Method and system for adjusting power control hold-off time in wireless power transfer

Abstract

According to one aspect of the present invention, provided is a wireless power transfer method for transmitting power to a wireless power receiver using a wireless power transmitter, the method comprising the steps of: responding to receiving, from the wireless power receiver, a time adjustment (SRQ / pch) packet containing information related to a power control hold-off time adjusted by the wireless power receiver in a negotiation process with the wireless power receiver; and performing wireless power transfer to the wireless power receiver on the basis of the power control hold-off time adjusted by the wireless power receiver in response to termination of the negotiation process.

Description

Method and system for controlling power control latency in wireless power transfer

[0001] The present invention relates to a method and system for controlling power control latency in wireless power transmission.

[0002] The Wireless Power Consortium (WPC), an international standards organization for wireless power transfer, is developing the Qi standard for wireless charging. The Qi standard defines the baseline power profile (BPP) and the extended power profile (EPP), and has also defined a new magnetic power profile (MPP).

[0003] Meanwhile, the magnetic power profile described above can be driven in two wireless power transfer modes. One is a restricted mode, which allows only one-way communication from the wireless power receiver to the wireless power transmitter and transfers power at a limited power level, and the other is a full mode, which allows two-way communication between the wireless power receiver and the wireless power transmitter and has higher power levels and improved foreign object detection (FOD) capabilities. The wireless power receiver can maximize power transfer efficiency by changing the mode described above according to the current conditions.

[0004] However, in the past, when changing the above-mentioned mode, even though the detailed power transmission method or communication method was different in the two modes, the setting value including the length of the power control hold-off time was used as is without changing, which caused a problem in that the response speed in two-way communication between the wireless power receiver and the wireless power transmitter was excessively slow due to the mode change. In addition, even when supporting an extended power profile that does not support mode change, the same problem occurs because the power control hold-off time is not appropriately changed during the negotiation process.

[0005] Accordingly, the inventor(s) of the present invention propose a technology for maximizing wireless power transmission efficiency while appropriately maintaining response speed by changing the length of the power control waiting time during the negotiation process in the wireless power transmission process.

[0006] The purpose of the present invention is to solve all of the problems of the above-mentioned prior art.

[0007] In addition, the present invention has another object to prevent delay in power control by adjusting the power control waiting time during the negotiation process in response to the wireless power transmitter and wireless power receiver supporting the extended power profile (EPP).

[0008] In addition, another object of the present invention is to prevent power control from being delayed due to mode changes by adjusting a power control waiting time during a negotiation process in response to the wireless power transmitter and wireless power receiver supporting the magnetic power profile (MPP) when changing the mode of the wireless power receiver.

[0009] In addition, another object of the present invention is to maximize the efficiency of wireless power transmission by adjusting the power control waiting time during the negotiation process in wireless power transmission using a wireless power receiver and a wireless power transmitter.

[0010] A representative configuration of the present invention to achieve the above purpose is as follows.

[0011] According to one aspect of the present invention, a wireless power transmission method is provided, including a step of responding to receiving a time control (SRQ / pch) packet containing information related to a power control hold-off time adjusted by a wireless power receiver in a negotiation process with the wireless power receiver, and a step of performing wireless power transmission to the wireless power receiver based on the power control hold-off time adjusted by the wireless power receiver in response to the negotiation process being terminated.

[0012] According to another aspect of the present invention, a wireless power transmitter is provided that responds to receiving a time control (SRQ / pch) packet from a wireless power receiver containing information related to a power control hold-off time adjusted by the wireless power receiver during a negotiation process with the wireless power receiver, and performs wireless power transfer to the wireless power receiver based on the power control hold-off time adjusted by the wireless power receiver in response to the negotiation process being terminated.

[0013] According to another aspect of the present invention, a wireless power transmission method is provided, including a step of allowing a wireless power receiver to adjust a power control hold-off time during a negotiation process with a wireless power transmitter and transmit a time adjustment (SRQ / pch) packet containing information related thereto to the wireless power transmitter, and a step of requesting wireless power transmission to the wireless power transmitter based on the adjusted power control hold-off time in response to the negotiation process being terminated.

[0014] According to another aspect of the present invention, a wireless power receiver is provided that adjusts a power control hold-off time during a negotiation process with a wireless power transmitter, transmits a time adjustment (SRQ / pch) packet containing information related thereto to the wireless power transmitter, and requests wireless power transmission to the wireless power transmitter based on the adjusted power control hold-off time in response to the termination of the negotiation process.

[0015] In addition, a non-transitory computer-readable recording medium recording another method for implementing the present invention, another system, and a computer program for executing the method are further provided.

[0016] According to the present invention, in response to the wireless power transmitter and wireless power receiver supporting the extended power profile (EPP), delay in power control can be prevented by adjusting the power control waiting time during the negotiation process.

[0017] In addition, according to the present invention, in response to the wireless power transmitter and wireless power receiver supporting the magnetic power profile (MPP), when changing the mode of the wireless power receiver, the power control waiting time can be adjusted during the negotiation process to prevent power control from being delayed due to the mode change.

[0018] In addition, according to the present invention, in wireless power transmission using a wireless power receiver and a wireless power transmitter, the efficiency of wireless power transmission can be maximized by adjusting the power control waiting time during the negotiation process.

[0019] FIG. 1 is a diagram exemplarily showing several time intervals during a communication process between a wireless power receiver and a wireless power transmitter when the wireless power receiver according to one embodiment of the present invention is in a limited mode.

[0020] FIG. 2 is a diagram exemplarily showing several time intervals during a communication process between a wireless power receiver and a wireless power transmitter when the wireless power receiver according to one embodiment of the present invention is in full mode.

[0021] FIG. 3 is a diagram exemplarily showing the configuration of a time control (SRQ / pch) packet according to one embodiment of the present invention.

[0022] FIG. 4 is a diagram exemplarily showing the configuration of a negotiation start (NEGO) packet according to one embodiment of the present invention.

[0023] FIG. 5 is a diagram illustrating a time series of an example of a wireless power transmission method according to one embodiment of the present invention.

[0024] <Explanation of symbols>

[0025] Communication in 100-limit mode

[0026] Power control wait time in 110 limited mode

[0027] 120 response time

[0028] 130 Response Wait Time

[0029] 140 active hours

[0030] 150 control hours

[0031] 160 Control Error Packet

[0032] 170 Receiver Response

[0033] 180 Negotiation Start Packet

[0034] Communication in 200 full mode

[0035] 210 Power control latency in full mode

[0036] 220 response time

[0037] 230 Extended Response Wait Time

[0038] 240 active hours

[0039] 250 control hours

[0040] 260 Extended Control Error Packet

[0041] 270 Transmitter Response

[0042] 280 Amplitude Shift Keying Data Packet

[0043] 310 Request Field

[0044] 320 parameter fields

[0045] Each bit of the 400 Negotiation Start (NEGO) packet

[0046] Power transfer process in 510 limited mode

[0047] 520 Negotiation Process

[0048] 521 Negotiation Process Begins

[0049] 522 Reduction of power control latency

[0050] 523 Negotiation process ends

[0051] 530 Full mode power transfer process

[0052] The following detailed description of the present invention refers to the accompanying drawings, which illustrate specific embodiments in which the present invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present invention. It should be understood that the various embodiments of the present invention, while different from each other, are not necessarily mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be modified and implemented from one embodiment to another without departing from the spirit and scope of the present invention. Furthermore, it should be understood that the positions or arrangements of individual components within each embodiment may also be modified without departing from the spirit and scope of the present invention. Accordingly, the following detailed description is not to be taken in a limiting sense, and the scope of the present invention is to be construed to encompass the scope of the claims and all equivalents thereof. Like reference numerals in the drawings represent the same or similar elements throughout the several aspects.

[0053] Hereinafter, various preferred embodiments of the present invention will be described in detail with reference to the attached drawings so that a person having ordinary skill in the art to which the present invention pertains can easily practice the present invention.

[0054] The WPC's Qi standard defines the Baseline Power Profile (BPP) and the Extended Power Profile (EPP). The BPP is a power profile for wireless power transmitters (hereinafter, "transmitters" or "PTx") and wireless power receivers (hereinafter, "receivers" or "PRx") that support power transfer of up to 5 W, while the EPP is a power profile for wireless power transmitters and wireless power receivers that support power transfer greater than 5 W.

[0055] Meanwhile, the magnetic power profile (MPP) is a new power profile introduced in the Qi2 standard, which was first discussed based on Apple's MagSafe. Compared to the existing BPP and EPP, MPP is characterized by the addition of an additional element, namely a magnet, to ensure alignment and fixation of the transmitter (PTx) and receiver (PRx). MPP can improve power transfer efficiency by performing alignment and fixation through magnets, and is characterized by two wireless power transfer modes: restricted mode and full mode.

[0056] The limited mode according to one embodiment of the present invention may mean a power transmission mode in which one-way communication from a receiver to a transmitter is possible and the power level is limited (e.g., limited to a rectified voltage of 5 W), as one of the wireless power transmission modes of MPP.

[0057] The full mode according to one embodiment of the present invention may refer to a power transmission mode that is one of the wireless power transmission modes of MPP, which enables two-way communication between a receiver and a transmitter, and can perform wireless power transmission at a higher power level than the limited mode.

[0058] According to one embodiment of the present invention, a receiver can change its mode to full mode in response to the receiver deciding to transition during power transfer in limited mode. As described above, there are two routes for transitioning to full mode during power transfer in limited mode. The first route is a "transition with power interruption" route, in which the receiver transmits a packet requesting the transmitter to remove the power signal, the transmitter receiving this stops power transmission, returns to the initial stage of power transmission (ping stage), and then changes the mode. The second route is a "transition without power interruption" route, in which the transmitter continuously transmits a "signal to check whether a mode change is possible (or, MPP FSK pattern)" to the receiver in response to the transmitter receiving a control error (CE) packet that the receiver continuously transmits during the power transfer process, and the receiver receives, decodes, and responds to the signal described above, thereby changing the mode without interrupting the power transfer. The mode change according to one embodiment of the present invention is not limited to either of the two routes described above and may be performed through both routes, but may primarily mean a mode change performed according to the "power-interruption-free conversion" route described above.

[0059] Meanwhile, the receiver may undergo a negotiation process to change its mode from limited mode to full mode. This specification focuses on the negotiation process and power transfer process to explain the adjustment of power control waiting time during the negotiation process according to one embodiment of the present invention. However, the processes that the receiver and transmitter may undergo to perform wireless power transfer are not limited to the aforementioned negotiation process, and various other processes may be included in wireless power transfer.

[0060] A receiver and a transmitter according to one embodiment of the present invention can appropriately adjust a power control waiting time during a negotiation process to prevent occurrence of power control delay and deterioration of wireless power transmission efficiency due to a change in mode.

[0061] Below, before describing a receiver and a transmitter according to one embodiment of the present invention, the power transmission process and its time interval in limited mode and full mode will first be described to aid understanding.

[0062] Meanwhile, the description below will focus on the case where the receiver and transmitter support MPP and thus the mode can be changed during the negotiation process to help understanding. However, even in the case where the receiver and transmitter according to an embodiment of the present invention support EPP (i.e., do not support mode change through the negotiation process), the power control waiting time can be appropriately adjusted during the negotiation process based on the description below, and power transmission can be performed in an optimal manner accordingly. That is, the description below focuses on the case where the mode is changed during the negotiation process in response to the receiver and transmitter supporting MPP. It should be noted that, for the case where the receiver and transmitter support EPP, it can be understood that the power control waiting time can be adjusted in a similar manner through a negotiation process that does not change the mode, excluding the description related to mode change in the description below.

[0063] <Power transfer process and time interval in limited mode>

[0064] FIG. 1 illustrates communication in a limited mode (or power transmission in a limited mode) and each time interval (100). Referring to FIG. 1, a receiver and a transmitter according to an embodiment of the present invention can control power during a power transmission process by communicating based on a power control waiting time (110) defined in the limited mode. Specifically, during the power transmission process, the receiver periodically transmits a control error (CE) packet (160) to the transmitter, and the transmitter responds to this and can control power based on this.

[0065] Meanwhile, the power control waiting time (110) or delay time (t) in the limited mode delay ) can be defined as the time from the time (111) when the receiver receives a control error packet (160) from the transmitter to the time before power control starts (112). The power control waiting time (110) described above may mean a surplus time for stabilizing the coil current after communication. In summary, the power control waiting time in the limited mode according to one embodiment of the present invention may be the time from the time the transmitter receives a control error (CE) packet from the receiver (or the time the receiver transmits a control error packet to the transmitter) (111) to the time immediately before power control starts (112).

[0066] If you continue, the response time (120)(t response) may refer to the time until a transmitter that has received a control error packet (160) responds (e.g., an MPP response (170) in FIG. 1), and a response waiting time (130) (tresponsetimeout) refers to the maximum time that a transmitter that has received a control error packet can respond appropriately. If the response waiting time (130) is exceeded, even if the transmitter responds, it may be treated as an inappropriate response.

[0067] If you continue, the active time (140)(t active ) may mean a time interval during which a receiver that has received a control error packet (160) from a transmitter actually controls power, and the control time (150) (t control ) is a time interval starting from the end of the power control waiting time (110), and may mean a free time until the next packet can be transmitted. The above-described control time (150) may start from the same time and last longer than the active time (140), and the receiver may transmit the next packet after the above-described power control waiting time (110) and control time (150) have exceeded after transmitting the control error packet. Here, the next packet may be, for example, a negotiation start (NEGO) packet (180).

[0068] <Power transfer process and time interval in full mode>

[0069] Next, Fig. 2 shows communication in full mode (or power transmission in full mode) and each time interval (200). Referring to Fig. 2, a receiver and a transmitter according to an embodiment of the present invention can control power during a power transmission process by communicating based on a power control waiting time (210) defined in full mode. Specifically, during the power transmission process, the receiver periodically transmits an extended control error (XCE) packet (260) to the transmitter, and the transmitter responds to this and can control power based on this.

[0070] Meanwhile, the power control waiting time (210) or delay time (t) in full mode delay ) can be defined as the time from the time when the extended response waiting time (230) (txce_responsetimeout) that starts from the time when the receiver receives the extended control error packet (260) from the transmitter ends (211) to before the power control starts (i.e., before the start of the active time (240) to be described later) (212). In summary, the power control waiting time in the full mode according to one embodiment of the present invention can be the time from the time when the extended response waiting time (230) that starts from the time when the extended control error packet is received from the receiver described above ends (211) to the time immediately before the power control starts (212).

[0071] The power control waiting time (210) described above may refer to a surplus time that allows for the coil current to stabilize after communication. In other words, the power control waiting time (210) in full mode may refer to a time interval that has the same purpose as the power control waiting time (110) in limited mode, but differs only in the definition of the point in time at which the interval begins.

[0072] If you continue, the response time (220)(t response ) may refer to the time until the transmitter that received the extended control error packet (260) responds (270) (e.g., pattern response in FIG. 2), and the extended response waiting time (230) (txce_responsetimeout) refers to the maximum time that the transmitter that received the extended control error packet can respond appropriately. If the extended response waiting time (230) is exceeded, even if the transmitter responds, it may be treated as an inappropriate response.

[0073] If you continue, the active time (240)(t active ) and control time (250)(t control) are identical to the active time (140) and the control time (150) defined in the above-described limited mode, respectively. In conclusion, after the receiver transmits the extended control error packet, the extended response waiting time (230), the power control waiting time (210), and the control time (250) must all exceed before transmitting the next packet. Here, the next packet may be, for example, an amplitude shift keying (ASK) data packet (280).

[0074] <Data Packet>

[0075] The receiver or transmitter of the present invention can communicate by transmitting packets to each other. A packet (or data packet) according to one embodiment of the present invention may include fields divided into bytes (B) and bits (b) as structured information units.

[0076] Meanwhile, the meaning of a receiver or transmitter according to an embodiment of the present invention receiving a packet and responding thereto may mean transmitting the above-described data packet as a response or transmitting a simple response signal (e.g., an FSK or ASK signal to be described later) rather than a packet.

[0077] Below, a wireless power transmission method according to one embodiment of the present invention will be described in detail based on the characteristics of the above-described receiver and transmitter.

[0078] Wireless power transmission method according to the present invention

[0079] In the existing Qi standard specifications, when changing the receiver mode, the numerical value (e.g., power control latency) used in the previous limited mode is not changed and is used as is in all modes. However, in the existing Qi standard specifications, even if the power control latency is of an appropriate length for application to the limited mode, it is too long to be applied as is in all modes, which causes a problem that interferes with communication between the receiver and transmitter and efficient wireless power transfer.

[0080] However, in the wireless power transmission method according to the present invention, unlike the wireless power transmission method defined in the specifications of the existing Qi standard, by adjusting the related numerical value (i.e., the length of the power control waiting time) in advance during the negotiation process that can change the mode of the receiver, even if the mode of the receiver is changed, communication delay (e.g., delayed response to an extended control error packet, etc.) does not occur, and wireless power transmission can be performed with high efficiency through rapid power control.

[0081] Hereinafter, in a method for performing wireless power transfer from a transmitter to a receiver according to the present invention, a transmitter, a receiver, and their operations when a mode change of the receiver is involved will be described in detail.

[0082] <Operation of a wireless power transmitter>

[0083] First, a transmitter according to one embodiment of the present invention may respond to receiving a time adjustment (SRQ / pch) packet from a receiver containing information related to a power control hold-off time adjusted by the receiver in a negotiation process that may change the mode of the receiver.

[0084] The negotiation process according to one embodiment of the present invention may refer to a process that can change a mode and power transfer contract as a step included in the wireless power transfer process. Specifically, the above-described power transfer contract change may utilize a question and answer approach. The above-described question and answer approach may refer to a method in which a receiver transmits a simple query data packet to a transmitter, and the transmitter responds to it. For example, the receiver may ask the transmitter whether it supports a specific power level, and the receiver may respond with an affirmative (ACK) or negative (NAK) response to negotiate a change to the power transfer contract.

[0085] Continuing, the transmitter and receiver according to one embodiment of the present invention can change the mode of the receiver along with modifying the power transfer contract during the negotiation process.

[0086] A time adjustment (SRQ / pch) packet according to one embodiment of the present invention may mean a packet that a receiver transmits to a transmitter during a negotiation process in response to the receiver attempting to adjust a power control waiting time.

[0087] Meanwhile, during the negotiation process, a plurality of negotiable elements included in the power transfer contract can be changed. The plurality of negotiable elements described above include a power control waiting time, and the receiver can transmit the above-described time adjustment (SRQ / pch) packet to the transmitter in order to negotiate a change in the power control waiting time with the transmitter. Specifically, when the receiver changes the power control waiting time, it can include the change in the power control waiting time in the above-described time adjustment (SRQ / pch) packet and transmit it to the transmitter, and the transmitter that receives the time adjustment packet can appropriately acknowledge the change in the power control waiting time by responding (e.g., ACK) to acknowledge the change. That is, the transmitter and receiver according to one embodiment of the present invention can change the power control waiting time, which is at least one of the plurality of negotiable elements included in the power transfer contract, and change the mode during the negotiation process.

[0088] The response of the above-described transmitter may be, for example, a response pattern that acknowledges (ACK) a change in the power control wait time or that rejects (NAK) a change in the power control wait time. Meanwhile, the response of the above-described transmitter may be transmitted at an operating frequency of, for example, 360 kHz.

[0089] Specifically, the above-described negotiation process may be initiated in response to the transmitter responding by receiving a Negotiation Initiation (NEGO) packet containing information related to the start of the negotiation process from the receiver.

[0090] A negotiation start (NEGO) packet according to one embodiment of the present invention may mean a packet transmitted to a transmitter by a receiver to start a negotiation process that can change a mode from a limited mode to a full mode or change a power transmission contract.

[0091] Meanwhile, the transmitter that receives the aforementioned Negotiation Initiation (NEGO) packet can respond to it, and through the response, can acknowledge (ACK) the start of the negotiation process or request (ATN) additional communication. However, the transmitter cannot respond with a non-acknowledgement (NAK or ND) to the Negotiation Initiation packet, and if the transmitter responds with such a response, the receiver can ignore the response and continue the current process (e.g., power transfer process) as is.

[0092] Here, the above-described Negotiation Initiation (NEGO) packet can be transmitted from the receiver to the transmitter in response to the receiver receiving and decoding a signal from the transmitter to determine whether a mode change is possible.

[0093] According to one embodiment of the present invention, after receiving a control error packet from a receiver in a limited mode, a transmitter can continuously transmit a signal to the receiver to determine whether a change in mode is possible during a power control waiting time.

[0094] Meanwhile, the signal for checking whether the above-described mode change is possible may include information that the above-described transmitter supports MPP wireless power transmission or mode change, and accordingly, the above-described "signal for checking whether the mode change is possible" may also be expressed as "a signal notifying that it is a transmitter that supports mode change."

[0095] That is, a negotiation start (NEGO) packet transmitted by a receiver to a transmitter according to one embodiment of the present invention can be transmitted to the transmitter in response to the receiver receiving and decoding a signal indicating that the transmitter supports mode change at a time when the receiver wants to switch to full mode.

[0096] Meanwhile, the point in time when the receiver described above wishes to switch to full mode may mean a point in time when the receiver is unable to perform decoding and then becomes capable again. Specifically, when the receiver is unable to decode a signal indicating that the transmitter supports mode change (for example, when the receiver's battery is low or discharged and only supports minimal functions, making decoding impossible), the receiver may request power transfer in limited mode, and then, when decoding becomes possible later, may wish to switch to full mode, and may transmit a negotiation start (NEGO) packet to the transmitter to switch to full mode.

[0097] In summary, (1) the transmitter transmits a signal to the receiver to determine whether a mode change is possible, (2) the receiver receives the signal and decodes it, (3) in response to successful decoding, the receiver transmits a negotiation start (NEGO) packet to the transmitter, and (4) the negotiation process can be initiated in response to the transmitter receiving the negotiation start (NEGO) packet and sending an ACK response. By changing the mode through the negotiation process initiated through the above-described processes (1) to (4), the mode change can be performed without interrupting power transmission (i.e., without power transmission being cut off).

[0098] Meanwhile, the signal that determines whether a mode change is possible may be, for example, a frequency shift keying (FSK) pattern, specifically "1000 1000".

[0099] Meanwhile, according to one embodiment of the present invention, decoding a signal from a transmitter by a receiver may mean interpreting the signal from the transmitter to extract meaningful information. Specifically, this may mean reconstructing the modulated signal transmitted by the transmitter to obtain the original information, thereby identifying an ACK, NAK, or other response.

[0100] Meanwhile, Fig. 4 is a diagram exemplarily illustrating the configuration of a Negotiation Start (NEGO) packet according to one embodiment of the present invention. Referring to Fig. 4, the receiver can set the reserved bits among each bit (b0 to b7) (400) of the Negotiation Start (NEGO) packet to "ZERO," and the transmitter can ignore all reserved bits.

[0101] Specifically, information related to the power control latency adjusted by the receiver may include information related to shortening the power control latency.

[0102] Information related to shortening the power control wait time according to one embodiment of the present invention may mean resetting the power control wait time to a relatively short time compared to the power control wait time in the limited mode. Meanwhile, the power control wait time according to one embodiment of the present invention may have a value of 5 ms or more and 100 ms or less.

[0103] Continuing, as described above, shortening the power control waiting time may mean that, for example, in response to the power control waiting time being 50 ms in the limited mode, the receiver shortens the power control waiting time to 5 ms during the negotiation process, and includes information about the shortened power control waiting time in the parameter part of the time adjustment (SRQ / pch) packet and transmits it to the transmitter. However, the above-described power control waiting time adjustment process and the numerical value of the power control waiting time are merely examples, and are not limited thereto, and all cases in which the power control waiting time is relatively shortened in the full mode compared to the limited mode are included in the adjustment of the power control waiting time according to an embodiment of the present invention.

[0104] Specifically, the above-described time control (SRQ / pch) packet may include a packet for a specific request (SRQ), and the packet for the specific request may include a request field and a parameter field, and a value for a power control waiting time request may be recorded in the request field, and a delay time value may be recorded in the parameter field.

[0105] A packet for specific request transmission (SRQ) according to one embodiment of the present invention is a type of data packet that a receiver can transmit, and may mean a data packet that includes content that a transmitter wishes to request.

[0106] Referring to FIG. 3, a packet for transmitting a specific request may include a request field (310) including eight bits indicated by b0 to b7 and including a byte indicated by B0, and a parameter field (320) including eight bits indicated by b0 to b7 and including a byte indicated by B1.

[0107] Continuing, the above-described request field is a field in which a value that distinguishes what is being requested is recorded, and in the case of a time control (SRQ / pch) packet, a character may be recorded to indicate that it is a packet requesting a change in power control waiting time, and for example, the above-described character may be 0x07.

[0108] Next, the parameter field described above may refer to a field in which the numerical value of the actual adjusted power regulation wait time (i.e., the length of the power regulation wait time after the change) is recorded. Specifically, the power regulation wait time described in the parameter field described above may be a value obtained by dividing the power regulation wait time by 1 ms and removing the unit.

[0109] For example, if the receiver wants to change the power regulation wait time from 50 ms to 5 ms, the parameter field described above can be represented by bits b0 through b7 with the value "5 (i.e., 5 ms divided by 1 ms)".

[0110] Next, a transmitter according to one embodiment of the present invention can perform wireless power transfer to a receiver based on a power control waiting time adjusted by the receiver in response to the termination of the negotiation process and the change in the mode of the receiver.

[0111] Here, the mode of the receiver according to one embodiment of the present invention can be changed from a limited mode to a full mode through a negotiation process.

[0112] That is, the receiver according to one embodiment of the present invention can change the mode through a negotiation process, and since the power control waiting time is adjusted during the negotiation process, the power control waiting time in the full mode after the negotiation process becomes relatively shorter than the power control waiting time in the limited mode before the negotiation process. As described above, in the limited mode, the power control waiting time is calculated from the time the transmitter receives the control error packet, but in the full mode, the power control waiting time is calculated from the time the extended response waiting time described above ends. Therefore, if the long power control waiting time used in the limited mode is used as is in the full mode, the response time for the extended control error packet may become excessively long, which may delay power control and cause a problem in that power transmission is not performed smoothly. Therefore, by adjusting the power control waiting time in response to changing the mode through a negotiation process as in one embodiment of the present invention, the occurrence of the above-described problem can be prevented.

[0113] If continued, the above-described negotiation process may be terminated in response to the transmitter receiving and responding to a negotiation termination (SRQ / en) packet containing information regarding the termination of the negotiation process from the receiver.

[0114] A negotiation termination (SRQ / en) packet according to one embodiment of the present invention is a type of data packet that a receiver can transmit, and may mean a data packet that includes content requesting the transmitter to terminate the negotiation process.

[0115] Here, the above-described negotiation termination (SRQ / en) packet includes a packet for specific request transmission (SRQ), and the packet for the specific request transmission includes a request field and a parameter field, and a value for termination of the negotiation process can be recorded in the request field, and the number of elements of a power transfer contract changed in the negotiation process can be recorded in the parameter field.

[0116] The meaning of specific request transmissions, request fields and parameters related to the above-described negotiation termination (SRQ / en) packet has already been described in detail in relation to the negotiation start packet, so description thereof is omitted to avoid excessive duplication.

[0117] The value for termination of the negotiation process recorded in the request field of the negotiation termination packet according to one embodiment of the present invention may mean a character for indicating that it is a packet for termination of the negotiation process, and may be, for example, 0x00.

[0118] The number of elements of a power transmission contract changed during a negotiation process recorded in a parameter field of a negotiation termination packet according to one embodiment of the present invention may mean the number of elements of a power transmission contract whose values ​​have been changed through a negotiation process.

[0119] According to one embodiment of the present invention, a transmitter may respond to a receiver upon receiving the aforementioned negotiation completion (SRQ / en) packet from the receiver. Specifically, the aforementioned response may include an acknowledgement pattern (ACK) indicating that the negotiation process has successfully completed, and a acknowledgement pattern (NAK) indicating that the negotiation process was unsuccessful, discarding all changes and restarting the negotiation process based on the power transfer agreement prior to the change.

[0120] In summary, the mode of the receiver may be changed in response to one or more negotiation conditions being met and the negotiation being terminated during the above-described negotiation process.

[0121] Here, the negotiation conditions may include at least one of a plurality of elements included in a power transfer contract.

[0122] A power transmission contract according to one embodiment of the present invention may mean provisions for settings and numerical values ​​in the power transmission stage.

[0123] The provisions for the settings and numerical values ​​in the power transmission stage described above may be of multiple types, and therefore, they may be expressed as "multiple elements included in the power transmission contract." These multiple elements include, for example, reference power, received power measurement time (t window ), received power measurement offset (t offset ), power control waiting time (t delay ), received power reporting resolution, FSK polarity, modulation depth, number of cycles per bit, potential load power, guaranteed load power, and re-ping delay (t reping ) may be included.

[0124] Next, in a step of performing wireless power transmission according to one embodiment of the present invention, a transmitter according to one embodiment of the present invention can respond to an extended control error packet received from a receiver based on a power control waiting time adjusted by the receiver.

[0125] Responding to an extended control error packet received from a receiver based on the adjusted power control waiting time as described above may mean that, when performing power transfer in the changed full mode after the negotiation process, communication and power transfer using the extended control error packet are performed with the power control waiting time adjusted to a short state.

[0126] Wireless Power Transmitter

[0127] A transmitter according to one embodiment of the present invention may be a device that responds to receiving a time control (SRQ / pch) packet from a receiver containing information related to a power control hold-off time adjusted by the receiver during a negotiation process capable of changing a mode of the receiver or a negotiation process with a wireless power receiver, and performs wireless power transfer to the receiver based on the power control hold-off time adjusted by the receiver in response to the negotiation process being terminated and the mode of the receiver being changed (or in response to the negotiation process being terminated).

[0128] <Operation of the wireless power receiver>

[0129] The operation of the receiver described below is identical to the operation of the transmitter described above, described from the receiver's perspective. It is to be noted in advance that even if there is no special mention of the same, it is identical to the description of the transmitter described above.

[0130] A receiver according to one embodiment of the present invention can adjust a power control waiting time during a negotiation process for changing a mode and transmit a time adjustment (SRQ / pch) packet containing information related thereto to a transmitter.

[0131] Here, the structure and characteristics of the above-described negotiation termination (SRQ / pch) packet have already been described in detail in the above “Operation of the wireless power transmitter”, so description thereof is omitted to avoid excessive duplication.

[0132] Specifically, the above-described negotiation process can be initiated in response to the receiver transmitting a Negotiation Start (NEGO) packet containing information related to the start of the negotiation process to the transmitter and receiving a response from the transmitter.

[0133] Here, the receiver may transmit a negotiation start (NEGO) packet to the transmitter in response to receiving and decoding a signal indicating that the transmitter supports mode change from the transmitter.

[0134] Specifically, a receiver according to one embodiment of the present invention can be adjusted by shortening a power control waiting time.

[0135] Next, the receiver according to one embodiment of the present invention can request wireless power transfer to the transmitter based on the adjusted power control waiting time in response to the termination of the negotiation process and the change of mode.

[0136] According to one embodiment of the present invention, a request by a receiver to a transmitter for wireless power transfer may mean that the receiver performs a power transfer process including continuously transmitting extended control error packets to the transmitter during the power transfer process and approving or rejecting updating power (voltage) based on the extended control error packets received by the transmitter.

[0137] Here, a receiver according to one embodiment of the present invention can change the mode from a restricted mode to a full mode through a negotiation process.

[0138] Specifically, the above-described negotiation process can be terminated in response to the receiver transmitting a negotiation termination (SRQ / en) packet containing information regarding the termination of the negotiation process to the transmitter, and the transmitter responding thereto.

[0139] Here, the structure and characteristics of the above-described negotiation termination (SRQ / en) packet have already been described in detail in the above “Operation of the wireless power transmitter”, so description thereof is omitted to avoid excessive duplication.

[0140] Specifically, the receiver described above may change modes in response to one or more negotiation conditions being met and the negotiation being terminated during the negotiation process described above.

[0141] Here, the negotiation conditions may include at least one of the multiple elements included in the power transfer contract. The negotiation conditions, power transfer contract, and multiple elements included in the power transfer contract have already been described in detail in the section "Operation of the Wireless Power Transmitter" above, and therefore, further description thereof is omitted to avoid excessive duplication.

[0142] Next, in a step in which a receiver according to one embodiment of the present invention requests wireless power transmission to a transmitter, the receiver may transmit an extended control error packet to the transmitter based on the power control waiting time adjusted above.

[0143] Transmitting an extended control error packet based on the power control waiting time adjusted by the above-described receiver may mean that when performing power transmission in the changed full mode after the negotiation process, communication and power transmission based on the extended control error packet are performed with the power control waiting time adjusted to a short state.

[0144] Wireless Power Receiver

[0145] A receiver according to one embodiment of the present invention may be a device that adjusts a power control hold-off time during a negotiation process in which a wireless power receiver can change a mode or a negotiation process with a wireless power transmitter, transmits a time adjustment (SRQ / pch) packet containing information related thereto to the wireless power transmitter, and requests wireless power transmission to the wireless power transmitter based on the adjusted power control hold-off time in response to the termination of the negotiation process and the change of mode (or in response to the termination of the negotiation process).

[0146] Wireless power transfer embodiment

[0147] Below, an example of a method for controlling a power control wait time during a wireless power transfer process using a transmitter and a receiver according to an embodiment of the present invention is described. Meanwhile, the process described below is merely an example of a method for performing wireless power transfer using a transmitter and a receiver according to an embodiment of the present invention, and it is obvious to those skilled in the art that the transmitter and receiver according to an embodiment of the present invention are not limited thereto and can perform wireless power transfer through various processes that are consistent with the purpose of the present invention.

[0148] Referring to FIG. 5, wireless power transmission according to one embodiment of the present invention is broadly divided into three stages. The three stages may be (1) a power transmission process in a limited mode (510), (2) a negotiation process (520), and (3) a power transmission process in a full mode (530). The above-described processes (1) to (3) may be arranged in chronological order.

[0149] First, the power transfer process (510) in the limited mode may be a process in which one-way communication is performed and wireless power transfer is performed with limited power. In this step, the receiver continuously transmits control error (CE) packets to the transmitter, and the transmitter may continuously transmit a signal ("MPP" in 510 of FIG. 5) notifying the receiver that it is a transmitter that supports mode changes. Meanwhile, the power control waiting time in the power transfer process (510) in the limited mode may be 50 ms.

[0150] Next, the receiver may initiate a negotiation process (520) by sending a negotiation start (NEGO) packet to the transmitter at a point in time when the receiver wants to switch from limited mode to full mode, and the transmitter may receive this and send an FSK response (ACK) back to the receiver (521).

[0151] Meanwhile, in the above-described negotiation process, negotiation may be conducted through packets such as ECAP, which is a packet that transmits information on the power reception capability of the receiver, and PLAP packet, which transmits information on power transmission loss. In particular, the receiver according to one embodiment of the present invention may shorten the power control waiting time through a process of transmitting a time adjustment (SRQ / pch) packet to the transmitter and receiving an FSK response from the transmitter in the above-described negotiation process (522). For example, the power control waiting time may be shortened from the existing 50 ms to 5 ms through the above-described time adjustment (SRQ / pch) packet. That is, the power control waiting time in the power transmission process (510) in the limited mode may be 50 ms, and after the negotiation process, the power control waiting time in the power transmission process (530) in the full mode may be 5 ms.

[0152] Next, the negotiation process (520) may be terminated when the receiver transmits a negotiation termination (SRQ / en) packet to the transmitter, and the transmitter retransmits an FSK response (ACK) (523).

[0153] Next, in response to the termination of the negotiation process, a full-mode power transfer process (530) may be initiated. In the full-mode power transfer process, the receiver may continuously transmit extended control error packets (XCE) to the transmitter, while maintaining an appropriate level of power, allowing wireless power transfer to proceed. In the full-mode power transfer process (530), a shortened power transfer control time (i.e., 5 ms) may be applied to perform power transfer.

[0154] To reiterate, while the explanation so far has used transmitters and receivers supporting MPP as examples, it should be made clear that this technology can also be used with transmitters and receivers supporting EPP. That is, if an EPP receiver needs to adjust the power control latency to improve power transfer efficiency, it can do so using SRQ / pch packets during the negotiation process, as described above.

[0155] Specifically, the power control latency in transmitters and receivers supporting MPP can be adjusted through a negotiation process that can change modes, and even in the case of EPP without a mode change function, the power control latency can be adjusted through a general (i.e., unrelated to mode change) negotiation process.

[0156] Although the present invention has been described above with specific details such as specific components and limited examples and drawings, these are provided only to help a more general understanding of the present invention, and the present invention is not limited to the above examples, and those with ordinary knowledge in the technical field to which the present invention pertains can make various modifications and changes based on this description.

[0157] Therefore, the idea of ​​the present invention should not be limited to the embodiments described above, and not only the scope of the patent claims described below but also all scopes equivalent to or equivalently modified from the scope of the patent claims are considered to fall within the scope of the idea of ​​the present invention.

Claims

1. A wireless power transmission method for transmitting power to a wireless power receiver using a wireless power transmitter, A step of responding to receiving a time control (SRQ / pch) packet containing information related to a power control hold-off time adjusted by the wireless power receiver in a negotiation process with the wireless power receiver, and In response to the termination of the above negotiation process, a step of performing wireless power transfer to the wireless power receiver based on a power control waiting time adjusted by the wireless power receiver is included. Method for wireless power transfer.

2. In paragraph 1, In response to the wireless power transmitter and wireless power receiver supporting the magnetic power profile (MPP), the mode of the wireless power receiver is changed through the negotiation process. Method for wireless power transfer.

3. In paragraph 2, The mode of the above wireless power receiver is changed from restricted mode to full mode through a negotiation process. Method for wireless power transfer.

4. In paragraph 1, The above negotiation process starts in response to the wireless power transmitter receiving and responding with a Negotiation Initiation (NEGO) packet containing information related to the start of the negotiation process from the wireless power receiver. Method for wireless power transfer.

5. In paragraph 4, The above Negotiation Start (NEGO) packet is transmitted from the wireless power receiver to the wireless power transmitter in response to the wireless power receiver receiving and decoding a signal indicating that the transmitter supports mode change from the wireless power transmitter. Method for wireless power transfer.

6. In paragraph 1, Information related to the power control latency controlled by the wireless power receiver includes information related to shortening the power control latency. Method for wireless power transfer.

7. In paragraph 1, The above time control (SRQ / pch) packet contains a packet for specific request transmission (specific request, SRQ), The packet for transmitting the above specific request includes a request field and a parameter field. The above request field records a value for the power control waiting time request, and the above parameter field records a delay time value. Method for wireless power transfer.

8. In paragraph 1, The above negotiation process is terminated in response to receiving a negotiation termination (SRQ / en) packet containing information about the termination of the negotiation process from the wireless power receiver and responding to it. Method for wireless power transfer.

9. In paragraph 8, The above negotiation termination (SRQ / en) packet contains a packet for specific request transmission (specific request, SRQ). The packet for transmitting the above specific request includes a request field and a parameter field. The above request field contains a value for the termination of the negotiation process, and the parameter field contains the number of elements of the power transfer contract that were changed during the negotiation process. Method for wireless power transfer.

10. In paragraph 2, In the above negotiation process, the mode of the wireless power receiver is changed in response to one or more negotiation conditions being met and the negotiation being terminated. Method for wireless power transfer.

11. In paragraph 10, The above negotiation conditions include at least one of the multiple elements included in the power transfer contract. Method for wireless power transfer.

12. In paragraph 3, In the above-mentioned limited mode, the power control waiting time is the time from the time a control error (CE) packet is received from the wireless power receiver until power control starts. In the above full mode, the power control waiting time is the time from the time when the extended response waiting time starts to the time when the extended control error (XCE) packet is received from the wireless power receiver until the power control starts. Method for wireless power transfer.

13. In paragraph 1, In the step of performing the wireless power transmission, responding to an extended control error packet received from the wireless power receiver based on the power control waiting time adjusted by the wireless power receiver. Method for wireless power transfer.

14. As a wireless power transmitter, In response to receiving a time control (SRQ / pch) packet containing information related to a power control hold-off time adjusted by the wireless power receiver during a negotiation process with the wireless power receiver, responding to the reception of the time control (SRQ / pch) packet from the wireless power receiver, and performing wireless power transfer to the wireless power receiver based on the power control hold-off time adjusted by the wireless power receiver in response to the termination of the negotiation process. Wireless power transmitter.

15. A wireless power transmission method for transmitting power to a wireless power receiver using a wireless power transmitter, A step in which a wireless power receiver adjusts a power control hold-off time during a negotiation process with a wireless power transmitter and transmits a time adjustment (SRQ / pch) packet containing information related thereto to the wireless power transmitter, and In response to the termination of the above negotiation process, a step of requesting wireless power transfer to the wireless power transmitter based on the adjusted power control waiting time is included. Method for wireless power transfer.

16. In paragraph 15, In response to the wireless power transmitter and wireless power receiver supporting the magnetic power profile (MPP), the mode of the wireless power receiver is changed through the negotiation process. Method for wireless power transfer.

17. In paragraph 16, The above wireless power receiver changes the mode from restricted mode to full mode through a negotiation process. Method for wireless power transfer.

18. In paragraph 15, The above negotiation process starts in response to the wireless power receiver transmitting a negotiation start (NEGO) packet containing information related to the start of the negotiation process to the wireless power transmitter and receiving a response from the wireless power transmitter. Method for wireless power transfer.

19. In Article 18, The wireless power receiver receives a signal from the wireless power transmitter indicating that the transmitter supports mode change, and in response to decoding the signal, transmits the negotiation start (NEGO) packet to the wireless power transmitter. Method for wireless power transfer.

20. In paragraph 15, The above wireless power receiver is controlled by reducing the power control waiting time. Method for wireless power transfer.

21. In paragraph 15, The above time control (SRQ / pch) packet contains a packet for specific request transmission (specific request, SRQ), The packet for transmitting the above specific request includes a request field and a parameter field. The above request field records a value for the power control waiting time request, and the above parameter field records a delay time value. Method for wireless power transfer.

22. In paragraph 15, The above negotiation process ends when the wireless power receiver transmits a negotiation termination (SRQ / en) packet containing information about the termination of the negotiation process to the wireless power transmitter, and the wireless transmission transmitter responds to it. Method for wireless power transfer.

23. In paragraph 22, The above negotiation termination (SRQ / en) packet contains a packet for specific request transmission (specific request, SRQ). The packet for transmitting the above specific request includes a request field and a parameter field. The above request field contains a value for the termination of the negotiation process, and the parameter field contains the number of elements of the power transfer contract that were changed during the negotiation process. Method for wireless power transfer.

24. In paragraph 16, In response to one or more negotiation conditions being met and the negotiation being terminated during the above negotiation process, the wireless power receiver changes the mode. Method for wireless power transfer.

25. In paragraph 24, The above negotiation conditions include at least one of the multiple elements included in the power transfer contract. Method for wireless power transfer.

26. In paragraph 17, In the above-mentioned limited mode, the power control waiting time is the time from the time when the wireless power transmitter receives the control error (CE) packet transmitted by the wireless power receiver until the power control starts. In the above full mode, the power control waiting time is the time from the time the extended response waiting time starts when the wireless power transmitter receives the extended control error (XCE) packet transmitted by the wireless power receiver until the power control starts. Method for wireless power transfer.

27. In paragraph 15, In the step of requesting the wireless power transmission, an extended control error packet is transmitted to the wireless power transmitter based on the adjusted power control waiting time. Method for wireless power transfer.

28. As a wireless power receiver, In a negotiation process with a wireless power transmitter, a power control hold-off time is adjusted, a time adjustment (SRQ / pch) packet containing information related thereto is transmitted to the wireless power transmitter, and in response to the termination of the negotiation process, a wireless power transmission is requested to the wireless power transmitter based on the adjusted power control hold-off time. Wireless power receiver.

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