Device and method of communicating in wireless power transmission system

Abstract

To provide a wireless power transmission system.SOLUTION: The present invention relates to a device and a method of communicating in the wireless power transmission system. A wireless power transmission apparatus includes: a communication-control unit configured so as to perform the negotiation with a wireless power receiver about a first available power index; and a power conversion part configured so as to transmit wireless power to the wireless power receiver in such a manner that a magnetic coupling is generated in a primary coil according to the first available power index. The wireless power transmission apparatus has the effect that the wireless power transmission apparatus can dynamically and appropriately adjust an available power index upon desiring according to a surrounding environment-situation to perform the leading start of communication and certification.SELECTED DRAWING: Figure 16

Description

[Technical Field]

[0001] The present invention relates to wireless power transmission, and more particularly to an apparatus and method for communicating in a wireless power transmission system. [Background technology]

[0002] Wireless power transmission technology is a technology that wirelessly transmits power between a power source and an electronic device. For example, wireless power transmission technology allows wireless devices such as smartphones and tablets to be charged simply by placing them on a wireless charging pad, thereby providing greater mobility, convenience, and safety than existing wired charging environments that use wired charging connectors. In addition to wireless charging of wireless devices, wireless power transmission technology is gaining attention as an alternative to existing wired power transmission environments in a variety of fields, including electric vehicles, various wearable devices such as Bluetooth earphones and 3D glasses, home appliances, furniture, underground facilities, buildings, medical devices, robots, and leisure activities.

[0003] The wireless power transmission method is also called a contactless power transmission method, a no-point-of-contact power transmission method, or a wireless charging method. A wireless power transmission system includes a wireless power transmitter that supplies electric energy by wireless power transmission, and a wireless power receiver that receives the electric energy wirelessly from the wireless power transmitter and supplies power to a power receiver such as a battery cell.

[0004] There are various wireless power transmission technologies, including those that transmit power through magnetic coupling, radio frequency (RF), microwave, and ultrasonic waves. Magnetic coupling-based methods are further classified into magnetic induction and magnetic resonance. Magnetic induction transmits energy by using a current induced in the receiving coil by a magnetic field generated from a battery cell in the transmitting coil through electromagnetic coupling between the transmitting and receiving coils. Magnetic resonance is similar to magnetic induction in that it uses a magnetic field. However, magnetic resonance differs from magnetic induction in that it transmits energy by generating a magnetic field at both ends of the transmitting and receiving coils when a specific resonant frequency is applied to the transmitting and receiving coils, causing resonance.

[0005] In a communication protocol between a wireless power transmitting device and a receiving device, if the receiving device is the sender or master that initiates or leads communication, the wireless power transmitting device can only send a response to a request from the wireless power receiving device. In this case, even if the wireless power transmitting device detects a foreign object in the charging area (or magnetic field area) or the charging environment changes, it cannot control the power level at a desired timing and cannot perform authentication. [Prior art documents] [Patent Documents] [Patent Document 1] U.S. Patent Application Publication No. 2013 / 0119778 [Patent Document 2] U.S. Patent Application Publication No. 2012 / 0212071

[0006] Therefore, there is a need for an apparatus and method that enables a wireless power transmission apparatus to acquire status and authority as a master / transmitter depending on the situation, and that performs efficient and stable power management and authentication by reflecting the current surrounding situation / environment in real time. Summary of the Invention [Problem to be solved by the invention]

[0007] A technical object of the present invention is to provide an apparatus and method for communicating in a wireless power transmission system.

[0008] Another technical object of the present invention is to provide a wireless power transmission apparatus and method for performing communication in a wireless power transmission system.

[0009] It is still another technical object of the present invention to provide a wireless power receiving apparatus and method for performing communication in a wireless power transmission system. [Means for solving the problem]

[0010] According to one aspect of the present invention, there is provided a wireless power transmitting device, the device including: a communication / control unit configured to negotiate with a wireless power receiving device regarding a first available power indicator; and a power conversion unit configured to generate magnetic coupling in a primary coil to transmit wireless power to the wireless power receiving device according to the first available power indicator, wherein the communication / control unit is capable of receiving a received power packet from the wireless power receiving device indicating power received by the wireless power receiving device, transmitting a bit pattern response to the wireless power receiving device requesting communication by the wireless power transmitting device, receiving a response signal from the wireless power receiving device indicating readiness to receive communication by the wireless power transmitting device, and transmitting a packet regarding a second available power indicator to the wireless power receiving device.

[0011] In one aspect, the first available power indicator and the second available power indicator may be guaranteed power.

[0012] In another aspect, the first available power indicator and the second available power indicator may be target powers.

[0013] In yet another aspect, the packet relating to the second available power indicator can include a capability packet of the wireless power transmission device.

[0014] In yet another aspect, the bit pattern response may indicate that the wireless power transmitting apparatus requests the wireless power receiving apparatus to obtain authorization to transmit a predetermined packet.

[0015] In yet another aspect, the bit pattern response is defined as a different pattern than the bit patterns for an ACK response, a NAK response, and an ND response indicating that the request is not valid.

[0016] According to another aspect of the present invention, there is provided a wireless power transmission method, the method including: negotiating with a wireless power receiving device regarding a first available power indicator, transmitting wireless power to the wireless power receiving device by generating magnetic coupling to a primary coil according to the first available power indicator, receiving a received power packet from the wireless power receiving device indicating power received by the wireless power receiving device, transmitting a bit pattern response to the wireless power receiving device requesting communication by the wireless power transmitting device, receiving a response signal from the wireless power receiving device indicating readiness to receive communication by the wireless power transmitting device, and transmitting a packet regarding a second available power indicator to the wireless power receiving device.

[0017] According to yet another aspect of the present invention, there is provided a wireless power receiving device, the device including: a communication / control unit configured to negotiate with a wireless power transmitting device regarding a first available power indicator; and a power pickup unit configured to receive wireless power from the wireless power transmitting device by magnetic coupling generated in a primary coil by the first available power indicator, wherein the communication / control unit is capable of transmitting a received power packet regarding the received wireless power to the wireless power transmitting device, receiving a bit pattern response from the wireless power transmitting device requesting communication by the wireless power transmitting device, transmitting a response signal to the wireless power transmitting device indicating readiness to receive communication by the wireless power transmitting device, and receiving a packet regarding a second available power indicator from the wireless power transmitting device.

[0018] According to yet another aspect of the present invention, there is provided a wireless power receiving method, the method including: negotiating with a wireless power transmission device regarding a first available power indicator, receiving wireless power from the wireless power transmission device by magnetic coupling generated in a primary coil by the first available power indicator, transmitting a received power packet indicating the received wireless power to the wireless power transmission device, receiving from the wireless power transmission device a bit pattern response requesting communication by the wireless power transmission device, transmitting to the wireless power transmission device a response signal indicating readiness to receive communication by the wireless power transmission device, and receiving from the wireless power transmission device a packet regarding a second available power indicator. [Effects of the Invention]

[0019] According to the present invention, a wireless power transmitting apparatus can dynamically and appropriately adjust the available power index at a desired time according to the surrounding environment / situation, and can proactively start communication and authentication. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a block diagram of a wireless power system 10 according to one embodiment. [Figure 2] FIG. 1 is a block diagram of a wireless power system 10 according to another embodiment. [Figure 3] 1 illustrates various embodiments of electronic devices into which a wireless power transmission system may be incorporated. [Figure 4] FIG. 10 is a block diagram of a wireless power transmission system according to another embodiment. [Figure 5] FIG. 10 is a state transition diagram for explaining a wireless power transmission procedure. [Figure 6] 1 illustrates a power control method according to one embodiment. [Figure 7] FIG. 10 is a block diagram of a wireless power transmission device according to another embodiment. [Figure 8] 1 shows a wireless power receiving device according to another embodiment. [Figure 9] 1 illustrates a communication frame structure according to one embodiment. [Figure 10] 1 is a diagram illustrating the structure of a sync pattern according to one embodiment. [Figure 11] 1 illustrates an operation state of a wireless power transmitter and a wireless power receiver in a shared mode according to an embodiment. [Figure 12] 1 illustrates available power metrics according to an example. [Figure 13] We now describe how each available power indicator is set during the negotiation phase according to one example. [Figure 14] Another example will now be described of how each available power indicator is set during the negotiation phase. [Figure 15] 10 is a diagram illustrating a process of performing power control based on each available power indicator in a power transmission phase according to an example. [Figure 16] FIG. 10 is an exemplary diagram illustrating a process of power control based on each available power indicator in a power transmission phase according to another example. [Figure 17] 1 is a protocol for a procedure for transmitting an RFR according to one embodiment. [Figure 18]1 is an RFA packet structure according to one embodiment. [Figure 19] 10 is a diagram illustrating the structure of a wireless power transmitter's capability packet including an available power indicator according to one embodiment. [Figure 20] 1 illustrates a structure of a target power packet of a wireless power transmitting device according to an embodiment. [Figure 21] 10 illustrates a structure of a response packet of a wireless power receiving device according to an embodiment. [Figure 22] 10 illustrates a structure of a response packet of a wireless power transmitting device according to an embodiment. [Figure 23] 10 is a flowchart illustrating a wireless power transmitting device transmitting information about an available power indicator based on an additional transmission protocol according to an embodiment. [Figure 24a] 1 is a diagram illustrating in detail the ATX (or ATD) step of performing additional transmission according to one embodiment. [Figure 24b] FIG. 10 is a detailed diagram illustrating the ATX (or ATD) step of performing additional transmission according to another embodiment. [Figure 25] 10 is a flowchart illustrating a wireless power transmitting device transmitting information about an available power index based on an additional transmission protocol according to another embodiment. [Figure 26] This is an example of a GR packet. [Figure 27] 1 is an example of an RA packet. [Figure 28] This is an example of an ACK packet. [Figure 29] This is an example of an SOD / EOD packet. [Figure 30] FIG. 1 illustrates an ADT data transmission procedure according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, the term "wireless power" refers to any form of energy associated with an electric field, magnetic field, electromagnetic field, etc., that is transmitted from a wireless power transmitter to a wireless power receiver without using a physical electromagnetic conductor. Wireless power may also be referred to as a wireless power signal, or may refer to an oscillating magnetic flux enclosed by a primary coil and a secondary coil. For example, power conversion in a system for wirelessly charging devices including mobile phones, cordless phones, iPods, MP3 players, headsets, etc. is described herein. Generally, the basic principles of wireless power transmission include, for example, a method of transmitting power by magnetic coupling, a method of transmitting power by radio frequency (RF), a method of transmitting power by microwave, and a method of transmitting power by ultrasound.

[0022] FIG. 1 is a block diagram of a wireless power system 10 according to one embodiment.

[0023] As shown in FIG. 1, a wireless power system 10 includes a wireless power transmitter 100 and a wireless power receiver 200.

[0024] The wireless power transmitting apparatus 100 generates a magnetic field when power is applied from an external power source S. The wireless power receiving apparatus 200 generates a current using the generated magnetic field and receives power wirelessly.

[0025] In addition, the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200 in the wireless power system 10 can transmit and receive various information required for wireless power transmission. Here, communication between the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200 is performed by either in-band communication using a magnetic field used for wireless power transmission or out-band communication using a separate communication carrier.

[0026] Here, the wireless power transmission apparatus 100 may be provided in a fixed or mobile type. Examples of the fixed type include an embedded type in a ceiling, wall, or furniture such as a table indoors, an implant type installed in a parking lot, a bus stop, or a subway station outdoors, or an installed type in a transportation means such as a vehicle or train. The mobile type wireless power transmission apparatus 100 may be implemented as a part of a mobile device having a portable weight and size, or as a part of another device such as a laptop computer cover.

[0027] Furthermore, the wireless power receiving apparatus 200 should be interpreted as a comprehensive concept including various electronic devices equipped with a battery and various home appliances that are powered by wireless power instead of a power cable. Representative examples of the wireless power receiving apparatus 200 include a portable terminal, a cellular phone, a smart phone, a personal digital assistant (PDA), a portable media player (PMP), a Wibro terminal, a tablet, a laptop, a digital camera, a navigation terminal, a television, an electric vehicle (EV), etc.

[0028] The wireless power system 100 may include one or more wireless power receiving devices 200. In Fig. 1, the wireless power transmitting device 100 and the wireless power receiving device 200 are shown exchanging power one-to-one, but as shown in Fig. 2, one wireless power transmitting device 100 may transmit power to multiple wireless power receiving devices 200-1, 200-2, ..., 200-M. In particular, when wireless power transmission is performed using the magnetic resonance method, one wireless power transmitting device 100 may transmit power to multiple wireless power receiving devices 200-1, 200-2, ..., 200-M simultaneously by applying a simultaneous transmission method or a time division transmission method.

[0029] 1 illustrates the wireless power transmitting apparatus 100 directly transmitting power to the wireless power receiving apparatus 200, a separate wireless power transceiver such as a relay or repeater for increasing the wireless power transmission distance may be provided between the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200. In this case, power may be transmitted from the wireless power transmitting apparatus 100 to the wireless power transceiver, and the wireless power transceiver may transmit power again to the wireless power receiving apparatus 200.

[0030] Hereinafter, the terms "wireless power receiver," "power receiver," and "receiver" referred to in this specification refer to the wireless power receiving device 200. Also, the terms "wireless power transmitter," "power transmitter," and "transmitter" referred to in this specification refer to the wireless power receiving and transmitting device 100.

[0031] FIG. 3 illustrates various embodiments of electronic devices in which the wireless power transmission system may be implemented.

[0032] Figure 3 shows electronic devices classified according to the amount of power transmitted and received by a wireless power transmission system. As shown in Figure 3, a low-power (approximately 5W or less or approximately 20W or less) wireless charging method can be applied to wearable devices such as smart watches, smart glasses, head-mounted displays (HMDs), and smart rings, as well as mobile (or portable) electronic devices such as earphones, remote controls, smartphones, PDAs, and tablet computers.

[0033] A medium-power (approximately 50W or less or approximately 200W or less) wireless charging method can be applied to small and medium-sized home appliances such as laptops, robot vacuum cleaners, TVs, audio equipment, vacuum cleaners, and monitors. A high-power (approximately 2kW or less or approximately 22kW or less) wireless charging method can be applied to kitchen appliances such as blenders, microwave ovens, and electric rice cookers, and personal transportation devices (or electronic devices / transportation means) such as wheelchairs, electric kick scooters, electric bicycles, and electric cars.

[0034] The electronic devices / mobile means described above (or shown in FIG. 1) may each include a wireless power receiver, which will be described later. Therefore, the electronic devices / mobile means described above can be charged by receiving power wirelessly from a wireless power transmitter.

[0035] Although the following description will be focused on a mobile device to which a wireless power charging method is applied, this is merely an embodiment, and the wireless charging method according to the present invention can be applied to the various electronic devices described above.

[0036] The wireless power transmitting and receiving device can provide a very convenient user experience and interface (UX / UI). That is, a smart wireless charging service can be provided, and the smart wireless charging service can be realized based on the UX / UI of a smartphone that includes the wireless power transmitting device. For such applications, the interface between the smartphone's processor and the wireless charging receiving device allows "drop and play" bidirectional communication between the wireless power transmitting device and the receiving device.

[0037] For example, a user may experience a smart wireless charging service at a hotel. When the user enters a hotel room and places their smartphone on a wireless charger in the room, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. During this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone detects that it is located on the wireless charger, detects the reception of wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state in which it asks the user to opt in to additional features. To this end, the smartphone may display a message on the screen with or without an audible alarm. An example of the message may include a phrase such as, "Welcome to ### hotel. Select "Yes" to activate smart charging functions: Yes | No Thanks." If the user selects Yes or No Thanks, the smartphone performs the next step selected by the user. If Yes is selected, the smartphone transmits the corresponding information to the wireless charger. Then, the smartphone and the wireless charger perform the smart charging function together.

[0038] The smart wireless charging service can also include receiving auto-filled WiFi credentials, for example, the wireless charger sending WiFi credentials to the smartphone, and the smartphone running an appropriate app to automatically fill in the WiFi credentials received from the wireless charger.

[0039] The smart wireless charging service may also include running a hotel application that offers hotel promotions or obtaining remote check-in / check-out and contact information.

[0040] As another example, a user can experience a smart wireless charging service in a vehicle. When a user gets into a vehicle and places a smartphone on a wireless charger, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. During this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone detects that it is placed on the wireless charger, detects the reception of wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state in which it queries the user for identity verification.

[0041] In this state, the smartphone automatically connects to the car via Wi-Fi and / or Bluetooth. The smartphone can display a message on the screen with or without an audible alarm. An example of the message may include a phrase such as, "Welcome to your car. Select 'Yes' to synchronize device with in-car controls: Yes | No Thanks." If the user selects Yes or No Thanks and inputs it, the smartphone performs the next step selected by the user. If Yes is selected, the smartphone transmits the corresponding information to the wireless charger. The smartphone and the wireless charger can then operate the in-vehicle application / display software to perform in-vehicle smart control functions together. The user can enjoy desired music and confirm the correct map location. The in-vehicle application / display software may include the ability to provide synchronized access for passersby.

[0042] As another example, a user can experience smart wireless charging at home. When a user enters a room and places a smartphone on a wireless charger, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. During this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone detects that it is placed on a wireless charger, detects the reception of wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state in which it asks the user for consent (opt-in) to additional features. To this end, the smartphone can display a message on the screen with or without an audible alarm. An example of the message may include a phrase such as, "Hi xxx, Would you like to activate night mode and secure the building? : Yes | No Thanks." If the user selects Yes or No Thanks, the smartphone performs the next step selected by the user. If Yes is selected, the smartphone transmits the corresponding information to the wireless charger. The smartphone and the wireless charger can at least recognize the user's patterns and recommend the user to close doors and windows, turn off the fire, or set an alarm.

[0043] Standards for wireless power transmission include the wireless power consortium (WPC), the air fuel alliance (AFA), and the power matters alliance (PMA).

[0044] The WPC standard defines a baseline power profile (BPP) and an extended power profile (EPP), where BPP is for wireless power transmitters and receivers that support 5W power transmission, and EPP is for wireless power transmitters and receivers that support power transmission in the range greater than 5W but less than 30W.

[0045] Each standard covers a variety of wireless power transmitters and receivers that use different power levels and are classified into different power classes (PCs) or categories.

[0046] For example, the WPC classifies wireless power transmitters and receivers into power classes (PC-1, PC0, PC1, and PC2) and provides standard documents for each PC. The PC-1 standard relates to wireless power transmitters and receivers that provide guaranteed power of less than 5W. PC-1 applications include wearable devices such as smart watches.

[0047] The PC0 standard relates to wireless power transmitters and receivers that provide a guaranteed power of 5W. The PC0 standard includes EPP, which provides a guaranteed power of up to 30W. In-band (IB) communication is the mandatory communication protocol for PC0, but out-of-band (OBB) communication, used as an optional backup channel, can also be used. A wireless power receiver can identify whether it supports OOB by setting an OOB flag in a configuration packet. A wireless power transmitter that supports OOB can enter the OOB handover phase by transmitting a bit pattern for OOB handover in response to the configuration packet. The response to the configuration packet can be NAK, ND, or a newly defined 8-bit pattern. PC0 applications include smartphones.

[0048] The PC1 standard relates to wireless power transmitters and receivers that provide guaranteed power of 30W to 150W. OOB is the required communication channel for PC1, and IB is used for initialization and link establishment to OOB. A wireless power transmitter can enter the OOB handover phase by transmitting a bit pattern for OOB handover in response to a configuration packet. PC1 applications include laptops and power tools.

[0049] The PC2 standard relates to wireless power transmitters and receivers that provide guaranteed power between 200W and 2kW, and its applications include kitchen appliances.

[0050] As described above, PCs are distinguished by power levels, and whether compatibility between identical PCs is supported is optional or mandatory. Here, compatibility between identical PCs means that power can be transmitted and received between identical PCs. For example, if a wireless power transmitting apparatus, which is PCx, can charge a wireless power receiving apparatus having the same PCx, compatibility between identical PCs can be considered to be maintained. Similarly, compatibility between different PCs can also be supported. Here, compatibility between different PCs means that power can be transmitted and received between different PCs. For example, if a wireless power transmitting apparatus, which is PCx, can charge a wireless power receiving apparatus having PCy, compatibility between different PCs can be considered to be maintained.

[0051] Supporting compatibility between PCs is a very important issue in terms of user experience and infrastructure construction. However, maintaining compatibility between PCs presents various technical challenges, such as the following:

[0052] In the case of compatibility between the same PCs, for example, a laptop-charging type wireless power receiving device that can charge stably only when power is transmitted continuously may have problems receiving stable power from a power tool-type wireless power transmitting device that transmits power discontinuously, even if the wireless power transmitting device is the same PC. Also, in the case of compatibility between different PCs, for example, if a wireless power transmitting device with a guaranteed power of at least 200 W transmits power to a wireless power receiving device with a maximum guaranteed power of 5 W, the wireless power receiving device may be damaged by overvoltage. As a result, it is difficult to use PCs as an indicator / standard representing / indicating compatibility.

[0053] Hereinafter, a "profile" is newly defined as an index / criteria representing / indicating compatibility. That is, it can be interpreted that compatibility is maintained between wireless power transceiver devices having the same "profile" and stable power transmission / reception is possible, while power transmission / reception is impossible between wireless power transceiver devices having different "profiles." A profile can be defined based on compatibility and / or application, regardless of (or independently of) the power class.

[0054] For example, the profiles are broadly divided into four categories: i) mobile, ii) power tools, iii) kitchen, and iv) wearable.

[0055] In the case of the "Mobile" profile, the PC can be defined as PC0 and / or PC1, the communication protocol / method as IB and OOB, and the operating frequency as 87 to 205 kHz. Examples of applications include smartphones and laptops.

[0056] In the case of the "power tool" profile, the PC can be defined as PC1, the communication protocol / method as IB, and the operating frequency as 87 to 145 kHz, and an example of an application is a power tool.

[0057] In the case of the "Kitchen" profile, the PC can be defined as PC2, the communication protocol / method as NFC-based, and the operating frequency as less than 100 kHz. Examples of applications include kitchen / home appliances.

[0058] In the case of the "Wearable" profile, the PC can be defined as PC-1, the communication protocol / method as IB, and the operating frequency as 87 to 205 kHz. An example of an application is a wearable device worn on the user's body.

[0059] Maintaining compatibility among the same profiles is mandatory, while maintaining compatibility among other profiles may be optional.

[0060] The above-mentioned profiles (mobile profile, power tool profile, kitchen profile, and wearable profile) can be generalized and expressed as profiles 1 to n, and new profiles can be added / substituted depending on the WPC standard and embodiment.

[0061] When profiles are defined in this way, a wireless power transmitting apparatus can selectively transmit power only to wireless power receiving apparatuses that have the same profile as itself, enabling more stable power transmission. In addition, the burden on the wireless power transmitting apparatus is reduced, and the wireless power receiving apparatus will no longer attempt to transmit power to an incompatible wireless power receiving apparatus, thereby reducing the risk of damage to the wireless power receiving apparatus.

[0062] PC1 in the "Mobile" profile can be defined by borrowing a selective extension such as OOB based on PC0, and in the case of the "Power Tool" profile, PC1 "Mobile" profile can be defined as a simply modified version. Also, while the goal has been to maintain compatibility between the same profiles up until now, technology may be developed in the direction of maintaining compatibility between different profiles in the future. A wireless power transmitter or a wireless power receiver can notify its profile to the other device in various ways.

[0063] The AFA standard refers to a wireless power transmitting device as a PTU (power transmitting unit) and a wireless power receiving device as a PRU (power receiving unit). PTUs are classified into multiple classes as shown in Table 1, and PRUs are classified into multiple categories as shown in Table 2.

[0064] [Table 1]

[0065] [Table 2]

[0066] As shown in Table 1, the maximum output power capability of a Class n PTU is TX_IN_MAX A PRU cannot draw more power than specified for its category.

[0067] FIG. 4 is a block diagram of a wireless power transmission system according to another embodiment.

[0068] As shown in FIG. 4, the wireless power transmission system 10 includes a mobile device 450 that wirelessly receives power and a base station 400 that wirelessly transmits power.

[0069] The base station 400 is a device that provides inductive power or resonant power and can include at least one wireless power transmitter 100 and a system unit 405. The wireless power transmitter 100 can transmit and control the transmission of inductive power or resonant power. The wireless power transmitter 100 can include a power conversion unit 110 that converts electrical energy into a power signal by generating a magnetic field using primary coil(s), and a communications & control unit 120 that controls communication with the wireless power receiver 200 and power transfer to transfer power at an appropriate level. The system unit 405 can control other operations of the base station 100, such as input power provisioning, control of multiple wireless power transmitters, and user interface control.

[0070] The primary coil can generate an electromagnetic field using AC power (or voltage or current). When AC power (or voltage or current) of a specific frequency output from the power conversion unit 110 is applied to the primary coil, the primary coil can generate a magnetic field of a specific frequency. The magnetic field can be generated in a non-radiative or radiative manner, and the wireless power receiving device 200 receives it and generates a current. In other words, the primary coil transmits power wirelessly.

[0071] In the magnetic induction method, the primary coil and secondary coil may have any suitable form, for example, a copper wire wound around a highly permeable material such as ferrite or amorphous metal. The primary coil may also be called a primary core, primary winding, primary loop antenna, etc. Meanwhile, the secondary coil may also be called a secondary core, secondary winding, secondary loop antenna, pickup antenna, etc.

[0072] When using the magnetic resonance method, the primary coil and the secondary coil are provided in the form of a primary resonant antenna and a secondary resonant antenna, respectively. The resonant antenna may have a resonant structure including a coil and a capacitor. In this case, the resonant frequency of the resonant antenna is determined by the inductance of the coil and the capacitance of the capacitor. Here, the coil may be formed in the form of a loop. Also, a core may be disposed inside the loop. The core may include a physical core such as a ferrite core or an air core.

[0073] Energy transmission between the primary and secondary resonant antennas can occur through magnetic field resonance. Resonance refers to a phenomenon in which, when a near field corresponding to a resonant frequency is generated in one resonant antenna and another resonant antenna is located nearby, the two resonant antennas are coupled together, resulting in highly efficient energy transfer between the resonant antennas. When a magnetic field corresponding to the resonant frequency is generated between the primary and secondary resonant antennas, the primary and secondary resonant antennas resonate with each other. This allows the magnetic field generated by the primary resonant antenna to be focused toward the secondary resonant antenna with higher efficiency than when the magnetic field is generally emitted into free space. Therefore, energy can be transferred from the primary resonant antenna to the secondary resonant antenna with high efficiency. The magnetic induction method is similar to the magnetic resonance method, but in this case, the frequency of the magnetic field does not need to be the resonant frequency. Instead, the magnetic induction method requires matching between the loops constituting the primary and secondary coils, and the distance between the loops must be very close.

[0074] Although not shown, the wireless power transmission apparatus 1100 may further include a communication antenna. The communication antenna can transmit and receive communication signals using a communication carrier other than magnetic field communication. For example, the communication antenna can transmit and receive communication signals of Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, NFC, etc.

[0075] The communication / control unit 120 can transmit and receive information to and from the wireless power receiving device 200. The communication / control unit 120 can include at least one of an IB communication module or an OOB communication module.

[0076] The IB communication module can transmit and receive information using magnetic waves centered on a specific frequency. For example, the communication / control unit 120 can perform in-band communication by transmitting information on magnetic waves via a primary coil or by receiving magnetic waves containing information via a primary coil. In this case, the communication / control unit 120 can embed information in magnetic waves or analyze magnetic waves containing information using modulation methods such as binary phase shift keying (BPSK) or amplitude shift keying (ASK) and encoding methods such as Manchester coding or non-return-to-zero level (NZR-L) coding. Using this IB communication, the communication / control unit 120 can transmit and receive information over distances of up to several meters at a data transmission rate of several kbps.

[0077] The OOB communication module may also perform out-of-band communication via a communication antenna. For example, the communication / control unit 120 may be provided as a short-range communication module. Examples of short-range communication modules include Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC communication modules.

[0078] The communication / control unit 120 can control the overall operation of the wireless power transmission apparatus 100. The communication / control unit 120 can perform calculations and processes of various information and control each component of the wireless power transmission apparatus 100.

[0079] The communication / control unit 120 can be implemented in a computer or similar device using hardware, software, or a combination thereof. In terms of hardware, the communication / control unit 120 can be implemented in the form of an electronic circuit that processes electrical signals and performs control functions, and in terms of software, the communication / control unit 120 can be implemented in the form of a program that drives the hardware communication / control unit 120.

[0080] The communication / control unit 120 can control the transmission power by controlling an operating point. The controlled operating point may correspond to a combination of a frequency (or phase), a duty cycle, a duty ratio, and a voltage amplitude. The communication / control unit 120 can control the transmission power by adjusting at least one of the frequency (or phase), the duty cycle, the duty ratio, and the voltage amplitude. Alternatively, the wireless power transmitter 100 can supply a constant power, and the wireless power receiver 200 can control the reception power by controlling the resonant frequency.

[0081] The mobile device 450 includes a wireless power receiver 200 that receives wireless power through a secondary coil, and a load 455 that receives and stores the power received by the wireless power receiver 200 and supplies it to the device.

[0082] The wireless power receiving device 200 may include a power pick-up unit 210 and a communications & control unit 220. The power pick-up unit 210 receives wireless power via a secondary coil and converts it into electrical energy. The power pick-up unit 210 rectifies the AC signal obtained via the secondary coil and converts it into a DC signal. The communications & control unit 220 controls the transmission and reception of wireless power (power transmission and reception).

[0083] The secondary coil can receive wireless power transmitted from the wireless power transmitting apparatus 100. The secondary coil can receive power using a magnetic field generated in the primary coil. Here, if a specific frequency is a resonant frequency, a magnetic resonance phenomenon occurs between the primary coil and the secondary coil, allowing for more efficient power reception.

[0084] Although not shown in FIG. 4, the communication / control unit 220 may further include a communication antenna. The communication antenna may transmit and receive communication signals using a communication carrier other than magnetic field communication. For example, the communication antenna may transmit and receive communication signals using Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, NFC, etc.

[0085] The communication / control unit 220 transmits and receives information to and from the wireless power transmitting apparatus 100. The communication / control unit 220 may include at least one of an IB communication module or an OOB communication module.

[0086] The IB communication module can transmit and receive information using magnetic waves centered on a specific frequency. For example, the communication / control unit 220 can perform IB communication by transmitting information on magnetic waves via a secondary coil or by receiving magnetic waves containing information via a secondary coil. In this case, the communication / control unit 220 can embed information in magnetic waves or analyze magnetic waves containing information using modulation methods such as binary phase shift keying (BPSK) or amplitude shift keying (ASK) and encoding methods such as Manchester coding or non-return-to-zero level (NZR-L) coding. Using this type of IB communication, the communication / control unit 220 can transmit and receive information over distances of up to several meters at a data transmission rate of several kbps.

[0087] The OOB module may also perform out-of-band communication via a communication antenna. For example, the communication / control unit 220 may be provided as a short-range communication module.

[0088] Examples of short-range communication modules include Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC communication modules.

[0089] The communication / control unit 220 may control the overall operation of the wireless power receiving apparatus 200. The communication / control unit 220 may perform calculations and processing of various information and control each component of the wireless power receiving apparatus 200.

[0090] The communication / control unit 220 can be implemented in a computer or similar device using hardware, software, or a combination thereof. In terms of hardware, the communication / control unit 220 can be implemented in the form of an electronic circuit that processes electrical signals and performs control functions, and in terms of software, it can be implemented in the form of a program that drives the hardware communication / control unit 220.

[0091] The load 455 may be a battery. The battery can store energy by using the power output from the power pickup unit 210. However, it is not necessary for the mobile device 450 to include a battery. For example, the battery may be provided as an external, detachable battery. As another example, the wireless power receiving apparatus 200 may include a driving means for driving various operations of the electronic device instead of a battery.

[0092] Although the mobile device 450 is illustrated as including a wireless power receiving device 200 and the base station 400 is illustrated as including a wireless power transmitting device 100, in a broad sense, the wireless power receiving device 200 can be considered the same as the mobile device 450, and the wireless power transmitting device 100 can be considered the same as the base station 400.

[0093] Hereinafter, a coil or a coil section including a coil and at least one element adjacent to the coil may also be referred to as a coil assembly, a coil cell, or a cell.

[0094] FIG. 5 is a state transition diagram for explaining a wireless power transmission procedure.

[0095] As shown in FIG. 5, power transmission from a wireless power transmission device to a receiver according to an embodiment of the present invention can be broadly divided into a selection phase 510, a ping phase 520, an identification and configuration phase 530, a negotiation phase 540, a calibration phase 550, a power transfer phase 560, and a renegotiation phase 570.

[0096] The selection phase 510 may be a transition stage (e.g., including reference numerals S502, S504, S508, S510, and S512) to which a transition is made when a specific error or specific event is detected while starting or maintaining power transmission. The specific error and specific event will be clarified in the following description. Furthermore, in the selection phase 510, the wireless power transmission apparatus may monitor whether an object is present on the surface of the interface. If the wireless power transmission apparatus detects an object on the surface of the interface, it may transition to the ping phase 520. In the selection phase 510, the wireless power transmission apparatus may transmit a very short pulse analog ping signal and detect whether an object is present in the active area on the surface of the interface based on a change in current in the transmitting coil or primary coil.

[0097] If an object is detected in the selection phase 510, the wireless power transmitter may measure a quality factor of a wireless power resonant circuit (e.g., a power transmitting coil and / or a resonant capacitor). In an embodiment of the present invention, if an object is detected in the selection phase 510, the quality factor may be measured to determine whether the wireless power receiver is placed with a foreign object in the charging area. The inductance and / or the series resistance component of the coil included in the wireless power transmitter may decrease due to environmental changes, resulting in a decrease in the quality factor value. To determine whether a foreign object is present using the measured quality factor value, the wireless power transmitter may receive a reference quality factor value measured in advance when no foreign object is present in the charging area from the wireless power receiver. The reference quality factor value received in the negotiation phase S540 may be compared with the measured quality factor value to determine whether a foreign object is present. However, in the case of a wireless power receiving device with a low reference quality factor value (for example, a specific wireless power receiving device may have a low reference quality factor value depending on the type, use, and characteristics of the wireless power receiving device), a problem occurs in that the difference between the measured quality factor value and the reference quality factor value when a foreign object is present is not large, making it difficult to determine whether a foreign object is present. Therefore, other determination factors must be further considered or other methods must be used to determine whether a foreign object is present.

[0098] In another embodiment of the present invention, when an object is detected in the selection phase 510, a quality factor value within a specific frequency range (e.g., an operating frequency range) can be measured to determine whether the wireless power receiving device is placed in the charging area together with a foreign object. The inductance and / or the series resistance component within the coil of the wireless power transmitting device can decrease due to environmental changes, thereby changing (shifting) the resonant frequency of the coil of the wireless power transmitting device. That is, the quality factor peak frequency, which is the frequency at which the maximum quality factor value is measured within the operating frequency band, can be shifted.

[0099] In phase 520, when an object is detected, the wireless power transmitter wakes up the receiver and transmits a digital ping to identify whether the detected object is a wireless power receiver. If the wireless power transmitter does not receive a response signal to the digital ping, such as a signal strength packet, from the receiver in the ping phase 520, it transitions back to the selection phase 510. Also, in the ping phase 520, the wireless power transmitter can transition to the selection phase 510 if it receives a signal indicating that power transmission is complete, such as a charging completion packet, from the receiver.

[0100] Once the ping phase 520 is complete, the wireless power transmitter transitions to the identification and configuration phase 530 to identify the receiver and collect configuration and status information of the receiver.

[0101] In the identification and configuration phase 530, the wireless power transmission device can transition to the selection phase 510 if an unexpected packet is received (unexpected packet), if a desired packet is not received for a predefined time (time out), if there is a packet transmission error (transmission error), or if no power transfer contract is set (no power transfer contract).

[0102] The wireless power transmitting device may determine whether it is necessary to enter the negotiation phase 540 based on a negotiation field value of the configuration packet received in the identification and configuration phase 530. If the determination indicates that negotiation is necessary, the wireless power transmitting device may enter the negotiation phase 540 and perform a predetermined FOD detection procedure. On the other hand, if the determination indicates that negotiation is not necessary, the wireless power transmitting device may immediately enter the power transmission phase 560.

[0103] In the negotiation phase 540, the wireless power transmission apparatus may receive a Foreign Object Detection (FOD) status packet including a reference quality factor value. Alternatively, the wireless power transmission apparatus may receive an FOD status packet including a reference peak frequency value. Alternatively, the wireless power transmission apparatus may receive a status packet including a reference quality factor value and a reference peak frequency value. In this case, the wireless power transmission apparatus may determine a quality factor threshold for FOD detection based on the reference quality factor value. Alternatively, the wireless power transmission apparatus may determine a peak frequency threshold for FOD detection based on the reference peak frequency value.

[0104] The wireless power transmission device can detect whether an FO exists in the charging area using the determined quality factor threshold for FO detection and a currently measured quality factor value (a quality factor value measured before the ping phase), and can control power transmission according to the FO detection result. For example, if an FO is detected, power transmission may be interrupted, but is not limited to this.

[0105] The wireless power transmission device can detect whether an FO exists in the charging area using the determined peak frequency threshold for FO detection and the currently measured peak frequency value (the peak frequency value measured before the ping phase), and can control power transmission according to the FO detection result. For example, if an FO is detected, power transmission may be interrupted, but is not limited to this.

[0106] If FOD is detected, the wireless power transmitter may return to the selection phase 510. On the other hand, if FOD is not detected, the wireless power transmitter may go through the correction phase 550 and enter the power transmission phase 560. In particular, if FOD is not detected, the wireless power transmitter may determine the strength of power received at the receiving end in the correction phase 550 and measure the power loss at the receiving end and the transmitting end to determine the strength of power transmitted at the transmitting end. That is, the wireless power transmitter may predict power loss based on the difference between the transmission power of the transmitting end and the reception power of the receiving end in the correction phase 550. According to an embodiment, the wireless power transmitter may correct the threshold for FOD detection to reflect the predicted power loss.

[0107] In the power transmission phase 560, the wireless power transmission device can transition to the selection phase 510 if an unexpected packet is received (unexpected packet), if a desired packet is not received for a predefined time (time out), if a violation of the set power transmission contract occurs (power transfer contract violation), or if charging is completed.

[0108] Furthermore, in the power transmission phase 560, if the power transmission contract needs to be reconfigured due to a change in the state of the wireless power transmission device, the wireless power transmission device may transition to a renegotiation phase 570. At this time, if the renegotiation is successfully completed, the wireless power transmission device may return to the power transmission phase 560.

[0109] The power transmission contract may be set based on the status and characteristic information of the wireless power transmitter and the receiver. For example, the status information of the wireless power transmitter may include information on the maximum transmittable power amount, information on the maximum number of receivers that can be accommodated, etc., and the status information of the receiver may include information on required power, etc.

[0110] FIG. 6 illustrates a power control method according to one embodiment.

[0111] 6, in the power transmission phase 560, the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200 can control the amount of power transmitted by communicating in parallel with power transmission and reception. The wireless power transmitting apparatus and the wireless power receiving apparatus operate at a specific control point. The control point indicates the combination of voltage and current provided at the output of the wireless power receiving apparatus when power transmission is performed.

[0112] More specifically, the wireless power receiving device selects a desired control point (e.g., a desired output current / voltage, a temperature at a specific location of the mobile device, etc.), and then determines an actual control point where the wireless power receiving device is currently operating. The wireless power receiving device can calculate a control error value using the desired control point and the actual control point, and transmit the calculated control error value to the wireless power transmitting device as a control error packet.

[0113] The wireless power transmitter can then control power transfer by setting / controlling a new operating point (amplitude, frequency, and duty cycle) using the received control error packet. Therefore, the control error packet is transmitted / received at regular time intervals during the power transfer phase. In one embodiment, the wireless power receiver can transmit a control error packet by setting a negative value for the control error when attempting to reduce the current of the wireless power transmitter and a positive value when attempting to increase the current. In this way, in the induction mode, the wireless power receiver can control power transfer by transmitting a control error packet to the wireless power transmitter.

[0114] The resonant mode described below can operate in a different manner from the inductive mode. In the resonant mode, one wireless power transmitter must be able to simultaneously serve multiple wireless power receivers. However, when controlling power transmission as in the inductive mode, the transmitted power is controlled through communication with one wireless power receiver, which can make it difficult to control power transmission to additional wireless power receivers. Therefore, in the resonant mode of the present invention, the wireless power transmitters transmit a common base power, and the wireless power receivers control the amount of power they receive by controlling their own resonant frequencies. However, the method described in FIG. 6 does not completely exclude this resonant mode operation, and additional transmission power can also be controlled using the method described in FIG. 6.

[0115] 7 is a block diagram of a wireless power transmission device according to another embodiment. This may belong to a wireless power transmission system of a magnetic resonance type or a shared mode. The shared mode refers to a mode in which one-to-multiple communication and charging are performed between a wireless power transmission device and a wireless power receiving device. The shared mode is realized by a magnetic induction type or a resonance type.

[0116] 7, the wireless power transmitting device 700 may include at least one of a cover 720 that covers the coil assembly, a power adapter 730 that supplies power to a power transmitting unit 740, the power transmitter 740 that transmits wireless power, or a user interface 750 that provides progress of power transmission and other related information. In particular, the user interface 750 may be optionally included or may be included as another user interface 750 of the wireless power transmitting device 700.

[0117] The power transmitter 740 may include at least one of a coil assembly 760 , an impedance matching circuit 770 , an inverter 780 , a communication unit 790 , or a control unit 710 .

[0118] The coil assembly 760 includes at least one primary coil that generates a magnetic field and may also be referred to as a coil cell.

[0119] The impedance matching circuit 770 can provide impedance matching between the inverter and the primary coil. The impedance matching circuit 770 can generate a resonance at a suitable frequency to boost the primary coil current. In a multi-coil power transmitter 740, the impedance matching circuit can also include a multi-flex that routes signals from the inverter to a subset of the primary coils. The impedance matching circuit can also be referred to as a "tank circuit."

[0120] The impedance matching circuit 770 may include a capacitor, an inductor, and a switching element for switching their connections. Impedance matching may be performed by detecting a reflected wave of wireless power transmitted through the coil assembly 760 and switching the switching element based on the detected reflected wave to adjust the connection state of the capacitor or inductor, adjust the capacitance of the capacitor, or adjust the inductance of the inductor. In some cases, the impedance matching circuit 770 may be omitted, and this specification also includes an embodiment of the wireless power transmission apparatus 700 in which the impedance matching circuit 770 is omitted.

[0121] The inverter 780 can convert a DC input to an AC signal. The inverter 780 can be driven in a half-bridge or full-bridge configuration to generate a pulse wave with an adjustable frequency and duty cycle. The inverter can also include multiple stages to adjust the input voltage level.

[0122] The communication unit 790 can communicate with the power receiver. The power receiver performs load modulation to communicate requests and information to the power transmitter. Thus, the power transmitter 740 can monitor the amplitude and / or phase of the current and / or voltage in the primary coil to demodulate the data transmitted by the power receiver using the communication unit 790.

[0123] The power transmitter 740 can also control the output power to transmit data via the communication unit 790 using a frequency shift keying (FSK) method or the like.

[0124] The control unit 710 can control communication and power transfer of the power transmitter 740. The control unit 710 can control power transmission by adjusting the aforementioned operating point, which can be determined by, for example, at least one of the operating frequency, duty cycle, and input voltage.

[0125] The communication unit 790 and the control unit 710 may be provided as separate units / elements / chipsets or may be provided as one unit / element / chipset.

[0126] 8 shows a wireless power receiving device according to another embodiment, which belongs to a magnetic resonance type or shared mode wireless power transmitting system.

[0127] 8, the wireless power receiving device 800 may include at least one of a user interface 820 that provides the progress of power transfer and other related information, a power receiving unit 830 that receives wireless power, a load circuit 840, or a base 850 that supports and covers the coil assembly. In particular, the user interface 820 may be optionally included or may be included as another user interface 82 of the power receiving equipment.

[0128] The power receiver 830 may include at least one of a power converter 860 , an impedance matching circuit 870 , a coil assembly 880 , a communication unit 890 , or a control unit 810 .

[0129] The power converter 860 can convert the AC power received from the secondary coil into a voltage and current suitable for the load circuit. In one embodiment, the power converter 860 includes a rectifier. The rectifier can rectify the received wireless power and convert it from AC to DC. The rectifier can convert AC to DC using a diode or transistor and smooth it using a capacitor and resistor. The rectifier can be a full-wave rectifier, a half-wave rectifier, a voltage multiplier, or the like, realized by a bridge circuit or the like. Furthermore, the power converter can adapt the reflected impedance of the power receiver.

[0130] The impedance matching circuit 870 may provide impedance matching between the combination of the power converter 860 and the load circuit 870 and the secondary coil. In one embodiment, the impedance matching circuit may generate a resonance around 100 kHz, which can enhance power transfer. The impedance matching circuit 870 may be configured with a capacitor, an inductor, and a switching element that switches a combination of these. Impedance matching may be performed by controlling the switching elements of the circuit that constitutes the impedance matching circuit 870 based on the voltage value, current value, power value, frequency value, etc. of the received wireless power. In some cases, the impedance matching circuit 870 may be omitted, and this specification also includes an embodiment of the wireless power receiving apparatus 200 in which the impedance matching circuit 870 is omitted.

[0131] The coil assembly 880 includes at least one secondary coil and may optionally further include elements to shield metallic portions of the receiver from magnetic fields.

[0132] The communication unit 890 may perform load modulation to communicate requests and other information to the power transmitter.

[0133] To this end, the power receiver 830 may also switch in resistors or capacitors to change the reflected impedance.

[0134] The control unit 810 can control the received power. To this end, the control unit 810 can determine / calculate the difference between the actual operating point of the power receiver 830 and the desired operating point. The control unit 810 can then adjust / reduce the difference between the actual operating point and the desired operating point by adjusting the reflected impedance of the power transmitter and / or requesting an adjustment of the operating point of the power transmitter. When this difference is minimized, optimal power reception can be achieved.

[0135] The communication unit 890 and the control unit 810 may be provided as separate components / chipsets or may be provided as one component / chipset.

[0136] Figure 9 shows a communication frame structure according to one embodiment, which may be a communication frame structure in shared mode.

[0137] 9, different types of frames can be used together in the shared mode. For example, in the shared mode, a slotted frame having multiple slots as shown in (A) and a free format frame without a specific format as shown in (B) can be used. More specifically, the slotted frame is a frame for transmitting a short data packet from the wireless power receiving apparatus 200 to the wireless power transmitting apparatus 100, and the free format frame does not have multiple slots and can therefore transmit a long data packet.

[0138] Meanwhile, the slot frame and the free format frame may be renamed to various names by those skilled in the art. For example, the slot frame may be renamed to a channel frame, and the free format frame may be renamed to a message frame.

[0139] More specifically, the slot frame may include a sync pattern indicating the start of a slot, a measurement slot, nine slots, and an additional sync pattern having the same time interval before each of the nine slots.

[0140] Here, the additional sync pattern is a sync pattern different from the sync pattern indicating the start of a frame described above. More specifically, the additional sync pattern may indicate information about adjacent slots (i.e., two consecutive slots located on both sides of the sync pattern) rather than indicating the start of a frame.

[0141] A sync pattern may be located between each two consecutive slots among the nine slots, in which case the sync pattern provides information about the two consecutive slots.

[0142] The nine slots and the sync patterns provided before each of the nine slots may have the same time interval. For example, the nine slots may have a time interval of 50 ms. The nine sync patterns may also have a time length of 50 ms.

[0143] On the other hand, the free format frame as shown in (B) may not have a specific form other than a sync pattern indicating the start of the frame and a measurement slot. That is, the free format frame is intended to perform a different role from the slot frame, for example, to communicate a long data packet (e.g., an additional owner information packet) between the wireless power transmitter and the wireless power receiver, or to select one of multiple coils in a wireless power transmitter configured with multiple coils.

[0144] Hereinafter, the sync pattern included in each frame will be described in more detail with reference to the drawings.

[0145] FIG. 10 is a structure of a sync pattern according to one embodiment.

[0146] As shown in Figure 10, the sync pattern consists of a preamble, a start bit, a response field, a type field, an information field, and a parity bit. In Figure 10, the start bit is shown as ZERO.

[0147] More specifically, the preamble is composed of consecutive bits, all of which may be set to 0. That is, the preamble is a bit for adjusting the time length of the sync pattern.

[0148] The number of bits constituting the preamble can be dependent on the operating frequency so that the length of the sync pattern is closest to, but not exceeding, 50 ms. For example, if the operating frequency is 100 kHz, the sync pattern will consist of two preamble bits, and if the operating frequency is 105 kHz, the sync pattern will consist of three preamble bits.

[0149] The start bit is a beat following the preamble and means zero. The zero may be a bit indicating the type of sync pattern. Here, the types of sync patterns include a frame sync containing information about a frame and a slot sync containing information about a slot. That is, the sync pattern may be a frame sync located between consecutive frames and indicating the start of a frame, or a slot sync located between consecutive slots among a plurality of slots constituting a frame and containing information about the consecutive slots.

[0150] For example, if the zero is 0, it means that the corresponding slot is a slot sync located between slots, and if it is 1, it means that the corresponding sync pattern is a frame sync located between frames.

[0151] The parity bit is the last bit of the sync pattern and indicates the number of bits constituting the data field (i.e., response field, type field, information field) of the sync pattern. For example, the parity bit can be 1 if the number of bits constituting the data field of the sync pattern is even, and 0 otherwise (i.e., odd).

[0152] The response field may contain response information of the wireless power transmitting device in response to communication with the wireless power receiving device in a slot before the sync pattern. For example, the response field may contain "00" if no communication with the wireless power receiving device is detected. The response field may also contain "01" if a communication error is detected in communication with the wireless power receiving device. The communication error may occur when two or more wireless power receiving devices attempt to access one slot and a collision occurs between the two or more wireless power receiving devices.

[0153] The response field may include information indicating whether the data packet has been correctly received from the wireless power receiving apparatus. More specifically, the response field may be set to “10” (10-not acknowledge, NAK) if the wireless power transmitting apparatus rejects the data packet, or to “11” (11-acknowledge, ACK) if the wireless power transmitting apparatus confirms the data packet.

[0154] The type field indicates the type of sync pattern. More specifically, if the sync pattern is the first sync pattern of a frame (i.e., the first sync pattern of a frame and located before the measurement slot), the type field may contain "1" to indicate that it is a frame sync.

[0155] Additionally, the type field may have a "0" to indicate that the sync pattern is a slot sync if it is not the first sync pattern in the slot frame.

[0156] Furthermore, the meaning of the value of the information field is determined by the type of sync pattern indicated by the type field. For example, if the type field is 1 (i.e., indicates frame sync), the meaning of the information field can indicate the type of frame. That is, the information field indicates whether the current frame is a slotted frame or a free-format frame. For example, if the information field is '00', it indicates a slotted frame, and if the information field is '01', it indicates a free-format frame.

[0157] Alternatively, if the type field is 0 (i.e., slot sync), the information field may indicate the status of the next slot located after the sync pattern. More specifically, the information field may have '00' if the next slot is allocated to a specific wireless power receiving device, '01' if the slot is locked for temporary use by a specific wireless power receiving device, or '10' if the slot is freely available to any wireless power receiving device.

[0158] FIG. 11 illustrates an operation state of a wireless power transmitter and a wireless power receiver in a shared mode according to an embodiment.

[0159] As shown in FIG. 11, a wireless power receiving device operating in a shared mode can operate in any one of a selection phase 1100, an introduction phase 1110, a configuration phase 1120, a negotiation phase 1130, and a power transfer phase 1140.

[0160] First, a wireless power transmitter according to an embodiment may transmit a wireless power signal to detect a wireless power receiver. That is, a process of detecting a wireless power receiver using a wireless power signal may be called analog ping.

[0161] Meanwhile, a wireless power receiving device that has received a wireless power signal may enter a selection phase 1100. The wireless power receiving device that has entered the selection phase 1100 may detect the presence of an FSK signal in the wireless power signal, as described above.

[0162] That is, the wireless power receiving device can perform communication in either the exclusive mode or the shared mode depending on whether or not an FSK signal is present.

[0163] More specifically, the wireless power receiving device can operate in a shared mode if the wireless power signal includes an FSK signal, and can operate in an exclusive mode if the wireless power signal does not include an FSK signal.

[0164] When the wireless power receiving device operates in a shared mode, the wireless power receiving device may enter an introduction phase 1110. In the introduction phase 1110, the wireless power receiving device may transmit a control information (CI) packet to the wireless power transmitting device to transmit the control information packet in the configuration phase, negotiation phase, and power transmission phase. The control information packet may have a header and information related to control. For example, the header of the control information packet may be 0X53.

[0165] In the introduction phase 1110, the wireless power receiving device attempts to request a free slot to transmit a control information (CI) packet during the following configuration phase, negotiation phase, and power transmission phase. At this time, the wireless power receiving device selects a free slot and transmits the first CI packet. If the wireless power transmitting device responds to the CI packet with an ACK, the wireless power transmitting device enters the configuration phase. If the wireless power transmitting device responds with a NACK, another wireless power receiving device is in the configuration and negotiation phases. In this case, the wireless power receiving device attempts to request a free slot again.

[0166] If the wireless power receiving device receives an ACK in response to the CI packet, the wireless power receiving device determines the location of a private slot in the frame by counting the remaining slot syncs up to the first frame sync, and in all subsequent slot-based frames, the wireless power receiving device transmits a CI packet through that slot.

[0167] If the wireless power transmitting device allows the wireless power receiving device to proceed to the configuration phase, the wireless power transmitting device provides a series of locked slots for the exclusive use of the wireless power receiving device, which ensures that the wireless power receiving device proceeds to the configuration phase without collision.

[0168] The wireless power receiving device transmits a sequence of data packets, such as two identification data packets (IDHI and IDLO), using the lock slot. Upon completing this phase, the wireless power receiving device enters the negotiation phase. In the negotiation phase, the wireless power transmitting device continuously provides the wireless power receiving device with lock slots for exclusive use. This ensures that the wireless power receiving device proceeds through the negotiation phase without collisions.

[0169] The wireless power receiving device uses the lock slot to transmit one or more negotiation data packets, which may be intermixed with proprietary data packets. Eventually, the sequence ends with a specific request (SRQ) packet. Upon completing the sequence, the wireless power receiving device enters the power transmission phase, and the wireless power transmitting device ceases providing the lock slot.

[0170] In the power transmission state, the wireless power receiving device transmits a CI packet using the assigned slot to receive power. The wireless power receiving device may include a regulator circuit. The regulator circuit may be included in the communication / control unit. The wireless power receiving device can self-regulate its reflected impedance via the regulator circuit. In other words, the wireless power receiving device can adjust the reflected impedance to transmit the amount of power required by the external load. This can prevent excessive power reception and overheating.

[0171] In shared mode, the wireless power transmitter may not adjust power in response to received CI packets (depending on the operating mode), in which case control is needed to prevent overvoltage conditions.

[0172] The following describes an apparatus and method for a wireless power transmitting device to perform communication related to power management and authentication with status and authority as a master / transmitter depending on the situation.

[0173] 1. Definition and usage of power indicators

[0174] FIG. 12 illustrates available power metrics according to one example.

[0175] As shown in FIG. 12, an available power indicator according to one embodiment refers to the power that can be provided or transmitted by a wireless power transmitting device as an output of a wireless power receiving device in a power transmission phase, and specifically includes potential power (PP), guaranteed power (GP), and target power (TP).

[0176] The potential power refers to the output power or amount of output power of a reference wireless power receiving device that a wireless power transmitting device can make available during a power transfer phase. The potential power can be fixed by design.

[0177] The guaranteed power refers to the output power or amount of output power of the reference wireless power receiving device that the wireless power transmitting device ensures at any time during the power transmission phase. The guaranteed power is negotiated before the power transmission phase, but can be maintained fixed during the power transmission phase. The guaranteed power can be at least 5 W.

[0178] Target power refers to the output power or amount of output power of a wireless power receiving device that a wireless power transmitting device provides during a power transmission phase. The target power is dynamic and may change during a power transmission phase. The supported target power may depend on the conditions under which the wireless power transmitting device operates.

[0179] FIG. 13 illustrates how each available power indicator is set during the negotiation phase according to one example.

[0180] As shown in FIG. 13, the wireless power transmitter reserves a sufficient margin between the potential power and the guaranteed power. The wireless power transmitter negotiates the guaranteed power for the expected operating conditions during the power transmission phase. For example, depending on the design and market of the wireless power transmitter, the wireless power transmitter may be configured to negotiate the guaranteed power at 50% of the potential power. Such guaranteed power negotiation is performed by the communication / control unit 120 in FIG. 4 or the control unit 710 in FIG. 7.

[0181] The wireless power transmitting device can set the negotiated guaranteed power as the initial target power. The target power is updated according to the actual power that the wireless power receiving device draws during the power transmission phase (supported by the ambient conditions in which the wireless power transmitting device is currently charging). Meanwhile, the initial target power can also be set by other methods, as shown in FIG. 14. The setting of the initial target power can be performed by the communication / control unit 120 in FIG. 4 or the control unit 710 in FIG. 7.

[0182] FIG. 14 illustrates how each available power indicator is set during the negotiation phase according to another example.

[0183] As shown in Fig. 14, the wireless power transmitter can set the potential power to an initial target power. The target power is updated according to the actual condition of the wireless power transmitter. The initial target power is set by the communication / control unit 120 in Fig. 4 or the control unit 710 in Fig. 7.

[0184] In the power transmission phase, the wireless power transmitting device and the receiving device can perform power control based on the available power index or adjust the available power index as needed. Hereinafter, the power control or adjustment of the available power index is performed by the communication / control unit 120 in FIG. 4 or the control unit 710 in FIG. 7.

[0185] For example, the wireless power transmitter may assume control authority at a level exceeding the guaranteed power level. If conditions permit, the wireless power transmitter may adapt to a power level according to an existing control error and update the target power to the received power of the wireless power receiver.

[0186] In one aspect, a wireless power transmitting device can adjust its target power by reporting a request for communication (RFC). RFC can be replaced with terms such as request for renegotiation (RFR), request for auxiliary transport (RFA), or attention. Even if the terminology differs, the functionality related to available power indicators or PTx-initiated communication is the same or similar. The wireless power transmitting device may wish to decrease its target power based on deteriorated ambient charging conditions. Alternatively, the wireless power transmitting device may wish to increase its target power based on improved ambient charging conditions. During this renegotiation phase, the wireless power receiving device can acknowledge the target power of the wireless power transmitting device and adjust its operating mode as necessary.

[0187] In another aspect, if conditions change during the power transmission phase, the wireless power transmitter can adapt the target power accordingly. If the target power changes, the wireless power transmitter can send an alert to the wireless power receiver. This is an optional feature for the wireless power receiver, but may be a required feature for the wireless power transmitter. The wireless power receiver can also request the wireless power transmitter to apply an alert during the negotiation phase. If the actual power is greater than the target power, the wireless power transmitter can reduce or limit the actual power transmission. The wireless power transmitter cannot suddenly reduce the actual power transmission without a warning or alert. The operation of sending an alert is performed by the communication / control unit 120 of FIG. 4 or the communication unit 790 of FIG. 7.

[0188] As another example, the wireless power transmitting device may report "NAK" in response to a received power (RP) packet (RPP) if it is unable to maintain the guaranteed power. This is an exceptional case, such as a very poor coupling environment, a high temperature, or the insertion of a foreign object. The NAK report is performed by the communication / control unit 120 in FIG. 4 or the communication unit 790 in FIG. 7. Here, the wireless power receiving device may send an end power transfer (EPT) packet, whose value may be 0x08. The transmission of the EPT packet is performed by the communication / control unit 220 in FIG. 4 or the communication unit 890 in FIG. 8.

[0189] In this case, the wireless power transmitting device restarts power transmission in order to perform foreign object detection before restarting.

[0190] As another example, the wireless power receiving device can handle guaranteed power. A load can be configured so that the rectified voltage is sufficiently high at the guaranteed power. If the requested power is greater than or equal to the guaranteed power and the wireless power transmitting device ignores the positive control error, the wireless power transmitting device can continue transmitting power, and an EPT packet (0x08) is not required.

[0191] FIG. 15 is a diagram illustrating a process of performing power control based on each available power indicator in a power transmission phase according to an example.

[0192] As shown in Fig. 15, the wireless power transmitter can change (increase or decrease) the target power depending on the current surrounding charging conditions during the power transmission phase and the renegotiation phase. That is, the target power can be changed during the renegotiation phase, and power transmission continues at the previous power level during the renegotiation phase. Such change in the target power is performed by the communication / control unit 120 in Fig. 4 or the control unit 710 in Fig. 7.

[0193] FIG. 16 is a diagram illustrating a process of performing power control based on each available power indicator in a power transmission phase according to another example.

[0194] As shown in FIG. 16, the wireless power transmitting device can change (increase or decrease) the available power index (eg, target power) according to the current surrounding charging conditions during power transmission.

[0195] An embodiment in which the power indicators available to the wireless power transmitting device and the wireless power receiving device are changed based on communication initiated by the wireless power transmitting device is as follows.

[0196] The change of the available power indicator according to the first embodiment may include the steps of: a wireless power transmitting device sending a "request for communication (RFC)" to the wireless power receiving device in response to the RP or CE packet to alert the wireless power receiving device of a change in the previously negotiated first available power indicator; a wireless power receiving device sending a response signal to the wireless power transmitting device indicating that the wireless power receiving device is ready to receive such communication from the wireless power transmitting device; a wireless power transmitting device sending a packet related to a second available power indicator to the wireless power receiving device; and a wireless power receiving device adjusting its operation mode according to the second available power indicator and sending an ACK to the wireless power transmitting device. The response signal indicating readiness may be a poll or an ACK packet. The second available power indicator may include at least one of potential power, guaranteed power, and target power.

[0197] For example, if the second available power indicator is guaranteed power, the wireless power transmitting apparatus may transmit a packet related to the guaranteed power to the wireless power receiving apparatus after receiving a response signal from the wireless power receiving apparatus, and the wireless power receiving apparatus may adjust its operation mode according to the guaranteed power. The packet related to the guaranteed power may include a capability packet of the wireless power transmitting apparatus indicating the guaranteed power value, as shown in FIG.

[0198] As another example, if the second available power indicator is a target power, the wireless power transmitting apparatus may transmit a packet related to the target power to the wireless power receiving apparatus after receiving a response signal from the wireless power receiving apparatus, and the wireless power receiving apparatus may adjust its operation mode according to the target power. The packet related to the target power may include a packet indicating a target power value as shown in FIG. 19 or 20.

[0199] Meanwhile, RFC refers to a renegotiation request (RFR), and changing the available power indicator according to the second embodiment may further include a step in which the wireless power receiving device that received the RFC in the first embodiment sends an ACK, and then enters a renegotiation phase to change the power contract according to the available power indicator.

[0200] The transmission of the RFC, target power packet, and the reception of the response signal are performed by the communication / control unit 120 in Fig. 4 or the communication unit 790 in Fig. 7. The transmission of the response signal is performed by the communication / control unit 220 in Fig. 4 or the communication unit 890 in Fig. 8. The adjustment of the operation mode according to the target power is performed by the communication / control unit 220 in Fig. 4 or the control unit 810 in Fig. 8.

[0201] 2. Wireless power transmitter signals or packets used in conjunction with available power indicators

[0202] (1) Bit pattern response

[0203] In relation to the available power indicator, the wireless power transmitting device can transmit a bit pattern response to the wireless power receiving device in response to the wireless power receiving device transmitting a communication packet (e.g., an RP packet). The bit pattern response is generated and transmitted by the communication / control unit 120 of FIG. 4 or the communication unit 790 of FIG. 7.

[0204] For example, the bit pattern responses may include ACK, NAK, ND, and RFR. For example, RFR is 8 bits and its value is set to "00110011"b. Meanwhile, the remaining bit pattern responses may also have values ​​of ACK ('111111'b), NAK ('0000000'b), and ND ('01010101'b). In this case, it can be seen that the bit patterns are clearly distinguishable between different bit pattern responses.

[0205] The wireless power transmitting device can request the wireless power receiving device to enter a renegotiation phase by transmitting a bit pattern response (RFR) to the wireless power receiving device to update the target power. The target power is updated to increase or decrease the requested power to reflect the current surrounding charging conditions. The protocol for the RFR transmission procedure is shown in FIG. 17.

[0206] FIG. 17 is a protocol for the RFR transmission procedure according to one embodiment.

[0207] As shown in Fig. 17, the wireless power transmitting device transmits a bit pattern response RFR 1705 after an RPP 1700 to request the wireless power receiving device to enter a renegotiation phase. The RFR is transmitted by the communication / control unit 120 of Fig. 4 or the communication unit 790 of Fig. 7. The wireless power receiving device then transmits a renegotiation (RNG) packet 1710 to the wireless power transmitting device, and the wireless power transmitting device transmits an ACK 1715 to the wireless power receiving device. The renegotiation packet is transmitted by the communication / control unit 220 of Fig. 4 or the communication unit 890 of Fig. 8. The response of the wireless power transmitting device is not only possible for the RPP, but also allows the existing "NAK" to be reused for the RFR by defining a new response of the wireless power transmitting device to a CE packet.

[0208] As another example, the bit pattern response may include ACK, NAK, ND, and RFC. For example, RFC is 8 bits and its value is set to "00110011"b. Meanwhile, the remaining bit pattern responses may also have values ​​of ACK ('111111'b), NAK ('0000000'b), and ND ('01010101'b). In this case, it can be seen that the bit patterns are clearly distinguishable between different bit pattern responses. That is, because the bit pattern response is defined as a repetitive bit pattern, quick recognition, redundancy, and simple implementation are possible. For example, if four bits received by a wireless power receiving device exactly match one of predefined bit patterns, the wireless power receiving device can be confident about the meaning of the bit pattern response after (or at the time of) receiving the first four bits. Although the wireless power receiving device may miss some of the first bits, it can recognize the pattern and correct any flipped bits.

[0209] The RFC transmission procedure includes the steps of: when a wireless power transmitter needs to communicate, it transmits an alert to the wireless power receiver in response to an RP packet or a CE packet; when the wireless power receiver is in a condition to listen to the wireless power transmitter, the wireless power receiver transmits an ACK; the wireless power transmitter responds with information about the target power that is actually supported; and the wireless power receiver adapts to the new situation of the new target power and then transmits the ACK. Here, the message of the wireless power transmitter and the response and operation of the wireless power receiver are defined by the message of the wireless power transmitter. For example, in the case of information about the target power, the wireless power receiver adjusts its operation mode and then transmits the ACK.

[0210] As another example, the bit pattern response can include ACK, NAK, ND, and RFA (request for auxiliary transport). For example, RFA is 8 bits and its value is set to "00110011"b. Meanwhile, the remaining bit pattern responses can also have values ​​of ACK ('111111'b), NAK ('0000000'b), and ND ('01010101'b). In this case, it can be seen that the bit patterns are clearly distinguished between different bit pattern responses.

[0211] The RFA transmission procedure includes the steps of: when the wireless power transmitter needs to communicate, sending an alert to the wireless power receiver in response to the RP packet; when the wireless power receiver is in a condition to hear the wireless power transmitter, the wireless power receiver sends an ACK; the wireless power transmitter responds with information about the target power actually supported; and after the wireless power receiver adapts to the new situation of the new target power, sending an ACK. For compatibility with legacy Qi wireless power receivers, the wireless power receiver can only send an RFA in response to the RP packet in Mode 0.

[0212] (2) RFA packet of the wireless power transmitter

[0213] The RFA is not a bit pattern response, but is defined as an RFA packet indicated by a header for the RFA, as shown in FIG. 18. For example, if the request field is set to '11111111'b, the RFA indicates a request of the wireless power transmitter for data transmission, and if the request field is set to '00000000'b, the RFA indicates a request of the wireless power transmitter for auxiliary data transmission. Here, auxiliary transport includes data transport and auxiliary data transport. The header for data transport indicates the type of data packet. The header for auxiliary data transport indicates that the corresponding packet is auxiliary data that can be parsed by an upper layer application.

[0214] (3) Capability packet of the wireless power transmitter

[0215] The available power indicator may be transmitted in a capability packet of the wireless power transmitting device. The transmission of the available power indicator or the capability packet may be performed by the communication / control unit 120 of FIG. 4 or the communication unit 790 of FIG.

[0216] FIG. 19 is a structure of a wireless power transmitter capability packet including an available power indicator according to one embodiment.

[0217] As shown in FIG. 19, the performance packet is three bytes, the first byte B0 contains the power class and (target) guaranteed power value, the second byte B1 contains the reserved and potential power value, and also contains reserved, WPID, and Not REs Sens.

[0218] In the negotiation phase, the (target) guaranteed power value may indicate the output power or amount of output power of the reference wireless power receiving device that the wireless power transmitting device ensures possible at any time during the power transmission phase.

[0219] In the renegotiation phase, the (target) guaranteed power value may refer to the output power or amount of output power of the wireless power receiving device that the wireless power transmitting device wishes to renegotiate with under current ambient conditions.

[0220] (4) Target power packet of the wireless power transmitter

[0221] The target power value can be transmitted in a target power packet of the wireless power transmitting device, which is transmitted by the communication / control unit 120 of FIG. 4 or the communication unit 790 of FIG.

[0222] FIG. 20 shows the structure of a target power packet of a wireless power transmitting device according to one embodiment.

[0223] As shown in FIG. 20, the target power packet may be one byte, some of which may be reserved bits and the remaining part may be a field indicating the target power value. For example, the reserved bits may be two bits and the field indicating the target power value may be six bits. The target power value may refer to the output power or amount of output power of the wireless power receiving device that the wireless power transmitting device provides during the power transmission phase. The target power value is dynamic and may change during the power transmission phase. The supported target power may depend on the conditions under which the wireless power transmitting device operates.

[0224] (5) General Request Packet (GRP) and Specific Request Packet (SRP)

[0225] A wireless power receiving device can use a general request packet or a specific request packet to obtain the value of the current guaranteed available power (or target power). The generation and transmission of the general or specific request packet is performed by the communication / control unit 220 of FIG. 4 or the communication unit 890 of FIG. 8.

[0226] For example, the wireless power receiving device may use the general request packet to read the performance packet of the wireless power transmitting device, where the target power value may be the same as the guaranteed power value included in the performance packet. Alternatively, the wireless power receiving device may use the general request packet to obtain information about the supported target power.

[0227] As another example, the wireless power receiving device can read the target power value (or guaranteed power value) of the wireless power transmitting device using a specific request packet, which is used to obtain a yes / no answer and to request that the target power be maintained constant in relation to the available power indicator without abrupt decreases.

[0228] (6) Response packet of the wireless power receiving device

[0229] The response packet of the wireless power receiving device can be generated and transmitted by the communication / control unit 220 of FIG. 4 or the communication unit 890 of FIG. 8 in association with the available power indicator.

[0230] FIG. 21 shows a structure of a response packet of a wireless power receiving device according to an embodiment.

[0231] As shown in FIG. 21, the response packet may be one byte, with the entire 8 bits being a response field indicating multiple responses.

[0232] For example, if the response field is set to '11111111'b, the response packet indicates an ACK; if the response field is set to '00000000'b, the response packet indicates a NAK; and if the response field is set to '01010101'b, the response packet indicates an ND.

[0233] As another example, if the response field is set to '11111111'b, the response packet indicates an ACK; if the response field is set to '00000000'b, the response packet indicates a NAK; if the response field is set to '01010101'b, the response packet indicates an ND; and if the response field is set to '00110011'b, the response packet may indicate an RFA.

[0234] (6) Response packet of the wireless power transmitter

[0235] A response packet of the wireless power transmitter can be used in relation to the available power indicator. The response packet of the wireless power transmitter is generated and transmitted by the communication / control unit 120 of Fig. 4 or the communication unit 790 of Fig. 7. Fig. 22 shows the structure of a response packet of the wireless power transmitter according to one embodiment.

[0236] 22, the response packet may be one byte, and the entire 8 bits may be a response field indicating multiple responses, which has the same structure as the response packet of the wireless power receiving apparatus in FIG.

[0237] As an example, if the response field is set to '11111111'b, the response packet indicates an ACK; if the response field is set to '00000000'b, the response packet indicates a NAK; if the response field is set to '01010101'b, the response packet indicates an ND; and if the response field is set to '00110011'b, the response packet indicates an RFA.

[0238] 3. PTx-initiated communication method regarding available power indicators

[0239] Communication initiated by a wireless power transmission device can be used in authentication and power management functions. In authentication initiated by a wireless power transmission device, the wireless power transmission device must start authentication as an initiator by transmitting a data stream of a request message at a timing required by the wireless power transmission device.

[0240] In power management initiated by a wireless power transmission device, the wireless power transmission device needs to renegotiate the power level depending on the charging environment at the timing required by the wireless power transmission device.

[0241] Therefore, communication initiated by a wireless power transmitter must provide a means to request attention from a wireless power receiver. That is, when a wireless power transmitter attempts to transmit data to a wireless power receiver, the aforementioned bit pattern response (e.g., RFR, RFC, RFA) is used. The bit pattern response provides the wireless power transmitter with an opportunity to transmit data. However, even in this case, the wireless power receiver can still maintain control of communication by allowing / disallowing the request from the wireless power transmitter.

[0242] If the wireless power transmission device is to transmit data, a corresponding protocol must also be defined. For example, in communication initiated by the wireless power transmission device, an auxiliary transport or auxiliary data transport protocol can be used for data transmission.

[0243] FIG. 23 is a flowchart illustrating a wireless power transmitting device transmitting information about available power indicators based on an auxiliary transmission protocol according to one embodiment.

[0244] As shown in FIG. 23, the auxiliary transmission protocol is broadly divided into steps (S2300 and S2305) in which the wireless power transmission apparatus requests auxiliary transmission, and steps (S2310 and S2315) in which the wireless power transmission apparatus performs auxiliary transmission in response to the auxiliary transmission request.

[0245] First, in the step of requesting additional transmission, the wireless power receiving device transmits an RP packet (RPP) to the wireless power transmitting device (S2300). The RP packet is generated and transmitted by the communication / control unit 220 of FIG. 4 or the communication unit 890 of FIG. 8. The wireless power transmitting device transmits an RFA to the wireless power receiving device (S2305). The RFA is generated and transmitted by the communication / control unit 120 of FIG. 4 or the communication unit 790 of FIG. 7. The RFA may be a bit pattern response or an RFA packet. The purpose of the wireless power transmitting device transmitting the RFA may be to transmit data of the wireless power transmitting device to the wireless power receiving device using communication initiated by the wireless power transmitting device. Here, the data transmitted by the wireless power transmitting device may include a packet related to an available power indicator. For example, the packet related to the available power indicator may include information on at least one of a target power, a guaranteed power, and a potential power. In this case, the purpose of the wireless power transmitting device transmitting the RFA may be to request a renegotiation for a change in the available power indicator (eg, an increase or decrease in guaranteed power).

[0246] Next, in the step of performing additional transmission, the wireless power receiving apparatus that has received the RFA transmits a response packet for the RFA to the wireless power transmitting apparatus (S2310). The generation and transmission of the response packet for the RFA is performed by the communication / control unit 220 of FIG. 4 or the communication unit 890 of FIG. 8. As an example, the response packet for the RFA may be an ACK packet indicating that the wireless power receiving apparatus has acknowledged the request from the wireless power transmitting apparatus. As another example, the response packet for the RFA may indicate that the wireless power receiving apparatus is in a state of listening to the wireless power transmitting apparatus.

[0247] Then, the wireless power transmitting device transmits a packet regarding the available power indicator to the wireless power receiving device (S2315). The generation and transmission of the packet regarding the available power indicator is performed by the communication / control unit 120 in FIG. 4 or the communication unit 790 in FIG.

[0248] FIG. 24A is a detailed diagram of the ATX (or ATD) stage for performing additional transmission according to one embodiment.

[0249] As shown in FIG. 24A, the ATX (or ATD) step (S2400) of performing additional transmission may be paired with two steps, such as a step (ATX_PRx, S2405) of performing additional transmission by the wireless power receiving apparatus and a step (ATX_PTx, S2410) of performing additional transmission by the wireless power transmitting apparatus. In ATX_PRx, additional data or additional data packets or response (ACK / NAK / RFA) packets of the wireless power receiving apparatus are transmitted. The generation and transmission of the additional data or additional data packets or response (ACK / NAK / RFA) packets of the wireless power receiving apparatus are performed by the communication / control unit 220 of FIG. 4 or the communication unit 890 of FIG. 8.

[0250] In ATX_PTx, additional data or additional data packets, or response (ACK / NAK / RFA) packets, or bit pattern responses of the wireless power transmission device are transmitted. ATX can also be called ADT (auxiliary data transport) or ADC (auxiliary data control transport). The generation and transmission of the additional data or additional data packets, or response (ACK / NAK / RFA) packets, or bit pattern responses of the wireless power transmission device are performed by the communication / control unit 120 in FIG. 4 or the communication unit 790 in FIG. 7.

[0251] FIG. 24B is a detailed diagram of the ATX (or ATD) step for performing additional transmission according to another embodiment.

[0252] As shown in FIG. 24B, the ATX (or ATD) step (S2420) of performing additional transmission may be paired with two steps, such as a step (S2525) of the wireless power transmitting apparatus (or wireless power receiving apparatus) performing additional transmission and a step (S2530) of the wireless power receiving apparatus (or wireless power transmitting apparatus) transmitting an ACK / NAK or bit pattern response. The header of the ADT packet may indicate Header A or Header B. If the CE value is 0 or close to 0, the ADT may be transmitted at intervals of, for example, 500 ms. Alternatively, if the CE value is equal to or greater than a certain value, the transmission of the ADT may be omitted. A single ADT (ADT data pair) may be transmitted between two adjacent CE packets.

[0253] FIG. 25 is a flowchart illustrating a process for transmitting information about an available power index by a wireless power transmitting device based on an additional transmission protocol according to another embodiment.

[0254] As shown in FIG. 25, the wireless power receiving apparatus transmits a CE packet and an RP packet to the wireless power transmitting apparatus (S2500). The CE packet and the RP packet are generated and transmitted by the communication / control unit 220 of FIG. 4 or the communication unit 890 of FIG. 8. The wireless power transmitting apparatus transmits a bit pattern response RFC to the wireless power receiving apparatus (S2505). This allows the wireless power transmitting apparatus to get the attention of the wireless power receiving apparatus and request that the wireless power transmitting apparatus start communication. In this embodiment, it is assumed that the wireless power transmitting apparatus transmits the bit pattern response RFC for the purpose of changing the available power indicator. In this case, the wireless power transmitting apparatus performs a procedure for changing the available power indicator in the renegotiation phase. Depending on the embodiment, the RFC may be replaced with an RFA, RFR, or ATN.

[0255] On the other hand, the wireless power receiving apparatus transmits a response packet (GR (general request) packet) to the wireless power transmitting apparatus in response to the RFC (S2510) to inquire about the reason for starting communication by the wireless power transmitting apparatus. This is also called a poll. The generation and transmission of the response packet to the RFC is performed by the communication / control unit 220 in FIG. 4 or the communication unit 890 in FIG. 8.

[0256] As an example, a GR packet may be used as the response packet, and the GR packet may have, for example, the structure shown in Fig. 26. As shown in Fig. 26, the GR packet includes a request field. The wireless power receiving device polls the reason for the attention request by transmitting a GR packet including a request field indicating a reason for attention (RA) to the wireless power transmitting device. The request field may be the header of the RA packet.

[0257] Referring again to FIG. 25, the wireless power transmitting apparatus notifies the wireless power receiving apparatus that renegotiation is required due to a change in the available power indicator (S2515). A separate RA packet can be used for step S2515. Here, the RA packet can have the structure shown in FIG. 27. As shown in FIG. 27, the RA packet is 1 byte and can indicate the reason for the attention request. For example, b0=1 indicates renegotiation, and b1=1 indicates ADT data stream (e.g., authentication) transmission. Also, b2 to b7 can be reserved bits. RA can also be referred to as a reason for request (RR). The generation and transmission of the RA packet is performed by the communication / control unit 120 of FIG. 4 or the communication unit 790 of FIG. 7.

[0258] 25 again, after determining whether to accept the renegotiation request, the wireless power receiving apparatus transmits an ACK packet as shown in FIG. 28 indicating permission (S2520), and transmits a CE packet for the ongoing power transmission to the wireless power transmitting apparatus (S2525). The ACK / NAK packet is 1 byte of information, and if its value is '11111111'b, it indicates ACK (the RA packet or ADT data packet was received without any errors), and if its value is '00000000'b, it indicates NAK (an error occurred in receiving the RA packet or ADT data packet).

[0259] The wireless power receiving apparatus then transmits a renegotiation packet to the wireless power transmitting apparatus (S2530). The wireless power transmitting apparatus responds with an ACK (S2535). The wireless power receiving apparatus then transmits a specific request packet to the wireless power transmitting apparatus to receive the required packets (S2540). The wireless power transmitting apparatus and the receiving apparatus then enter a renegotiation phase, exchange the required packets, and change the available power indicator.

[0260] Meanwhile, the communication initiated by the wireless power transmitting apparatus may be performed in a manner in which the wireless power receiving apparatus inquires whether there is a data stream to be transmitted to the wireless power transmitting apparatus.

[0261] To this end, the wireless power receiving apparatus can transmit an ADT data packet including a start of data stream (SOD) or an end of data stream (EOD). For example, a start of data stream (SOD) packet can be added to the beginning of the ADT data stream. Alternatively, an EOD packet can be added to the end of the data stream. The structure of an SOD / EOD packet is shown in FIG. 29, for example. The generation and transmission of an ADT data packet including an SOD or EOD is performed by the communication / control unit 220 of FIG. 4 or the communication unit 890 of FIG. 8.

[0262] 30 is a diagram showing an ADT data transmission procedure according to one embodiment, in which a wireless power receiving apparatus transmits ADT data to a wireless power transmitting apparatus using an ADT transmission protocol.

[0263] 30, in the power transmission phase, the wireless power receiving device transmits a CE packet to the wireless power transmitting device, and then transmits an SOD to the wireless power transmitting device (S3000). If the wireless power transmitting device successfully receives the CE packet, it transmits an ACK, which is a bit pattern response, in response (S3005). The wireless power receiving device plays the role of a master that transmits a message to the wireless power transmitting device.

[0264] After successfully transmitting the 0th ADT data packet (ADT_PRx(0)) (S3010), the wireless power receiving device receives an ACK (S3015). The process of transmitting the ADT data packet may belong to the power transmission phase, and in this case, a CE packet may be transmitted from the wireless power receiving device to the wireless power transmitting device between the ADT data packets or periodically.

[0265] Meanwhile, the wireless power transmitting apparatus fails to receive the first ADT data packet (ADT_PRx(1)) (S3020) and transmits a NAK to the wireless power receiving apparatus (S3025). Thereafter, the wireless power receiving apparatus retransmits the first ADT data packet (ADT_PRx(1)) (S3030). After repeating this ADT packet transmission sequence, the wireless power receiving apparatus successfully transmits the last remaining fifth ADT data packet (ADT_PRx(5)) and then receives an ACK. In response, the wireless power receiving apparatus successfully transmits an EOD (S3035) and receives an ACK, thereby ending the ADT data transmission procedure.

[0266] Since not all components or steps are required for the wireless power transmission method and apparatus, or the receiving device and method according to the above-described embodiments of the present invention, the wireless power transmission device and method, or the receiving device and method may include some or all of the above-described components or steps. Furthermore, the above-described embodiments of the wireless power transmission device and method, or the receiving device and method may be combined with each other. Furthermore, the above-described components or steps do not necessarily have to be performed in the order described, and a later-described step may be performed before an earlier-described step.

[0267] The above description is merely illustrative of the technical concept of the present invention, and various modifications and variations may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the above-described embodiments of the present invention may be realized separately or in combination with each other.

[0268] Therefore, the embodiments disclosed in the present invention are for illustrative purposes only and are not intended to limit the technical idea of ​​the present invention. The scope of protection of the present invention should be interpreted by the scope of the claims, and all technical ideas within the equivalent range should be interpreted as being included in the scope of the present invention.

Claims

1. In a wireless power transmission device, a communication / control device configured to control wireless power; a power converter configured to transmit the wireless power to a wireless power receiving device; The wireless power transmission device includes: receiving a received power packet from the wireless power receiving device; transmitting a bit pattern to the wireless power receiving device during a power transmission phase in response to the received power packet, requesting permission to communicate; configured to perform a renegotiation phase with the wireless power receiving device after transmitting the bit pattern; The bit pattern is made up of 8 bits, The wireless power transmission device, wherein the bit pattern is defined as a pattern different from a bit pattern for an ACK response, a bit pattern for a NAK response, and a bit pattern for an ND response.

2. 1. A method for transmitting wireless power, the method being performed by a wireless power transmitting device, the method comprising: receiving a received power packet from a wireless power receiving device; transmitting a bit pattern to the wireless power receiving device during a power transmission phase requesting permission to communicate in response to the received power packet; and performing a renegotiation phase with the wireless power receiving device after transmitting the bit pattern; The bit pattern is made up of 8 bits, The method, wherein the bit pattern is defined as a pattern different from a bit pattern for an ACK response, a bit pattern for a NAK response, and a bit pattern for an ND response.

3. In a wireless power receiving device, a communication / control device configured to control wireless power; a power pickup unit configured to receive the wireless power from a wireless power transmission device; The wireless power receiving device includes: Transmitting a received power packet to the wireless power transmitting device; receiving a bit pattern from the wireless power transmitting device during a power transmission phase requesting permission to communicate in response to the received power packet; configured to perform a renegotiation phase with the wireless power transmitting device after receiving the bit pattern; The bit pattern is made up of 8 bits, The wireless power receiving apparatus, wherein the bit pattern is defined as a pattern different from a bit pattern for an ACK response, a bit pattern for a NAK response, and a bit pattern for an ND response.

4. 1. A method for receiving wireless power, the method being performed by a wireless power receiving device, the method comprising: transmitting the received power packet to a wireless power transmitting device; receiving a bit pattern from the wireless power transmitting device during a power transmission phase requesting permission to communicate in response to the received power packet; performing a renegotiation phase with the wireless power transmitting device after receiving the bit pattern; The bit pattern is made up of 8 bits, The method, wherein the bit pattern is defined as a pattern different from a bit pattern for an ACK response, a bit pattern for a NAK response, and a bit pattern for an ND response.

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