, the alignment state and the capacitance of the receiving apparatus based on the rate of change per period of the attenuation coefficient.
Figs. 35, 36, and 37 are graphs showing changes in attenuation coefficient depending on the kind of external material, and Figs. 38, 39, and 40 are graphs showing changes in attenuation coefficient per each period when a receiving apparatus is provided .

The techniques disclosed herein apply to wireless power transmission. However, the technology disclosed in this specification is not limited thereto, and can be applied to all power transmission systems and methods, wireless charging circuits and methods, and other methods and apparatus that utilize wirelessly transmitted power to which the technical idea of the technology can be applied .

It is noted that the technical terms used herein are used only to describe specific embodiments and are not intended to limit the invention. It is also to be understood that the technical terms used herein are to be interpreted in a sense generally understood by a person skilled in the art to which the present invention belongs, Should not be construed to mean, or be interpreted in an excessively reduced sense. Further, when a technical term used herein is an erroneous technical term that does not accurately express the spirit of the present invention, it should be understood that technical terms that can be understood by a person skilled in the art are replaced. In addition, the general terms used in the present invention should be interpreted according to a predefined or prior context, and should not be construed as being excessively reduced.

Also, the singular forms "as used herein include plural referents unless the context clearly dictates otherwise. In the present application, the term "comprising" or "comprising" or the like should not be construed as necessarily including the various elements or steps described in the specification, Or may be further comprised of additional components or steps.

Furthermore, suffixes "module" and " part "for components used in the present specification are given or mixed in consideration of ease of specification, and do not have their own meaning or role.

Furthermore, terms including ordinals such as first, second, etc. used in this specification can be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like or similar elements throughout the several views, and redundant description thereof will be omitted.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. It is to be noted that the accompanying drawings are only for the purpose of facilitating understanding of the present invention, and should not be construed as limiting the scope of the present invention with reference to the accompanying drawings.

Justice

Many-to-one communication method: how one transmitter (Tx) communicates with multiple receivers (Rx)

Unidirectional communication: a communication method in which a receiver only sends a necessary message to the transmitter side

Bidirectional communication: A transmitter is a receiver and a receiver is a transmitter, that is, a communication method capable of transmitting messages on both sides

Here, the transmitter and the receiver are the same as the transmitter and the receiver, respectively, and these terms can be used in combination.

Wireless power transmission device and wireless power receiving device conceptual diagram

FIG. 1 is an exemplary view conceptually showing a wireless power transmission apparatus and a wireless power reception apparatus according to embodiments of the present invention.

1, the wireless power transmission apparatus 100 may be a power transmission apparatus that transmits power wirelessly required by the wireless power receiving apparatus 200. [

The wireless power transmission apparatus 100 may be a wireless charging apparatus that charges the battery of the wireless power receiving apparatus 200 by transmitting power wirelessly.

In addition, the wireless power transmission apparatus 100 may be implemented as various types of devices that transmit power to the wireless power receiving apparatus 200 that requires power in a non-contact state.

The wireless power receiving apparatus 200 is a device capable of receiving power wirelessly from the wireless power transmission apparatus 100 and operating. Also, the wireless power receiving apparatus 200 can charge the battery using the received wireless power.

Meanwhile, the wireless power receiving apparatus that receives power wirelessly as described in the present specification may be any portable electronic apparatus such as a keyboard, a mouse, an auxiliary output device such as a video or audio auxiliary output device, a cellular phone, a cellular phone, A smart phone, a PDA (Personal Digital Assistants), a PMP (Portable Multimedia Player), a tablet, or a multimedia device.

The wireless power receiving apparatus 200 may be a mobile communication terminal (e.g., a cellular phone, a cellular phone, a tablet) or a multimedia device, as described later.

Meanwhile, the wireless power transmission apparatus 100 may transmit power wirelessly to the wireless power receiving apparatus 200 without mutual contact using one or more wireless power transmission methods. That is, the wireless power transmission apparatus 100 uses an inductive coupling scheme based on a magnetic induction phenomenon by the wireless power signal, and a magnetic resonance coupling based on an electromagnetic resonance phenomenon by a wireless power signal of a specific frequency ) ≪ / RTI >

The inductive coupling type wireless power transmission is a technique of wirelessly transmitting power by using a primary coil and a secondary coil, and a current is induced to the other coil through a magnetic field changing in one coil due to the magnetic induction phenomenon, .

In the wireless power transmission by the resonance coupling method, resonance occurs in the wireless power receiving apparatus 200 due to a wireless power signal transmitted from the wireless power transmission apparatus 100, (100) to the wireless power receiving apparatus (200).

Hereinafter, embodiments of the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 disclosed in the present specification will be described in detail. In the drawings, the same reference numerals as possible are used to denote the same or similar components, even if they are shown in different drawings.

2A and 2B are block diagrams illustrating a configuration of a wireless power transmission apparatus 100 and a wireless power receiving apparatus 200 that can be employed in the embodiments disclosed herein.

Wireless power transmission device

Referring to FIG. 2A, the wireless power transmission apparatus 100 is configured to include a power transmission unit 110. FIG. The power transmission unit 110 may include a power conversion unit 111 and a power transmission control unit 112.

The power conversion unit 111 converts the power supplied from the transmission power supply unit 190 into a wireless power signal and transmits the wireless power signal to the wireless power reception apparatus 200. The radio power signal transmitted by the power converter 111 is formed in the form of a magnetic field or an electro-magnetic field having oscillation characteristics. For this, the power conversion unit 111 may be configured to include a coil for generating the wireless power signal.

The power conversion unit 111 may include components for forming different types of wireless power signals according to each power transmission scheme. For example, the power conversion unit 111 may be configured to include a primary coil that forms a changing magnetic field in order to induce a current in the secondary coil of the wireless power receiving apparatus 200 according to an inductive coupling scheme have. The power conversion unit 111 may be configured to include a coil (or antenna) that forms a magnetic field having a specific resonance frequency in order to generate a resonance phenomenon in the wireless power receiving apparatus 200 according to a resonance coupling scheme have.

The power conversion unit 111 may transmit power using one or more of the inductive coupling method and the resonant coupling method described above.

Referring to FIGS. 4A, 4B, and 5, the components of the power conversion unit 111 that follow the inductive coupling scheme will be described with reference to FIGS. 7 and 8. FIG. Described below.

The power conversion unit 111 may further include a circuit for adjusting characteristics of a frequency, an applied voltage, and a current used for forming the wireless power signal.

The power transmission control unit 112 controls each component included in the power transmission unit 110. The power transmission control unit 112 may be integrated with another control unit (not shown) that controls the wireless power supply apparatus 100.

Meanwhile, an area where the wireless power signal can reach can be divided into two types. First, an active area refers to a region through which a wireless power signal that transmits power to the wireless power receiving apparatus 200 passes. Next, a semi-active area refers to an area of interest in which the wireless power transmission apparatus 100 can detect the presence of the wireless power receiving apparatus 200. [ Here, the power transmission control unit 112 may detect whether the wireless power receiving apparatus 200 is placed in or removed from the active region or the sensing region. Specifically, the power transmission control unit 112 uses the wireless power signal generated by the power conversion unit 111 or the wireless power reception apparatus 200 is connected to the active area or the sensing area by a separately provided sensor It can be detected whether or not it has been deployed. For example, the power transmission control unit 112 receives the wireless power signal due to the wireless power receiving apparatus 200 existing in the sensing area, and forms the wireless power signal of the power conversion unit 111 The presence of the wireless power receiving apparatus 200 can be detected by monitoring whether or not the characteristic of the power for the wireless power receiving apparatus 200 changes. However, the active area and the sensing area may differ depending on a wireless power transmission scheme such as an inductive coupling scheme and a resonant coupling scheme.

The power transmission control unit 112 may perform the process of identifying the wireless power receiving apparatus 200 according to a result of detecting the presence of the wireless power receiving apparatus 200 or may determine whether to start wireless power transmission have.

The power transmission control unit 112 may determine at least one of a frequency, a voltage, and a current of the power conversion unit 111 for forming the wireless power signal. The determination of the characteristics may be made according to conditions on the side of the wireless power transmission apparatus 100 or on conditions on the side of the wireless power reception apparatus 200. [

The power transmission control unit 112 may receive a power control message from the wireless power receiving apparatus 200. [ The power transmission control unit 112 may determine one or more characteristics of the frequency, voltage, and current of the power conversion unit 111 based on the received power control message, Operation can be performed.

For example, the power transmission control unit 112 may form the wireless power signal according to a power control message including at least one of the rectified power amount information, the charging status information and the identification information of the wireless power receiving apparatus 200 It is possible to determine at least one of the characteristics of the frequency, current, and voltage to be used.

In addition, as another control operation using the power control message, the wireless power transmission apparatus 100 may perform a general control operation related to wireless power transmission based on the power control message. For example, the wireless power transmission apparatus 100 receives information to be output audibly or visually related to the wireless power receiving apparatus 200 through the power control message, or receives information necessary for authentication between devices It is possible.

In order to receive the power control message, the power transmission control unit 112 may use at least one of a method of receiving through the wireless power signal and a method of receiving other user data.

In order to receive the power control message, the wireless power transmission apparatus 100 may further include a power communication modulation / demodulation unit 113 electrically connected to the power conversion unit 111 . The modem unit 113 may be used to demodulate the wireless power signal modulated by the wireless power receiving apparatus 200 and receive the power control message.

In addition, in some embodiments, the power transmission control unit 112 receives user data including a power control message by communication means (not shown) included in the wireless power transmission apparatus 100, .

[When supporting in-band two-way communication]

In addition, in the wireless power transmission environment capable of bidirectional communication according to the embodiments disclosed herein, the power transmission control unit 112 may transmit data to the wireless power receiving apparatus 200. [ The data transmitted by the power transmission control unit 112 may be a request for the wireless power receiving apparatus 200 to send a power control message.

Wireless power receiving device

Referring to FIG. 2B, the wireless power receiving apparatus 200 is configured to include a power supply unit 290. The power supply unit 290 supplies power required for operation of the wireless power receiving apparatus 200. The power supply unit 290 may include a power receiving unit 291 and a power receiving control unit 292.

The power receiving unit 291 receives power transmitted from the wireless power transmission apparatus 100 wirelessly.

The power receiving unit 291 may include components necessary for receiving the wireless power signal according to a wireless power transmission scheme. In addition, the power receiver 291 may receive power according to one or more wireless power transmission schemes. In this case, the power receiver 291 may include necessary components according to each scheme.

First, the power receiving unit 291 may be configured to include a coil for receiving a radio power signal transmitted in the form of a magnetic field or an electromagnetic field having an oscillating characteristic.

For example, as a component according to an inductive coupling scheme, the power receiving unit 291 may include a secondary coil whose current is induced by a changing magnetic field. The power receiving unit 291 may include a coil and a resonant circuit that generate a resonance phenomenon by a magnetic field having a specific resonance frequency as a component according to a resonant coupling scheme.

However, when the power receiving unit 291 receives power according to one or more wireless power transmission schemes, the power receiving unit 291 may be configured to receive using one coil, And may be implemented to receive using a coil.

Among the elements included in the power receiving unit 291, those following the inductive coupling scheme will be described with reference to FIGS. 4A and 4B, and the ones according to the resonant coupling scheme will be described later with reference to FIG.

Meanwhile, the power receiving unit 291 may further include a rectifier and a regulator for converting the radio power signal into a direct current. The power receiving unit 291 may further include a circuit for preventing an overvoltage or an overcurrent from occurring due to the received power signal.

The power reception control unit 292 controls the components included in the power supply unit 290.

Specifically, the power receiving control unit 292 may transmit a power control message to the wireless power transmission apparatus 100. FIG. The power control message may instruct the wireless power transmission apparatus 100 to start or terminate the transmission of the wireless power signal. The power control message may also direct the wireless power transmission apparatus 100 to adjust the characteristics of the wireless power signal.

In order to transmit the power control message, the power control unit 292 may use at least one of a method of transmitting through the wireless power signal and a method of transmitting through the other user data.

In order to transmit the power control message, the wireless power receiving apparatus 200 may further include a power communication modulation / demodulation unit 293 electrically connected to the power receiving unit 291. The modem unit 293 can be used to transmit the power control message through the wireless power signal, as in the case of the wireless power transmission apparatus 100 described above. The modem unit 293 may be used as a means for adjusting the current and / or voltage flowing through the power conversion unit 111 of the wireless power transmission apparatus 100. Hereinafter, a description will be given of a method in which the modulation and demodulation units 113 and 293 of the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 are used for transmission and reception of a power control message through a wireless power signal, respectively do.

The wireless power signal formed by the power conversion unit 111 is received by the power receiving unit 291. At this time, the power reception control unit 292 controls the modem unit 293 of the wireless power receiving apparatus 200 to modulate the wireless power signal. For example, the power reception control unit 292 may modify the reactance of the modem unit 293 connected to the power reception unit 291 so that the amount of power received from the wireless power signal changes accordingly have. A change in the amount of power received from the wireless power signal results in a change in the current and / or voltage of the power conversion unit 111 forming the wireless power signal. At this time, the modulation / demodulation unit 113 of the wireless power transmission apparatus 100 detects a change in the current and / or voltage of the power conversion unit 111 and performs a demodulation process.

That is, the power reception controller 292 generates a packet including a power control message to be transmitted to the wireless power transmission apparatus 100, modulates the wireless power signal to include the packet, The transmission control unit 112 can obtain the power control message included in the packet by decoding the packet based on the demodulation process result of the modulation / demodulation unit 113.

In addition, in some embodiments, the power reception control unit 292 transmits user data including a power control message by communication means (not shown) included in the wireless power reception apparatus 200, To the wireless power transmission apparatus 100. The wireless power transmission apparatus 100 shown in FIG.

[When supporting in-band two-way communication]

In addition, in the wireless power transmission environment capable of bidirectional communication according to the embodiments disclosed herein, the power reception control unit 292 can receive data transmitted from the wireless power transmission apparatus 100. [ The data transmitted from the wireless power transmission apparatus 100 may be to request to transmit a power control message.

In addition, the power supply unit 290 may be configured to further include a charging unit 298 and a battery 299.

The wireless power receiving apparatus 200 receiving power for operation from the power supply unit 290 operates by the power transmitted from the wireless power transmission apparatus 100 or by using the transmitted power, The battery 299 can be operated by the electric power charged in the battery 299 after the battery 299 is charged. At this time, the power receiving control unit 292 may control the charging unit 298 to perform charging using the transmitted power.

Hereinafter, a wireless power transmission apparatus and a wireless power receiving apparatus applicable to the embodiments disclosed herein will be described. 3 to 5, a method of transmitting power by the wireless power transmission apparatus to the wireless power reception apparatus according to an inductive coupling scheme is disclosed.

Inductively coupled

3 illustrates a concept that power is transmitted from a wireless power transmission apparatus to a wireless power receiving apparatus wirelessly according to an inductive coupling scheme.

When the power transmission of the wireless power transmission apparatus 100 follows the inductive coupling scheme, when the intensity of the current flowing through the primary coil in the power transmission unit 110 is changed, the primary coil The passing magnetic field changes. The thus changed magnetic field generates an induced electromotive force on the secondary coil side of the wireless power receiving apparatus 200.

According to this scheme, the power conversion section 111 of the wireless power transmission apparatus 100 is configured to include a transmission coil (Tx coil) 1111a that operates as a primary coil in magnetic induction. The power receiving unit 291 of the wireless power receiving apparatus 200 is configured to include a receiving coil (Rx coil) 2911a that operates as a secondary coil in magnetic induction.

The wireless power transmission apparatus 100 and the wireless power receiving apparatus 200 are arranged such that the transmission coil 1111a on the wireless power transmission apparatus 100 side and the reception coils on the wireless power reception apparatus 200 side are close to each other, . Thereafter, when the power transmission control unit 112 controls the current of the transmission coil 1111a to be changed, the power receiving unit 291 receives the power from the wireless power receiving apparatus 200 to be supplied with power.

The efficiency of the wireless power transmission by the inductively coupled system is less influenced by the frequency characteristics but is influenced by the alignment between the wireless power transmission apparatus 100 including the coils and the wireless power reception apparatus 200, And distance (distance).

Meanwhile, the wireless power transmission apparatus 100 may be configured to include an interface surface (not shown) in the form of a flat surface for wireless power transmission by the inductive coupling method. One or more wireless power receiving devices may be disposed on the interface surface, and the transmission coil 1111a may be mounted on a lower surface of the interface. In this case, the vertical spacing between the transmission coil 1111a mounted on the lower surface of the interface and the reception coil 2911a of the wireless power receiving apparatus 200 located above the interface surface is made small The distance between the coils is sufficiently small so that wireless power transmission by the inductive coupling method can be efficiently performed.

In addition, an arrangement indicator (not shown) may be formed on the interface surface to indicate a position where the wireless power receiving apparatus 200 is to be placed. The arrangement indicator indicates the position of the wireless power receiving apparatus 200 in which the arrangement between the transmission coil 1111a mounted on the lower surface of the interface and the reception coil 2911a can be suitably adjusted. The arrangement indicator may be a simple mark or may be formed in the form of a protruding structure for guiding the position of the wireless power receiving apparatus 200. Or the array directing part is formed in the form of a magnetic body such as a magnet mounted on the lower surface of the interface so that the coils are arranged in an appropriate array by mutual attracting force with other magnetic bodies mounted inside the wireless power receiving apparatus 200 As shown in FIG.

Meanwhile, the wireless power transmission apparatus 100 may be formed to include one or more transmission coils. The wireless power transmission apparatus 100 may selectively increase the power transmission efficiency by selectively using a part of the coils suitably arranged with the reception coil 2911a of the wireless power reception apparatus 200 among the one or more transmission coils. The wireless power transmission apparatus 100 including the one or more transmission coils will be described below with reference to Fig.

Hereinafter, a configuration of an inductively coupled wireless power transmission apparatus and a wireless power reception apparatus applicable to the embodiments disclosed herein will be described in detail.

Inductively coupled wireless power transmission apparatus and wireless power receiving apparatus

4A and 4B are block diagrams illustrating a portion of the configuration of a wireless power transmission apparatus 100 and a wireless power reception apparatus 200 of a magnetic induction type that can be employed in the embodiments disclosed herein. 4A, the configuration of the power transfer unit 110 included in the wireless power transmission apparatus 100 will be described. Referring to FIG. 4B, the configuration of the power supply unit 110 included in the wireless power reception apparatus 200 will be described. 290 will be described.

Referring to FIG. 4A, the power conversion unit 111 of the wireless power transmission apparatus 100 may be configured to include a transmission coil (Tx coil) 1111a and an inverter 1112. FIG.

As described above, the transmission coil 1111a forms a magnetic field corresponding to a radio power signal in accordance with a change in current. The transmission coil 1111a may be implemented as a planar spiral type or a cylindrical solenoid type.

The inverter 1112 transforms a DC input obtained from the power supply unit 190 into an AC waveform. An alternating current deformed by the inverter 1112 is formed in the transmission coil 1111a by driving a resonant circuit including the transmission coil 1111a and a capacitor (not shown) .

In addition, the power conversion unit 111 may be further configured to include a positioning unit 1114.

The positioning unit 1114 may move or rotate the transmission coil 1111a to increase the efficiency of the wireless power transmission by the inductive coupling scheme. This is because, as described above, the power transmission by the inductively coupled mode is performed by adjusting the alignment and distance between the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 including the primary and secondary coils distance). Particularly, the positioning unit 1114 can be used when the wireless power receiving apparatus 200 is not in the active area of the wireless power transmission apparatus 100.

The position determining unit 1114 determines that the distance between the center of the transmission coil 1111a of the wireless power transmission apparatus 100 and the center of the reception coil 2911a of the wireless power reception apparatus 200 is (Not shown) that moves the transmission coil 1111a so as to be within a certain range or rotates the transmission coil 1111a so that the center of the transmission coil 1111a and the reception coil 2911a overlap with each other .

To this end, the wireless power transmission apparatus 100 may further include a position detection unit (not shown) configured to detect a position of the wireless power reception apparatus 200, The controller 112 may control the positioning unit 1114 based on the position information of the wireless power receiving apparatus 200 received from the position sensing sensor.

For this, the power transmission control unit 112 receives control information on the arrangement or distance with the wireless power receiving apparatus 200 through the modulation / demodulation unit 113, and transmits control information on the received arrangement or distance The position determining unit 1114 can be controlled based on the position information.

If the power conversion unit 111 is configured to include a plurality of transmission coils, the positioning unit 1114 can determine which of the plurality of transmission coils is to be used for power transmission. The configuration of the wireless power transmission apparatus 100 including the plurality of transmission coils will be described later with reference to Fig.

Meanwhile, the power conversion unit 111 may be configured to further include a power sensing unit 1115. The power sensing unit 1115 on the side of the wireless power transmission apparatus 100 monitors the current or voltage flowing in the transmission coil 1111a. The power sensing unit 1115 detects a voltage or current of a power source supplied from outside and determines whether the detected voltage or current exceeds a threshold value Can be confirmed. The power sensing unit 1115 compares a voltage or current value of the detected power source with a threshold value and outputs a result of the comparison. And a comparator. Based on the result of the detection by the power sensing unit 1115, the power transmission control unit 112 may control the switching unit (not shown) to cut off the power applied to the transmission coil 1111a.

Referring to FIG. 4B, the power supply unit 290 of the wireless power receiving apparatus 200 may be configured to include a receiving coil (Rx coil) 2911a and a rectifying circuit 2913.

A current is induced in the reception coil 2911a by a change in the magnetic field formed from the transmission coil 1111a. The receiving coil 2911a may be in the form of a flat spiral or cylindrical solenoid, as in the case of the transmitting coil 1111a.

In addition, series and parallel capacitors may be connected to the receiving coil 2911a to enhance reception efficiency of the wireless power or to detect resonance.

The receiving coil 2911a may be in the form of a single coil or a plurality of coils.

The rectifying circuit 2913 performs full-wave rectification on the current to convert the alternating current into direct current. The rectifier circuit 2913 may be implemented by, for example, a full bridge rectifier circuit including four diodes or a circuit using active components.

In addition, the rectifying circuit 2913 may further include a regulator for converting the rectified current into a more flat and stable direct current. The output power of the rectifying circuit 2913 is supplied to the respective components of the power supply unit 290. The rectifying circuit 2913 is a DC-DC converter that converts the output DC power to an appropriate voltage to match the power required for each component of the power supply unit 290 (for example, a circuit similar to the charging unit 298) (DC-DC converter).

The modulation and demodulation unit 293 may be constituted by a resistive element connected to the power receiving unit 291 and having a resistance varying with respect to a direct current and a capacitive element whose reactance is changed with respect to an alternating current . The power receiving control unit 292 may modulate the wireless power signal received by the power receiving unit 291 by changing the resistance or reactance of the modem unit 293.

The power supply unit 290 may further include a power sensing unit 2914. The power sensing unit 2914 of the wireless power receiving apparatus 200 monitors the voltage and / or the current of the power source rectified by the rectifying circuit 2913 and monitors the voltage and / or current of the rectified power source When the current exceeds the threshold value, the power receiving control unit 292 transmits a power control message to the wireless power transmission apparatus 100 to transmit appropriate power.

A wireless power transmission apparatus configured with one or more transmission coils

5 is a block diagram of a wireless power transmission apparatus configured to have one or more transmission coils that receive power in accordance with an inductive coupling scheme employable in the embodiments disclosed herein.

Referring to FIG. 5, the power conversion section 111 of the wireless power transmission apparatus 100 according to the embodiments disclosed herein may be configured with one or more transmission coils 1111a-1 to 1111a-n. The one or more transmission coils 1111a-1 to 1111a-n may be an array of partly overlapping primary coils. An active area may be determined by a portion of the one or more transmission coils.

The one or more transmission coils 1111a-1 to 1111a-n may be mounted below the interface surface. The power conversion unit 111 may further include a multiplexer 1113 for establishing and releasing connection of some of the one or more transmission coils 1111a-1 to 1111a-n .

When the position of the wireless power receiving apparatus 200 located on the interface surface is sensed, the power transmission control unit 112 controls the transmission power of the one or more transmission coils 1111a-1 to 1111a-n of the wireless power receiving apparatus 200 can be connected to the receiving coils 2911a of the wireless power receiving apparatus 200. [

For this, the power transmission control unit 112 may acquire the location information of the wireless power receiving apparatus 200. For example, the power transmission control unit 112 acquires the position of the wireless power receiving apparatus 200 on the interface surface by the position sensing unit (not shown) provided in the wireless power transmission apparatus 100 . As another example, the power transmission control unit 112 may use the one or more transmission coils 1111a-1 to 1111a-n to generate a power control message indicating the strength of the wireless power signal from an object on the interface surface, Acquiring position information of the wireless power receiving apparatus 200 by receiving a power control message indicating identification information of the object and determining which coil of the one or more transmission coils is close to the position based on the received result, You may.

On the other hand, the active area is a part of the interface surface, which means that the high efficiency magnetic field can pass when the wireless power transmission apparatus 100 transmits power wirelessly to the wireless power receiving apparatus 200 . At this time, a single transmission coil or a combination of one or more transmission coils for forming a magnetic field passing through the active region may be referred to as a primary cell. Therefore, the power transmission control unit 112 determines an activity area based on the sensed position of the wireless power receiving apparatus 200, establishes connection of major cells corresponding to the active area, 200 and the coils belonging to the main cell can be placed in the inductive coupling relationship with each other.

The power conversion unit 111 may further include an impedance matching unit (not shown) for adjusting the impedance to form a resonant circuit with the coils connected thereto.

Hereinafter, a method of transmitting power according to a resonant coupling scheme by a wireless power transmission apparatus is described with reference to FIGS.

Resonance coupling method

FIG. 6 illustrates a concept that power is transmitted from a wireless power transmission apparatus to a wireless power reception apparatus wirelessly according to a resonant coupling scheme.

First, the resonance (or resonance) will be briefly described as follows. Resonance refers to a phenomenon in which the vibration system receives an external force periodically having the same frequency as its natural frequency, and the amplitude thereof increases sharply. Resonance is a phenomenon occurring in all vibrations, such as mechanical vibration and electrical vibration. Generally, when a force capable of vibrating the vibration system is applied from the outside, if the natural frequency of the vibration system is equal to the frequency of the external force, the vibration becomes larger and the amplitude becomes larger.

In the same principle, when a plurality of vibrating bodies separated within a certain distance oscillate at the same frequency, the plurality of vibrating bodies resonate with each other, and in this case, the resistance between the vibrating bodies decreases. In an electric circuit, an inductor and a capacitor can be used to make a resonant circuit.

When the power transmission of the wireless power transmission apparatus 100 follows the resonant coupling scheme, a magnetic field having a specific vibration frequency is formed by the AC power source in the power transmission unit 110. When a resonance phenomenon occurs in the wireless power receiving apparatus 200 due to the magnetic field, power is generated in the wireless power receiving apparatus 200 by the resonance phenomenon.

The resonance frequency can be determined by, for example, the following equation (1).

[Equation 1]

Here, the resonance frequency f is determined by the inductance L and the capacitance C in the circuit. In a circuit for forming a magnetic field using a coil, the inductance is determined by the number of revolutions of the coil and the like, and the capacitance can be determined by an interval, an area, or the like between the coils. A capacitive resonance circuit may be connected to the coil to determine the resonance frequency.

Referring to FIG. 6, when power is transmitted wirelessly according to a resonant coupling scheme, the power conversion unit 111 of the wireless power transmission apparatus 100 includes a transmission coil (Tx coil) 1111b and a transmission coil And a resonance circuit 1116 connected to the transmission coil 1111b and for determining a specific oscillation frequency. The resonant circuit 1116 can be implemented using capacitors and the specific oscillation frequency is determined based on the inductance of the transmission coil 1111b and the capacitance of the resonant circuit 1116. [

The configuration of the circuit elements of the resonant circuit 1116 may be variously configured to form a magnetic field by the power conversion unit 111 and may be connected in parallel with the transmission coil 1111b as shown in FIG. It is not limited.

The power receiving unit 291 of the wireless power receiving apparatus 200 further includes a resonant circuit 2912 and a receiving coil Rx coil configured to cause a resonance phenomenon by a magnetic field formed in the wireless power transmission apparatus 100, Gt; 2911b. ≪ / RTI > That is, the resonance circuit 2912 may be implemented using a capacitive circuit, and the resonance circuit 2912 is determined based on the inductance of the reception coil 2911b and the capacitance of the resonance circuit 2912 And the resonance frequency is equal to the resonance frequency of the magnetic field formed.

 The configuration of the circuit elements of the resonant circuit 2912 may be variously configured to allow the power receiving unit 291 to resonate by the magnetic field and may be connected in series with the receiving coil 2911b as shown in FIG. But is not limited to.

The specific vibration frequency in the wireless power transmission apparatus 100 may be obtained using Equation 1 with LTx, CTx. Here, resonance occurs in the wireless power receiving apparatus 200 when the result of substituting the LRX and CRX of the wireless power receiving apparatus 200 into Equation 1 is equal to the specific vibration frequency.

According to the wireless power transmission scheme using the resonance coupling, when the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 resonate at the same frequency, the electromagnetic waves are transmitted through the near field electromagnetic field, There is no energy transfer between devices.

Therefore, the efficiency of the wireless power transmission by the resonance coupling method is largely affected by the frequency characteristics, while the arrangement between the wireless power transmission apparatus 100 including the coils and the wireless power reception apparatus 200, The effect of distance is relatively small compared to inductive coupling.

Hereinafter, a configuration of a wireless power transmission apparatus and a wireless power reception apparatus of a resonance coupling type applicable to the embodiments disclosed herein will be described in detail.

Resonant coupling type wireless power transmission device

7 is a block diagram exemplarily showing a part of the configuration of the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 of the resonance type that can be employed in the embodiments disclosed herein.

The configuration of the power transmission unit 110 included in the wireless power transmission apparatus 100 will be described with reference to FIG. 7A.

The power conversion unit 111 of the wireless power transmission apparatus 100 may be configured to include a transmission coil (Tx coil) 1111b, an inverter 1112, and a resonant circuit 1116. [ The inverter 1112 may be configured to be connected to the transmission coil 1111b and the resonant circuit 1116.

The transmission coil 1111b may be mounted separately from the transmission coil 1111a for transmitting electric power according to the inductive coupling scheme, but it may also transmit power using an inductive coupling scheme or a resonant coupling scheme using one single coil.

The transmission coil 1111b forms a magnetic field for transmitting electric power, as described above. The transmission coil 1111b and the resonant circuit 1116 may be vibrated when the AC power is applied and at this time the oscillation frequency is set to a value based on the inductance of the transmission coil 1111b and the capacitance of the resonant circuit 1116 Can be determined.

To this end, the inverter 1112 transforms a DC input obtained from the power supply unit 190 into an AC waveform, and the transformed AC current is applied to the transmission coil 1111b and the resonance circuit 1116.

In addition, the power conversion unit 111 may further include a frequency adjustment unit 1117 for changing the resonance frequency value of the power conversion unit 111. Since the resonance frequency of the power conversion unit 111 is determined based on the inductance and the capacitance in the circuit constituting the power conversion unit 111 according to Equation 1, the power transmission control unit 112 controls the inductance and / The resonance frequency of the power converter 111 can be determined by controlling the frequency adjuster 1117 so that the capacitance is changed.

The frequency adjuster 1117 may include a motor capable of changing the capacitance by adjusting the distance between the capacitors included in the resonant circuit 1116 or may include a motor for changing the number of rotations of the transmission coil 1111b number of turns, or a motor capable of changing the inductance by adjusting the diameter, or it may be configured to include active elements that determine the capacitance and / or inductance.

Meanwhile, the power conversion unit 111 may be configured to further include a power sensing unit 1115. The operation of the power sensing unit 1115 is the same as described above.

The configuration of the power supply unit 290 included in the wireless power receiving apparatus 200 will be described with reference to FIG. 7B. The power supply 290 may be configured to include the receive coil (Rx coil) 2911b and the resonant circuit 2912, as described above.

In addition, the power receiving unit 291 of the power supply unit 290 may be configured to further include a rectifying circuit 2913 that converts the alternating current generated by the resonance phenomenon to direct current. The rectifying circuit 2913 may be constructed in the same manner as described above.

The power receiving unit 291 may further include a power sensing unit 2914 for monitoring the voltage and / or current of the rectified power. The power sensing unit 2914 may be configured as described above.

A wireless power transmission apparatus configured with one or more transmission coils

8 is a block diagram of a wireless power transmission apparatus configured to have one or more transmission coils that receive power in accordance with a resonant coupling scheme employable in the embodiments disclosed herein.

8, the power conversion section 111 of the wireless power transmission apparatus 100 according to the embodiments disclosed herein includes one or more transmission coils 1111b-1 to 1111b-n and a plurality of transmission coils And may be configured to include resonant circuits 1116-1 through 1116-n. The power conversion unit 111 may further include a multiplexer 1113 for establishing and releasing a connection of some of the one or more transmission coils 1111b-1 to 1111b-n .

The one or more transmission coils 1111b-1 to 1111b-n may be set to have the same resonance frequency, or may be set so that some have different resonance frequencies. Which is determined according to what inductance and / or capacitance the resonant circuits 1116-1 through 1116-n respectively connected to the one or more transmission coils 1111b-1 through 1111b-n have.

The frequency adjuster 1117 may change the inductance and / or capacitance of the resonant circuits 1116-1 through 1116-n connected to the one or more transmission coils 1111b-1 through 1111b-n, Or < / RTI >

In - band communication

9 illustrates a concept of transmitting and receiving packets between a wireless power transmission device and an electronic device through modulation and demodulation of a wireless power signal in wireless power transmission according to the embodiments disclosed herein.

Referring to FIG. 9, the power conversion unit 111 included in the wireless power transmission apparatus 100 forms a wireless power signal. The wireless power signal is formed through a transmission coil 1111 included in the power conversion unit 111.

The wireless power signal 10a formed by the power conversion unit 111 reaches the electronic device 200 and is received through the power receiving unit 291 included in the electronic device 200. [ The generated radio power signal is received through a receiving coil 2911 included in the power receiving unit 291.

The power reception control unit 292 controls the modulation / demodulation unit 293 connected to the power reception unit 291 to modulate the wireless power signal while the electronic device 200 receives the wireless power signal . When the received wireless power signal is modulated, the wireless power signal forms a closed-loop within a magnetic field or an electro-magnetic field, When modulating the wireless power signal while receiving a power signal, the wireless power transmission apparatus 100 may sense the modulated wireless power signal 10b. Demodulation unit 113 demodulates the detected radio power signal and decodes the packet from the demodulated radio power signal.

Meanwhile, a modulation method used for communication between the wireless power transmission apparatus 100 and the electronic device 200 may be amplitude modulation. As described above, in the amplitude modulation method, the modulation / demodulation unit 293 of the electronic device 200 side changes the amplitude of the wireless power signal 10a formed by the power conversion unit 111, The modulation and demodulation unit 293 of the base station 100 may be a backscatter modulation method for detecting the amplitude of the modulated radio power signal 10b.

Modulation and demodulation of wireless power signals

Modulation and demodulation of packets transmitted and received between the wireless power transmission apparatus 100 and the electronic apparatus 200 will be described below with reference to FIGS. 10 and 11. FIG.

10 illustrates a configuration for transmitting and receiving a power control message in a wireless power transmission according to the embodiments disclosed herein. FIG. 11 illustrates the form of signals in modulation and demodulation performed in a wireless power transmission in accordance with the embodiments disclosed herein.

Referring to FIG. 10, a wireless power signal received through the power receiving unit 291 on the electronic device 200 side is a wireless power signal 51 that is not modulated as shown in FIG. 11 (a). Resonance coupling is performed between the electronic device 200 and the wireless power transmission apparatus 100 according to the resonance frequency set by the resonance forming circuit 2912 in the power receiving unit 291 and the resonance frequency of the receiving coil 2911b The wireless power signal 51 is received.

The power reception control unit 292 modulates the wireless power signal 51 received through the power reception unit 291 by changing the load impedance in the modem unit 293. The modulation and demodulation unit 293 may be configured to include a passive element 2931 and an active element 2932 for modulating the wireless power signal 51. [ The modem unit 293 modulates the wireless power signal 51 to include a packet to be transmitted to the wireless power transmission apparatus 100. At this time, the packet may be input to the active element 2932 in the modem unit 293.

Thereafter, the power transmission control unit 112 of the wireless power transmission apparatus 100 demodulates the modulated wireless power signal 52 through an envelope detection process, and transmits the detected signal 53 And decodes it into digital data 54. The demodulation process detects that a current or a voltage flowing through the power conversion unit 111 is divided into two states according to a modulated wireless power signal, that is, a HI state and an LO state, The electronic device 200 obtains a packet to be transmitted by the electronic device 200 based on the digital data classified according to the type of the digital data.

Hereinafter, a process of acquiring the power control message to be transmitted by the electronic device 200 from the digital data demodulated by the wireless power transmission apparatus 100 will be described.

Referring to FIG. 11 (b), the power transmission control unit 112 detects an encoded bit using a clock signal CLK from an envelope-detected signal. The detected encoded bits are encoded according to the bit encoding method used in the modulation process on the electronic device 200 side. In some embodiments, the bit encoding method may be NRZ (non-return to zero). In some embodiments, the bit encoding method may be bi-phase encoding.

For example, in some embodiments, the detected bits may be differential bi-phase (DBP) encoded. According to the DBP encoding, the power reception control unit 292 of the electronic device 200 has two state transitions to encode the data bit 1, and one state transition to encode the data bit 0, . That is, the data bit 1 is encoded such that the transition between the HI state and the LO state occurs at the rising edge and the falling edge of the clock signal, and the data bit 0 is at the rising edge of HI State and the LO state may be encoded to occur.

On the other hand, the power transmission control unit 112 can obtain data in units of bytes by using a byte format that forms a packet from the bit stream detected according to the bit encoding method. In some embodiments, the detected bit stream may be transmitted using an 11-bit asynchronous serial format as shown in FIG. 11 (c). That is, it may include a start bit indicating the start of the byte and a stop bit indicating the end, and may include data bits (b0 through b7) between the start bit and the end bit. In addition, a parity bit for checking the error of the data may be added. The byte-by-byte data constitutes a packet including a power control message.

[When in-band two-way communication is supported]

Although the wireless power receiving apparatus 200 shown in FIG. 9 transmits a packet using a carrier signal 10a formed by the wireless power transmission apparatus 100, The device 100 may also transmit data to the wireless power receiving device 200 in a similar manner.

That is, the power transmission control unit 112 may control the modulation / demodulation unit 113 to modulate the data to be sent to the wireless power reception apparatus 200 to be written on the carrier signal 10a. In this case, the demodulation unit 293 is controlled to demodulate the power reception control unit 292 of the wireless power receiving apparatus 200 so that the power reception control unit 292 can acquire data from the modulated carrier signal 10a .

Packet format

Hereinafter, the structure of a packet used in communication using a wireless power signal according to the embodiments disclosed herein will be described.

12 illustrates a packet including a power control message used in a wireless power transfer method in accordance with the embodiments disclosed herein.

Referring to FIG. 12 (a), the wireless power transmission apparatus 100 and the electronic device 200 can transmit and receive data to be transmitted in the form of a command packet (command packet) 510. The command packet 510 may be configured to include a header 511 and a message 512.

The header 511 may include a field indicating a type of data included in the message 512. The size and type of the message can be determined based on a value indicated by a field indicating the type of the data.

In addition, the header 511 may include an address field for identifying a sender of the packet. For example, the address field may indicate an identifier of the electronic device 200 or an identifier of a group to which the electronic device 200 belongs. When the electronic device 200 wants to transmit the packet 510, the electronic device 200 generates the packet 510 so that the address field of the packet 510 indicates its own identification information can do.

The message 512 includes data that the sender of the packet 510 wants to transmit. The data included in the message 512 may be a report, a request, or a response to the other party.

Meanwhile, in some embodiments, the instruction packet 510 may be configured as shown in FIG. 12 (b). The header 511 included in the command packet 510 may be represented by a predetermined size. For example, the header 511 may be two bytes in size.

The header 511 may be configured to include a destination address field. For example, the destination address field may be six bits in size.

The header 511 may be configured to include an operation command field (OCF) or an operation group field (OGF). OGF is a value assigned to each group of commands for the electronic device 200 and OCF is a value assigned to each command included in each group including the electronic device 200. [

The message 512 may be divided into a parameter length field 5121 and a parameter value field 5122. That is, the sender of the packet 510 may configure the message in the form of length-value pairs (5121a-5122a, etc.) of one or more parameters required to express the data to be transmitted.

12C, the wireless power transmission apparatus 100 and the electronic apparatus 200 may transmit a packet having the preamble 520 and the checksum 530 added thereto for transmission in the command packet 510 And the data can be transmitted and received in the form of the data.

The preamble 520 is used for the wireless power transmission apparatus 100 to perform synchronization with data to be received and to accurately detect the start bit of the command packet 510. The preamble 520 may be configured to repeat the same bit. For example, the preamble 520 may be configured such that the data bit 1 according to the DBP encoding is repeated 11 to 25 times.

The checksum 530 is used to detect an error that may occur in the command packet 510 during the transmission of the power control message.

Operation status ( Phases )

Hereinafter, the operation states of the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 will be described.

13 illustrates operating states of a wireless power transmission apparatus 100 and a wireless power receiving apparatus 200 according to embodiments disclosed herein. 14 to 18 show the structure of packets including a power control message between the wireless power transmission apparatus 100 and the wireless power reception apparatus 200. [

13, the operation states of the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 for wireless power transmission are a Selection Phase 610, a Ping Phase 620, An Identification and Configuration Phase 630, and a Power Transfer Phase 640.

In the selected state 610, it is detected whether or not objects exist within a range where the wireless power transmission apparatus 100 can wirelessly transmit power. In the detection state 620, the wireless power transmission apparatus 100 100 sends a detection signal to the sensed object, and the wireless power receiving apparatus 200 sends a response to the detection signal.

Also, in the identification and setting state 630, the wireless power transmission apparatus 100 identifies the selected wireless power receiving apparatus 200 through the previous states and acquires setting information for power transmission. In the power transmission state 640, the wireless power transmission apparatus 100 adjusts power to be transmitted in response to a control message received from the wireless power reception apparatus 200, And transmits power.

Hereinafter, the respective operation states will be described in detail.

1) Selection status ( Selection Phase )

The wireless power transmission apparatus 100 in the selected state 610 performs a detection process to select the wireless power receiving apparatus 200 existing in the sensing area. As described above, the sensing area refers to an area where an object in the area can affect the characteristics of the power of the power conversion part 111. [ The detection process for selecting the wireless power receiving apparatus 200 in the selected state 610, as compared with the detection state 620, receives a response from the wireless power receiving apparatus 200 using the power control message The power conversion unit of the wireless power transmission apparatus 100 detects a change in the amount of power for forming a wireless power signal and determines whether an object exists within a predetermined range. The detection process in the selected state 610 may be referred to as an analog detection process (analog ping) in that an object is detected using a wireless power signal without using a digital format packet in a detection state 620 to be described later .

The wireless power transmission apparatus 100 in the selected state 610 can sense that an object enters and exits the sensing area. In addition, the wireless power transmission apparatus 100 may distinguish the wireless power receiving apparatus 200 and other objects (e.g., keys, coins, etc.) capable of wirelessly transmitting power among objects in the sensing area .

As described above, since the distance over which the electric power can be transmitted wirelessly differs according to the inductive coupling method and the resonant coupling method, the sensing area where the object is detected in the selected state 610 may be different from each other.

First, when power is transmitted according to the inductive coupling scheme, the wireless power transmission apparatus 100 of the selected state 610 may monitor the interface surface (not shown) to detect placement and removal of objects.

In addition, the wireless power transmission apparatus 100 may sense the position of the wireless power receiving apparatus 200 placed on the interface surface. As described above, the wireless power transmission apparatus 100 formed to include one or more transmission coils enters the detection state 620 in the selected state 610 and uses each coil in the detection state 620 A method for confirming whether or not a response to the detection signal is transmitted from the object, or thereafter entering the identification state 630 and checking whether the identification information is transmitted from the object. The wireless power transmission apparatus 100 may determine a coil to be used for wireless power transmission based on the position of the sensed wireless power receiving apparatus 200 acquired through the above process.

In addition, when power is transmitted according to the resonant coupling scheme, the wireless power transmission apparatus 100 in the selected state 610 changes one or more of frequency, current, and voltage of the power conversion unit due to an object in the sensing area It is possible to detect the object.

Meanwhile, the wireless power transmission apparatus 100 in the selected state 610 can detect an object by at least one of the inductive coupling method and the resonant coupling method detection method. The wireless power transmission apparatus 100 performs an object detection process according to each power transmission method and then detects the object among the combining methods for wireless power transmission in order to proceed to other states 620, 630, and 640 You can choose one method.

On the other hand, the wireless power transmission apparatus 100 in the selected state 610 can detect a wireless power signal to detect an object and digital detection, identification, setting, and power transmission in the following states 620, 630, and 640 The characteristics of the wireless power signal, such as frequency, intensity, etc., may be different. This is because the selected state 610 of the wireless power transmission apparatus 100 corresponds to an idle phase for detecting an object so that the wireless power transmission apparatus 100 can reduce power consumption in the air, So that it is possible to generate a specialized signal for object detection.

2) Detection status ( Ping Phase )

The wireless power transmission apparatus 100 in the detection state 620 detects a wireless power reception apparatus 200 existing in the sensing area through a power control message. In comparison with the detection process of the wireless power receiving apparatus 200 using the characteristics of the wireless power signal in the selected state 610, the detection process in the detection state 620 may be referred to as digital ping have.

In the detection state 620, the wireless power transmission apparatus 100 forms a wireless power signal for detecting the wireless power receiving apparatus 200, and transmits the wireless power signal modulated by the wireless power receiving apparatus 200 And obtains a power control message in the form of digital data corresponding to the response to the detection signal from the demodulated radio power signal. The wireless power transmission apparatus 100 can recognize the wireless power receiving apparatus 200 that is a target of power transmission by receiving a power control message corresponding to a response to the detection signal.

The detection signal formed by the wireless power transmission apparatus 100 in the detection state 620 to perform the digital detection process is a wireless power signal generated by applying a power signal of a specific operating point for a predetermined time . The operating point may refer to a frequency, a duty cycle and an amplitude of a voltage applied to the Tx coil. The wireless power transmission apparatus 100 may generate the detection signal generated by applying the power signal of the specific operating point for a certain period of time and attempt to receive a power control message from the wireless power receiving apparatus 200 have.

Meanwhile, the power control message corresponding to the response to the detection signal may be a message indicating the strength of the wireless power signal received by the wireless power receiving apparatus 200. For example, the wireless power receiving apparatus 200 may include a signal strength packet 5100 including a message indicating the strength of a received wireless power signal as a response to the detection signal as shown in FIG. 14 Can be transmitted. The packet 5100 may be configured to include a header 5120 indicating that the packet is a packet indicating the signal strength and a message 5130 indicating the strength of the power signal received by the wireless power receiving apparatus 200. The strength of the power signal in the message 5130 may be a value indicative of the degree of coupling of inductive coupling or resonant coupling for power transmission between the wireless power transmission apparatus 100 and the wireless power receiving apparatus 200 have.

After receiving the response message to the detection signal and finding the wireless power receiving apparatus 200, the wireless power transmission apparatus 100 may extend the digital detection process to enter the identification and detection state 630 have. That is, the wireless power transmission apparatus 100 can receive the power control message in the identification and detection state 630 by maintaining the power signal of the specific operating point after finding the wireless power receiving apparatus 200 have.

However, if the wireless power transmission apparatus 100 does not find a wireless power receiving apparatus 200 capable of transmitting electric power, the operation state of the wireless power transmission apparatus 100 returns to the selected state 610 .

3) Identification and setting status ( Identification and Configuration Phase )

The wireless power transmission apparatus 100 in the identification and setting state 630 can receive the identification information and / or the setting information transmitted by the wireless power receiving apparatus 200 and control the power transmission to be performed efficiently.

In the identifying and setting state 630, the wireless power receiving apparatus 200 may transmit a power control message including its identification information. For this purpose, the wireless power receiving apparatus 200 can transmit an identification packet (Identification Packet) 5200 including a message indicating the identification information of the wireless power receiving apparatus 200, for example, as shown in FIG. 15A have. The packet 5200 may be configured to include a header 5220 indicating that it is a packet indicating identification information, and a message 5230 including identification information of the wireless power receiving apparatus. The message 5230 includes information 2531 and 5232 indicating a version of a protocol for wireless power transmission, information 5233 identifying a manufacturer of the wireless power receiving apparatus 200, information indicating the presence or absence of an extension device identifier A base station identifier 5234 and a base unit identifier 5235. [ In addition, when it is indicated that the extension device identifier exists in the information 5234 indicating the presence or absence of the extension device identifier, an Extended Identification Packet 5300 including the extension device identifier as shown in FIG. 15B Can be transmitted separately. The packet 5300 may be configured to include a header 5320 indicating that the packet is an extension device identifier, and a message 5330 including an extension device identifier. When the extension device identifier is used as described above, it is possible to identify the wireless power receiving apparatus 200 based on the identification information 5233 of the manufacturer, the base unit identifier 5235 and the extension unit identifier 5330 Information can be used.

In the identifying and setting state 630, the wireless power receiving apparatus 200 may transmit a power control message including information on the estimated maximum power. For this purpose, the wireless power receiving apparatus 200 can transmit, for example, a configuration packet (Configuration Packet) 5400 as shown in FIG. The packet may be configured to include a header 5420 indicating that it is a configuration packet and a message 5430 containing information on the expected maximum power. The message 5430 includes a power class 5431, information 5432 about the expected maximum power, an indicator 5433 indicating how to determine the current of the primary cell on the wireless power transmission side, 5434). The indicator 5433 may indicate whether or not the current of the main cell of the wireless power transmission apparatus side is to be determined as specified in the protocol for wireless power transmission.

Meanwhile, the wireless power transmission apparatus 100 may generate a power transfer contract to be used for power charging with the wireless power reception apparatus 200 based on the identification information and / or the setting information. The power transfer protocol may include limits of parameters that determine the power transfer characteristics in the power transfer state 640. [

The wireless power transmission apparatus 100 may terminate the identification and setting state 630 and return to the selection state 610 before entering the power delivery state 640. [ For example, the wireless power transmission apparatus 100 may terminate the identifying and setting state 630 to find another wireless power receiving apparatus capable of receiving power wirelessly.

4) Power transmission status ( Power Transfer Phase )

The wireless power transmission apparatus 100 in the power transmission state 640 transmits power to the wireless power receiving apparatus 200. [

The wireless power transmission apparatus 100 receives a power control message from the wireless power receiving apparatus 200 during transmission of power and adjusts a characteristic of power applied to the transmission coil in accordance with the received power control message . For example, a power control message used to adjust the power characteristic of the transmission coil may be included in a control error packet 5500 as shown in FIG. The packet 5500 may be configured to include a header 5520 indicating that the packet is a control error packet and a message 5530 including a control error value. The wireless power transmission apparatus 100 may adjust the power applied to the transmission coil according to the control error value. That is, the current applied to the transmission coil is maintained when the control error value is 0, decreased when the control value is a negative value, and can be adjusted to increase when the control value is a positive value.

In the power transmission state 640, the wireless power transmission apparatus 100 may monitor parameters in a power transfer contract generated based on the identification information and / or the setting information. As a result of monitoring the parameters, if the power transmission to the wireless power receiving apparatus 200 violates the limitations contained in the power transfer protocol, the wireless power transmission apparatus 100 cancels the power transmission The selection state 610 can be returned.

The wireless power transmission apparatus 100 may terminate the power transmission state 640 based on the power control message transmitted from the wireless power receiving apparatus 200. [

For example, if the charging of the battery is completed while the wireless power receiving apparatus 200 is charging the battery using the transmitted power, the power requesting the wireless power transmission apparatus 100 to stop wireless power transmission Control messages can be transmitted. In this case, the wireless power transmission apparatus 100 may terminate the wireless power transmission and return to the selected state 610 after receiving the message requesting the suspension of the power transmission.

As another example, the wireless power receiving apparatus 200 may transmit a power control message requesting renegotiation or reconfiguration to update the already generated power transfer protocol. The wireless power receiving apparatus 200 may transmit a message requesting renegotiation of the power transfer protocol when a power amount that is more or less than the currently transmitted power amount is required. In this case, the wireless power transmission apparatus 100 may terminate the wireless power transmission and return to the identification and setting state 630 after receiving the message requesting renegotiation of the power transfer protocol.

To this end, the message transmitted by the wireless power receiving apparatus 200 may be, for example, an End Power Transfer Packet 5600 as shown in FIG. The packet 5600 may be configured to include a header 5620 indicating that the packet is a power transmission interruption packet and a message 5630 including a power transmission interruption code indicating the reason for the interruption. The power transmission interruption code may be a code for determining whether or not the power transmission interruption code is in a state of charge completion, an internal fault, an over temperature, an over voltage, an over current, a battery failure, a reconfigure, No Response, or Unknown.

A communication method of a plurality of electronic devices

Hereinafter, a method in which one or more electronic devices from one wireless power transmission apparatus performs communication using a wireless power signal will be described.

19 is a conceptual diagram showing a method by which a wireless power transmission apparatus transmits electric power to one or more wireless power reception apparatuses.

The wireless power transmission apparatus 100 may transmit power for one or more wireless power receiving apparatuses 200, 200 '. Although two electronic devices 200 and 200 'are shown in FIG. 19, the method according to the embodiments disclosed herein is not limited to the number of electronic devices shown.

The active area and the sensing area differ depending on the wireless power transmission scheme of the wireless power transmission apparatus 100. Therefore, the wireless power transmission apparatus 100 may be configured to determine whether there is a wireless power receiving apparatus disposed in an active region or a sensing region of a resonant coupling scheme, or whether a wireless power receiving apparatus It can be determined whether or not it exists. According to the determination result, the wireless power transmission apparatus 100 supporting each wireless power transmission scheme can change the power transmission scheme for each wireless power reception apparatus.

In the wireless power transmission according to the embodiments disclosed herein, when the wireless power transmission device 100 transmits power for one or more electronic devices 200, 200 'in the same wireless power transfer mode, (200, 200 ') can perform communication through the wireless power signal without colliding with each other.

The wireless power signal 10a formed by the wireless power transmission apparatus 100 reaches the first electronic device 200 'and the second electronic device 200, as shown in FIG. The first electronic device 200 'and the second electronic device 200 may transmit a power control message using the generated wireless power signal.

The first electronic device 200 'and the second electronic device 200 operate as power receiving devices for receiving wireless power signals. The power receiving apparatus according to embodiments disclosed herein may include a power receiving unit (291 ', 291) for receiving the formed wireless power signal; A modulation and demodulation unit (293 ', 293) for modulating and demodulating the received wireless power signal; And control units 292 'and 292 for controlling the respective components of the power receiving apparatus.

The wireless power transmission / reception method of the present invention has been described above with reference to the WPC standard. Further, the present invention proposes a method of combining a single coil to deliver power to radio power receiving devices conforming to different standards in accordance with each standard. Furthermore, the present invention provides a new type of multi-coil solution that is compatible with the WPC standard and the PMA standard, while also extending the degree of positional freedom of receiving apparatuses. Hereinafter, this will be described in more detail.

A method for transmitting and receiving wireless power using a flux link between the wireless power transmission apparatus 100 and the wireless power reception apparatus 200 includes the steps of transmitting the wireless power transmission apparatus 100 and / When an external metallic material (for example, a metallic material (conductor) such as a metal cup, a can, etc.) is placed at a position adjacent to the power receiving apparatus 200, the external metallic material may be heated by the magnetic flux.

20 is an exemplary view showing a cause of heat generation of an external metallic material 300 located in a wireless power transmission apparatus 100 according to an embodiment of the present invention.

20, when a magnetic flux B passes through the external metal material (conductor) 300, a sine of an angle (?) Formed by the surface of the external metallic material 300 and the magnetic flux, A current I proportional to the value of the current I is induced which causes a heat generation proportional to the resistance value calculated from the resistivity coefficient p of the external metallic material 300. [

Therefore, in the present invention, an apparatus and method for measuring a substantial amount of power that can cause heat generation of the outer metallic material 300 among the wireless powers transmitted from the wireless power transmission apparatus 100 will be described. In order to solve the compatibility problem, in the present invention, the actual amount of power that can cause the heating of the outer metallic material 300 only in the wireless power transmission apparatus 100 is measured in a state in which the wireless power receiving apparatus 200 is not affected Desc / Clms Page number 2 > apparatus and method thereof. For example, when the driving of the transmission coil 1111 is stopped in the wireless power transmission systems 100 and 200 using the flux-linkage, the generation of heat is caused based on the attenuation amount of the resonance energy of the wireless power transmission device 100 The presence or absence of an external substance that can be determined. In order to eliminate the influence of the wireless power receiving apparatus 200, the energy of the wireless power receiving apparatus 200 is set not to be consumed.

FIG. 21 is an exemplary view showing an outer metallic material positioned between the wireless power transmission apparatus 100 using the flux-linkage and the wireless power reception apparatus 200 according to an embodiment of the present invention.

As shown in Fig. 21, a wireless power transmission apparatus 100 using a flux linkage includes a transmission coil 1111 composed of an LC resonant circuit in which a capacitor C is connected in series or in parallel, and the wireless power receiving apparatus 200 includes a receiving coil 2911 composed of an LC resonant circuit in which a capacitor C is connected in series or in parallel. Power is supplied to the wireless power receiving apparatus 200 due to a component of the magnetic flux generated when the power conversion unit 111 applies AC power to the transmission coil 1111 and the receiving coil 2911, Lt; / RTI > The transmission coil 1111 and the reception coil 2911 are constituted by LC resonance circuits (or resonance tanks) in which the capacitors C are connected in series or in parallel. By adjusting the impedance using the LC resonance circuit, Power may be transmitted to the wireless power receiving apparatus 200.

In the resonant circuit formed of the inductor L and the capacitor C, L and C exchange energy with each other and resonate. The inverter in the power conversion unit 111 drives the LC resonant circuit at a resonant frequency or at a frequency higher than a resonant frequency in a steady state in which energy is transmitted in a wireless manner.

22A and 22B are _graphs showing changes in inductor L current (ΔI _RESO ) when the inverter of the wireless power transmission apparatus 100 drives the LC resonance circuit and suddenly (temporarily) stops driving according to the embodiment of the present invention. Fig. 22A shows a change in current of the inductor L when the LC resonant circuit of the wireless power transmission apparatus 100 is driven at a resonant frequency 22-2 and stopped, 100) at the frequency 22-3 higher than the resonance frequency 22-2 and then stopped. Reference numeral 22-1 denotes a driving voltage (current) of the LC resonance circuit. That is, even if the LC resonance circuit is driven at the resonance frequency 22-2 or at the frequency 22-3 higher than the resonance frequency 22-2 and the driving is temporarily stopped, the change in the inductor L current (? I _RESO ) are the same (no change).

As shown in FIGS. 22A and 22B, when the inverter of the wireless power transmission apparatus 100 drives the LC resonance circuit and stops driving the resonance circuit, the resonance energy of the LC resonance circuit of the wireless power transmission apparatus 100 is gradually attenuated . Taking the current of L as a value representative of the energy of the LC resonant circuit of the wireless power transmission apparatus 100 as an example, If the current is changed from the current I ₁ to the second current I ₂ , the following Equation 2 is established.

는 상기 무선 전력 전송장치(100)에서 손실되는 전체 손실 전력량을 나타내며, f는 상기 무선 전력 전송장치(100)의 LC 공진 회로를 구동하는 주파수를 나타내며, L_COIL 상기 무선 전력 전송장치(100)의 LC 공진 회로의 인덕터(L) 값을 나타내며,

은 상기 무선 전력 전송장치(100)의 LC 공진 회로를 구동시키다가 멈춘 시점부터 제1 미리설정된 시간(또는 미리설정된 사이클 수)이 경과한 제1 시점에 검출된 인덕터(L)의 제1 전류를 나타내며,

은 상기 무선 전력 전송장치(100)의 LC 공진 회로를 구동시키다가 멈춘 시점부터 제2 미리설정된 시간(또는 미리설정된 사이클 수)이 경과한 제2 시점에 검출된 인덕터(L)의 제2 전류를 나타내며, 상기 제1 시점은 상기 제2 시점보다 빠르게 설정된다. 상기 제1 및 제2 미리설정된 시간은 상기 무선 전력 전송장치(100)의 LC 공진 회로를 구동시키다가 멈춘 시점부터 상기 인덕터(L)의 전류가 더 이상 검출되는 않는 시점까지의 시간 내에 포함될 수 있다.here,

F represents the frequency at which the LC resonant circuit of the wireless power transmission apparatus 100 is driven, and L _COIL represents the frequency at which the wireless power transmission apparatus 100 is powered on. Represents an inductor (L) value of the LC resonance circuit,

The first current of the inductor L detected at the first time point at which the first predetermined time (or a preset number of cycles) has elapsed since the LC resonance circuit of the wireless power transmission apparatus 100 was stopped and stopped Lt; / RTI &

The second current of the inductor L detected at the second time point when a second predetermined time (or a predetermined number of cycles) has elapsed since the LC resonance circuit of the wireless power transmission apparatus 100 was stopped and stopped And the first viewpoint is set faster than the second viewpoint. The first and second preset times may be included within a time from when the LC resonant circuit of the wireless power transmission apparatus 100 is stopped to when the current of the inductor L is no longer detected .

), 상기 무선 전력 전송장치(100)에서 손실된 고유 전력량(P_LOSS), 상기 외부 금속 물질에서의 발열 등으로 인해 상기 무선 전력 전송장치(100)에서 손실된 전력량(P_FO) 등을 구할 수 있다. _T kP is a power amount to be transmitted to the wireless power receiving apparatus 200, the coefficient k is shown because it also has an LC resonant circuit wherein the wireless power receiving device 200. P _LOSS is the amount of intrinsic power lost in the wireless power transmission apparatus 100 by the element generated by the parasitic resistance, the loss of the core of the wireless power transmission apparatus 100, and the like And represents the amount of intrinsic power lost in the power transmission apparatus 100. P _FO represents the amount of power lost in the wireless power transmission apparatus 100 due to heat generation in the external metallic material or the like. Here, when the inverter of the wireless power transmission apparatus 100 drives the LC resonance circuit and stops its operation, the power transmission control unit 112 controls the total power loss amount

), The amount of power lost (P _FO ) in the wireless power transmission apparatus (100) due to the loss of the inherent power amount (P _LOSS ) in the wireless power transmission apparatus (100) have.

)를 검출하고, 그 검출한 전체 손실 전력량(

)과 상기 무선 전력 전송장치(100)의 고유 손실 전력량(P_LOSS)의 차이값을 상기 외부 금속 물질(300)로 인해 소모되는 전력량(P_FO)으로 결정한다.As can be seen from Equation (2), the power transmission control unit 112 stores P _LOSS as a constant value in advance, blocks the driving of the LC resonance circuit of the wireless power receiving apparatus 200, The power amount P _FO consumed by the external metal material 300 can be obtained by setting the state P _T = That is, the power transmission control unit 112 sets the state of P _T = 0, stops the operation of the LC resonance circuit of the wireless power transmission apparatus 100, and stops the total loss (loss) of the wireless power transmission apparatus 100 power(

), And detects the total loss power amount (

(P _LOSS ) of the wireless power transmission apparatus 100 is determined as a power amount P _FO consumed due to the external metallic material 300.

)에서 제2 전류(

)를 감산한 값과 "

"의 결과 값을 곱함으로써 구해진 값을 상기 무선 전력 전송장치(100)에서 손실되는 전체 손실 전력량(

)으로서 결정한다.The power transmission control unit 112 sets the state of P _T = 0, and controls the power transmission control unit 112 to set the state of P _T = 0 for a predetermined time (or a predetermined number of cycles) from the time when the LC resonance circuit of the wireless power transmission apparatus 100 is stopped, 1 current

) To the second current (

) And the value obtained by subtracting "

Quot; obtained by multiplying the resultant value of the power loss "

).

23 is a graph showing the relationship between the output voltage of the LC resonant circuit of the wireless power transmission apparatus 100 and the resonant frequency of the external And the attenuation curve 23-1 of the resonance energy.

As shown in Fig. 23, it can be seen that the envelope envolop has a damping coefficient alpha and attenuates temporally along e-alpha ^t . As the attenuation coefficient by P _LOSS, factors involved in P _LOSS is loss occurring in the assembly (assembly) of the magnetic resistance, the wireless power transmission apparatus 100 is generated in the equivalent resistance of the coil, the coil core, external metal The loss power P _LOSS in the wireless power transmission apparatus 100 can be obtained in advance by measuring the wireless power transmission apparatus 100 alone as a self loss component not related to the material.

When the wireless power receiving apparatus 200 is connected to the wireless power transmission apparatus 100, the power transmission control unit 112 transmits a control signal P (P) for stopping the operation of the LC resonant circuit of the wireless power receiving apparatus 200 ₍ A control signal for setting _T = 0) and transmits the control signal (control signal for setting P _T = 0) to the wireless power receiving apparatus 200. The wireless power receiving apparatus 200 stops the driving of the LC resonant circuit on the basis of their (a control signal for setting the P _T = 0) the control signal (set as P _T = 0). The power transmission control unit 112 periodically or whenever a time set by the user elapses to detect the presence of the external metallic material 300 and / or the amount of power consumed by the external metallic material 300 Generates a control signal for stopping the driving of the LC resonant circuit of the wireless power receiving apparatus 200 and transmits the control signal to the wireless power receiving apparatus 200. [

Hereinafter, a method of setting P _T = 0 will be described with reference to FIGS. 24 and 25. FIG.

24 is an exemplary view showing a circuit for setting P _T = 0.

24, when the wireless power receiving apparatus 200 is connected to the wireless power transmission apparatus 100, the power transmission control unit 112 periodically transmits power to the LC resonant circuit 200 of the wireless power receiving apparatus 200, P _T = 0 is set by turning off the diodes D 1 to D 4 of the rectifier 24 - 1 connected to the rear end of the rectifier 2911. For example, the wireless power receiving apparatus 200 may open the rectifier 24-1 based on the control signal (control signal for setting P _T = 0) of the power transmission control unit 112, And sets P _T = 0 by blocking the current applied to the LC resonance circuit 2911 of the wireless power receiving apparatus 200.

25 is an exemplary view showing another circuit for setting P _T = 0.

25, when the wireless power receiving apparatus 200 is connected to the wireless power transmission apparatus 100, the power transmission control unit 112 periodically transmits power to the LC resonant circuit 200 of the wireless power receiving apparatus 200, To set P _T = 0. For example, the wireless power receiving apparatus 200 may be configured to receive power from the switching devices (not shown) in the rectifier 25-1 based on the control signal (control signal for setting P _T = 0) of the power transmission control unit 112 The LC resonance circuit 2911 of the wireless power receiving apparatus 200 is short-circuited by shorting the diodes D3 and D4 by turning on the transistors M1 and M2.

FIG. 26 is a schematic diagram showing a configuration of the wireless power transmission apparatus 100 in a state in which the wireless power receiving apparatus 200 (in which the LC resonant circuit is short-circuited) 200 and the wireless power transmission apparatus 100 are not provided, The resonance energy attenuation curve 26-1 at the time of stopping the driving of the LC resonance circuit of Fig.

Fig. 27 shows a waveform in which the current waveform of Fig. 23 and the current waveform of Fig. 26 are superimposed. The attenuation curve 23-1 of Fig. 23 and the attenuation curve 26-1 of resonance energy of Fig. It can be confirmed that it is not influenced by the presence or absence of the wireless power receiving apparatus (LC resonant circuit is short-circuited) 200. That is, it can be seen that the attenuation coefficient of the resonance energy of FIG. 23 and the attenuation coefficient of the resonance energy of FIG. 26 are almost not different from each other.

28 is a graph showing the attenuation curve (attenuation coefficient) of the resonance energy when the LC resonance circuit of the wireless power transmission apparatus 100 is stopped in the state in which the wireless power transmission apparatus 100 is not provided without the external metallic material 300, And a resonance energy attenuation curve when stopping driving of the LC resonance circuit of the wireless power transmission apparatus 100 in a state that the external metallic material 300 exists in the wireless power transmission apparatus 100 Damping coefficient) 28-1.

28, the resonance energy accumulated in the LC resonance circuit of the radio-frequency power transmission apparatus 100 according to the presence or absence of the external metal material 300 when the radio-frequency power transmission apparatus 100 is present alone Which is a representative value of the inductor coil current. That is, the damping coefficient? Of the resonance energy is clearly distinguished according to the presence or absence of the external metallic material 300.

FIG. 29 is a view showing a state in which when the radio power receiving apparatus 200 is not located in the radio power transmission apparatus 100 without the external metallic material 300, the radio wave transmission apparatus 100 stops driving the LC resonant circuit of the radio power transmission apparatus 100 The attenuation curve (attenuation coefficient) 29-1 of the resonant energy and the wireless power receiving apparatus 200 are located in the wireless power transmission apparatus 100 and the external metallic material 300 is applied to the wireless power transmission apparatus 100, (Attenuation coefficient) 29-1 at the time of stopping the driving of the LC resonance circuit of the wireless power transmission apparatus 100 in a state in which the attenuation curve (attenuation coefficient) 29-1 of the resonance energy is stopped. That is, the damping coefficient? Of the resonance energy is clearly distinguished according to the presence or absence of the external metallic material 300.

When the power transmission control unit 112 stops the operation of the LC resonant circuit of the wireless power transmission apparatus 100, the envelope of the current (or voltage) of the LC resonant circuit of the wireless power transmission apparatus 100 reaches a predetermined size The presence or absence of the external metal material may be determined based on the number (or time) of resonance cycles (or time) required for the reduction. When the power transmission control unit 112 stops driving the LC resonance circuit of the wireless power transmission apparatus 100, the power transmission control unit 112 outputs the LC resonance of the wireless power transmission apparatus 100 after a predetermined number of resonance cycles (or after a preset time) The presence or absence of the external metallic material may be determined based on the envelope size of the current (or voltage) remaining in the circuit.

The power transmission control unit 112 may determine the presence or absence of the external metallic material on the basis of the attenuation coefficient of the resonance energy and a predetermined reference attenuation coefficient (threshold value).

30 is a flowchart illustrating a method for determining the presence or absence of the external metal material according to an embodiment of the present invention.

First, the power transmission control unit 112 temporarily stops the operation of the LC resonance circuit of the wireless power transmission apparatus 100 (S11) periodically or after a time set by the user has elapsed. For example, the power transmission control unit 112 may determine whether the external power source 300 is connected to the wireless power transmission apparatus 100 even when the wireless power reception apparatus 200 is not connected to the wireless power transmission apparatus 100 The driving of the LC resonant circuit of the wireless power transmission apparatus 100 is temporarily performed (for example, during the time when the resonance energy becomes zero from the time when the driving of the LC resonance circuit of the wireless power transmission apparatus 100 is stopped) Stop.

When the driving of the LC resonant circuit of the wireless power transmission apparatus 100 is stopped, the power transmission control unit 112 detects the attenuation coefficient of the resonant energy of the LC resonant circuit of the wireless power transmission apparatus 100 (S12).

The power transmission control unit 112 determines whether the detected attenuation coefficient exceeds a preset reference attenuation coefficient (S13). Wherein the predetermined reference attenuation factor is selected such that when the radio power transmission device 100 alone is present without the outer metallic material 300 and the radio power receiving device 200, And the attenuation coefficient of the resonance energy of the LC resonance circuit of the wireless power transmission apparatus 100 is detected in advance and defined as the attenuation coefficient detected in advance.

The power transmission control unit 112 determines that the external metal material 300 is detected when the detected damping coefficient exceeds the preset reference damping coefficient (S14).

When the external metallic material 300 is detected, the power transmission control unit 112 generates information (e.g., an error code) indicating that the external metallic material 300 has been detected and transmits the information to the display unit 141 (S15).

On the other hand, if the detected damping coefficient does not exceed the preset reference damping coefficient, the power transmission control unit 112 performs a method of periodically determining the presence or absence of the external metallic material 300.

31 is a flowchart illustrating another method for determining the presence or absence of the external metal material according to an embodiment of the present invention.

When the wireless power receiving apparatus 200 is connected to the wireless power transmission apparatus 100, the power transmission control unit 112 transmits the wireless power to the wireless power receiving apparatus 200 periodically or to the user The operation of the LC resonant circuit of the wireless power receiving apparatus 200 is temporarily stopped (S21). For example, when the wireless power receiving apparatus 200 is connected to the wireless power transmission apparatus 100, the power transmission control unit 112 transmits the wireless power to the wireless power transmission apparatus 100, The operation of the LC resonant circuit of the wireless power receiving apparatus 200 is temporarily stopped for a period of time to detect the presence or absence of the power supply 300.

The power transmission control unit 112 stops driving the LC resonance circuit of the wireless power receiving apparatus 200 and temporarily stops driving the LC resonance circuit of the wireless power transmission apparatus 100 at step S22.

The power transmission control unit 112 temporarily suspends driving of the LC resonance circuit of the wireless power receiving apparatus 200 and the LC resonance circuit of the wireless power transmission apparatus 100, The attenuation coefficient of the resonance energy of the resonance circuit is detected (S23).

The power transmission control unit 112 determines whether the detected attenuation coefficient exceeds a preset reference attenuation coefficient (S24). The predetermined reference attenuation coefficient is set such that when the radio power transmission apparatus 100 and the radio power reception apparatus 200 are connected without the external metal material 300, the LC resonance circuit of the radio power transmission apparatus 100 The damping coefficient of the resonance energy of the LC resonance circuit of the wireless power transmission apparatus 100 is detected in advance after the drive is temporarily stopped and is defined as the damping coefficient detected in advance.

The power transmission control unit 112 determines that the external metallic material 300 is detected when the detected attenuation coefficient exceeds the predetermined reference attenuation coefficient at step S25.

When the external metallic material 300 is detected, the power transmission control unit 112 generates information (e.g., an error code) indicating that the external metallic material 300 has been detected and transmits the information to the display unit 141 (S26).

On the other hand, when the detected attenuation coefficient does not exceed the predetermined reference attenuation coefficient, the power transmission control unit 112 transmits information indicating that the wireless power is normally transmitted to the wireless power receiving apparatus 200, (S27).

INDUSTRIAL APPLICABILITY As described above, the wireless power transmission apparatus and the control method thereof according to the embodiments of the present invention can determine the presence or absence of the external metallic material by detecting the attenuation coefficient of the resonance energy of the LC resonance circuit of the wireless power transmission apparatus .

As described above, the wireless power transmission apparatus and the control method thereof according to the embodiments of the present invention can determine the presence or absence of the external metallic material by detecting the attenuation coefficient of the LC resonant circuit.

Hereinafter, a wireless power transmission apparatus according to embodiments of the present invention will describe a method of detecting the type of external material, the alignment state and the capacity of the receiving apparatus based on the rate of change of the attenuation coefficient per cycle. FIG. 32 is a flowchart showing a method of detecting the type of foreign substance, the alignment state and the capacitance of the receiving apparatus based on the rate of change per period of the attenuation coefficient, FIGS. 35, 36 and 37 show attenuation FIG. 38, FIG. 39, and FIG. 40 are graphs showing that the attenuation coefficient per cycle is changed when there is a receiving apparatus.

The wireless power transmission apparatus according to an embodiment of the present invention may perform a step of periodically generating a waveform of a specific frequency to detect an external material (S310).

The wireless power transmission device may detect whether there is any external material capable of receiving power wirelessly within a certain distance capable of transmitting the wireless power. Here, the detection of the presence of the foreign substance is to prevent the case of transmitting the wireless power even though the substances not suitable for wireless charging are aligned. If wireless power is transmitted to a material that is not suitable for wireless charging, there is a risk of damage to the wireless charging system.

At this time, in order to determine whether the external device is a device that receives power wirelessly, the power transmission control part 112 provided in the wireless power transmission device may periodically generate a waveform having a specific frequency.

Here, the specific frequency may be higher than the resonance frequency inherent to the wireless power transmission apparatus.

On the other hand, the waveform having the specific frequency may change the characteristics of the waveform when the external material exists within a specific distance based on the wireless power transmission apparatus. Here, the characteristic of the waveform may be a frequency of a waveform, a damping coefficient, and the like.

At this time, in the wireless power transmission apparatus according to the embodiment of the present invention, the attenuation coefficient of the waveform may be detected in each period of the waveform, and the variation of the attenuation coefficient may be measured (S320).

The power transmission control unit 112 can detect the attenuation coefficient for each period of the waveform.

At this time, the attenuation coefficient of the waveform may vary depending on the presence or absence of foreign matter within a specific distance based on the wireless power transmission apparatus. Here, the specific distance set on the basis of the wireless power transmission apparatus may mean a distance over which the wireless power transmission apparatus can transmit power wirelessly. Referring to the graphs of FIGS. 35, 36, and 37, it can be seen that the damping coefficient changes in one cycle depending on the presence or absence of foreign substances.

More specifically, the graph of Fig. 35 shows the waveform of the power transmission coil provided in the wireless power transmission apparatus when there is no external material within a specific distance of the wireless power transmission apparatus. The graph of FIG. 36 shows the waveform of a power transmission coil provided in the wireless power transmission apparatus when there is an external metallic material within a specific distance of the wireless power transmission apparatus. 35 and 36, it can be seen that the damping coefficient is different when the external material is present.

Further, the graph of FIG. 37 shows the waveform of the power transmission coil provided in the wireless power transmission apparatus when there is a reception apparatus capable of receiving wireless power within a specific distance of the wireless power transmission apparatus. 35, 36 and 37, it can be seen that the damping coefficient is different. In Fig. 37, it can be seen that there is a waveform having an additional frequency due to the presence of the receiving apparatus.

Accordingly, the power transmission control unit 112 can determine the presence or absence of an external substance. Accordingly, the present invention can protect the wireless charging system by controlling the wireless power to be transmitted only when there is an external object within a specific distance at which the wireless power can be transmitted.

After measuring the change amount of the damping coefficient, the wireless power transmission apparatus according to an embodiment of the present invention can determine the type of the external material based on the variation amount of the damping coefficient of the waveform (S330).

The power transmission control unit 112 can determine the type of the foreign substance based on the presence or absence of external substances as well as the amount of change in the attenuation coefficient in each period. The attenuation coefficient may be changed according to the period by a capacitor provided in the rectifying unit of the receiving apparatus for receiving the radio power.

More specifically, the capacitor provided in the rectifying unit of the receiving apparatus may be energized by a waveform having a specific frequency transmitted from the transmitting apparatus. At this time, the voltage of the capacitor of the rectifying unit of the receiver increases due to the stored energy. Thus, the ratio of the voltage / current applied to the capacitor is changed, the equivalent resistance indicated by the capacitor is changed, and the equivalent resistance of the entire system of the receiving apparatus can be changed. Therefore, due to the change of the equivalent resistance of the capacitor included in the receiving apparatus, the attenuation coefficient of the waveform sensed at the power transferring section coil (coil of the LC resonance circuit) of the transfer apparatus can be changed.

 The power transmission control unit 112 may detect a variation amount of attenuation coefficients in each period. More specifically, referring to the graphs of FIGS. 38, 39 and 40, it can be seen that the damping coefficient in each cycle for one waveform gradually decreases.

More specifically, FIG. 38 shows the attenuation coefficient in the first period of the waveform, FIG. 39 shows the attenuation coefficient in the second period of the waveform, and FIG. 40 shows the attenuation coefficient in the third period of the waveform. As can be seen from FIG. 38 through FIG. 40, the attenuation coefficient of the waveform gradually decreases.

The amount of change in the damping coefficient may vary depending on the kind of the external material. For example, the amount of change in attenuation coefficient of a receiving device of wireless power and an external device not receiving wireless power may be different.

Accordingly, the power transmission control unit 112 can detect the type of the foreign substance based on the variation amount of the damping coefficient. More specifically, the power transmission control unit 112 may detect a receiving apparatus configured to receive radio power when the amount of change in the attenuation coefficient coincides with a preset reference change amount.

After detecting the external material, the wireless power transmission apparatus according to an embodiment of the present invention may proceed to determine whether to transmit power wirelessly to the external material, based on the type of the external material (S340 ).

The power transmission control unit 112 may determine whether the external material is a reception device capable of wirelessly receiving power based on the variation amount of the damping coefficient. At this time, when the external material is a receiving device capable of receiving power wirelessly, the power transmission control unit 112 can control the power supply unit 190 to transmit power to the receiving device. In addition, when the external material is a substance that can not receive power wirelessly, the power transmission control unit 112 may control the power supply unit 190 so as not to transmit power to the external material.

In addition, the power transmission control unit 112 may detect the type of the external material based on a waveform having a waveform detected by the power transmission coil having an additional frequency different from the resonant frequency of the wireless power transmission apparatus.

For example, the power transmission control unit 112 may detect a waveform having an additional frequency different from a resonance frequency inherent to the wireless power transmission apparatus, at a frequency of a waveform sensed by the power transmission coil .

Here, the additional frequency value may be a value depending on mutual inductance values between the coils provided in the transmitting apparatus and the receiving apparatus, respectively. At this time, since the additional frequency value depends on the mutual inductance value, the power transmission control unit 112 can determine the alignment state of the transmitting apparatus and the receiving apparatus based on the additional frequency value. The alignment state may mean that the transmitting apparatus is in a position suitable for wirelessly transmitting power to the receiving apparatus.

Further, the power transmission control unit 112 can estimate not only the alignment state but also the capacitance of the capacitor of the reception apparatus using the waveform having the additional frequency. More specifically, the power transmission control unit 112 can infer the capacitance of the capacitor of the receiver using the mutual inductance value and the additional frequency value. Accordingly, the power transmission control unit 112 can determine the amount of power of the wireless power to be transmitted to the receiving apparatus.

Further, depending on the type of the external material, the frequency to be detected may be further varied. For example, since the structure of the receiver for receiving the radio power differs from that for the kitchen appliance and the heating appliance having the motor, different frequencies can be detected in the power transmission coil of the transmission device. Accordingly, the power transmission control unit 112 can detect the type of the foreign substance by using the characteristics in which the different frequencies are detected. Accordingly, the power transmission control unit 112 may control the power supply unit 190 to transmit the wireless power according to the characteristics of the receiving apparatus.

As described above, a wireless power transmission apparatus according to an embodiment of the present invention uses at least one of a change amount of a damping coefficient of a waveform and a waveform having an additional frequency to change the type of a receiving apparatus and the alignment state of the receiving apparatus, The capacity of the receiving apparatus can be determined.

In the foregoing, a method of detecting the type of foreign substance by the wireless power transmission apparatus has been described. Accordingly, the wireless power transmission apparatus can distinguish the wireless power reception apparatuses from each other without any separate communication with the wireless power reception apparatuses. Furthermore, the present invention can provide a method for determining the type of external material in the vicinity of the wireless power transmission apparatus and transmitting suitable wireless power.

Meanwhile, in transmitting a wireless power, in-band communication using a power transmission coil for communication is used in order to share information between the transceivers in a few watts-class wireless power transmission system.

However, in a wireless power transmission system that transmits power of a few kilo Watt class, a large power is supplied to the power transmission coil, so that it is not suitable for use for communication. This is because, when the power transmission coil is used for communication, the absolute amount of power to be lost is very large even if a reduction in the power efficiency is extremely small for communication. In addition, since an element usable at a node to which a large electric power is applied is also high in price, it may be difficult to use a coil for transmitting a large electric power for communication.

Therefore, a method of using a separate communication module has been proposed in a wireless power transmission system that transmits and receives power of several kilo Watt. Such a communication method using a separate communication module can be called an out-of-band communication.

On the other hand, when using the separate communication module, a method for ensuring 1: 1 communication between the transceivers and a method for safely stopping communication when the transceiver is disconnected may be a problem.

Hereinafter, a method of performing communication with a wireless power transmission apparatus according to an embodiment of the present invention will be described in order to solve the above problems. 33 is a flowchart illustrating a method of performing communication in a wireless power transmission apparatus according to an embodiment of the present invention. 6. The method of claim 5,

At this time, before the communication is performed, the power transmission control unit 112 may perform the step of detecting the type of the foreign substance first (S340). The step of detecting the type of the foreign substance may be performed in the same manner as described above.

If the external material is a reception device configured to receive wireless power, the power transmission control unit 112 may control the wireless communication unit to perform communication before transmitting power to the reception device wirelessly.

That is, the wireless power transmission apparatus according to an exemplary embodiment of the present invention may transmit the communication information and predetermined power required for performing the communication to the receiving apparatus (S341). Here, the communication information may be identification information (e.g., SSID), security information, and the like.

The predetermined power may be the power required to drive the wireless communication unit included in the receiving apparatus. At this time, the predetermined amount of electric power may be a predetermined amount. Further, the predetermined power may be used in the receiving apparatus at a later time when power is used to drive the wireless communication unit and a predetermined power remains.

The power transmission control unit 180 may transmit the communication information and the predetermined power using a frequency higher than a resonance frequency inherent to the transmission apparatus. For example, the power transmission control unit 180 can transmit communication information and predetermined power using two frequencies f1 and f2 higher than the resonance frequency.

At this time, the power transmission control unit 180 can transmit the communication information and the predetermined power without feedback of the receiving apparatus. Further, the receiving apparatus receiving the communication information and the predetermined power may perform the amplitude demodulation using the amplitudes of the two frequencies f1 and f2 different from each other. If the amplitude demodulation is difficult, the signal can be analyzed through the frequency demodulation. have.

Accordingly, the transmission apparatus and the reception apparatus can perform communication in a 1: 1 ratio using the demodulated signal.

The wireless power transmission apparatus according to an exemplary embodiment of the present invention may wirelessly transmit power to the receiving apparatus after the communication is performed (S342). If the external device is not a receiving device, the power supply unit 190 may be controlled so as not to transmit power wirelessly (S343).

When the communication is connected, the power transmission control unit 180 can receive the power amount information to be transmitted from the receiving apparatus through the communication. Thereafter, the power transmission control unit 112 can transmit power to the receiving apparatus wirelessly based on the power amount information.

In the foregoing, a method of communicating between the wireless power transmission apparatus and the reception apparatus has been described. Through this, the wireless power transmission apparatus can secure 1: 1 communication to the transmitting apparatus and the receiving apparatus even when transmitting power of several kilo Watt.

Hereinafter, a method of stopping the transmission of the wireless power while the wireless power transmission apparatus transmits the wireless power to the reception apparatus will be described. 34 is a flow chart illustrating a method for interrupting the transmission of power wirelessly.

The wireless power transmission apparatus according to an exemplary embodiment of the present invention may receive a request signal for interrupting the power supply from the receiving apparatus through communication while transmitting power wirelessly to the receiving apparatus at step S410.

The communication may be performed through the communication method described above with reference to FIG. 33, and the transmission of the wireless power may be performed by the method described above with reference to FIG.

The request signal may include alignment status information indicating that the alignment status of the receiving apparatus has been changed. For example, the request signal may include information indicating that the receiving device is currently unable to receive wireless power from the transmitting device.

The receiving apparatus may transmit a request signal to the wireless power transmission apparatus to stop the supply of the power based on a predetermined condition.

Here, the predetermined condition may be a condition that the voltage of the capacitor provided in the rectifying unit of the receiving device drops below a reference value, a condition that the voltage drop duration of the capacitor provided in the rectifying unit is equal to or longer than the reference time, And a condition that the current value flowing in the resistor R falls below the reference value.

That is, if at least one of the preset conditions is satisfied, the receiving apparatus can transmit a request signal to the transmitting apparatus to stop the supply of power to be transmitted wirelessly.

At this time, when the request signal is received, the wireless power transmission apparatus according to an embodiment of the present invention may stop transmission of power currently being supplied (S420).

When the request signal is received through the communication, the power transmission control unit 112 may stop the transmission of the power transmitted to the receiving apparatus. At this time, the power transmission control unit 112 may determine that the alignment state of the reception apparatus has been changed. That is, in this case, the power transmission control unit 112 may stop transmission of power transmitted to the receiving apparatus so as not to transmit unnecessary power.

On the other hand, even if the transmission device stops receiving power, the communication may not be disconnected. Through this, the transmitting apparatus can still transmit and receive information from the receiving apparatus.

The wireless power transmission apparatus and the control method thereof according to the embodiments of the present invention can determine the presence or absence of the external metallic material by detecting the attenuation coefficient of the resonance energy of the LC resonance circuit of the wireless power transmission apparatus.

A wireless power transmission apparatus and a control method thereof according to embodiments of the present invention are characterized in that the wireless power reception apparatus controls the wireless power reception apparatus to block the reception of the wireless power and the LC resonance circuit of the wireless power transmission apparatus The amount of power consumed by the external metallic material may be detected on the basis of the total loss power amount of the wireless power transmission apparatus detected at the time of driving and stopping and the loss intrinsic power amount of the wireless power transmission apparatus.

The wireless power transmission apparatus and the control method thereof according to embodiments of the present invention can determine the type of the external material by using the variation amount of the frequency attenuation coefficient of the waveform sensed by the power transmission coil of the wireless power transmission apparatus.

The wireless power transmission apparatus and the control method thereof according to embodiments of the present invention are characterized in that a waveform sensed by a power transmission coil of a wireless power transmission apparatus uses an additional waveform other than the inherent resonance frequency, Can be detected.

A wireless power transmission apparatus and a control method thereof according to an embodiment of the present invention can provide a method of connecting one-to-one communication between a wireless power transmission apparatus and a wireless power reception apparatus. Accordingly, the present invention can provide a method for securely performing communication.

The method described above can be implemented in a recording medium that can be read by a computer or similar device using, for example, software, hardware, or a combination thereof.

According to a hardware implementation, the methods described so far can be applied to various types of application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays microprocessors, microprocessors, and other electronic units for performing other functions. For example, the methods may be implemented using the wireless Or may be implemented in the control unit 180 or the power transmission control unit 112 of the power transmission apparatus 100. [

According to a software implementation, embodiments such as the procedures and functions described herein may be implemented with separate software modules. Each of the software modules may perform one or more of the functions and operations described herein. Software code can be implemented in a software application written in a suitable programming language. The software code is stored in the memory 150 of the wireless power transmission apparatus 100 and can be executed by the control unit 180 or the power transmission control unit 112. [

The configuration of the wireless power transmission apparatus according to the embodiments disclosed herein may be applied to devices such as a docking station, a cradle device, and other electronic devices, May be readily apparent to those skilled in the art.

The scope of the present invention is not limited to the embodiments disclosed herein, and the present invention can be modified, changed, or improved in various forms within the scope of the present invention and the claims.

100: wireless power transmission apparatus 200: wireless power receiving apparatus
111: power conversion unit 112: power transmission control unit
190: Power supply

Claims (20)

A wireless power transmission apparatus capable of transmitting and receiving power wirelessly,
A power supply for supplying electric power to the receiving device wirelessly;
And a power transmission control unit for periodically generating a waveform of a specific frequency, measuring a damping coefficient of the waveform in each of the periods, measuring a change amount of the damping coefficient in each period, and determining a type of the external material,
The power transmission control unit
Based on the kind of the external material, whether or not to transmit the power to the receiving apparatus wirelessly. The method according to claim 1,
The power transmission control unit
Wherein the control unit detects a change amount of an attenuation coefficient varying according to a period of the waveform and determines that the external material is a receiving apparatus that receives power wirelessly when the variation amount of the attenuation coefficient matches a preset reference change amount, And transmits power wirelessly to the base station. 3. The method of claim 2,
Further comprising a wireless communication unit configured to wirelessly communicate with the receiving apparatus,
The power transmission control unit
Wherein the communication unit transmits a predetermined amount of power and communication information related to communication to the receiving apparatus so that communication is performed through the wireless communication unit when the external material is a receiving apparatus that receives the wireless power. . The method of claim 3,
The power transmission control unit
And when the one-to-one communication with the receiving apparatus is completed, transmits power to the receiving apparatus wirelessly. 5. The method of claim 4,
The power transmission control unit
Receives power amount information for receiving radio power from the receiving apparatus through the connected communication, and controls the power supplying section to supply power based on the power amount information. 6. The method of claim 5,
The power transmission control unit
And stops the power supplied to the receiving apparatus when receiving the alignment status information indicating that the alignment status of the receiving apparatus has changed from the receiving apparatus through the connected communication. The method according to claim 1,
The power transmission control unit
Wherein the type of external material is determined based on the characteristics of the other frequency when a frequency different from a predetermined resonance frequency is detected after periodically generating the waveform of the specific frequency. 8. The method of claim 7,
The power transmission control unit
Wherein the type of the external material is detected based on the characteristics of the other frequency and the amount of power to be transmitted wirelessly is determined based on the type of the external material. 8. The method of claim 7,
The power transmission control unit
And detects the capacity of the external material based on the rate of change of the damping coefficient of the other frequency. A transmission device configured to transmit power wirelessly; And
And a receiving device configured to receive wireless power from the transmitting device,
The transmission device
A power supply for supplying electric power to the receiving device wirelessly; And
A method of measuring a damping coefficient of a waveform in each cycle by periodically generating a waveform of a specific frequency and measuring a change amount of a damping coefficient in each cycle to determine whether or not to transmit power wirelessly to the receiving apparatus A wireless charging system comprising a transmission control unit. 11. The method of claim 10,
The transmission device
Further comprising a wireless communication unit configured to wirelessly communicate with the receiving apparatus,
Wherein the power transmission control unit transmits communication information and a predetermined amount of power to the receiving apparatus so as to perform wireless communication with the receiving apparatus prior to wirelessly transmitting power to the receiving apparatus. 12. The method of claim 11,
Wherein the power transmission control unit transmits the communication information and a predetermined amount of power using a frequency higher than a resonance frequency of the transmission apparatus. 12. The method of claim 11,
The power transmission control unit
And controls the power supply unit to transmit power based on the amount of power received from the receiving apparatus via the communication when communication is established with the receiving apparatus based on the communication information. 14. The method of claim 13,
The power transmission control unit
And controls the power supply unit to stop the transmitting power when a request signal is received to stop power transmission from the receiving apparatus. 15. The method of claim 14,
Wherein the receiving device generates the request signal based on at least one of a voltage value, a voltage drop time, and a current value of the receiving device. A wireless power transmission method of a wireless power transmission apparatus for wirelessly transmitting power,
Periodically generating a waveform of a specific frequency;
Detecting a power receiving device that wirelessly receives power based on a variation amount of a damping coefficient in each period of the specific frequency waveform;
When the power receiving device is detected, transmitting to the power receiving device communication link information and power to be used in a communication module of the receiver to communicate with the transmitting device;
Connecting the communication with the receiving apparatus using the communication connection information; And
Receiving power amount information to be wirelessly transmitted from a receiving apparatus using the connected communication, and transmitting power wirelessly based on the received power amount information,
In the step of detecting the power receiving apparatus
Wherein a waveform of the specific frequency is periodically generated, a decay rate in each period is measured, and a receiver is detected using a variation amount of a plurality of decay rates. 18. The method of claim 17,
In the step of detecting the power receiving apparatus
Wherein an alignment state of the reception apparatus is determined using a waveform having a frequency different from a resonance frequency of the transmission apparatus. 18. The method of claim 17,
In the step of transmitting the communication connection information to the power receiving apparatus
Wherein the communication connection information is transmitted using a frequency higher than a resonance frequency of the transmission device. 18. The method of claim 17,
Wherein the transmitting apparatus communicates with the receiving apparatus on a one-to-one basis. 18. The method of claim 17,
The step of wirelessly transmitting power to the receiving device
And stops transmission of the power based on reception of a request signal to stop transmission of power from the receiving apparatus through the communication.

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