KR101897646B1 - Wireless charging apparatus and method thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless power transmission technique, and more particularly, to a wireless charging device capable of high-speed wireless charging and a method thereof.
The wireless power transmitter according to the present embodiment includes a power transmitting unit including a transmitting coil; A power conversion unit for converting an intensity of power applied from the outside; And a control unit for controlling a transmission power to the wireless power receiver, wherein the control unit determines whether the absolute value of the control error value of the control error packet is greater than or equal to a first positive threshold value or a negative first threshold value If the absolute value of the received control error value has an absolute error value equal to or greater than the second threshold value, the transmission power is weighted and transmitted to the wireless power receiver with the weighted reflected power.

Description

[0001] WIRELESS CHARGING APPARATUS AND METHOD THEREOF [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless power transmission technique, and more particularly, to a wireless charging device capable of high-speed wireless charging and a method thereof.

Portable terminals, such as mobile phones and laptops, include a battery for storing power and a circuit for charging and discharging the battery. In order for the battery of such a terminal to be charged, power must be supplied from an external charger.

2. Description of the Related Art [0002] Generally, as an example of an electrical connection between a charging device and a battery for charging electric power of a battery, a commercial electric power is supplied to a terminal for converting electric power into voltage and current corresponding to the battery, Supply method. This type of terminal supply is accompanied by the use of physical cables or wires. Therefore, when handling a lot of terminal-supplied equipment, many cables occupy considerable work space, are difficult to organize, and are not well apparent. Also, the terminal supply method may cause problems such as instantaneous discharge due to different potential difference between terminals, burnout due to foreign substances, fire, natural discharge, battery life and deterioration of performance.

In order to solve such a problem, a charging system (hereinafter referred to as a "wireless charging system") and a control method using a method of transmitting power wirelessly are proposed. In addition, since the wireless charging system has not been installed in some portable terminals in the past and the consumer has to purchase a separate wireless charging receiver accessory, the demand for the wireless charging system is low, but the wireless charging user is expected to increase rapidly. Wireless charging function is expected to be equipped basically.

Generally, a wireless charging system comprises a wireless power transmitter for supplying electric energy in a wireless power transmission mode and a wireless power receiver for receiving electric energy supplied from a wireless power transmitter to charge the battery.

Such a wireless charging system may transmit power by at least one wireless power transmission scheme (e.g., electromagnetic induction scheme, electromagnetic resonance scheme, RF wireless power transmission scheme, etc.).

For example, the wireless power transmission scheme may be based on a variety of wireless power transmission standards based on an electromagnetic induction scheme in which a magnetic field is generated in a power transmitter coil and charged using an electromagnetic induction principle in which electricity is induced in a receiver coil under the influence of its magnetic field . Here, the electromagnetic induction type wireless power transmission standard may include an electromagnetic induction wireless charging technique defined in a Wireless Power Consortium (WPC) or a Power Matters Alliance (PMA).

In another example, the wireless power transmission scheme may employ an electromagnetic resonance scheme in which the magnetic field generated by the transmission coil of the wireless power transmitter is tuned to a specific resonance frequency to transmit power to a nearby wireless power receiver . Here, the electromagnetic resonance method may include a resonance type wireless charging technique defined in the Airfuel (old, A4wp) standard instrument, a wireless charging technology standard organization.

In another example, a wireless power transmission scheme may use an RF wireless power transmission scheme that transmits power to a wireless power receiver located at a remote location by applying low-power energy to the RF signal.

On the other hand, a high-speed wireless charging technology similar to the time of wired charging using an existing cable has been proposed. In the high-speed wireless charging, the high power level is transmitted according to the alignment state of the receiver and the transmitter, so that the time required for charging can be shortened and the efficiency can be high. However, if the receiver can not actively cope with the movement of the receiver, excessive power may be applied to the receiver, or the receiver may be damaged.

The present embodiment is designed to solve the above-described problems of the prior art, and an object of the present embodiment is to provide a wireless charging apparatus and a method thereof.

Another object of the present invention is to provide a wireless charging device capable of high-speed wireless charging and a method thereof.

It is still another object of the present invention to provide a wireless charging device and a method capable of adaptively changing a charging state according to a state and a demand of a wireless power receiving apparatus.

Still another object of the present invention is to provide a stable wireless charging device and method thereof that does not damage the wireless power receiving device depending on the state of the wireless power receiving device during fast charging.

The technical problems to be solved by this embodiment are not limited to the above-mentioned technical problems and other technical problems which are not mentioned are clarified from the following description to those skilled in the art to which the embodiments belong, .

According to an aspect of the present invention, there is provided a wireless power transmitter including: a power transmitter including a transmission coil; A power conversion unit for converting an intensity of power applied from the outside; When the control error value of the control error packet is continuously received below a positive first threshold value or below a first threshold value negative (-), the control unit controls the transmission power to the wireless power receiver, Wherein the controller determines whether the received control error value is an absolute control error value equal to or greater than a second threshold value and reflects the weight to the transmission power if the determined control error value has an absolute control error value equal to or greater than the second threshold value, The power transmission unit transmits power to the wireless power receiver with the weighted reflected power, and the absolute control error value above the second threshold is a positive or negative maximum control error value that can be received from the wireless power receiver.

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A wireless power transmission method for wirelessly transmitting power to a wireless power receiver according to the present invention, the method comprising: receiving a control error packet received from the wireless power receiver in a power transmission step; Determining whether a control error value of the control error packet is successively received below a positive first threshold value or below a first negative threshold value; Determining whether the received control error value is an absolute control error value equal to or greater than a second threshold value; Generating a second power value by reflecting a weight on the transmission power if the determined control error value has an absolute control error value equal to or greater than the second threshold value; Wherein the absolute control error value above the second threshold value is a positive or a negative maximum control error value that can be received from the wireless power receiver.

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Effects of the wireless charging apparatus and the method according to the present embodiment are as follows.

The present embodiment is advantageous in providing a wireless charging apparatus and a method thereof.

Also, the present embodiment can minimize the charging time through high-speed wireless charging.

In addition, the present embodiment can perform power transmission adaptively to the state of the wireless power receiving apparatus during high-speed wireless charging.

In addition, the present embodiment can achieve high charging efficiency while minimizing internal damage due to overvoltage or the like of the wireless power receiving apparatus during high-speed wireless charging.

Also, the present embodiment can stably control power in high-speed wireless charging.

In addition, the present embodiment can have a wider charging area by using a plurality of transmission coils, thereby increasing the power transmission efficiency and thus improving user convenience.

In addition, since the present invention can use only one of a plurality of identical circuits, the size of the wireless power transmitter itself can be reduced, and parts used can be reduced, thereby reducing the cost.

Further, the present invention can utilize the component elements defined in the published wireless power transmission standard, and can follow the already defined standard.

The effects obtained by the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those skilled in the art from the following description will be.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. It is to be understood, however, that the technical features of the present invention are not limited to the specific drawings, and the features disclosed in the drawings may be combined with each other to constitute a new embodiment.
1 is a block diagram illustrating a wireless charging system according to an embodiment.
2 is a block diagram illustrating a wireless charging system according to another embodiment.
3 is a diagram for explaining a sensing signal transmission procedure in a wireless charging system according to an embodiment.
4 is a state transition diagram for explaining the wireless power transmission procedure defined in the WPC standard.
5 is a state transition diagram for explaining the wireless power transmission procedure defined in the PMA standard.
6 is a block diagram illustrating a structure of a wireless power transmitter according to an embodiment.
7 is a block diagram illustrating a structure of a wireless power receiver interworking with the wireless power transmitter according to the FIG.
8 is a diagram for explaining a modulation and demodulation method of a wireless power signal according to an embodiment.
9 is a diagram for explaining a packet format according to a wireless power transmission procedure according to an embodiment.
FIG. 10 is a diagram for explaining the types of packets that the wireless power receiving apparatus according to the embodiment of the wireless power transmission procedure can transmit in the ping stage.
11 is a diagram for explaining a message format of an identification packet according to a wireless power transmission procedure according to an embodiment.
12 is a diagram for explaining a message format of a configuration packet and a power control hold packet according to a wireless power transmission procedure according to an embodiment.
13 is a diagram for explaining a structure of a charge mode packet for requesting a charge mode change according to a wireless power transfer procedure according to an embodiment.
FIG. 14 is a diagram for explaining a type of a packet that can be transmitted in a power transmission step and a message format thereof by a wireless power receiving apparatus according to an embodiment of a wireless power transmission procedure; FIG.
15 is a diagram for explaining a packet type and a message format thereof according to a wireless power transmission procedure according to another embodiment.
16 is a charge mode state diagram for explaining the charge mode switching according to one embodiment.
17 is a diagram for explaining a wireless charging method in a wireless power transmitter according to one embodiment.
18 is a diagram for explaining a wireless charging method on a wireless charging system according to an embodiment.
19 is a diagram for explaining a power control method in a wireless power transmitter according to an embodiment.
20 is a diagram for explaining a power control method in a wireless power transmitter according to another embodiment.
21 is a diagram illustrating an example of a wireless charging system according to an embodiment.
22 is a diagram showing an example of a wireless charging system according to another embodiment.
23 and 24 are diagrams for explaining an operation state of the wireless power transmitter according to another embodiment.
25 is a diagram for explaining a power control method in a wireless power transmitter according to another embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an apparatus and various methods to which the embodiments are applied will be described in detail with reference to the drawings. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role.

The present invention is not necessarily limited to these embodiments, as long as all of the constituent elements of the embodiment are described as being combined or operated together. That is, within the scope of the present invention, all of the components may be selectively coupled to one or more of them. In addition, although all of the components may be implemented as one independent hardware, some or all of the components may be selectively combined to perform a part or all of the functions in one or a plurality of hardware. As shown in FIG. The codes and code segments constituting the computer program may be easily deduced by those skilled in the art. Such a computer program may be stored in a computer-readable storage medium, readable and executed by a computer, thereby realizing embodiments. As the storage medium of the computer program, a magnetic recording medium, an optical recording medium, a carrier wave medium, or the like may be included.

In the description of the embodiment, in the case of being described as being formed on the "upper or lower", "before" or "after" of each component, (Both below and "front EH after (rear)") are formed such that the two components are in direct contact with each other or one or more other components are disposed between the two components.

It is also to be understood that the terms such as " comprises, "" comprising," or "having ", as used herein, mean that a component can be implanted unless specifically stated to the contrary. But should be construed as including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected to or connected to the other component, It should be understood that an element may be "connected," "coupled," or "connected."

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

In the description of the embodiments, an apparatus for transmitting wireless power on a wireless power charging system includes a wireless power transmitter, a wireless power transmitter, a wireless power transmitter, a wireless power transmitter, a transmitter, a transmitter, a transmitter, , A wireless power transmission device, a wireless power transmitter, a wireless charging device, and the like. For the sake of convenience, a wireless power receiving device, a wireless power receiving device, a wireless power receiving device, a wireless power receiving device, a receiving terminal, a receiving side, a receiving device, a receiver Terminals and the like can be used in combination.

The wireless charging device according to the embodiment may be configured as a pad type, a cradle type, an access point (AP) type, a small base type, a stand type, a ceiling embedded type, a wall type, Power may be transmitted to the device.

As an example, a wireless power transmitter can be used not only on a desk or on a table, but also developed for automobiles and used in a vehicle. A wireless power transmitter installed in a vehicle can be provided in a form of a stand that can be easily and stably fixed and mounted.

A mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a PDA (Personal Digital Assistants), a PMP (Portable Multimedia Player), a navigation device, an MP3 player, The present invention can be applied to a portable electronic device such as a toothbrush, an electronic tag, a lighting device, a remote controller, a fishing rod, and the like. However, the present invention is not limited thereto. ), And the term terminal or device may be used in combination. A wireless power receiver according to another embodiment may also be mounted on a vehicle, an unmanned aerial vehicle, an air drone or the like.

A wireless power receiver according to an embodiment may include at least one wireless power transmission scheme and may receive wireless power from two or more wireless power transmitters at the same time. Here, the wireless power transmission scheme may include at least one of the electromagnetic induction scheme, the electromagnetic resonance scheme, and the RF wireless power transmission scheme. In particular, the wireless power receiving means for supporting the electromagnetic induction method may include an electromagnetic induction type wireless charging technique defined by the Wireless Power Consortium (WPC) and the AirFuel Alliance (formerly PMA, Power Matters Alliance) have. In addition, the wireless power receiving means for supporting the electromagnetic resonance method may include a resonance type wireless charging technique defined in the AirFuel Alliance (formerly Alliance for Wireless Power) standard mechanism, a wireless charging technology standard organization.

Generally, a wireless power transmitter and a wireless power receiver that constitute a wireless power system can exchange control signals or information through in-band communication or Bluetooth low energy (BLE) communication. Here, the in-band communication and the BLE communication can be performed by a pulse width modulation method, a frequency modulation method, a phase modulation method, an amplitude modulation method, an amplitude and phase modulation method, and the like. For example, the wireless power receiver can transmit various control signals and information to the wireless power transmitter by generating a feedback signal by switching on / off the current induced through the reception coil in a predetermined pattern. The information transmitted by the wireless power receiver may include various status information including received power intensity information. At this time, the wireless power transmitter can calculate the charging efficiency or the power transmission efficiency based on the received power intensity information.

1 is a block diagram illustrating a wireless charging system according to an embodiment.

Referring to FIG. 1, the wireless charging system includes a wireless power transmitter 10 for transmitting power wirelessly, a wireless power receiver 20 for receiving the transmitted power, and an electronic device 30 Lt; / RTI >

For example, the wireless power transmitting terminal 10 and the wireless power receiving terminal 20 can perform in-band communication in which information is exchanged using the same frequency band as that used for wireless power transmission. In another example, the wireless power transmitting terminal 10 and the wireless power receiving terminal 20 perform out-of-band communication in which information is exchanged using a different frequency band different from the operating frequency used for wireless power transmission .

For example, information exchanged between the wireless power transmitting terminal 10 and the wireless power receiving terminal 20 may include control information as well as status information of each other. Here, the status information and the control information exchanged between the transmitting and receiving end will become more apparent through the description of the embodiments to be described later.

The in-band communication and the out-of-band communication may provide bidirectional communication, but the present invention is not limited thereto. In another embodiment, the in-band communication and the out-of-band communication may be provided.

 For example, the unidirectional communication may be that the wireless power receiving terminal 20 transmits information only to the wireless power transmitting terminal 10, but the present invention is not limited thereto, and the wireless power transmitting terminal 10 may transmit information Lt; / RTI >

In the half duplex communication mode, bidirectional communication is possible between the wireless power receiving terminal 20 and the wireless power transmitting terminal 10, but information can be transmitted only by any one device at any time.

The wireless power receiving terminal 20 according to an exemplary embodiment may acquire various status information of the electronic device 30. [ For example, the status information of the electronic device 30 may include current power usage information, information for identifying a running application, CPU usage information, battery charge status information, battery output voltage / current information, And is information obtainable from the electronic device 30 and available for wireless power control.

In particular, the wireless power transmitting terminal 10 according to an exemplary embodiment may transmit a predetermined packet indicating whether or not to support fast charging to the wireless power receiving terminal 20. The wireless power receiving terminal 20 can inform the electronic device 30 that the connected wireless power transmitting terminal 10 is confirmed to support the fast charging mode. The electronic device 30 can indicate that the high-speed charging is possible through the predetermined display means provided, for example, the number of liquid crystal displays.

Also, the user of the electronic device 30 may select the predetermined fast charge request button displayed on the display means to control the wireless power transmitting terminal 10 to operate in the fast charge mode. In this case, the electronic device 30 may transmit a predetermined fast charge request signal to the wireless power receiving terminal 20 when the quick charge request button is selected by the user. The wireless power receiving terminal 20 can generate a charging mode packet corresponding to the received fast charging request signal and transmit it to the wireless power transmitting terminal 10 to execute the fast charging mode.

Also, the electronic device 30 can be operated and switched to the fast charge mode automatically according to the result of communication and negotiation between the wireless power transmitter 10 and the wireless power receiver 20, without the user's request or input. The electronic device 30 can also be operated and switched to a general low power mode automatically according to the result of communication and negotiation between the wireless power transmitter 10 and the wireless power receiver 20 without the user's request or input.

In addition, the wireless power transmitter 10 may collect status information of the receiver from the wireless power receiver 20 when operating in a fast charge mode and may control power transmitted in accordance with the fast charge mode, based on the status information have.

2 is a block diagram illustrating a wireless charging system according to another embodiment.

For example, as shown in 200a, the wireless power receiving terminal 20 may be composed of a plurality of wireless power receiving devices, and a plurality of wireless power receiving devices are connected to one wireless power transmitting terminal 10, . At this time, the wireless power transmission terminal 10 can distribute power to a plurality of wireless power reception devices in a time division manner, but the wireless power transmission terminal 10 is not limited thereto. For example, in the wireless power transmission terminal 10, Power can be distributed and transmitted to a plurality of wireless power receiving apparatuses using a frequency band.

Wherein the number of wireless power receiving devices connectable to a single wireless power receiving device is adaptive based on at least one of the required power for each wireless power receiving device, the battery charging status, the power consumption of the electronic device, and the available power of the wireless power transmitting device . ≪ / RTI >

As another example, as shown in FIG. 200B, the wireless power transmission terminal 10 may be configured with a plurality of wireless power transmission devices. In this case, the wireless power receiving terminal 20 may be connected to a plurality of wireless power transmission devices at the same time, and may simultaneously receive power from connected wireless power transmission devices to perform charging. At this time, the number of wireless power transmission devices connected to the wireless power receiving terminal 20 is adaptively determined based on the required power of the wireless power receiving terminal 20, the battery charging state, the power consumption amount of the electronic device, the available power of the wireless power transmission device, It is possible.

3 is a diagram for explaining a sensing signal transmission procedure in a wireless charging system according to an embodiment.

As an example, the wireless power transmitter may be equipped with three transmit coils 111, 112, 113. Each transmit coil may overlap a portion of the transmit coil with a different transmit coil, and the wireless power transmitter may include a predetermined sense signal 117, 127 for sensing the presence of the wireless power receiver through each transmit coil - And sequentially transmits digital ping signals in a predefined order.

As shown in FIG. 3, the wireless power transmitter sequentially transmits the detection signal 117 through the primary sensing signal transmission procedure shown in reference numeral 110, and receives a signal strength indicator (Signal Strength Indicator 116 (or signal strength packet) may be received. Subsequently, the wireless power transmitter sequentially transmits the detection signal 127 through the secondary detection signal transmission procedure shown in the reference numeral 120, and the signal strength indicator 126 is transmitted to the transmission coils 111 and 112 It is possible to control the efficiency (or charging efficiency) - that is, the state of alignment between the transmitting coil and the receiving coil - to identify a good transmitting coil and to allow power to be transmitted through the identified transmitting coil, i. .

As shown in FIG. 3, the reason why the wireless power transmitter performs the two detection signal transmission procedures is to more accurately identify to which transmission coil the reception coil of the wireless power receiver is well aligned.

If the signal strength indicators 116 and 126 are received at the first transmission coil 111 and the second transmission coil 112 as shown in the aforementioned numerals 110 and 120 of FIG. 3, Selects a transmission coil having the best alignment based on the received signal strength indicator 126 in each of the first transmission coil 111 and the second transmission coil 112 and performs wireless charging using the selected transmission coil .

4 is a state transition diagram for explaining the wireless power transmission procedure defined in the WPC standard.

Referring to FIG. 4, power transmission from a transmitter to a receiver according to an embodiment of the present invention includes a selection phase 410, a ping phase 420, an Identification and Configuration Phase A Negotiation Phase 440, a Calibration Phase 450, a Power Transfer Phase 460 and a Renegotiation Phase 470. In this case,

The selection step 410 includes a step of transitioning, e.g., S402, S404, S408, S410, S412, when a specific error or a specific event is detected while initiating a power transmission or maintaining a power transmission . Here, the specific error and the specific event will become clear through the following description. Also, in a selection step 410, the transmitter may monitor whether an object is present on the interface surface. If the transmitter detects that an object has been placed on the interface surface, it can transition to the zipping step 420. In the selection step 410, the transmitter transmits an analog ping signal of a very short pulse and, based on the current change of the transmission coil or the primary coil, It is possible to detect whether or not there is an error.

When an object is sensed in the selection step 410, the wireless power transmitter may measure the quality factor of the wireless power resonant circuit, e.g., the transmit coil and / or the resonant capacitor for wireless power transmission.

 A wireless power transmitter may measure the inductance of a wireless power resonant circuit (e.g., a power transfer coil and / or a resonant capacitor).

The detailed measurement method will be explained in the other drawings instead.

The quality factor and / or inductance may be used in future negotiation step 440 to determine whether a foreign object is present.

In step 420, the transmitter wakes up the receiver and transmits a digital ping to identify whether the detected object is a wireless power receiver (S401). If the sender does not receive a response signal to the digital ping (e. G., A signal strength packet) from the receiver at step 420, then the receiver may transition back to step 410 again. If the transmitter receives a signal indicating completion of power transmission from the receiver, that is, a charge completion packet, the transmitter may transition to the selection step 410 (S402).

Once the ping stage 420 is complete, the transmitter may transition to an identification and configuration step 430 for identifying the receiver and collecting receiver configuration and status information (S403).

In the identifying and configuring step 430, the sender may determine whether the packet is unexpected, whether a desired packet is received during a predefined period of time (time out), a packet transmission error (transmission error) (No power transfer contract), the process may proceed to the selection step 410 (S404).

The transmitter may determine whether an entry to the negotiation step 440 is necessary based on the negotiation field value of the configuration packet received in the identification and configuration step 430. [

As a result of checking, if a negotiation is required, the transmitter may enter the negotiation step 440 (S405). In the negotiation step 440, the transmitter may perform a predetermined FOD detection procedure.

On the other hand, if it is determined that negotiation is not required, the transmitter may directly enter the power transmission step 460 (S406).

At negotiation step 440, the sender may receive a Foreign Object Detection (FOD) status packet including a reference quality factor value. Or a FOD state packet including a reference inductance value. Or a status packet including a reference quality factor value and a reference inductance value. At this time, the transmitter can determine a quality factor threshold for FO detection based on the reference quality factor value. The transmitter can determine the inductance threshold for FO detection based on the reference inductance value.

The transmitter can detect whether there is an FO in the fill area using the quality factor threshold for the determined FO detection and the currently measured quality factor value, e.g., the quality factor value measured prior to the ping step, Power transmission can be controlled according to the detection result. As an example, if FO is detected, power transmission may be interrupted, but is not limited to this.

The transmitter can detect whether there is an FO in the charging region using the inductance threshold for the determined FO detection and the currently measured inductance value - e.g., the inductance value measured before the ping phase - The power transmission can be controlled. As an example, if FO is detected, power transmission may be interrupted, but is not limited to this.

If FO is detected, the transmitter may return to selection step 410 (S408). On the other hand, if no FO is detected, the transmitter may enter the power transfer step 460 via the correction step 450 (S407 and S409). In detail, if the FO is not detected, the transmitter determines the strength of the power received at the receiving end in the calibrating step 450 and the power loss at the receiving end and the transmitting end to determine the strength of the power transmitted at the transmitting end Can be measured. That is, the transmitter can estimate the power loss based on the difference between the transmit power of the transmitting end and the receiving power of the receiving end in the correcting step 450. A transmitter according to one embodiment may compensate the threshold for FOD detection by reflecting the predicted power loss.

In the power transfer step 460, the transmitter determines whether an unexpected packet is received, a desired packet is received during a predefined period of time (time out), a violation of a predetermined power transmission contract occurs transfer contract violation, and if the charging is completed, the selection step 410 can be performed (S410).

Also, in the power transfer step 460, if the transmitter needs to reconfigure the power transfer contract according to changes in the transmitter state, etc., it may transition to the renegotiation step 470 (S411). At this time, if the renegotiation is normally completed, the transmitter may return to the power transmission step 460 (S413).

The power transmission contract may be set based on the status and characteristic information of the transmitter and the receiver. For example, the transmitter status information may include information on the maximum amount of transmittable power, information on the maximum number of receivable receivers, and the receiver status information may include information on the requested power and the like.

If the renegotiation is not normally completed, the transmitter stops transmitting power to the receiver and may transition to a selection step (S412).

5 is a state transition diagram for explaining the wireless power transmission procedure defined in the PMA standard.

Referring to FIG. 5, power transmission from a transmitter to a receiver according to the PMA standard is largely divided into a standby phase 510, a digital ping phase 520, an identification phase 530, A Power Transfer Phase 540, and an End of Charge Phase 550. FIG.

The waiting step 510 may be a step of performing a receiver identification procedure for power transmission or transitioning to a specific error or a specific event while sensing a power transmission. Here, the specific error and the specific event will become clear through the following description. Also, at a standby step 510, the transmitter may monitor whether an object is present on the Charging Surface. If the transmitter detects that an object has been placed on the charging surface, or if an RXID retry is in progress, the digital switching may proceed to step 520 (S501). Here, RXID is a unique identifier assigned to a PMA compatible receiver. At the standby step 510, the transmitter transmits an analog ping of a very short pulse and, based on the change in current of the transmitting coil, causes the object to move to the active surface of the interface surface-for example, It can be detected whether or not it exists.

The transmitter transited to the digital pinging step 520 sends a digital finger signal to identify whether the sensed object is a PMA compatible receiver. When sufficient power is supplied to the receiver by the digital ping signal transmitted by the transmitter, the receiver can modulate the received digital ping signal according to the PMA communication protocol and transmit a predetermined response signal to the transmitter. Here, the response signal may include a signal strength indicator indicating the strength of the power received at the receiver. At step 520, the transmitter may transition to the identifying step 530 if a valid response signal is received (S502).

If the response signal is not received or it is determined that it is not a PMA compliant receiver, i.e., it is a Foreign Object Detection (FOD), at step 520, the transmitter can transition to the wait step 510 (S503). As an example, a foreign object (FO) may be a metallic object including coins, keys, and the like.

In the identifying step 530, the transmitter may transition to the wait step 510 if the receiver identification procedure fails or the receiver identification procedure must be re-performed and the receiver identification procedure has not been completed for a predefined period of time S504).

If the transmitter succeeds in identifying the receiver, the transmitter may transition from the identifying step 530 to the power transfer step 540 and start charging (S505).

In the power transfer step 540, the transmitter determines if the desired signal is not received within a predetermined time (Time Out), an FO is detected, or if the voltage of the transmit coil exceeds a predefined reference value, (S506).

Also, in the power transmission step 540, if the temperature sensed by the temperature sensor provided inside the transmitter exceeds a predetermined reference value, the transmitter may transition to the completion of charging step 550 (S507).

In the charge completion step 550, if the transmitter is confirmed that the receiver has been removed from the charging surface, the transmitter can transition to the standby state 510 (S509).

If the measured temperature drops below the reference value in the over temperature state, the transmitter may transition from the charging completion step 550 to the digital charging step 520 in step S510.

In the digital ping phase 520 or the power transfer phase 540, the transmitter may transition to the charge completion phase 550 (S508 and S511) when an End Of Charge (EOC) request is received from the receiver.

6 is a block diagram illustrating a structure of a wireless power transmitter according to an embodiment.

6, the wireless power transmitter 600 may include a power conversion unit 610, a power transmission unit 620, a communication unit 630, a control unit 640, and a sensing unit 650 . It should be noted that the configuration of the wireless power transmitter 600 described above is not necessarily an essential configuration, and may be configured to include more or less components.

As shown in FIG. 6, when the power is supplied from the power supply unit 660, the power conversion unit 610 may convert the power to a predetermined intensity.

For this, the power conversion unit 610 may include a DC / DC conversion unit 611 and an amplifier 612.

The DC / DC converting unit 611 may convert DC power supplied from the power supply unit 660 into DC power having a specific intensity according to a control signal of the controller 640.

At this time, the sensing unit 650 receives the DC-converted power voltage. Current, and the like to the control unit 640. Also, the sensing unit 650 may measure the internal temperature of the wireless power transmitter 600 for determining whether the overheating occurs, and may provide the measurement result to the controller 640. For example, the control unit 640 may adaptively cut off power supply from the power supply unit 650 or block power supply to the amplifier 612 based on the voltage / current value measured by the sensing unit 650 . To this end, a power cutoff circuit may be further provided at one side of the power conversion unit 610 to cut off power supplied from the power supply unit 650 or to cut off power supplied to the amplifier 612.

Also, the controller 640 may control the power supplied from the wireless power transmitter 600 to the wireless power receiver adaptively based on the voltage / current value measured by the sensing unit 650. For this, the control unit 640 weights the power value transmitted from the wireless power transmitter 600 to the wireless power receiver based on the state information of the receiver received from the wireless power receiver to sequentially increase or decrease the power to supply or reduce the power .

The amplifier 612 can adjust the intensity of the DC / DC-converted power according to the control signal of the controller 640. For example, the control unit 640 may receive the power reception status information and / or the power control signal of the wireless power receiver through the communication unit 630 and may receive the power control information based on the received power reception status information and / So that the amplification factor of the amplifier 612 can be dynamically adjusted. For example, the power reception status information may include, but is not limited to, the intensity information of the rectifier output voltage, the intensity information of the current applied to the reception coil, and the like. The power control signal may include a signal for requesting power increase, a signal for requesting power reduction, and the like.

The power transmitting unit 620 may be configured to include a multiplexer 621 (or a multiplexer), a transmitting coil 622, and the like. The power transmitting unit 620 may further include a carrier generator (not shown) for generating a specific operating frequency for power transmission

The carrier generator may generate a specific frequency for converting the output DC power of the amplifier 612 delivered via the multiplexer 621 to AC power having a specific frequency. In the above description, the AC signal generated by the carrier generator is mixed with the output of the multiplexer 621 to generate AC power. However, this is merely one embodiment, It should be noted that they may be mixed in later stages.

The power transmission unit 620 includes a multiplexer 621 and a plurality of transmission coils 622, i.e., first to n-th transmission coils, for controlling the output power of the amplifier 612 to be transmitted to the transmission coil .

The controller 640 according to an exemplary embodiment may transmit power by time division multiplexing for each transmission coil when a plurality of wireless power receivers are connected. For example, if three radio power receivers-i. E., First through third radio power receivers-are each identified by three different transmit coils, i. E. First through third transmit coils, The control unit 640 controls the multiplexer 621 so that power can be transmitted through a specific transmission coil in a specific time slot. At this time, the amount of power transmitted to the corresponding wireless power receiver can be controlled according to the length of the time slot allocated for each transmission coil, but this is only one embodiment. The amplification factor of the amplifier 612 of the wireless power receiver may be controlled to control the transmission power of each wireless power receiver.

The control unit 641 may control the multiplexer 621 so that the detection signals can be sequentially transmitted through the first through n'th transmission coils 622 during the first detection signal transmission procedure. At this time, the control unit 640 can identify the time at which the sensing signal is transmitted using the timer 655. When the sensing signal transmission time arrives, the control unit 640 controls the multiplexer 621 to transmit the sensing signal through the corresponding transmission coil Can be controlled. For example, the timer 650 may transmit a specific event signal to the control unit 640 at predetermined intervals during the ping transmission step. When the event signal is detected, the control unit 640 controls the multiplexer 621 to transmit the corresponding transmission coil So that the digital ping can be transmitted.

In addition, the control unit 640 may receive a predetermined transmission coil identifier for identifying a signal strength indicator (signal strength indicator) through a transmission coil from the demodulation unit 632 during the first detection signal transmission procedure, And receive the received signal strength indicator. In the second sensing signal sending procedure, the controller 640 controls the multiplexer 621 so that the signal strength indicator can be transmitted only through the received transmitting coil (s) during the first sensing signal sending procedure Control. In another example, when there are a plurality of transmission coils in which the signal strength indicator is received during the first transmission sensing signal transmission procedure, the control unit 640 transmits the transmission coil receiving the signal strength indicator having the largest value to the second transmission sensing signal transmission process It is determined as a transmission coil to be transmitted first, and the multiplexer 621 is controlled according to the determination result.

The modulator 631 may modulate the control signal generated by the controller 640 and transmit the modulated control signal to the multiplexer 621. Here, the modulation scheme for modulating the control signal includes a frequency shift keying (FSK) modulation scheme, a Manchester coding modulation scheme, a phase shift keying (PSK) modulation scheme, a pulse width modulation scheme, A differential bi-phase modulation method, and the like.

The demodulator 632 can demodulate the detected signal and transmit the demodulated signal to the controller 640 when a signal received through the transmission coil is detected. Here, the demodulated signal may include a signal strength indicator, an error correction (EC) indicator for power control during wireless power transmission, an end of charge indicator (EOC), an overvoltage / overcurrent / overheat indicator, But is not limited to, various status information for identifying the status of the wireless power receiver.

In addition, the demodulator 632 can identify which of the transmit coils the demodulated signal is received, and provide the controller 640 with a predetermined transmit coil identifier corresponding to the identified transmit coil.

The wireless power transmitter 600 may also transmit wireless power using the transmit coil 622 and may exchange various information with the wireless power receiver via the transmit coil 622. [ As another example, the wireless power transmitter 600 may further include a separate coil corresponding to each of the transmission coils 622 (i.e., the first to n < th > transmission coils) And perform in-band communication with the receiver.

In the description of FIG. 6, the wireless power transmitter 600 and the wireless power receiver perform in-band communication. However, the wireless power transmitter 600 and the wireless power receiver perform only in- Directional two-way communication can be performed over different frequency bands. For example, the short-range bidirectional communication may be one of low-power Bluetooth communication, RFID communication, UWB communication, and Zigbee communication.

7 is a block diagram illustrating a structure of a wireless power receiver interworking with the wireless power transmitter according to the FIG.

7, the wireless power receiver 700 includes a receiving coil 710, a rectifier 720, a DC / DC converter 730, a load 740, a sensing unit 750, 760, and a main control unit 770. Here, the communication unit 760 may include at least one of a demodulation unit 761 and a modulation unit 762.

Although the wireless power receiver 700 shown in the example of FIG. 7 is shown as being capable of exchanging information with the wireless power transmitter 600 through in-band communication, this is only one embodiment, The communication unit 760 according to the embodiment may provide near-end bi-directional communication through a frequency band different from the frequency band used for the transmission of the wireless power signal.

AC power received through the receive coil 710 may be delivered to the rectifier 720. The rectifier 720 may convert the AC power to DC power and transmit it to the DC / DC converter 730. [ The DC / DC converter 730 may convert the intensity of the rectifier output DC power to a specific intensity required by the load 740 and then forward it to the load 740. The receiving coil 710 may also include a plurality of receiving coils (not shown), i.e., first to n-th receiving coils. The frequency of the AC power transmitted to each of the reception coils (not shown) according to an embodiment may be different from each other, and another embodiment may include a predetermined frequency controller having a function of adjusting LC resonance characteristics for different reception coils The resonance frequencies of the respective reception coils can be set differently.

The sensing unit 750 may measure the intensity of the DC power output from the rectifier 720 and provide it to the main control unit 770. Also, the sensing unit 750 may measure the intensity of the current applied to the reception coil 710 according to the wireless power reception, and may transmit the measurement result to the main control unit 770. The sensing unit 750 may measure the internal temperature of the wireless power receiver 700 and provide the measured temperature value to the main control unit 770.

For example, the main control unit 770 may compare the measured rectifier output DC power with a predetermined reference value to determine whether an overvoltage is generated. As a result of the determination, if an overvoltage is generated, a predetermined packet indicating that the overvoltage has occurred can be generated and transmitted to the modulating unit 762. Here, the signal modulated by the modulating unit 762 may be transmitted to the wireless power transmitter through the receiving coil 710 or a separate coil (not shown). The main control unit 770 may determine that the detection signal is received when the intensity of the rectifier output DC power is equal to or greater than a predetermined reference value and when the signal strength indicator corresponding to the detection signal is received by the modulation unit 762 To be transmitted to the wireless power transmitter. The demodulation unit 761 demodulates the AC power signal between the reception coil 710 and the rectifier 720 or the DC power signal output from the rectifier 720 to identify whether or not the detection signal is received, (770). At this time, the main control unit 770 may control the signal intensity indicator corresponding to the detection signal to be transmitted through the modulation unit 762. [

The main control unit 770 may also determine whether the connected radio power transmitter is a wireless power transmitter capable of fast charging based on the information demodulated by the demodulator 760. [

The main control unit 770 may compare the internal temperature measured by the sensing unit 750 with a predetermined reference value to determine whether overheating occurs. If overheating occurs during fast charging, the main control unit 770 may generate and transmit a packet for requesting power control to the wireless power transmitter.

Also, the main control unit 770 determines whether the change of the charge state or the change of the charge mode is required based on at least one of the battery charge rate, the internal temperature, the intensity of the rectifier output voltage, the CPU usage rate mounted on the electronic apparatus, If it is determined that the charging state or the mode should be changed as a result of the determination, a packet including the changed state value may be generated and transmitted to the wireless power transmitter.

8 is a diagram for explaining a modulation and demodulation method of a wireless power signal according to an embodiment.

8, the wireless power transmitting terminal 10 and the wireless power receiving terminal 20 can encode or decode a packet to be transmitted based on an internal clock signal having the same period.

Hereinafter, a method of encoding a packet to be transmitted will be described in detail with reference to FIGS. 1 to 8. FIG.

1, when the wireless power transmitting terminal 10 or the wireless power receiving terminal 20 does not transmit a specific packet, the wireless power signal is not modulated with a specific frequency as shown in reference numeral 41 in FIG. 1 It can be an alternating current. On the other hand, when the wireless power transmitting terminal 10 or the wireless power receiving terminal 20 transmits a specific packet, the wireless power signal may be an AC signal modulated by a specific modulation method as shown in reference numeral 42 in FIG. For example, the modulation scheme may include, but is not limited to, an amplitude modulation scheme, a frequency modulation scheme, a frequency and amplitude modulation scheme, a phase modulation scheme, and the like.

The binary data of the packet generated by the wireless power transmitting terminal 10 or the wireless power receiving terminal 20 may be subjected to differential bi-phase encoding as shown in 820. [ Specifically, the differential two-stage encoding has two state transitions to encode data bit one and one state transition to encode data bit zero. 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.

The encoded binary data may be subjected to a byte encoding scheme, as shown in FIG. Referring to reference numeral 830, a byte encoding method according to an embodiment of the present invention includes a start bit and a stop bit for identifying a start and a type of a bitstream of an 8-bit encoded binary bitstream, , And a parity bit for detecting whether or not an error has occurred in the bitstream (byte).

9 is a diagram for explaining a packet format according to an embodiment.

Referring to FIG. 9, a packet format 900 used for information exchange between the wireless power transmitter 10 and the wireless power receiver 20 includes information for acquiring synchronization for demodulating the packet and identifying an accurate start bit of the packet A header 920 for identifying a type of a message included in the packet, a message 930 for transmitting contents of the packet (or a payload), a preamble field 910, And a checksum field 940 for identifying whether or not an error has occurred in the packet.

As shown in FIG. 9, the packet receiving end may identify the size of the message 930 included in the packet based on the header 920 value.

In addition, the header 920 may be transmitted before each step of the wireless power transmission procedure, and some header 920 values may be defined as different types of messages even though they are the same in different steps. For example, referring to FIG. 9, a header value corresponding to an end power transfer in the ping phase and an end of power transmission in the power transfer phase may be equal to 0x02.

The message 930 includes data to be transmitted at the transmitting end of the packet. As an example, the data contained in the message 930 field is a report to the other party. A request or response may be, but is not limited to, a response.

The packet 9000 according to another exemplary embodiment may further include at least one of a transmitting end identification information for identifying a transmitting end that transmitted the packet and a receiving end identifying information for identifying a receiving end to receive the packet. Here, the information may include the transmitting end identification information, the receiving end identification basic IP address information, the MAC address information, the product identification information, and the like, but it is not limited thereto and information that can distinguish the receiving end and the transmitting end on the wireless system is sufficient.

The packet 900 according to another embodiment may further include predetermined group identification information for identifying a corresponding receiving group when the packet is to be received by a plurality of apparatuses.

10 is a view for explaining the types of packets that the wireless power receiving apparatus according to an embodiment can transmit in the ping step.

10, the wireless power receiving apparatus can transmit a signal strength packet or a power transmission stop packet in the step of pinging.

Referring to FIG. 10, the message format of a signal strength packet according to an exemplary embodiment may include a signal strength value having a size of 1 byte. The signal strength value may indicate a degree of coupling between the transmitting coil and the receiving coil, and may be calculated based on the rectifier output voltage in the digital ping section, the open circuit voltage measured in the output blocking switch, Lt; / RTI > The signal strength value may range from a minimum of 0 to a maximum of 255, and may have a value of 255 if the actual measured value for a particular variable is equal to the maximum value of the variable (Umax).

For example, the signal strength value may be calculated as U / Umax * 256.

Referring to FIG. 10, the message format of the power transmission stop packet according to an exemplary embodiment may include an end power transfer code having a size of 1 byte.

The reasons why the wireless power receiving apparatus requests the wireless power transmitter to stop the power transmission include charging completion, internal fault, overtemperature, overvoltage, overcurrent, battery But is not limited to, battery failure, reconfiguration and no response, noise current, and the like. It should be noted that the power transmission interruption code may be further defined in response to each new power transmission interruption reason.

Charging complete can be used to indicate that the charging of the receiver battery is complete. Internal errors can be used when a software or logical error in the internal operation of the receiver is detected.

Overheating / overvoltage / overcurrent can be used when the measured temperature / voltage / current value at the receiver exceeds the defined threshold for each.

Battery damage can be used if it is determined that there is a problem with the receiver battery.

Reconfiguration can be used when renegotiation is required for power transmission conditions.

No response can be used if the transmitter's response to the control error packet - meaning increasing or decreasing the strength of the power - is judged to be unhealthy.

The noise current, which is different from the overcurrent, can be used when the noise current value measured at the receiver exceeds the defined threshold value due to switching noise in the inverter.

11 is a diagram for explaining a message format of an identification packet according to an embodiment.

11, the message format of the identification packet includes a Version Information field, a Manufacturer Information field, an Extension Indicator field, and a Basic Device Identification Information field Lt; / RTI >

In the version information field, revision version information of a standard applied to the wireless power receiving apparatus can be recorded.

In the manufacturer information field, a predetermined identification code for identifying the manufacturer of the wireless power receiving apparatus may be recorded.

The extension indicator field may be an indicator for identifying whether an extended identification packet including the extended device identification information exists. For example, if the value of the extension indicator is 0, it means that there is no extension identification packet, and if the extension indicator value is 1, it means that the extension identification packet exists after the identification packet.

Referring to reference numerals 1101 to 1102, if the extension indicator value is 0, the device identifier for the corresponding wireless power receiver may be a combination of manufacturer information and basic device identification information. On the other hand, if the extension indicator value is 1, the device identifier for the wireless power receiver may be a combination of manufacturer information, basic device identification information, and extended device identification information.

12 is a diagram for explaining a message format of a configuration packet and a power control hold packet according to an embodiment.

12, the message format of the configuration packet may have a length of 5 bytes and may include a power class field, a maximum power field, a power control field, A count field, a window size field, a window offset field, and the like.

The power rating field may record the power rating assigned to the wireless power receiver.

The maximum power field may record the intensity value of the maximum power that can be provided at the rectifier output of the wireless power receiver.

For example, when the power level is a and the maximum power is b, the maximum power Pmax desired to be provided at the rectifier output of the wireless power receiving apparatus can be calculated as (b / 2) * 10a.

The power control field can be used to indicate which algorithm should be used to control the power in the wireless power transmitter. For example, if the power control field value is 0, it implies applying the power control algorithm defined in the standard, and if the power control field value is 1, it means that the power control is performed according to the algorithm defined by the manufacturer.

The count field may be used to record the number of option configuration packets that the wireless power receiving device will send in the identification and configuration phase.

The window size field may be used to record the window size for calculating the average received power. As an example, the window size may be a positive integer value that is greater than zero and has a unit of 4 ms.

In the window offset field, information for identifying the time from the end of the average reception power calculation window to the transmission start point of the next received power packet may be recorded. In one example, the window offset may be a positive integer value greater than zero and in units of 4 ms.

Referring to reference numeral 1202, the message format of the power control hold packet may be configured to include a power control hold time (T_delay). A plurality of power control hold packets may be transmitted during the identification and configuration phase. For example, up to seven power control pending packets may be transmitted. The power control hold time (T_delay) may have a value between a predefined power control hold minimum time (T_min: 5 ms) and a power control hold maximum time (T_max: 205 ms). The wireless power transmission apparatus can perform power control using the power control retention time of the power control retention packet last received in the identification and configuration step. Also, the wireless power transmission apparatus can use the T_min value as the T_delay value when the power control hold packet is not received in the identification and configuration step.

The power control retention time may refer to the time that the wireless power transmission apparatus should wait without performing the power control before performing the actual power control after receiving the latest control error packet.

13 is a diagram illustrating a structure of a charge mode packet for requesting a charge mode change according to an embodiment.

Referring to FIG. 13, the header value of the charge mode packet may be one of the undefined values of the packet header values defined in the current wireless charge standard. For example, the header value of the charge mode packet may be defined as 0x18, as shown in FIG. 9, but it should be noted that this is not necessarily the value for convenience of explanation.

The message size corresponding to the header value 0x18 may be one byte.

Information on the charging mode to be changed may be recorded in the message field of the charging mode packet. For example, referring to reference numeral 1350, when a change to a fast charge mode is required in a normal low power charge mode, the wireless power receiver may transmit 0xff in the message field of the charge mode packet. On the other hand, when the fast power charging mode requires changing to the normal low power charging mode during charging, the wireless power receiver can transmit 0x00 in the message field of the charging mode packet and transmit it. The example shown in FIG. 1350 is intended to facilitate understanding of the present invention, but the message value is not necessarily so defined.

FIG. 14 is a diagram for explaining a type of a packet that can be transmitted in a power transmission step and a message format thereof by a wireless power receiving apparatus according to an embodiment of a wireless power transmission procedure; FIG.

Referring to FIG. 14, in a power transmission step, a packet that can be transmitted by the wireless power receiving apparatus includes a control error packet (CEP), an end power transfer packet, a received power packet, A Charge Status Packet, a packet defined by the manufacturer, and the like.

Reference numeral 1401 denotes a message format of a control error packet composed of a 1-byte control error value. Here, the control error value may be an integer value ranging from -128 to +127. If the control error value is negative, the transmission power of the wireless power transmission apparatus decreases, and if it is positive, the transmission power of the wireless power transmission apparatus can rise. If the control error value is 0, the transmit power of the wireless power transmitting apparatus may not go up or down. In particular, a control error packet (CEP) with a control error value of zero may be referred to as a stable control error packet. On the other hand, if the control error value is -1 or 1, the transmission power of the wireless power transmission apparatus may not increase or decrease. That is, if a critical range is set based on the control error value 0 and a control error value within the critical range is detected, it can be defined as a stable control error packet. This is not limited and may vary depending on the setting reference.

Further, the control error value -128 to +127 can be classified into a predetermined range, and the degree of increase and decrease of the transmission power can be made different according to the classified range. Particularly, in this embodiment, it is possible to control the increase and decrease of the transmission power based on the reference values including the control error value, by reflecting the weight value.

Reference numeral 1402 denotes a message format of an End Power Transfer Packet composed of a 1-byte End Power Transfer Code.

Reference numeral 1403 denotes a received power packet of a received power packet including a 1-byte received power value. Here, the received power value may correspond to the average rectifier received power value calculated during a predetermined period. The actually received power (Received) can be calculated based on the maximum power and the power class included in the configuration packet 1201. [ As an example, the actual received power may be calculated by (received power value / 128) * (maximum power / 2) * (10 power rating).

Reference numeral 1404 denotes a message format of a Charge Status Packet consisting of a Charge Status Value of a byte. The charge state value may indicate the battery charge amount of the wireless power receiving device. For example, the charge state value 0 means a completely discharged state, the charge state value 50 may mean a 50% charge state, and the charge state value 100 may mean a full charge state. If the wireless power receiving device does not include a rechargeable battery or can not provide charge state information, the charge state value may be set to OxFF.

15 is a diagram for explaining a packet type and a message format thereof according to a wireless power transmission procedure according to another embodiment.

As shown in FIG. 15, the message field may include a transmit power weight 1501.

Here, the transmission power weight 1501 may be defined as a predetermined value reflected in the received power value included in the received power packet when the wireless power transmitter receives the received power packet from the wireless power receiver.

Specifically, the wireless power transmitter collects receiver status information including a received power packet, a control error packet, a charge status value, etc. received from the wireless power receiver, and transmits the reduced power based on the collected status information To be transmitted. That is, in the embodiment, the wireless power transmitter may detect a case where the charging state of the wireless power receiver is changed based on the receiver state information, and transmit the reflected transmission power value by reflecting the weight value.

The transmission power weight may be reflected in the transmission power for a predetermined application time or may be applied until the target power is reached. Where the transmit power weighting time or target power may be predefined or determined by the wireless power receiver and then delivered to the wireless power transmitter.

The transmission power weight can be defined as a value between 0 and 2 inclusive. For example, if the transmission power weight is 1, the wireless power transmitter maintains the received power value of the received power packet to perform the power transmission.

On the other hand, when the transmission power weight value is smaller than 1, the wireless power transmitter generates a reception power value lower than the reception power value of the received power packet. Thereafter, the weight value is reflected and the power value generated at a low level can be transmitted to the wireless power receiver. At this time, the transmission power weight can be defined as a specified value. Or a value corresponding to a control error packet, a power loss, or the like.

On the other hand, when the transmission power weight value is larger than 1, the wireless power transmitter generates a reception power value at a level higher than the reception power value of the received power packet. Thereafter, the weight value is reflected and the power value generated at a high level can be transmitted to the wireless power receiver. At this time, the transmission power weight can be defined as a specific value. And may be defined as a value corresponding to a control error packet, a power loss, and the like.

The transmission power weight is not limited to the above example and may be variously set according to the environment of the power transmission condition.

16 is a charge mode state diagram for explaining the charge mode switching according to one embodiment.

Referring to FIG. 16, the power transmission steps 440 and 540 of FIGS. 4 and 5 may include a first charging mode 1610 in which general low-power charging is performed and a second charging mode 1620 in which fast charging is performed. have.

The first charging mode 1610 and the second charging mode 1620 can be switched to each other when a predetermined condition is satisfied. In one example, the wireless power receiver requests the wireless power transmitter to switch to the second charging mode 1620 when a request to switch from the electronic device to the second charging mode 1720 is received during charging in the first charging mode 1610 The charging mode can be changed by transmitting a predetermined packet. In another example, the wireless power receiver may send a predetermined packet to the wireless power transmitter requesting a switch to the first charging mode 1610 when the battery charge level reaches a predetermined threshold during charging to the second charging mode 1620. [

A wireless power transmitter in accordance with another embodiment may transmit power to a plurality of wireless power receivers. In this case, if the wireless power receiver is newly connected or disconnected from the existing wireless power receiver, it may perform the power redistribution procedure for the currently connected wireless power receiver (s). If the power redistribution is no longer able to provide fast charging to the wireless power receiver being recharged in the second charging mode, the wireless power transmitter will cause the corresponding wireless power receiver to enter the first charging mode 1620 in the second charging mode 1620 1610). ≪ / RTI >

In the above embodiment, the charging mode is divided into the first charging mode 1610 and the second charging mode 1620. However, this is an example only, and a new charging mode , Not shown) may be defined and added.

For example, the second charging mode 1620 for fast charging may be subdivided into an intermediate power fast charging mode (not shown) and a high power fast charging mode (not shown). For example, an intermediate power fast-charge mode (not shown) can transmit an average of 9W of power. The high power fast charge mode (not shown) can transmit an average of 15W of power. The present invention is not limited to the above example, and the intermediate power fast charge mode (not shown) and the high power fast charge mode (not shown) may be defined in other meanings.

The initial charging mode according to one embodiment may be determined through state information exchange or negotiation between the wireless power transmitter and the wireless power receiver in the identifying and configuring step 430 of FIG. 4 or the identifying step 530 of FIG. 5 It is possible.

For example, in the identifying and configuring step 430 of FIG. 4 or the identifying step 530 of FIG. 5, the wireless power transmitter may transmit predetermined information to identify whether it is a device capable of fast charge mode support, To the receiver. At this time, the wireless power receiver can transmit a predetermined packet requesting fast charging to the wireless power transmitter when the wireless power receiver is a device capable of high-speed charging and the battery charging amount is less than a predetermined reference value. When the wireless power transmitter normally enters the power transmission step, it can switch to the fast charge mode at the request of the wireless power receiver to perform wireless charging.

The initial charging mode according to another embodiment may be determined in the power transmission step. As an example, the wireless power transmitter may enter a power transfer phase and transmit a first power control request packet (e.g., but not limited to a Control Error Packet defined in the WPC standard) It is possible to transmit a first packet for identifying whether to support charging. When the wireless power receiver receives the first packet and it is confirmed that the connected wireless power transmitter supports fast charging, it determines whether the fast charging is started, and transmits a predetermined first response packet including the determination result to the wireless power transmitter . That is, the initial charge mode may be determined based on the first response packet.

17 is a diagram for explaining a wireless charging method in a wireless power transmitter according to one embodiment.

Referring to FIG. 17, a wireless power transmitter collects status information of a wireless power receiver upon entering a power transmission step. Specifically, the wireless power transmitter can acquire status information including information on the power received in the power transmitting step and the status of the receiver received from the wireless power receiver (S1701)

The wireless power transmitter can check status information of the collected wireless power receiver (S1702)

The wireless power transmitter can determine whether transmission power control is necessary based on the collected status information of the wireless power receiver (S1703)

For example. The state information received from the wireless power receiver may include a repair power packet, a control error packet, a charge state value, and the like. It is not limited thereto and various types of data packets capable of notifying the state of the power transmission in the power transmission step may be included.

The received power packet may include information on received power for power transmitted from the wireless power transmitter.

The control error packet may include information that includes a control error value for the wireless power receiver to request an increase or decrease in power upon receiving power.

The charge state value may include a value that indicates the degree of charge of the battery that the wireless power receiver is charged upon receiving power.

Particularly, in this embodiment, the wireless power transmitter can control the transmission power based on the received power packet and the control error packet received from the wireless power receiver. That is, the wireless power transmitter can check whether the position of the wireless power receiver is variable based on the received power packet and the control error packet received from the wireless power receiver, and transmit the increased or decreased transmission power according to the confirmation result . Particularly, when the transmission power is increased or decreased, the weight is reflected, and the values for the increased power and the reduced power amount can be defined and controlled differently. The transmission power control operation will be described in detail below with reference to FIGS. 19 and 20. FIG.

If it is determined that the transmission power control is required based on the state information received from the wireless power receiver as in step 1703, the wireless power transmitter may increase or decrease the transmission power value by reflecting the weight based on the determination result. (S1704)

That is, the wireless power transmitter may reflect the weight of the transmit power based on the state information including the power loss and control error value received from the wireless power receiver, and may reduce or increase the transmit power. At this time, the weight for reducing the transmission power may have a higher weight than the weight for increasing the transmission power. Therefore, the power reduced based on a predetermined time can be defined to be higher than the power increased.

The wireless power transmitter can transmit power to the wireless power receiver with the above-described controlled transmission power (S1705)

18 is a diagram for explaining a wireless charging method on a wireless charging system according to an embodiment.

Referring to Fig. 18, the wireless power transmitter 1810 transitions from the identification and configuration phase to the power transfer phase. Wireless power transmitter 1810 may receive status information from wireless power receiver 1820. (S1801 through S1803)

The wireless power transmitter 1810 may receive received power packets at regular intervals from the wireless power receiver 1820. S1801 The wireless power transmitter 1810 may transmit the received power packets to the wireless power transmitter 1810 based on the received power packets. Information on the power received by the wireless power receiver 1820 can be confirmed. That is, the wireless power transmitter 1810 can check the power loss based on the received power packet. For example, the received power packet may be received at a time interval of 4000 ms or less. For example, receive power packets may be received at 1500 ms intervals.

The wireless power transmitter 1810 may receive control error packets at regular intervals from the wireless power receiver 1820. S1802 The wireless power transmitter 1810 may check the control error value contained in the control error packet. The control error value may be defined as a positive value from a negative value as described above. Accordingly, the wireless power transmitter 1810 may control the power transmitted to the wireless power receiver 1820 in accordance with the control error value. For example, control error packets can be received at time intervals of less than 350 ms. For example, control all packets can be received at 250 ms intervals.

The wireless power transmitter 1810 may receive a charge state value at regular intervals from the wireless power receiver 1820. S1803 The wireless power transmitter 1810 may be configured to charge the wireless power receiver 1820 based on the transmitted power, It is possible to obtain the charge state value including the charge state information of the battery to be charged.

The wireless power transmitter 1810 can acquire the reception state information from the wireless power receiver 1820 and control the transmission power based on the acquired state information as described above (S1804). Specifically, the transmission power control And the weight is reflected in the power level being transmitted based on the received status information. The weight may be defined as a predetermined value for increasing or decreasing the transmission power based on the state information.

The wireless power transmitter 1810 may apply a weight that is reflected to the transmission power in the transmission power control and may perform the power transmission with the power to which the weight is applied (S1805)

In the present embodiment, the wireless power transmitter 1810 has received status information received from the wireless power receiver 1820 in the order of a received power packet, a control error packet, and a charge status value. However, the reception order of the packets included in the status information may be variable, and may be executed according to the definition in the packet or packet transmission order defined in the standard.

Hereinafter, the transmission power control operation according to the present embodiment will be described in detail with reference to FIGS. 19 and 20. FIG.

19 is a diagram for explaining a power control method in a wireless power transmitter according to an embodiment.

Referring to FIG. 19, the wireless power transmitter checks status information received from a wireless power receiver (S1901). Specifically, the wireless power transmitter first determines a control error value included in the control error packet received from the wireless power receiver Can be confirmed. The wireless power transmitter checks whether the control error value of the identified control error packet is a negative value or a positive value. The wireless power transmitter can determine whether the control error value of the control error packet is a positive value (S1902)

The wireless power transmitter can determine the amount of power loss based on the received power packet when the control error value is positive (+). At this time, the wireless power transmitter can determine whether the amount of power loss is equal to or greater than the reference amount (1903)

The wireless power transmitter can generate the second power value by reflecting the first weight on the transmitted power when the power loss amount is equal to or greater than the reference amount (S1904). Specifically, the wireless power transmitter determines that the control error value is a positive value The transmission power of the wireless power transmitter is increased. It may also mean that the power transmitted from the wireless power transmitter is not received stably in the wireless power receiver if the power loss is above the reference amount. It can be defined that the alignment state of the wireless power transmitter and the wireless power receiver is not excellent. Therefore, the wireless power transmitter can increase the transmitted power by reflecting the weight. At this time, the weight reflected in the transmission power may be applied in a range of more than 0 and less than 1. Specifically, the weight for power increase can be lowered until reaching the target transmission power. That is, by slowing the rate of increase of power, it is possible to minimize the damage that can be received by the transmission power in which the electronic device is suddenly increased. At this time, the weight reflected in the transmission power can be defined as x 1/4 level of the transmission power. The weights are not limited and can be variously applied according to the embodiments.

The wireless power transmitter may transmit power to the wireless power receiver with the second power value generated by reflecting the first weight (S1905)

The wireless power transmitter can continuously receive status information while transmitting power at a second power value. In addition, the wireless power transmitter can determine whether the target power has been reached based on the reception state information (S1906)

When the wireless power transmitter determines that the target power has been reached, the power control can be terminated (S1907)

On the other hand, if the control error value of the control error packet is not a positive value as shown in reference numeral 1902, the control error value of the control error packet is negative (- ) (Step S1908). ≪ RTI ID = 0.0 >

The wireless power transmitter can determine whether the amount of power loss is less than the reference value based on the received power packet received from the wireless power receiver when the control error value is negative (S1909).

The wireless power transmitter can generate the second power value by reflecting the second weight on the transmitted power when the power loss is less than the reference amount. (S1910) Specifically, the wireless power transmitter calculates The transmission power of the wireless power transmitter is reduced. It may also mean that the power transmitted from the wireless power transmitter is being received stably in the wireless power receiver if the power loss is below the reference amount. This can be defined as an excellent alignment between the wireless power transmitter and the wireless power receiver. Therefore, the wireless power transmitter can reduce the transmitted power by reflecting the weight. At this time, the weight value reflected in the transmission power may be applied in excess of one. Specifically, the weight for reducing the power can be applied to a high level until the target transmission power is reached. That is, by accelerating the reduction rate of the power, the damage can be minimized by the power transmitted to the electronic device. At this time, the weight reflected in the transmission power can be defined as x2 level of the transmission power. The weights are not limited and can be variously applied according to the embodiments.

The wireless power transmitter may transmit power to the wireless power receiver with the second power value generated by reflecting the second weight (S1911)

The wireless power transmitter can continuously receive status information while transmitting power at a second power value. In addition, the wireless power transmitter can determine whether the target power has been reached based on the reception state information (S1906)

When the wireless power transmitter determines that the target power has been reached, the power control can be terminated.

In this embodiment, based on the state information received from the wireless power receiver, whether the control error value is a positive (+) value or negative (-) value and a predetermined weight based on power loss is applied to increase the transmission power value Or reduced.

In the present embodiment, it is explained that the control error value is a positive value or a negative value. However, if the control error value is found to be 0, 1. In this case, the transmitted power can be maintained and transmitted.

In the present embodiment, the weight reflectance is described up to the time when the target power is reached. However, the present invention is not limited to this, and the weight applying time may be defined and the weight applied during the time may be applied.

In this embodiment, the control error packet is checked and the power loss amount is checked in the following description. However, the execution order is not limited and the operation order may be changed according to the embodiment.

In the present embodiment, transmission power weights are determined based on the control error packet and the transmission power packet. However, the present invention is also applicable to an element for determining the transmission power weight, Can be reflected.

20, a power control method in a wireless power transmitter according to an embodiment different from the embodiment described in FIG. 19 will be described.

20 is a diagram for explaining a power control method in a wireless power transmitter according to another embodiment.

20, the wireless power transmitter checks the status information received from the wireless power receiver. (S2001) In detail, the wireless power transmitter first determines the control error value included in the control error packet received from the wireless power receiver Can be confirmed.

The wireless power transmitter checks whether the control error value of the identified control error packet is a negative value or a positive value. In particular, the wireless power transmitter may determine whether the control error value of the control error packet is a positive (+) N value. (S2002) The control error packet value may have a value from -128 to +127 have. Therefore, the wireless power transmitter can determine whether the value is + N when checking the control error value.

If the wireless power transmitter is identified with a control error value having a value of + N, the amount of power loss can be determined based on the received power packet. At this time, the wireless power transmitter can determine whether the power loss amount is equal to or greater than the reference amount (S2003)

The wireless power transmitter may generate the second power value by reflecting the first-M weight to the power to be transmitted when the power loss is equal to or greater than the reference amount (S2004). Specifically, the wireless power transmitter transmits the control error value or the power loss amount A plurality of weights to be applied can be defined. For example, the wireless power transmitter increases the transmission power when the control error value is + N, and the weight corresponding to the N value can be defined by checking the value of N. [ For example, the control error value having a positive value may be +1 to +127, and the control error value may be divided into M groups to define a weight corresponding to each group. That is, groups with higher control error values can define lower weights.

Accordingly, the wireless power transmitter may generate a second power value by reflecting the weight defined in the group included in the control error value received from the wireless power receiver to the transmission power. At this time, the weight reflected in the transmission power may be applied in a range of more than 0 and less than 1. Specifically, the weight for power increase can be lowered until reaching the target transmission power. In this case, by slowing the rate of increase of the power, it is possible to minimize the damage that can be incurred by the rapidly increasing transmission power of the electronic device.

The wireless power transmitter may transmit power to the wireless power receiver with the second power value generated by reflecting the first-M weight (S2005)

The wireless power transmitter can continuously receive status information while transmitting power at a second power value. Also, the wireless power transmitter can determine whether the target power has been reached based on the reception state information (S2006)

When the wireless power transmitter determines that the target power has been reached, the power control can be terminated (S2007)

On the other hand, if the control error value of the control error packet is not + N, as shown in reference numeral 2002, the wireless power transmitter determines whether the control error value of the control error packet is a -N value (S2008).

The wireless power transmitter can determine the amount of power loss based on the received power packet if it is identified as a control error value having an N value. At this time, the wireless power transmitter can determine whether the amount of power loss is less than the reference amount (S2009)

The wireless power transmitter can generate the second power value by reflecting the second-M weight to the transmitted power when the power loss is less than the reference amount (S2010). Specifically, the wireless power transmitter calculates A plurality of weights to be applied can be defined. For example, the wireless power transmitter may reduce the transmit power if the control error value is -N, where the value of N may be identified to define a weight corresponding to the N value. For example, the control error value having a negative value may be from -1 to -128, and the control error value may be divided into M groups to define a weight corresponding to each group. At this time, a group including a lower control error value can define a higher weight.

Accordingly, the wireless power transmitter may generate a second power value by reflecting the weight defined in the group included in the control error value received from the wireless power receiver to the transmission power. At this time, the weight value reflected in the transmission power may be applied in excess of one. Specifically, the weight for power reduction can be applied high until the target transmission power is reached. In this case, by accelerating the reduction rate of the power, it is possible to minimize the damage and power efficiency deterioration that can be received by the transmission power, which is rapidly lowered by the electronic device.

The wireless power transmitter may transmit power to the wireless power receiver with a second power value generated by reflecting the second-M weight (S2011)

The wireless power transmitter can continuously receive status information while transmitting power with a second power value. Also, the wireless power transmitter can determine whether the target power has been reached based on the reception state information (S2006)

The wireless power transmitter can terminate the power control when it is determined that the target power has been reached (S2007)

In this embodiment, the control error values received from the wireless power receiver are classified into M groups, and it is determined whether the control error value is + N or -N based on the status information, The weight can be applied to the transmit power to increase or decrease the transmit power value.

If the control error value is found to be 0, a weight value of 1 is applied to the transmitted power. In this case, the transmitted power can be maintained and transmitted.

For example, -1 to + 1-control error values included within a predetermined range based on the control error value 0 may be applied with a weight of 1 as the control error value 0.

In the present embodiment, the weight reflectance is described up to the time when the target power is reached. However, the present invention is not limited to this, and the weight applying time may be defined and the weight applied during the time may be applied.

In this embodiment, the control error packet is checked and the power loss amount is checked in the following description. However, the execution order is not limited and the operation order may be changed according to the embodiment.

In the present embodiment, transmission power weights are determined based on the control error packet and the transmission power packet. However, the present invention is also applicable to an element for determining the transmission power weight, Can be reflected.

21 is a diagram illustrating an example of a wireless charging system according to an embodiment.

Referring to FIG. 21, (a) the wireless power transmitter 2101 may be executed in an aligned state when performing power transmission to an electronic device including a wireless power receiver 2102, as shown in the illustration. However, (b) when the electronic device 2102 is moved to an arbitrary position by an external influence or the like as in the example (a), the power transmission efficiency may be lower than the alignment state of the example. In this case, the power loss may be increased or the control error value of the control error packet may be variable. As described above, according to the present embodiment, it is possible to control power transmitted in response to a change in the position of the electronic device so as to minimize damage to the electronic device while maintaining power transmission efficiency in the variable electronic device.

FIG. 22 is a diagram illustrating an example of a wireless charging system according to another embodiment, and FIG. 23 is a diagram for explaining an operation state of a wireless power transmitter according to another embodiment.

22 and 23, an example of FIG. 22A is an example of a case where a power transmission operation for transmitting power from a wireless power transmitter 2201 to an electronic device including a wireless power receiver 2202 is being executed . In particular, as shown in the exemplary illustration, the wireless power transmitter 2201 may be configured to determine whether the alignment of the electronic device and the wireless power transmitter 2201 by an external force, such as user carelessness during power transmission to the wireless power receiver 2202, And the case of change. In particular, when the electronic device moves to the outside of the wireless power transmitter 2201, the power transmission efficiency can be reduced compared to the state of being aligned with the wireless power transmitter. In this case, the control error value of the control error packet is varied, and the output power of the wireless power transmitter 2201 increases rapidly.

That is, as shown in FIG. 23, the wireless power transmitter 2201 performs stable power transmission in the aligned state (first state) with the wireless power receiver 2202. At this time, the wireless power transmitter 2201 receives the control error value CEV within the critical range from the wireless power receiver 2202.

If the alignment of the wireless power transmitter 2201 and the wireless power receiver 2202 is changed (second state) when the electronic device moves as in the example of FIG. 22A in the first state, the wireless power transmitter 2201 transmits the transmission power . At this time, the control error value (CEV) is + or? A first swing 2301 which is variable to the first swing 2301 may be sensed. The control error value according to the first swing 2301 may be a value that is increased and decreased than the control error value received from the wireless power receiver 2202 in the first state.

The control error value receives a control error value having a value larger than the control error value sensed in the first swing 2301 according to the power surge in the second state. (Second Swing 2302) The control error value detected in the first swing 2301 is greater than the control error value sensed in the first swing 2301. [ Also, the control error value is rapidly increased.

In this state, the output power of the wireless power transmitter 2201 is reduced when the electronic device is in an alignment state (third state) with the wireless power transmitter 2201 in a short period of time (b). At this time, the output power of the wireless power transmitter 2201 is not reduced even when the wireless power transmitter 2201 is in alignment with the wireless power receiver 2202. Thus, the wireless power receiver 2202 experiences internal damage due to high output power. On the other hand, the control error value may be detected in the first swing when the wireless power transmitter 2201 and the wireless power receiver 2202 are changed to the aligned state as shown in FIG. That is, the wireless power transmitter 2201 can receive a control error value that is finely variable from the wireless power receiver 2202 before the output power is reduced by changing to the alignment state.

As described above, when the alignment state of the wireless power transmitter 2201 and the wireless power receiver 2202 is aligned, The amount of power transmitted from the wireless power transmitter 2201 to the wireless power receiver 2202 may cause damage to the wireless power receiver 2202 and the electronic equipment containing it. Thus, the wireless power transmitter can control the transmit power based on the control error value received at the wireless power receiver. 24 and 25, the transmission power control operation according to the alignment state variable of the wireless power transmitter and the wireless power receiver will be described in detail.

FIG. 24 is a view for explaining an operation state of a wireless power transmitter according to another embodiment, and FIG. 25 is a view for explaining a power control method in a wireless power transmitter according to another embodiment.

Referring to FIGS. 24 and 25, the wireless power transmitter can check the status information received from the wireless power receiver in the power transmission operation state (S2501). Specifically, the wireless power transmitter transmits the control error packet received from the wireless power receiver You can check the included control error value.

At this time, the wireless power transmitter can perform stable power transmission in the first state (alignment state) as shown in FIG. 23, and can receive the control error value within the threshold from the wireless power receiver. The control error value received in the first state may be within a range of -1, 0, +1.

The wireless power transmitter can determine whether the control error value has a positive (+) value or a negative (-) value that exceeds the threshold value when the receiver status information is checked. Specifically, it can be determined whether the control error value received from the wireless power receiver is a positive (+) value greater than or equal to the threshold value (S2502). The threshold value may be 0 or +1. That is, it can be determined whether the control error value exceeds +1. For example, the threshold may be a positive first threshold.

Meanwhile, the wireless power transmitter can determine whether the identified control error value has a negative (-) value below the threshold if the identified control error value has a positive value that is greater than or equal to the threshold value (S2503) The threshold may be 0 or? 1. That is, a control error value of less than -1. For example, the threshold may be a negative first threshold.

The absolute value of the positive first threshold value and negative negative first threshold value may be the same.

When the control error value equal to or more than the positive threshold value is continuously received, as shown in FIG. 22, the first swing 2401 that the alignment state of the wireless power transmitter and the wireless power receiver changes is detected .

That is, when the absolute value of the control error value of the control error packet continuously receives a positive value and a negative value larger than the first threshold, the first switch 2401 detects the phenomenon of the first switch 2401, Weights can be reflected in the power.

Therefore, damage of the wireless power receiver (or electronic device) due to the second swing 2402 that may occur after the first swing 2401 is prevented can be prevented.

However, it can not be absolutely defined that the alignment state of the wireless power transmitter and the wireless power receiver has changed in accordance with the first swing. This is because a fine swing phenomenon may occur depending on various charging environments. Therefore, it is possible to perform more efficient control by additionally controlling the transmission power only when the second swing 2402 of the control error value occurs. Depending on the situation, step S2504 described below may be omitted or added. Specifically, the wireless power transmitter determines whether the control error value is greater than or equal to a threshold absolute control error value when a control error value that is out of the threshold range is detected. (S2504) It may be the maximum control error value that can be received from the receiver. The wireless power transmitter determines whether the control error value has a positive value if an absolute control error value exceeding a threshold value is determined according to a determination result (S2504).

In the wireless power transmitter according to the embodiment, the range of the first threshold for detecting the first swing 2401 of the control error value is larger than the variation range of the control error value that is in the first state (alignment state). In addition, the range of the second threshold for detecting the second swing 2402 of the control error value is larger than the range of the threshold for sensing the first swing 2401. Thus, the absolute control error value may have a value outside the range of the first threshold.

That is, if the absolute value of the control error value of the control error packet has an absolute control error value larger than the second threshold value, the transmission power can be weighted.

The wireless power transmitter may generate the second power value by reflecting the first weight if the control error value has a positive value. (S2506) The first weight value may have a value less than 1. Specifically, the first weight may have a value of 1 or less than 1. For example, the first weight may have a value of 0.5. Therefore, it is possible to prevent the electronic equipment from being damaged by restricting the rapid increase of the transmission power.

The second power value reflecting the first weight in the transmission power curve shown in FIG. 24 is increased (2403) to a low speed, . At this time, the wireless power transmitter and the wireless power receiver are in a state of being changed from the alignment state to the spaced state.

Meanwhile, the wireless power transmitter may generate the second power value by reflecting the second weight value when the control error value does not have a positive value. (S2508) The second weight value may have a value of more than one. Specifically, the second weight may have a value between 1 and 2 or less. For example, the second weight may have a value of two. Therefore, when the transmission power rises sharply, it is possible to reduce the transmission power again so as to prevent damage to the electronic equipment.

The wireless power transmitter can transmit the power with the second power value reflecting the second weight (S2509_). In other words, in the transmission power curve shown in FIG. 24, the second power value reflecting the second weight is rapidly reduced 2402 At this time, the wireless power transmitter and the wireless power receiver are in a state in which they are shifted from the spaced state to the aligned state.

In this embodiment, when the wireless power transmitter and the wireless power receiver are respectively changed to the aligned state or the separated state, the wireless power transmitter can control the transmission power by referring to the control error value received from the wireless power receiver. That is, depending on the alignment state, the control error value reflects the weight of the transmission power according to whether the second swing occurs and the control error value after the first swing is increased or decreased to decrease the transmission power to a low speed, The damage of the wireless power receiver can be minimized.

The wireless power transmitter or wireless power transmission method according to embodiments can have an excellent effect, especially in protecting the wireless power receiver, especially in the case of power transmission for high-speed charging as well as low power transmission or for medium power / high power transmission.

It will be apparent to those skilled in the art that the embodiments may be embodied in other specific forms without departing from the spirit and essential characteristics of the embodiments.

Accordingly, the above description should not be construed in a limiting sense in all respects and should be considered illustrative. The scope of the present embodiment should be determined by rational interpretation of the appended claims, and all changes within the equivalent scope of the present embodiment are included in the scope of the present embodiment.

Claims (9)

A power transmitting unit including a transmitting coil;
A power conversion unit for converting an intensity of power applied from the outside;
And a controller for controlling transmission power to the wireless power receiver,
The control unit
If the control error value of the control error packet is received consecutively below the positive first threshold value or below the negative first threshold value, it is determined whether the received control error value is the absolute control error value equal to or greater than the second threshold value And if the determined control error value has an absolute control error value equal to or greater than the second threshold value,
Wherein the power transmitting unit transmits power to the wireless power receiver with the weighted reflected power,
Wherein the absolute control error value above the second threshold is a positive or negative maximum control error value that can be received from the wireless power receiver. delete delete The method according to claim 1,
The control unit
If the absolute control error value is positive, generating a second power value by reflecting the first weight value,
And if the absolute control error value is negative, reflects a second weight to generate a second power value. 5. The method of claim 4,
The first weight having a value less than 1,
Wherein the second weight has a value greater than one. A wireless power transmission method for wirelessly transmitting power to a wireless power receiver,
Receiving a control error packet received from the wireless power receiver in a power transmission step;
Determining whether a control error value of the control error packet is successively received below a positive first threshold value or below a first negative threshold value;
Determining whether the received control error value is an absolute control error value equal to or greater than a second threshold value;
Generating a second power value by reflecting a weight on the transmission power if the determined control error value has an absolute control error value equal to or greater than the second threshold value;
And performing power transmission with the second power value,
Wherein the absolute control error value above the second threshold value is a positive or a negative maximum control error value that can be received from the wireless power receiver. delete The method according to claim 6,
If the absolute control error value is positive, generating a second power value by reflecting the first weight value,
And generating a second power value by reflecting the second weight if the absolute control error value is negative; 9. The method of claim 8,
Wherein the first weight has a value less than one and the second weight has a value greater than one.

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