Power transmission equipment, power receiving equipment, methods performed by power transmission equipment, methods performed by power receiving equipment, and programs

Abstract

This invention provides a technology for appropriately determining the state between power transmission equipment and power receiving equipment. [Solution] A power transmission device according to one aspect of the present disclosure is a power transmission device that wirelessly transmits power to a power receiving device, and is characterized by comprising: a power transmission coil; an enclosure enclosing the power transmission coil; a transmitting means for transmitting first information relating to the distance between the power transmission coil and the enclosure to the power receiving device; a receiving means for receiving second information corresponding to the first information from the power receiving device; and a determining means for determining the coupling state based on the second information.

Description

[Technical Field]

[0001] This disclosure relates to power transmission equipment, power receiving equipment, methods performed by power transmission equipment, methods performed by power receiving equipment, and programs. [Background technology]

[0002] Patent Document 1 discloses a power transmission device that improves the accuracy of detecting metallic foreign objects by detecting the state of electromagnetic coupling with the secondary coil based on a correction value, thereby suppressing the influence of the metal casing of a portable device or the like, which is the receiving side (secondary side). Hereinafter, the state of electromagnetic coupling will also be referred to as the electromagnetic coupling state or simply the coupling state. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2012-244732 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The coupling state between the power transmission device and the power reception device is affected by the distance between the power transmission coil and the power reception coil. Therefore, in the conventional technology described above, if the coefficient (correction value) used to detect or determine the coupling state between the power transmission device and the power reception device is not determined based on the distance between the power transmission coil and the power reception coil, it may not be possible to properly determine the coupling state. As a result, it may become impossible to properly detect metallic foreign objects, and wireless power transmission from the power transmission device to the power reception device may not be performed properly.

[0005] One aspect of this disclosure, in view of the above, aims to provide a technology for appropriately determining the state between a power transmission device and a power receiving device. [Means for solving the problem]

[0006] A power transmission device according to one aspect of the present disclosure is a power transmission device that wirelessly transmits power to a power receiving device, and is characterized by comprising: a power transmission coil; an enclosure enclosing the power transmission coil; a transmitting means for transmitting first information relating to the distance between the power transmission coil and the enclosure to the power receiving device; a receiving means for receiving second information corresponding to the first information from the power receiving device; and a determining means for determining the coupling state based on the second information. [Effects of the Invention]

[0007] According to one aspect of this disclosure, the state between the power transmission device and the power receiving device can be appropriately determined. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows an example configuration of a wireless power transmission system according to the first embodiment. [Figure 2] This is a functional block diagram showing an example configuration of a power transmission device according to the first embodiment. [Figure 3] This is a functional block diagram showing an example configuration of a power receiving device according to the first embodiment. [Figure 4] This diagram illustrates the threshold setting method for state detection using the Power Loss method. [Figure 5] This is a diagram explaining the Q-value measurement method. [Figure 6] This is a block diagram showing an example of the functional configuration of the control unit of a power transmission device according to the first embodiment. [Figure 7] This flowchart shows an example of processing in a power transmission device. [Figure 8] This is a flowchart showing an example of processing by a power receiving device. [Figure 9] This diagram illustrates the distance between the antenna (coil) and the enclosure. [Figure 10] This flowchart shows an example of processing by a power transmission device according to the first embodiment. [Figure 11] This is a flowchart showing an example of processing by a power receiving device according to the first embodiment. [Figure 12]This flowchart shows an example of processing by a power transmission device according to the second embodiment. [Figure 13] This is a flowchart showing an example of processing by a power receiving device according to the second embodiment. [Figure 14] This flowchart shows an example of processing by a power transmission device according to the third embodiment. [Figure 15] This is a flowchart showing an example of processing by a power receiving device according to the third embodiment. [Figure 16] This is a sequence diagram showing an example of processing for a power transmission device and a power receiving device according to the first embodiment. [Figure 17] This is a sequence diagram showing an example of processing for a power transmission device and a power receiving device according to the second embodiment. [Figure 18] This is a sequence diagram showing an example of processing for a power transmission device and a power receiving device according to the second embodiment. [Modes for carrying out the invention]

[0009] The embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. Although the embodiments describe several features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the accompanying drawings, the same or similar configurations are given the same reference numeral. Each embodiment shows a wireless charging system to which a wireless power transmission system is applied. As an example, wireless power transmission based on the standards formulated by the Wireless Power Consortium (WPC), a standardization organization for wireless charging (hereinafter referred to as the WPC standard), will be described. An example of a WPC standard is the Qi standard.

[0010] [First Embodiment] This embodiment will be described with reference to the drawings. Figure 1 is a diagram showing an example of the configuration of a wireless charging system according to the first embodiment. This wireless charging system comprises a power transmission device 100, a power receiving device 200, and a charging cradle (Interface Surface) 300.

[0011] In the following, for the sake of brevity, the power receiving device 200 may be referred to as RX200 and the power transmitting device 100 as TX100. The detailed configurations of TX100 and RX200 will be described later using Figures 2 and 3.

[0012] The RX200 is an electronic device that receives power wirelessly from the TX100 and charges its internal battery when placed on the charging cradle 300. The TX100 is an electronic device that wirelessly transmits power to the RX200 when it is placed on the charging cradle 300. Since the charging cradle 300 constitutes part of the TX100, in the following, when the RX200 is "placed on the charging cradle 300", it may be referred to as "placed on the TX100". The spatial range in which the RX200 can receive power from the TX100 is schematically shown in Figure 1 by the area of ​​the dotted line frame 400. The RX200 and TX100 may have functions to perform applications other than wireless charging. For example, the RX200 is a smartphone, and the TX100 is an accessory device for charging the RX200's battery. However, this disclosure is not limited to this example.

[0013] Next, with reference to Figure 2, an example configuration of the power transmission device 100 will be described. Figure 2 is a functional block diagram showing an example configuration of the power transmission device 100. TX100 includes a control unit 101, a power supply unit 102, a power transmission unit 103, a first communication unit 104, a power transmission antenna (power transmission coil) 105, a memory 106, a resonant capacitor 107, a switch unit 108, a second communication unit 109, and a user interface unit 110. Hereinafter, the user interface will be referred to as UI. In Figure 2, each functional block element is shown as a separate entity, but any multiple functional block elements may be implemented as the same hardware module (for example, on the same chip).

[0014] The control unit 101 controls the entire TX100 by executing a control program stored in the memory 106. The control unit 101 also performs power transmission control, including communication for device authentication in the TX100. Furthermore, the control unit 101 can perform control for applications other than wireless power transmission. The control unit 101 is configured to include one or more processors, such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). Alternatively, the control unit 101 may be configured to include hardware such as an Application Specific Integrated Circuit (ASIC). The control unit 101 may also be configured to include an array circuit such as an FPGA (Field Programmable Gate Array) compiled to perform predetermined processing. The control unit 101 can perform processing to store information that should be stored during the execution of various processes in the memory 106, and can perform timing processing using a timer (not shown).

[0015] The power supply unit 102 supplies power to each functional block element. The power supply unit 102 includes, for example, a power connection circuit to the commercial power supply and a battery. The battery is charged by power supplied from the commercial power supply.

[0016] The power transmission unit 103 converts the DC power or AC power input from the power supply unit 102 into AC power in the frequency band used for wireless power transmission, and inputs the converted AC power to the power transmission antenna 105 to generate electromagnetic waves for the RX200 to receive power. For example, the power transmission unit 103 is equipped with an inverter and converts the DC voltage supplied by the power supply unit 102 into an AC voltage using a switching circuit in a half-bridge or full-bridge configuration. The power transmission unit 103 includes a plurality of FETs (Field Effect Transistors) that constitute the bridge and a gate driver that controls the ON / OFF state of the plurality of FETs.

[0017] The power transmission unit 103 controls the intensity of the electromagnetic waves (transmitted power) output by adjusting the voltage (transmission voltage) or current (transmission current), or both, input to the power transmission antenna 105. The strength of the electromagnetic waves (strength of the transmitted power) is controlled by the magnitude of the transmission voltage or transmission current.

[0018] Alternatively, the power transmission unit 103 controls the intensity of the electromagnetic waves it outputs (power transmission) by adjusting the voltage, current, or both input to the inverter it has. The voltage input to this inverter will be referred to as the inverter input voltage below. The current input to this inverter will be referred to as the inverter input current below. The strength of the electromagnetic waves (strength of the power transmission) is controlled by the magnitude of the inverter input voltage or inverter input current.

[0019] Alternatively, the power transmission unit 103 controls the intensity of the electromagnetic waves (transmitted power) by adjusting the voltage, current, or both output from the inverter of the power transmission unit 103. The voltage output from this inverter will be referred to as the inverter output voltage below. The current output from this inverter will be referred to as the inverter output current below. The strength of the electromagnetic waves (strength of the transmitted power) is controlled by the magnitude of the inverter output voltage or inverter output current.

[0020] The power transmission unit 103 controls the output power of AC frequency electromagnetic waves so that it can start or stop power transmission by the power transmission antenna 105 or control the intensity of the electromagnetic waves to be output, based on instruction signals from the control unit 101. The power transmission unit 103 is also assumed to have the power supply capacity to output / supply 15 watts (W) of power to the charging section of the power receiving device 200 which complies with the WPC standard.

[0021] The first communication unit 104 is connected to the control unit 101 and the power transmission unit 103, and communicates with the RX200 for power transmission control based on the WPC standard. The first communication unit 104 performs frequency shift modulation of the electromagnetic waves output from the power transmission antenna 105 and transmits information to the RX200 for communication. The first communication unit 104 also demodulates the electromagnetic waves transmitted from the power transmission antenna 105, which have been modulated by the RX200, and obtains the information transmitted by the RX200. Communication by the first communication unit 104 is performed by superimposing a communication signal on the electromagnetic waves transmitted from the power transmission antenna 105. The first communication unit 104 performs so-called in-band communication.

[0022] Memory 106 can store information regarding the status of TX100 and RX200, in addition to the control program. This information includes the power transmission value, power reception value, etc. Information regarding the status of TX100 is acquired by the control unit 101. Information regarding the status of RX200 is acquired by the control unit of RX200 and can be received by the first communication unit 104 or the second communication unit 109, which will be described later.

[0023] The switch unit 108 is connected in parallel to the series circuit of the resonant capacitor 107 and the power transmitting antenna 105. The control unit 101 transmits a control signal to the switch unit 108 to control its ON / OFF state. The power transmitting antenna 105 is connected to the resonant capacitor 107. When the switch unit 108 is turned ON and short-circuited by the control signal from the control unit 101, the power transmitting antenna 105 and the resonant capacitor 107 form a series resonant circuit and resonate at a specific frequency fA. At this time, current flows through the closed circuit formed by the power transmitting antenna 105, the resonant capacitor 107 and the switch unit 108. On the other hand, when the switch unit 108 is turned OFF and the circuit is opened by the control signal from the control unit 101, power is supplied to the power transmitting antenna 105 and the resonant capacitor 107 from the power transmitting unit 103.

[0024] The second communication unit 109 is connected to the control unit 101 and communicates with the RX200 using a standard different from the WPC standard. For example, the second communication unit 109 communicates with the RX200 using an antenna (not shown) different from the transmitting antenna 105. Examples of communication methods used by the second communication unit 109 include wireless LAN (Local Area Network), Bluetooth® Low Energy (BLE), and NFC (Near Field Communication). For BLE, any communication method compatible with Bluetooth standard version 4.0 or later is acceptable. The frequency band used for power transmission from the transmitting antenna 105 is different from the frequency band used for communication by the second communication unit 109. The second communication unit 109 performs so-called out-of-band communication.

[0025] Regarding communication between the TX100 and the RX200, the TX100 may selectively use one of several communication standards to communicate with the RX200. For example, the following communication configurations using multiple communication standards selectively are possible. • Communication based on the first standard (WPC standard) between the first communication unit 104 of TX100 and the first communication unit 204 of RX200 (see Figure 3). • Communication based on a second standard (a standard other than the WPC standard) between the second communication unit 109 of TX100 and the second communication unit 212 of RX200 (see Figure 3).

[0026] The UI unit 110 is connected to the control unit 101 and provides various outputs to the user. These outputs include screen displays, blinking and color changes of LEDs (Light Emitting Diodes), audio output from the speaker, and vibration of the TX100 unit. The UI unit 110 is implemented using an LCD panel, speaker, vibration motor, etc.

[0027] Next, referring to FIG. 3, a configuration example of the power receiving device 200 will be described. FIG. 3 is a functional block diagram showing a configuration example of the power receiving device 200. RX200 includes a control unit 201, a UI unit 202, a power receiving unit 203, a first communication unit 204, a power receiving antenna 205, a charging unit 206, a battery 207, and a memory 208. RX200 further includes a first switch unit 209, a second switch unit 210, a resonance capacitor (resonance capacitor) 211, a second communication unit 212, and a third switch unit 213. In the present embodiment, an example in which the functional block elements in FIG. 3 are individual elements is shown, but a plurality of functional block elements may be realized as one hardware module (for example, within the same chip).

[0028] The control unit 201 controls each functional block element of RX200 by executing a control program stored in the memory 208. Further, the control unit 201 can perform control for executing applications other than wireless power transmission. The control unit 201 includes one or more processors such as a CPU or an MPU. Also, the entire RX200 (for example, the entire smartphone) can be controlled in cooperation with the OS (Operating System) being executed by the control unit 201. Alternatively, the control unit 201 is composed of hardware such as an ASIC, or includes an array circuit such as an FPGA compiled to execute predetermined processing. The control unit 201 stores information to be stored during the execution of various processes in the memory 208, and can execute time measurement processing using a timer (not shown).

[0029] The UI unit 202 is connected to the control unit 201 and performs various outputs to the user. The various outputs are operations such as screen display, blinking or color change of an LED, voice output by a speaker, and vibration of the RX200 main body. The UI unit 202 is realized by a liquid crystal panel, a speaker, a vibration motor, etc.

[0030] The power receiving unit 203 receives alternating current power (alternating current voltage and alternating current) generated by electromagnetic induction based on the electromagnetic wave radiated from the power transmitting antenna 105 of TX100 via the power receiving antenna (power receiving coil) 205. Then, the power receiving unit 203 converts the alternating current power into direct current or alternating current power of a predetermined frequency and supplies power to the charging unit 206. The charging unit 206 charges the battery 207. The power receiving unit 203 includes a rectifying unit (rectifier, rectifying circuit) and a voltage control unit necessary for supplying power to the load in RX200. The rectifying unit converts the alternating current voltage and alternating current from the power transmitting antenna received via the power receiving antenna 205 into a direct current voltage and direct current. This direct current voltage is hereinafter referred to as the rectifying unit output voltage. Also, this direct current is hereinafter referred to as the rectifying unit output current. The voltage control unit converts the level of the direct current voltage (rectifying unit output voltage) output by the rectifying unit to a predetermined level. The predetermined level is the level of the direct current voltage at which operations of the control unit 201, the charging unit 206, etc. are possible. The power receiving unit 203 supplies power for charging from the charging unit 206 to the battery 207. Assume that the power receiving unit 203 has the power supply capacity to output 15 watts (W) of power to the charging unit 206.

[0031] The first communication unit 204 communicates for power receiving control based on the WPC standard with the first communication unit 104 of TX100. The first communication unit 204 is connected to the power receiving antenna 205 and the control unit 201. The first communication unit 204 demodulates the electromagnetic wave input from the power receiving antenna 205 and acquires the information transmitted from TX100. The first communication unit 204 performs load modulation or amplitude modulation or backscatter modulation on the input electromagnetic wave and superimposes a signal regarding the information to be transmitted to TX100 on the electromagnetic wave to communicate with TX100

[0032] In addition to the control program, the memory 208 stores information regarding the states of TX100 and RX200, etc. The information regarding the state of RX200 is acquired by the control unit 201. Also, the information regarding the state of TX100 is acquired by the control unit 101 of TX100 and can be received by the first communication unit 204 or the second communication unit 212 described later.

[0033] The second communication unit 212 is connected to the control unit 201 and communicates with the TX100 using a standard different from the WPC standard. For example, the second communication unit 212 communicates with the TX100 using an antenna different from the receiving antenna 205. Examples of communication methods used by the second communication unit 212 include wireless LAN, BLE, and NFC. For BLE, any communication method compatible with Bluetooth standard version 4.0 or later is acceptable. The frequency band used when receiving power with the receiving antenna 205 is different from the frequency band used by the second communication unit 212 for communication.

[0034] Regarding communication between the TX100 and the RX200, the RX200 may selectively use one of several communication standards to communicate with the TX100. For example, the following communication configurations using multiple communication standards selectively are possible. • Communication based on the first standard (WPC standard) between the first communication unit 104 of TX100 and the first communication unit 204 of RX200. • Communication between the second communication unit 109 of TX100 and the second communication unit 212 of RX200, based on a second standard (a standard other than the WPC standard).

[0035] The first switch unit 209 is located between the charging unit 206 and the battery 207 and is controlled by the control unit 201. The first switch unit 209 has the function of controlling whether or not to supply the power received by the power receiving unit 203 to the battery 207, and the function of controlling the magnitude of the load. When the first switch unit 209 is turned OFF and opened by the control unit 201, the power received by the power receiving unit 203 is not supplied to the battery 207. When the first switch unit 209 is turned ON and short-circuited by the control unit 201, the power received by the power receiving unit 203 is supplied to the battery 207.

[0036] In Figure 3, the first switch unit 209 is located between the charging unit 206 and the battery 207, but the first switch unit 209 may also be located between the power receiving unit 203 and the charging unit 206.

[0037] Alternatively, the first switch unit 209 may be positioned between the closed circuit formed by the receiving antenna 205, the resonant capacitor 211, and the second switch unit 210, and the receiving unit 203. In this case, the first switch unit 209 has the function of controlling whether or not to supply the power received by the receiving antenna 205 to the receiving unit 203.

[0038] Furthermore, although the first switch unit 209 is described as a single functional block element in the example of Figure 3, it is possible to implement the first switch unit 209 as part of the charging unit 206 or the power receiving unit 203. Moreover, this disclosure is not limited to a configuration in which the first switch unit 209 is inserted in series between the charging unit 206 and the battery 207; the first switch unit 209 may also be inserted in parallel between the charging unit 206 and the battery 207. In this case, when the first switch unit 209 is turned OFF and opened by the control unit 201, the power received by the power receiving unit 203 is supplied to the battery 207. When the first switch unit 209 is turned ON and short-circuited by the control unit 201, the power received by the power receiving unit 203 is not supplied to the battery 207.

[0039] On the input side of the power receiving unit 203, the second switch unit 210 is connected in parallel with the resonant capacitor 211. The resonant capacitor 211 is connected to the power receiving antenna 205 via the third switch unit 213. The second switch unit 210 and the third switch unit 213 are controlled by the control unit 201. The third switch unit 213 has the function of controlling whether or not to open the terminals of the power receiving antenna 205. When the control unit 201 turns the third switch unit 213 OFF, the terminals of the power receiving antenna 205 are open. When the control unit 201 turns the third switch unit 213 ON, the power receiving antenna 205 is connected to the power receiving unit 203 via the resonant capacitor 211.

[0040] When the control unit 201 turns on the third switch unit 213 and the second switch unit 210 turns on and short-circuits, the receiving antenna 205 and the resonant capacitor 211 form a series resonant circuit and resonate at a specific frequency fB. At this time, current flows through the closed circuit formed by the receiving antenna 205, the resonant capacitor 211 and the second switch unit 210, but no current flows to the receiving unit 203. On the other hand, when the second switch unit 210 turns off and the circuit is opened, the power received by the receiving antenna 205 and the resonant capacitor 211 is supplied to the receiving unit 203. Note that this disclosure is not limited to the example in Figure 3, and the second switch unit 210 may be placed between the receiving antenna 205 and the resonant capacitor 211. When the third switch unit 213 is ON and the second switch unit 210 is ON, the terminals of the receiving antenna 205 are short-circuited. Furthermore, the third switch unit 213 may be positioned between the resonant capacitor 211 and the power receiving unit 203.

[0041] In this wireless charging system, the TX100 and RX200 transmit wireless power between the transmitting antenna 105 and the receiving antenna 205 in accordance with the WPC standard. The WPC standard defines the agreed-upon load power level between the RX200 and TX100 as a value called Guaranteed Load Power (hereinafter referred to as "GP"). Load power is the power consumed by the load. For example, GP represents the power value at which the output from the RX200 to the load is guaranteed even if the coupling between the receiving antenna 205 and the transmitting antenna 105 weakens and the power transmission efficiency decreases due to a change in the relative positions of the RX200 and TX100. In this specification, the coupling state between the transmitting antenna (transmitting coil) 105 and the receiving antenna (receiving coil) 205 may also be referred to as the coupling state between the TX100 and RX200. The load of the RX200 is the charging unit 206, the battery 207, etc., and the value of GP corresponds to the power that is guaranteed to be output from the power receiving unit 203. Alternatively, the value of GP corresponds to the power that is guaranteed to be output from the rectifier unit of the power receiving unit 203. For example, let's assume that the value of GP is 5 (watts) and the positional relationship between the power receiving antenna 205 and the power transmitting antenna 105 changes. In this case, even if the power transmission efficiency decreases, the TX100 will perform power transmission control so that it can output 5 watts to the load of the RX200. Furthermore, GP is determined by negotiation between the TX100 and the RX200. Note that this disclosure is not limited to GP, and this embodiment can be applied to a configuration in which power transmission and reception are performed with power determined by negotiation between the TX100 and the RX200.

[0042] Furthermore, when transmitting power from TX100 to RX200, we consider the case where an object is present near TX100. In this case, the object is one that may affect the power transmission from TX100 to RX200, and is a different object (foreign object) from RX200. Electromagnetic waves for power transmission may affect the foreign object, potentially causing a temperature rise or destruction of the foreign object. In this disclosure, a foreign object is an object that is neither part of the power receiving device and the product into which the power receiving device is incorporated, nor part of the power transmitting device and the product into which the power transmitting device is incorporated, but which may generate heat when exposed to a power signal. Examples of foreign objects include paper clips and IC cards. Objects that are essential parts of the power receiving device and the product into which the power receiving device is incorporated, or the power transmitting device and the product into which the power transmitting device is incorporated, but which may unintentionally generate heat when exposed to the radio power transmitted by the power transmitting antenna, are not considered foreign objects.

[0043] The WPC standard specifies a method to suppress the temperature rise and damage of foreign objects by stopping power transmission when foreign objects are present. Specifically, the power transmission device 100 can detect the presence of foreign objects on the charging base 300. The Power Loss method is a method of detecting foreign objects by the difference between the power transmitted by TX100 and the power received by RX200. The Q-value measurement method is a method of detecting foreign objects by the change in the Quality Factor (also called Q-factor, quality coefficient, Q value, etc.) of the power transmission antenna 105 (power transmission coil) in TX100. Alternatively, the Q-value measurement method is a method of detecting foreign objects by the change in the Quality Factor of the resonant circuit including the power transmission antenna 105 and the resonant capacitor 107 in TX100. In this disclosure, the Quality Factor of the power transmission antenna 105 and the Quality Factor of the resonant circuit including the power transmission antenna 105 and the resonant capacitor 107 are referred to as the Quality Factor related to the power transmission antenna 105. However, the foreign objects detected by TX100 are not limited to objects located on the charging base 300. TX100 can detect foreign objects located in its vicinity. For example, TX100 can detect foreign objects located within its power transmission range.

[0044] Referring to Figure 4, we will explain foreign object detection based on the Power Loss method specified in the WPC standard. In Figure 4, the horizontal axis represents the power transmitted by TX100, and the vertical axis represents the power received by RX200. On the graph line shown by the straight line segment 1002, point 1000 corresponds to the first transmitted power value Pt1 and the first received power value Pr1, and point 1001 corresponds to the second transmitted power value Pt2 and the second received power value Pr2. On the same graph line, point 1003 corresponds to the third transmitted power value Pt3 and the third received power value Pr3. The foreign objects to be detected are conductive metal pieces, etc.

[0045] First, TX100 transmits power to RX200 at a first transmission power value Pt1, and RX200 receives power at a first reception power value Pr1. Hereafter, this state will be referred to as the Light Load state. Then, TX100 stores the first transmission power value Pt1 (for example, in memory 106). At this time, RX200 performs load control so that the power received is the minimum power. Alternatively, RX200 performs load control so that the power received is within a predetermined range or below a predetermined threshold. Here, in "power within a predetermined range" or "power below a predetermined threshold," "power" refers to power that is approximately 10% of the Reference Power, which will be described later. Furthermore, RX200 may disconnect the load from the receiving antenna 205 so that the received power is not supplied to the load (charging unit 206, battery 207, etc. in Figure 3). Alternatively, RX200 may control the load so that a predetermined power is supplied to the load. This can be achieved by controlling the first switch unit 209. Subsequently, RX200 notifies TX100 of the first received power value Pr1 by transmitting a signal relating to the first received power value Pr1 to TX100. Upon receiving the signal relating to the first received power value Pr1 from RX200, TX100 calculates the power loss between TX100 and RX200. The power loss at this time is Pt1-Pr1 (=Ploss1). TX100 can generate a calibration point (hereinafter abbreviated as CP) 1000 that shows the correspondence between Pt1 and Pr1.

[0046] Next, TX100 changes the transmission power value to the second transmission power value Pt2 and transmits power to RX200, which receives power at the second received power value Pr2. Hereafter, this state will be referred to as the Connected Load state (load connected state, maximum load state). Then, TX100 stores the second transmission power value Pt2 (for example, in memory 106). At this time, RX200 performs load control so that the power received is the maximum power. Here, "maximum power" is a power value close to the Reference Power, which will be described later. Alternatively, RX200 performs load control so that the power received is within a predetermined range or above a predetermined threshold. For example, RX200 connects the receiving antenna 205 to the load so that the received power is supplied to the load. These can be achieved by controlling the first switch unit 209. Next, RX200 notifies TX100 of the second power received value Pr2 by transmitting a signal related to the second power received value Pr2 to TX100. Upon receiving the signal related to the second power received value Pr2 from RX200, TX100 calculates the power loss between TX100 and RX200. The power loss at this time is Pt2-Pr2 (=Ploss2). TX100 can then generate CP1001, which shows the correspondence between Pt2 and Pr2.

[0047] TX100 performs linear interpolation between CP1000 and CP1001 to generate line segment 1002. Line segment 1002 shows the relationship between transmitted power and received power in a state in which no foreign objects are detected in the vicinity of TX100 and RX200 (hereinafter referred to as the first detection state). Based on line segment 1002, TX100 can estimate the power value that RX200 will receive when power is transmitted at a predetermined transmitted power in the first detection state. For example, consider the case where TX100 transmits power at a third transmitted power value Pt3. In this case, TX100 can estimate the third received power value Pr3 that RX200 will receive from point 1003 on line segment 1002, which corresponds to Pt3.

[0048] As described above, based on multiple combinations of the power transmission value of TX100 and the power reception value of RX200 measured while varying the load, the power loss between TX100 and RX200 according to the load can be determined. Furthermore, by interpolation processing from multiple combinations of power transmission and reception values, the power loss between TX100 and RX200 for all loads can be estimated. The calibration process performed by TX100 and RX200 to obtain the combination of power transmission and reception values ​​is called the "Power Loss method Calibration process." The Calibration process is also abbreviated as CAL. In addition, performing the Calibration process again after it has been executed once to update or add calibration points is called the Recalibration process, and is abbreviated as ReCAL.

[0049] Let's assume that after CAL processing using the Power Loss method, TX100 actually transmits power to RX200 at the third transmission power value Pt3, and TX100 receives a signal from RX200 regarding the received power value Pr3* (is notified of the received power value Pr3*). This signal regarding the received power value Pr3* is the Received Power data packet (mode0) specified in the WPC standard, but other messages may be used. Hereafter, the Received Power data packet (mode0) will be referred to as RP0. RP0 contains the value of the received power value Pr3*. TX100 calculates Pr3-Pr3* (=Ploss_FO) by subtracting the received power value Pr3* actually notified by RX200 from the received power value Pr3 in the first detection state. Ploss_FO can be estimated as the power consumed by foreign objects if they are present in the vicinity of TX100 and RX200, i.e., power loss. Hereinafter, the state in which a foreign object is detected near the TX100 and RX200 will be referred to as the second detection state.

[0050] In the second detection state, TX100 compares the power loss Ploss_FO that would have been consumed by the foreign object with a predetermined threshold value. If the value of the power loss Ploss_FO exceeds the threshold value, TX100 can determine that a foreign object is present. Alternatively, TX100 obtains the third power reception value Pr3 in the first detection state from RX200, and determines in advance the power loss Pt3 - Pr3 (= Ploss3) between TX100 and RX200.

[0051] Next, TX100 obtains the power reception value Pr3* from RX200 in the second detection state, and calculates the power loss Pt3 - Pr3* (= Ploss3*) between TX100 and RX200 in the second detection state. Then, TX100 can estimate the power loss Ploss_FO using Ploss3* - Ploss3.

[0052] As described above, there are two methods for calculating Ploss_FO in the second detection state. ·The first method of calculating Ploss_FO from Pr3 - Pr3*. ·The second method of calculating Ploss_FO from Ploss3* - Ploss3.

[0053] In this embodiment, basically the second method will be described, but the content of this embodiment is also applicable to the first method.

[0054] Next, with reference to Figure 5, we will explain foreign object detection based on the Q-value measurement method specified in the WPC standard. Figure 5(A) is a schematic circuit diagram illustrating the Quality Factor measurement method using the Q-value measurement method. The AC power supply 901 corresponds to the power supply that outputs AC power generated by the power transmission unit 103 of TX100. The power transmission antenna 902 corresponds to the power transmission antenna 105, and the capacitor 903 corresponds to the resonant capacitor 107. The power transmission antenna 902 and the capacitor 903 are connected in series. The voltage value V8 is a voltage value at a predetermined frequency generated by the power transmission unit 103 to operate the wireless power transmission system (wireless charging system). The voltage value V9 is the voltage value applied to the power transmission antenna 902. Here, it is assumed that TX100 can change the frequency related to the voltage value. Furthermore, voltage values ​​V8 and V9 are the voltage values ​​measured by TX100 when TX100 transmits Analog Ping (hereinafter referred to as "AP") or Digital Ping (hereinafter referred to as "DP") to RX200. Note that since voltage values ​​V8 and V9 are AC voltage values, their RMS values ​​may also be used.

[0055] Figure 5(B) shows an example of the measurement results of V9 / V8 against frequency, with a peak at 100 kHz. The horizontal axis is the frequency axis, and the vertical axis represents the voltage ratio "V9 / V8". Since V9 / V8 represents the Quality Factor related to the transmitting antenna 902, its value changes when an object is placed near the transmitting antenna 902. The change in Quality Factor differs depending on whether an object is placed on TX100, whether RX200 is placed on TX100, whether foreign matter (metal fragments, etc.) is placed on TX100, and whether RX200 and foreign matter are placed on TX100.

[0056] In the Negotiation phase, as defined in the WPC standard and described later, the TX100 receives a FOD Status data packet signal from the RX200. The FOD Status data packet includes the Reference Quality Factor Value and the Reference Resonance Frequency Value. The Reference Quality Factor Value is the Quality Factor that can be measured at the terminal of the power transmission antenna of the test TX100 when the RX200 is mounted on the test TX100 and no foreign objects are nearby. The Reference Resonance Frequency Value is as follows: it is the resonant frequency calculated from the inductance value that can be measured at the terminal of the power transmission antenna of the test TX100 when the RX200 is mounted on the test TX100 and no foreign objects are nearby. Using the Q-value measurement method, a threshold is set based on the Reference Quality Factor Value. Foreign object detection is performed by comparing this threshold with the Quality Factor obtained from the actually measured V9 / V8. Alternatively, a threshold can be set based on the Reference Resonance Frequency Value. Foreign object detection is performed by comparing this threshold with the resonance frequency, which is actually determined by measuring V9 / V8.

[0057] In this embodiment, the RX200 and TX100 communicate for power transmission and reception control based on the WPC standard. The WPC standard defines multiple phases, including the Power Transfer phase in which power transmission is performed and one or more phases prior to actual power transmission. Communication for necessary power transmission and reception control is performed in each phase. For example, foreign object detection using the Power Loss method is performed in the Power Transfer phase based on data obtained in the Calibration phase. Foreign object detection using the Q-value measurement method is performed before power transmission (before Digital Ping transmission and in the Negotiation phase or Renegotiation phase).

[0058] The WPC standard includes three phases prior to power transmission: the Selection phase, the Ping phase, and the Configuration phase. In addition, there are the Negotiation phase and the Calibration phase. The processing of each phase is described below.

[0059] During the Selection phase, the TX100 intermittently transmits Analog Pings to detect when an object is placed on the TX100's charging base. Analog Ping is a short-duration power signal applied to detect the presence of an object. However, this power signal does not activate the control unit of the power receiving device. For example, it detects when an RX200 or a conductive piece is placed on the charging base. The TX100 detects either or both the voltage and / or current values ​​of the transmitting antenna 105 when the Analog Ping is transmitted. If the voltage value falls below a threshold, or the current value exceeds a threshold, the TX100 determines that an object is present and transitions to the Ping phase. Alternatively, if the Quality Factor calculated from the voltage value satisfies a predetermined condition, or if the Quality Factor calculated from the current value satisfies a predetermined condition, the TX100 determines that an object is present and transitions to the Ping phase.

[0060] In the Ping phase, TX100 transmits a Digital Ping, which has a higher power output than Analog Ping. Digital Ping is a power signal that activates the control unit of RX200, which is mounted on top of TX100. RX200 notifies TX100 of the received voltage value. In this way, TX100 recognizes that the object detected in the Selection phase is RX200 by receiving a response from RX200 that has received the Digital Ping. Upon receiving notification of the received voltage value from RX200, TX100 transitions to the Configuration phase. Also, before transmitting Digital Ping, TX100 measures the Quality Factor related to the transmitting antenna 105, for example, using Analog Ping. This measurement result is used when performing foreign object detection processing using the Q-value measurement method. Note that depending on the version of the WPC standard, the Selection phase described above may be included as part of the Ping phase and referred to as the Ping phase.

[0061] During the Configuration phase, TX100 identifies RX200 and obtains device configuration information (capability information) from RX200. RX200 transmits an ID data packet and a Configuration data packet. The ID data packet contains RX200's identifier information, and the Configuration data packet contains RX200's device configuration information (capability information). Upon receiving the ID data packet and Configuration data packet signals, TX100 responds with an acknowledgment (ACK). The Configuration phase then ends.

[0062] In the Negotiation phase, the GP value is determined based on the GP value requested by RX200 and the power transmission capacity of TX100. TX100 also receives an FOD Status data packet from RX200, which includes the Reference Quality Factor Value and Reference Resonance Frequency Value. In the Q-value measurement method, the presence or absence of foreign matter is determined based on thresholds using the Reference Quality Factor Value and Reference Resonance Frequency Value. TX100 performs foreign matter detection processing using the Q-value measurement method according to the request from RX200. Furthermore, the WPC standard specifies a method where, after transitioning to the Power Transfer phase, the same processing as the Negotiation phase is performed again at the request of RX200. The phase in which these processes are performed after transitioning from the Power Transfer phase is called the Renegotiation phase.

[0063] In the Calibration phase, the Power Loss Calibration process (hereinafter referred to as "Power Loss Calibration Process") is performed based on the WPC standard. The RX200 also notifies the TX100 of a predetermined power received value, allowing the TX100 to make adjustments for efficient power transmission. The predetermined power received value is, for example, the power received under light load conditions or connected load conditions. The power received value notified to the TX100 is used for foreign object detection processing using the Power Loss method.

[0064] In the Power Transfer phase, the TX100 and RX200 perform control for starting and continuing power transmission, error handling, and stopping power transmission upon full charge. The TX100 and RX200 perform communication processing for these power transmission and reception control operations. For example, when performing wireless power transmission based on the WPC standard, the transmitting antenna 105 and receiving antenna 205 are used, and communication is performed by superimposing signals onto the electromagnetic waves transmitted from the transmitting antenna 105 or the receiving antenna 205. The range in which communication based on the WPC standard is possible between the TX100 and RX200 is the same as the power transmission range of the TX100. Depending on the version of the WPC standard, the Calibration phase described above may also be referred to as the Power Transfer phase, as it is part of the Power Transfer phase.

[0065] Next, the functions of the control unit of TX100 will be described with reference to Figure 6. Figure 6 is a block diagram showing an example of the functional configuration of the control unit 101 of the power transmission device 100 (TX100). The control unit 101 includes a communication control unit 301, a power transmission control unit 302, a measurement unit 303, a setting unit 304, and a state detection unit 305.

[0066] The communication control unit 301 performs communication control with the RX200 based on the WPC standard via the first communication unit 104, or performs communication control with the RX200 via the second communication unit 109.

[0067] The power transmission control unit 302 controls the power transmission unit 103 to control the power transmission to the RX200.

[0068] The measurement unit 303 measures the power transmitted to the RX200 via the power transmission unit 103 and measures the average transmitted power per unit time. The measurement unit 303 also measures the Quality Factor related to the power transmission antenna 105. The measurement unit 303 also measures the temperature using temperature sensors placed at multiple locations on the TX100. The measurement unit 303 also measures a quantity (e.g., coupling coefficient) that represents the electromagnetic coupling state between the power transmission antenna 105 and the power receiving antenna 205. The quantity representing the electromagnetic coupling state, such as the coupling coefficient, may also be called a coupling state index. In this specification, measuring the coupling state index and correcting the coupling state index (by correcting the coupling coefficient as described later) to obtain the corrected coupling state index may be considered as calculating or determining the coupling state between the power transmission antenna 105 and the power receiving antenna 205.

[0069] The setting unit 304 calculates and sets the threshold for foreign object detection in the Q-value measurement method and the threshold for foreign object detection in the Power Loss method using the method described above. The setting unit 304 also calculates and sets the threshold for foreign object detection or the threshold for detecting misalignment between TX100 and RX200 based on, for example, the coupling state index between the transmitting antenna 105 and the receiving antenna 205 measured by the measurement unit 303. The setting unit 304 also calculates and sets the threshold for foreign object detection or the threshold for detecting misalignment between TX100 and RX200 based on, for example, the temperature of the power transmission device measured by the measurement unit 303.

[0070] The state detection unit 305 performs state detection between the TX100 and the RX200. For example, the state detection unit 305 detects foreign objects present between the TX100 and the RX200, and also detects misalignment between the transmitting antenna 105 and the receiving antenna 205. More specifically, state detection processing is possible based on the Power Loss method, Q-value measurement method, temperature measured in the TX100, and the electromagnetic coupling state (e.g., coupling coefficient) between the transmitting antenna 105 and the receiving antenna 205. The state detection unit 305 can perform foreign object detection and misalignment detection between the transmitting antenna 105 and the receiving antenna 205 using other methods. For example, in a TX100 equipped with NFC communication functionality, the state detection unit 305 performs state detection processing using the NFC standard's peer detection function. In addition to detecting the presence or absence of foreign objects and the electromagnetic coupling state between the transmitting and receiving antennas, the state detection unit 305 can also detect changes in the state of the TX100. For example, the state detection unit 305 can detect an increase or decrease in the number of RX200s on the TX100.

[0071] The setting unit 304 sets a threshold that serves as a criterion for determining the presence or absence of foreign matter when the TX100 performs state detection. State detection can be, for example, based on the Power Loss method, the Q-value measurement method, state detection based on the temperature measured in the TX100, or state detection based on the coupling state index of the transmitting antenna 105 and the receiving antenna 205. The setting unit 304 can also set a threshold for determination necessary for state detection processing using other methods. Based on the threshold set by the setting unit 304 and the measurement results from the measurement unit 303, the state detection unit 305 can perform foreign matter detection processing and positional misalignment detection processing between the transmitting antenna 105 and the receiving antenna 205. For example, the state detection unit 305 can acquire data such as transmitted power, Quality Factor, temperature measured in the TX100, and coupling coefficient between the transmitting antenna 105 and the receiving antenna 205 as measurement results from the measurement unit 303.

[0072] The processes performed by the communication control unit 301, power transmission control unit 302, measurement unit 303, setting unit 304, and state detection unit 305 shown in Figure 6 can be implemented using programs executed by the CPU or other components of the control unit 101. Each process is executed in parallel according to an independent program, while maintaining synchronization between programs through event processing or the like. However, two or more of these processes may be incorporated into a single program.

[0073] Next, an example of the processing flow related to power transmission and reception control performed by TX100 and RX200 will be described. Figure 7 is a flowchart of an example of power transmission control processing performed by TX100. This processing is realized, for example, by the control unit 101 of TX100 executing a program read from memory 106. This processing may also be performed in response to the power being turned on to TX100, in response to the user of TX100 inputting a command to start a wireless power transmission application, or in response to TX100 being connected to a commercial power source and receiving power. This processing may also be started by other triggers.

[0074] In S1201, TX100 performs the processes defined as the Selection and Ping phases of the WPC standard and waits for RX200 to be placed. Specifically, TX100 repeatedly and intermittently transmits Analog Ping according to the WPC standard to detect objects within the power transmission range. For example, TX100 can detect when RX200 or conductive pieces are placed on the charging base 300. If TX100 detects the presence of an object within the power transmission range, it transmits a Digital Ping.

[0075] When TX100 receives a predetermined response to Digital Ping, it determines that the detected object is RX200 and that RX200 has been placed on the charging base 300. Here, the "predetermined response" is the Signal Strength (SIG) data packet transmitted by RX200. This packet includes a Signal Strength Value representing the signal strength of the signal received by RX200. The Signal Strength Value is calculated from the following parameters: the voltage output by the rectifier of the power receiving unit 203 measured by RX200 (rectifier output voltage), the voltage of the open circuit including the power receiving antenna 205 measured by RX200 (open circuit voltage), or the power received value measured by RX200.

[0076] Furthermore, before transmitting a Digital Ping, the TX100 measures the Quality Factor of the power transmission antenna 105. This measurement result is used when performing foreign object detection processing using the Q-value measurement method.

[0077] After the placement of the RX200 is detected, in S1202, the TX100 obtains (receives) identification information from the RX200 through the Configuration phase communication defined by the WPC standard. During the Configuration phase, the RX200 sends an Identification data packet (ID Packet) to the TX100. The ID Packet contains the Manufacturer Code and Basic Device ID, which are the identification information for each individual RX200, as well as information elements that can identify the version of the WPC standard it supports.

[0078] Furthermore, the RX200 sends a Configuration data packet to the TX100. The Configuration data packet contains the following capability information for the RX200. • Maximum Power Value or Reference Power, which is a value that identifies the maximum power that the RX200 can supply to a load. Information indicating whether the RX200 has the WPC standard negotiation function. • A parameter used in frequency-shifted modulation, a communication modulation method used when the TX100 transmits information to the RX200. • Information indicating whether the RX200 supports out-of-band communication functionality.

[0079] When TX100 receives the above packet from RX200, it sends an acknowledgment (ACK) to RX200, and the Configuration phase ends. Note that TX100 may obtain the identification information of RX200 by a method other than the Configuration phase communication of the WPC standard. The identification information for each RX200 may be the Wireless Power ID. Alternatively, it may be any other identification information that can identify the individual RX200, such as the Bluetooth Address (hereinafter referred to as "BD_ADDR") unique to the second communication unit 212 of RX200. Note that BD_ADDR is an 8-byte address used in BLE. BD_ADDR is a Public Address defined in the BLE standard that indicates, for example, the manufacturer of RX200 or the individual identification information of the BLE communication function (second communication unit 212). BD_ADDR may also be a Random Address.

[0080] Next, in S1203, TX100 determines the GP through negotiation with RX200 based on the request from RX200 and its own power transmission capacity. In S1203, the Negotiation phase of the WPC standard communication takes place. For example, RX200 notifies TX100 of the power value it requests by sending a Specific Request. TX100 determines whether to accept the request based on its own power transmission capacity and other conditions. If TX100 accepts the request, it sends an acknowledgment (ACK) to RX200; if it does not accept the request, it sends a negation (NACK) or NAK to RX200. The GP value determined through negotiation with RX200 will be the value requested by RX200 if TX100 accepts the request from RX200. If TX100 does not accept the request from RX200, the GP value may be a predetermined value as defined in the WPC standard (e.g., 5 watts). Furthermore, if the TX100 receives information indicating that the RX200 does not support the Negotiation phase (for example, S1302 described below), it will not perform Negotiation phase communication and will determine the GP value to a predetermined value. The predetermined value is, for example, a value specified in advance by the WPC standard (for example, 5 watts).

[0081] Furthermore, TX100 performs foreign object detection processing using the Q-value measurement method in accordance with requests from RX200. TX100 receives a FOD Status data packet from RX200. This packet includes the Reference Quality Factor Value and Reference Resonance Frequency Value mentioned above. Then, TX100 performs foreign object detection using the Q-value measurement method. This foreign object detection is performed based on the following information. • Quality Factor and resonant frequency of the transmitting antenna 105, as measured by TX100 before transmitting a Digital Ping. • A threshold value based on the Reference Quality Factor Value and Reference Resonance Frequency Value received by the TX100 from the RX200.

[0082] Next, in S1204, TX100 and RX200 perform the Calibration phase processing (CAL processing) of the WPC standard. In the Calibration phase, TX100 performs CAL processing using the Power Loss method based on the determined Reference Power value or GP value. First, RX200 transmits a signal to TX100 containing information about the power received under light load conditions (hereinafter referred to as the first reference power received information). Light load conditions include, for example, a load disconnection state, a load condition in which the power received value of RX200 is below a first threshold, or a load condition in which the power received value of RX200 is within a predetermined range (hereinafter referred to as the "first range"). In this embodiment, the first reference power received information is assumed to be 500 milliwatts (however, the first reference power received information is not limited to 500 milliwatts). The first reference power received information is information included in the Received Power data packet (mode1) specified in the WPC standard, but other messages may be used. Hereafter, Received Power data packet (mode1) will be referred to as RP1. TX100 determines whether to accept the first reference power information based on the Control Error Value contained in the Control Error (CE) data packet received from RX200. If TX100 accepts the first reference power information, it sends an acknowledgment (ACK) to RX200. If TX100 does not accept the first reference power information, it sends a negative response (NAK) to RX200.

[0083] Next, the RX200 performs processing to transmit a signal to the TX100 containing information about the power received in a load-connected state (hereinafter referred to as the second reference power received information). The load-connected state is, for example, the maximum load state, the load state in which the transmitted power value is equal to or greater than the second threshold, or the load state in which the power received by the RX200 is the maximum power. Here, "maximum power" is power close to the Reference Power. Alternatively, the load-connected state is the load state in which the power received by the RX200 falls within a predetermined range (hereinafter referred to as the "second range"). Here, the second range is a range of power values ​​higher than the first range. In this embodiment, the second reference power received information is set to 15 watts (however, the second reference power received information is not limited to 15 watts). The second reference power received information is information included in the Received Power data packet (mode2) specified in the WPC standard, but other messages may be used. Hereinafter, the Received Power data packet (mode2) will be referred to as RP2. Based on the Control Error Value contained in the Control Error (CE) data packet received from RX200, TX100 determines whether to accept the second reference power information. If TX100 accepts the second reference power information, it sends an acknowledgment (ACK) to RX200. If TX100 does not accept the second reference power information, it sends a negative response (NAK) to RX200. TX100 then sends an acknowledgment (ACK) to RX200 in response to the second reference power information and completes the CAL process.

[0084] Through the CAL processing described above, TX100 can calculate the amount of power loss between TX100 and RX200 in light-load and load-connected states based on the power transmission value of TX100 and the power reception values ​​included in the first and second reference power reception information. Furthermore, TX100 can calculate the amount of power loss between TX100 and RX200 for all power transmission values ​​that TX100 can take by performing interpolation processing between multiple power loss values. All power transmission values ​​that TX100 can take refer to any power within the range where the power reception received by RX200 in this embodiment ranges from 500 milliwatts to 15 watts. Note that the CAL processing described above is not required.

[0085] Subsequently, in S1205, TX100 transmits power until the RX200's battery 207 is fully charged. In S1205, communication of the Power Transfer phase according to the WPC standard takes place. RX200 repeatedly sends Control Error data packets (hereinafter referred to as "CE packets") to TX100 at time intervals of t_interval. t_interval is a value defined in the WPC standard, for example, 250 milliseconds. The CE packets contain a request for how much to increase or decrease the transmitted power. Based on the received CE packets, TX100 adjusts the transmitted power by controlling the current or voltage of the transmitting antenna 105. In other words, the CE packets contain parameter data for adjusting the transmitted power. By repeating this process, power transmission at the appropriate power level according to RX200's requests is performed in near real-time.

[0086] When the battery 207 is fully charged, the RX200 sends an End Power Transfer data packet (hereinafter referred to as the "EPT packet") to terminate the Power Transfer phase. The RX200 may send an EPT packet for reasons other than full charge. Also, when the Power Transfer phase is completed, the TX100 stops supplying power for charging the RX200.

[0087] Furthermore, if TX100 fails to receive the next CE packet after a time t_timeout has elapsed since the last CE packet was received, it determines that RX200 has been removed from the charging cradle 300. In this case, TX100 terminates the Power Transfer phase. t_timeout is a value defined by the WPC standard, for example, 1500 milliseconds.

[0088] The RX200 may send packets other than CE packets to the TX100 during the Power Transfer phase. For example, there is a Charge Status data packet that notifies the TX100 of the status of the RX200's battery 207. This packet contains a Charge Status Value that indicates the percentage of charge of the battery 207. When the TX100 receives the Charge Status data packet, it notifies the user of the charging status by displaying text or a diagram based on the Charge Status Value, for example, using the UI unit 110. The TX100 may receive the Charge Status data packet at any time and may notify the user at any time of its choosing.

[0089] During the Power Transfer phase, TX100 transmits power to RX200 and performs foreign object detection processing using the Power Loss method. For example, CAL processing calculates the amount of power loss between TX100 and RX200 in the first detection state during power transmission from the difference between the transmitted power value and the received power value. The calculated amount of power loss corresponds to the reference power loss when no foreign objects are present. Then, if TX100 determines that the difference between the amount of power loss between TX100 and RX200 measured during power transmission after CAL processing and the reference power loss is greater than or equal to a threshold, it determines that a second detection state has been reached.

[0090] Referring to Figure 8, an example of the processing flow related to power reception control performed by RX200 will be explained. This processing is achieved, for example, by the control unit 201 of RX200 executing a program read from memory 208.

[0091] In S1301, RX200 performs the processes defined as the Selection phase and Ping phase of the WPC standard and waits for itself to be placed on TX100. RX200 detects that it has been placed on TX100, for example, by detecting a Digital Ping from TX100.

[0092] When RX200 detects that it has been placed on TX100, in S1302 it sends a signal to TX100 containing its identification information via an ID Packet and a Configuration data packet. Note that the identification information of RX200 may be transmitted by a method other than the communication in the Configuration phase of the WPC standard. In addition, other identification information such as BD_ADDR may be used as long as it is information that can identify each individual RX200. Furthermore, in S1302, RX200 can also transmit information other than identification information to TX100.

[0093] Next, in S1303, RX200 transmits a signal to TX100 containing information about the power values ​​it requests, and negotiates with TX100 to determine the GP. In S1303, the Negotiation phase of the WPC standard communication takes place. RX200 transmits an FOD Status data packet to TX100. This packet includes the Reference Quality Factor Value and the Reference Resonance Frequency Value.

[0094] Next, in S1304, the RX200 and TX100 perform the Calibration phase (CAL processing) according to the WPC standard. The processing performed by the RX200 in this phase is as described above. Note that the CAL processing described above is optional.

[0095] Subsequently, in S1305, RX200 receives power until battery 207 is fully charged. The processing performed by RX200 in this phase is as described above. In the Power Transfer phase, RX200 and TX100 perform foreign object detection processing using the Power Loss method. In S1305, RX200 repeatedly sends CE packets at intervals of t_interval, and finally sends an EPT packet to TX100 to terminate processing.

[0096] Next, a method for measuring the coupling state index between the power transmission antenna and the power reception antenna in the MPP (Magnetic Power Profile) of the Qi standard will be described. The MPP is adopted in the standard "Qi2 (Qi standard v2.0)" of the wireless power reception standard "Qi". In the WPC standard, there are a BPP (Baseline Power Profile) that performs power transmission of 5 watts or less to RX200, an EPP (Extended Power Profile) that performs power transmission of 15 watts or less, and the above-mentioned MPP. Here, the power profile is a set of features that defines the compliance level of the power transmission device or the power reception device. The MPP has a function of accurately fixing the TX100 and the RX200 at a predetermined position. A plurality of means for accurately fixing the TX100 and the RX200 at a predetermined position can be considered. For example, the power transmission antenna (power transmission coil) of the TX100 and the power reception antenna (power reception coil) of the RX200 can be accurately opposed (directly opposed) by using the magnets built in the TX100 and the RX200 respectively. That is, in this case, the MPP can be said to be an extended function of the BPP and a profile (power profile) that uses magnets for alignment between the power transmission device and the power reception device. The magnet may be a permanent magnet or an electromagnet.

[0097] The TX100 calculates (estimates or reckons) k, which represents the coupling state (inductive coupling factor) between the TX100 and the RX200, est using the following formula. k est represents the coupling state (inductive coupling factor) between the power transmission coil of the TX100 and the power reception coil of the RX200. k est =E 0xg α 0rx p+E 1xg α 1rx Here, α 0rx =E 0gy / E 0gg and α 1rx =E 1gy / E 1ggAnd,

number

[0098] The above eigencoefficient is E 0xg , E 1xg , E 0gy , E 0gg , E 1gy and E 1gg These each mean the following:

[0099] Let E{a}{b}{c}, a is {0 or 1}, 0: The slope of linear curve fit. 1: The intercept of a linear curve fit. It means...

[0100] Furthermore, b is a description of the power transmission equipment. g: Power transmission equipment in system model x: General power transmission device It means...

[0101] Furthermore, c is a description of the power receiving device. g: Power receiving device of the system model y: General power receiving device It means...

[0102] Here, the "system model power transmission device" refers to the reference power transmission device. Hereafter, in this specification, the "system model power transmission device" will be referred to as the reference power transmission device. Similarly, the "system model power receiving device" refers to the reference power receiving device. Hereafter, in this specification, the "system model power receiving device" will be referred to as the reference power receiving device.

[0103] In other words, E 0gg and E 1ggThese are characteristic coefficients that represent the characteristics when the reference power transmission device and the reference power reception device are placed opposite each other. These characteristic coefficients are calculated in advance by measurement, and their values ​​are stored in memory 208 by RX200.

[0104] Also, E 0xg and E 1xg These are characteristic coefficients that represent the characteristics when the reference power receiving device and the power transmitting device to be actually used are placed opposite each other. These characteristic coefficients are calculated in advance by measurement, and their values ​​are stored in memory 106 by TX100.

[0105] Also, E 0gy and E 1gy These are characteristic coefficients that represent the characteristics when the reference power transmission device and the power receiving device to be actually used are placed opposite each other. These characteristic coefficients are calculated in advance by measurement, and their values ​​are stored in memory 208 by the RX200.

[0106] Figure 9(a) is a diagram illustrating the power transmission antenna and power transmission device enclosure. The power transmission device enclosure (housing) encloses the power transmission antenna (power transmission coil). In this specification, as shown in Figure 9(a), the distance from the bottom surface of the power transmission antenna (power transmission coil) to the interface surface (top and bottom surface) of the power transmission device enclosure is defined as dZ. PTX This is defined as follows. Therefore, dZ PTX This can be described as the distance between the power transmission antenna (power transmission coil) and the power transmission device enclosure.

[0107] Figure 9(b) is a diagram illustrating the receiving antenna and the receiving device enclosure. The receiving device enclosure (casing) contains the receiving antenna (receiving coil). In this specification, as shown in Figure 9(b), the distance from the bottom surface of the receiving antenna (receiving coil) to the interface surface (top and bottom surface) of the receiving device enclosure is defined as dZ. PRX This is defined as follows. Therefore, dZ PRXThis can be described as the distance between the receiving antenna (receiving coil) and the receiving device enclosure.

[0108] In the Qi standard, the dZ of the MPP reference power transmission device PTX The nominal value is 1.2 mm. Also, in the Qi standard, the dZ of the MPP reference power receiver. PRX The nominal value is 0.66 mm.

[0109] Also, V rect This is the output voltage after rectification in the RX200's rectifier circuit when the RX200 receives a Digital Ping. The RX200 is V rect After measuring, information regarding the measured value (information indicating the measured value) is transmitted to TX100.

[0110]

number

[0111] Also, V in This is the DC voltage input to the inverter of the TX100, as measured by the TX100, or the voltage output by the inverter of the TX100, as measured by the TX100.

[0112] α 0rx The RX200 holds E in memory 208 0gy and E 0gg Calculated by RX200, α 1rx The RX200 holds E in memory 208 1gy and E 1gg It is calculated by the RX200. The RX200 is α 0rx and α 1rx The values ​​are stored in memory 208, and information about these values ​​(information indicating these values) is sent to TX100. α 0rx and α 1rxThis is the ecosystem scaling coefficient or scaling factor.

[0113] E 0xg and E 1xg This is pre-stored in memory 106 by TX100.

[0114] The TX100 receives V from the RX200. rect Information regarding α 0rx Information regarding and α 1rx Information regarding the TX100 measurements

number

[0115] As described above, the TX100 is the same as the V measured by the RX200. rect The TX100 measured the following:

number

[0116] In the current Qi standard MPP, the TX100's dZ PTX This assumes an equivalent of 1.2 mm, and the aforementioned eigenfactors, scaling factor, and k est The calculation method is also designed under that premise. Therefore, the TX100's dZ PTX If the distance differs from 1.2 mm by a certain amount or more, the premise is broken, so k est This could potentially make it impossible to calculate accurately.

[0117] Therefore, below, the TX100 dZ PTX When the distance differs from 1.2 mm by a certain amount or more, k est A method for accurately calculating this will be explained using Figures 10 and 11.

[0118] Figure 10 is a flowchart showing an example of processing by TX100 according to the first embodiment. Figure 11 is a flowchart showing an example of processing by RX200 according to the first embodiment.

[0119] First, the RX200 is mounted on the TX100 (F1001, F1101). Then, the TX100 and RX200 perform the Ping phase processing described above (F1002, F1102).

[0120] Next, the RX200 is the TX100's dZ PTX Send a request to TX100 to send a packet containing information about (F1103).

[0121] The TX100 is a successor to the RX200, and the TX100's DZ PTX When a request to send a packet containing information is received (Yes in F1003), proceed to F1004. TX100 receives a packet from RX200 to TX100's dZ PTX If a request to send a packet containing information is not received (No in F1003), the process returns to F1003. In F1004, TX100's dZ PTX Send a packet containing information about the above to the RX200.

[0122] Here, the dZ PTX Information regarding dZ PTX This is information indicating the distance.

[0123] For example, dZ PTX Information indicating distance is dZ PTX The distance is such that it is "2.5mm" or "3.0mm", and the specific dZ PTX This is information indicating the distance.

[0124] Alternatively, dZ PTX The information indicating the distance is one of several predetermined distances, dZ PTX This is information indicating the corresponding distance. For example, let's assume that distances of "2.5mm", "3.0mm", and "3.5mm" are predetermined. Also, let's assume that the TX100 sends information "1" to the RX200 when the distance is "2.5mm", information "2" when the distance is "3.0mm", and information "3" when the distance is "3.5mm". And, for example, dZ PTX If the value is "3.0mm", the TX100 will send the information "2" to the RX200.

[0125] Alternatively, dZ PTX The information indicating the distance is the dZ PTX This information indicates whether the value is below a predetermined threshold or within a predetermined range. For example, TX100 is dZ for RX200. PTX If it is 3.0mm or more, send the information "1", dZ PTX If it is less than 3.0mm, it sends the information "0". Alternatively, for example, TX100 sends dZ to RX200. PTX If the value is "1.5mm or more but less than 2.0mm", it sends the information "1". Also, for example, TX100 sends the information to RX200, dZ PTX If the value is "2.0 mm or more, but less than 2.5 mm", it sends the information "2". Also, for example, the TX100 sends the information to the RX200, dZ PTX If the value is "2.5mm or more but less than 3.0mm", send the information "3".

[0126] The RX200 is a successor to the TX100, and the dZ PTX Determine whether or not a packet containing information about dZ has been received (F1104). RX200 receives from TX100, dZ PTX If a packet containing information about is received (Yes in F1104), proceed to F1105. RX200 receives information from TX100, dZ PTX If no packet containing information is received (No in F1104), return to F1104.

[0127] In F1105, RX200 is dZ PTX Selects a specific coefficient (information for calculating or determining the coupling state) related to the calculation of the coupling state according to the information about (that is, dZ PTX ). Hereinafter, the method for selecting the specific coefficient of RX200 will be described.

[0128] The "specific coefficient related to the calculation of the coupling state according to dZ PTX " selected by RX200 is E 0gy , E 0gg , E 1gy and E 1gg (therefore, the scaling factors α 0rx and α 1rx ). That is, the specific coefficient in which {b} in the above-mentioned E{a}{b}{c} is g (reference power transmission device) is the "specific coefficient related to the calculation of the coupling state according to dZ PTX " selected by RX200. In this embodiment, the dZ PTX of TX100 is different from the dZ PTX = 1.2 mm of the reference power transmission device. Therefore, for E 0gy , E 0gg , E 1gy and E 1gg , dZ PTX needs to be a coefficient representing the characteristics with respect to the reference power transmission device equivalent to the dZ PTX of TX100.

[0129] RX200 holds, for each of E 0gy , E 0gg , E 1gy and E 1gg , the value corresponding to the information about dZ PTX received from TX100 in F1104 (the value of dZ PTX ) in the memory 208. That is, RX200 holds, for example, the following information (1) to (3) (each of (1) to (3) is an example of the association information associating the distance between the power transmission coil and the enclosure and the information for calculating or determining the coupling state between the power transmission device and the power reception device). (1) dZ PTXE when = 2.5mm 0gy , E 0gg , E 1gy and E 1gg . (2) dZ PTX E when = 3.0 mm 0gy , E 0gg , E 1gy and E 1gg . (3) dZ PTX E when = 3.5mm 0gy , E 0gg , E 1gy and E 1gg .

[0130] Therefore, the RX200 receives the dZ from the TX100. PTX Based on the information, the dZ PTX E corresponding to 0gy , E 0gg , E 1gy and E 1gg Select this. Then, RX200 will use the selected eigenfactor E 0gy , E 0gg , E 1gy and E 1gg Therefore, scaling factor α 0rx and α 1rx Calculate and select.

[0131] Alternatively, another method is that the RX200 could, for example, use the dZ PTX E when = 2.5mm 0gy , E 0gg , E 1gy and E 1gg And, dZ PTX E when = 3.5mm 0gy , E 0gg , E 1gy and E 1gg The RX200 stores this information in memory 208. In other words, the RX200 stores correspondence information that associates the distance between the power transmission coil and the enclosure with the information for calculating or determining the coupling state between the power transmission device and the power receiving device. The RX200 then stores dZ PTX E when it is between 2.5mm and 3.5mm 0gy , E 0gg , E1gy and E 1gg This is calculated using linear interpolation. In other words, for the RX200, the horizontal axis is dZ. PTX Let the vertical axis be E 0gy , E 0gg , E 1gy and E 1gg Each of these has a graph (data) or formula calculated or determined by linear interpolation. The RX200 receives dZ from the TX100. PTX Information regarding (i.e., dZ) PTX E corresponding to ) 0gy , E 0gg , E 1gy and E 1gg The RX200 then calculates and selects the eigenfactor E from the graph (data) or formula. 0gy , E 0gg , E 1gy and E 1gg From, α 0rx and α 1rx Calculate and select. Note that linear approximation may be used instead of linear interpolation, in which case dZ PTX Three or more values ​​may be used. Also, N dZ (where N is an integer greater than or equal to 3) PTX When the value of is used for interpolation, the RX200 uses an N-1 order interpolation polynomial to interpolate the dZ received from the TX100. PTX Information regarding (i.e., dZ) PTX Alternatively, you may calculate and select the corresponding eigencoefficients.

[0132] Alternatively, the RX200 is dZ PTX You may also select the scaling factor itself (information for calculating or determining the coupling state) for calculating the coupling state accordingly. The following describes how to select the scaling factor for the RX200.

[0133] The RX200 selects "dZ PTX The scaling factor for calculating the coupling state according to α 0rx and α 1rx That is. The RX200 is α 0rx and α 1rx For each of them, dZPTX The corresponding values ​​are stored in memory 208. In other words, the RX200 stores, for example, the following information (1) to (3) (each of which is an example of correspondence information that associates the distance between the power transmission coil and the enclosure with information for calculating or determining the coupling state between the power transmission device and the power receiving device). (1) dZ PTX α when = 2.5mm 0rx and α 1rx . (2) dZ PTX α when =3.0mm 0rx and α 1rx . (3) dZ PTX α when =3.5mm 0rx and α 1rx .

[0134] Therefore, the RX200 receives the dZ from the TX100. PTX Based on the information, the dZ PTX α corresponding to 0rx and α 1rx Select this option.

[0135] Alternatively, another method is that the RX200 could, for example, use the dZ PTX α when = 2.5mm 0rx and α 1rx And, dZ PTX α when =3.5mm 0rx and α 1rx The RX200 stores this information in memory 208. In other words, the RX200 stores correspondence information that associates the distance between the power transmission coil and the enclosure with the information for calculating or determining the coupling state between the power transmission device and the power receiving device. The RX200 then stores dZ PTX α when it is between 2.5mm and 3.5mm 0rx and α 1rx This is calculated using linear interpolation. In other words, for the RX200, the horizontal axis is dZ. PTX Let the vertical axis be α 0rx and α 1rxEach of these has a graph (data) or formula calculated or determined by linear interpolation. The RX200 receives dZ from the TX100. PTX Information regarding (i.e., dZ) PTX ) corresponds to α 0rx and α 1rx The value is calculated and selected from the graph (data) or formula. Note that linear interpolation may be used instead of linear approximation; in this case, dZ PTX Three or more values ​​may be used. Also, N dZ (where N is an integer greater than or equal to 3) PTX When the value of is used for interpolation, the RX200 uses an N-1 order interpolation polynomial to interpolate the dZ received from the TX100. PTX Information regarding (i.e., dZ) PTX Alternatively, you may calculate and select the corresponding eigencoefficients.

[0136] Next, the RX200 has a scaling factor (α 0rx (Alpha0 Rx) and α 1rx The RX200 sends a predetermined packet containing information about (Alpha1 Rx) to the TX100 (F1106). This packet is an MPP-Extended Identification Packet (Qi MPP Extended Identification, MPP-XID data packet) as defined by the Qi standard. The RX200 sends the MPP-Extended Identification Packet to the TX100 during the Ping phase or Configuration phase described above. This packet contains the V measured by the RX200. rect This also includes information about [the subject].

[0137] TX100 determines whether or not it has received a scaling factor related to coupling state calculation from RX200 (F1005). If TX100 determines that it has received a scaling factor related to coupling state calculation from RX200 (Yes in F1005), it proceeds to F1006. If TX100 determines that it has not received a scaling factor related to coupling state calculation from RX200 (No in F1005), it returns to F1005.

[0138] In F1006, TX100 calculates the coupling state using the scaling factor for coupling state calculation received from RX200. Then, in F1007, TX100 transmits the calculated coupling state information to RX200. Then, in F1008, TX100 performs control according to the calculated coupling state. "Control according to the calculated coupling state" could mean, for example, that TX100 has multiple resonant capacitors 107 (not shown), and TX100 selects the optimal resonant capacitor 107 from among the multiple resonant capacitors according to the calculated coupling state. Additionally or alternatively, "control according to the calculated coupling state" could mean, for example, that TX100 selects a noise suppression circuit according to the calculated coupling state. Additionally or alternatively, "control according to the calculated coupling state" could mean, for example, that TX100 predicts the power that can be transmitted according to the calculated coupling state. Additionally or alternatively, "control according to the calculated coupling state" may mean, for example, that TX100 selects the optimal parameters for in-band communication according to the calculated coupling state.

[0139] At F1107, RX200 determines whether or not it has received information regarding the coupling state calculated by TX100. If RX200 determines that it has received information regarding the coupling state calculated by TX100 (Yes at F1107), it proceeds to F1108. If RX200 determines that it has not received information regarding the coupling state calculated by TX100 (No at F1107), it returns to F1104. At F1108, RX200 performs control according to the calculated coupling state based on the received information. "Control according to the calculated coupling state" may, for example, mean that RX200 has multiple resonant capacitors 211 (not shown), and RX200 selects the optimal resonant capacitor 211 from among the multiple resonant capacitors according to the coupling state. Additionally or alternatively, "control according to the calculated coupling state" may mean, for example, that RX200 selects a noise suppression circuit according to the coupling state. Additionally or alternatively, "control based on calculated coupling state" may mean, for example, that the RX200 predicts the power that can be received based on the coupling state. Additionally or alternatively, "control based on calculated coupling state" may mean, for example, that the RX200 selects the optimal parameters for in-band communication based on the coupling state.

[0140] Figure 16 is a sequence diagram showing an example of processing by TX100 and RX200 according to the first embodiment.

[0141] The RX200 is mounted on the TX100 (S1601, S1602). The TX100 and RX200 perform the Ping phase processing (S1603).

[0142] The RX200 is dZ PTX A request to send a packet containing information about dZ is sent to TX100 (S1604). TX100 then PTX A packet containing information about dZ is sent to RX200 (S1605). RX200 then... PTXSelect or calculate a scaling factor for calculating the coupling state based on the information provided (S1606). RX200 transmits the selected or calculated coefficient (scaling factor) for calculating the coupling state to TX100 (S1607).

[0143] TX100 transmits information about the calculated coupling state to RX200 (S1608). TX100 and RX200 then perform control according to the calculated coupling state (S1609).

[0144] Note that the order of operations in the TX100 and RX200 operation flow is not limited to the examples described above (for example, the examples shown in Figures 10, 11, and 16). Also, the operations of F1003-F1008 and F1103-F1108 are performed in the Ping phase or Configuration phase.

[0145] Furthermore, TX100 will send a predetermined packet to RX200 if RX200 sends a packet requesting TX100 to send a predetermined packet. Alternatively, TX100 may send a packet to RX200 even if RX200 does not send a packet requesting TX100 to send a packet.

[0146] RX200 sends a packet to TX100 if TX100 sends a packet requesting RX200 to send a packet. Alternatively, RX200 may send a packet to TX100 even if TX100 does not send a packet requesting RX200 to send a packet.

[0147] The same applies to embodiments other than this embodiment. The term "predetermined packet" is applicable to any packet.

[0148] By performing the above control on the TX100 and RX200, the TX100 will control the dZ PTX The reference power transmission device's dZ PTXEven if the value differs from 1.2 mm, it becomes possible to calculate a more precise coupling state between the TX100 and RX200. Then, based on the highly precise coupling state, the TX100 and RX200 can perform more appropriate control.

[0149] [Second Embodiment] In the first embodiment, dZ of TX100 PTX However, if the value differs from the nominal value of 1.2 mm assumed in the current Qi standard's MPP, k est A method for calculating with greater accuracy was described. In this embodiment, the dZ of TX100 PTX However, this differs from the nominal value of 1.2mm, and the RX200's dZ PRX However, if it differs from the nominal value of 0.66 mm, k est This section explains how to calculate dZ accurately. PRX The above nominal value of 1.2 mm is the nominal value assumed in the current Qi standard's MPP, and dZ PRX The above nominal value of 0.66 mm is the nominal value assumed in the current Qi standard's MPP. Note that the configuration, operation, and processing in the second embodiment, other than those described below, are the same as or similar to those in the first embodiment, and therefore, their descriptions are omitted.

[0150] In the current Qi standard MPP, the TX100's dZ PTX This is equivalent to 1.2mm, and is the dZ of the RX200. PRX It is assumed that this is equivalent to 0.66 mm. The scaling factor and k described in the first embodiment est The calculation method is also designed under that premise. Therefore, the TX100's dZ PTX The distance is significantly different from 1.2mm, and the RX200's dZ PRX If the distance differs from 0.66 mm by a certain amount or more, the premise is broken, so k est This could potentially make it impossible to calculate accurately.

[0151] Therefore, below, the TX100 dZ PTX The distance is significantly different from 1.2mm, and the RX200's dZ PRX When the distance differs from 0.66 mm by a certain amount or more, k est A method for accurately calculating this will be explained using Figures 12 and 13.

[0152] Figure 12 is a flowchart showing an example of processing by TX100 according to the second embodiment. Figure 13 is a flowchart showing an example of processing by RX200 according to the second embodiment.

[0153] First, the RX200 is mounted on the TX100 (F1201, F1301). Then, the TX100 and RX200 perform the Ping phase processing described above (F1202, F1302).

[0154] Next, the TX100 is the RX200's dZ PRX Send a packet transmission request (F1203) containing information about the above to RX200.

[0155] The RX200 is a successor to the TX100, and the RX200 is a successor to the dZ PRX When a request to send a packet containing information is received (Yes in F1303), proceed to F1304. RX200 receives a packet from TX100, and the RX200's dZ PRX If a request to send a packet containing information about is not received (No in F1303), the process returns to F1303. In F1304, the RX200's dZ PRX A packet containing information related to the above is sent to TX100. This packet may be, for example, a Report[PRX Identification] packet. Alternatively, this packet may be a newly defined packet.

[0156] Here, the dZ PRX Information regarding dZ PRX This is information indicating the distance.

[0157] For example, dZ PRXInformation indicating distance is dZ PRX The distance is such that it is "2.5mm" or "3.0mm", and the specific dZ PRX This is information indicating the distance.

[0158] Alternatively, dZ PRX The information indicating the distance is one of several predetermined distances, dZ PRX This is information indicating the corresponding distance. For example, let's assume that distances of "2.5mm", "3.0mm", and "3.5mm" are predetermined. Also, let's assume that the RX200 sends information "1" to the TX100 when the distance is "2.5mm", information "2" when the distance is "3.0mm", and information "3" when the distance is "3.5mm". And, for example, dZ PRX If the value is "3.0mm", the RX200 will send the information "2" to the TX100.

[0159] Alternatively, dZ PRX The information indicating the distance is the dZ PRX This information indicates whether the value is below a predetermined threshold or within a predetermined range. For example, the RX200 is compared to the TX100 with dZ PRX If it is 3.0mm or more, send the information "1", dZ PRX If it is less than 3.0mm, it sends the information "0". Alternatively, for example, the RX200 sends the information "dZ" to the TX100. PRX If the value is "1.5mm or more but less than 2.0mm", it sends the information "1". Also, for example, the RX200 sends the information "dZ" to the TX100. PRX If the value is "2.0 mm or more, but less than 2.5 mm", it sends the information "2". Also, for example, the RX200 sends the information "dZ" to the TX100. PRX If the value is "2.5mm or more but less than 3.0mm", send the information "3".

[0160] The TX100 is a successor to the RX200, and is a successor to the RX200's dZ. PRX Determine whether or not a packet containing information about dZ has been received (F1204). TX100 receives information from RX200, dZ PRXIf a packet containing information about is received (Yes in F1204), proceed to F1205. TX100 receives information from RX200, dZ PRX If no packet containing information is received (No in F1204), return to F1204.

[0161] In F1205, TX100 is dZ PRX Information regarding (i.e., dZ) PRX Select the intrinsic coefficients (information for calculating or determining the coupling state) related to the coupling state calculation according to the specified parameters. The method for selecting the intrinsic coefficients for TX100 is described below.

[0162] The TX100 selects "dZ PRX The "inherent coefficients related to the calculation of the coupling state according to E" are 0xg and E 1xg Therefore, the eigenfactors that the TX100 is predetermined to hold in the Qi standard are the "dZ" selected by the TX100. PRX This is an intrinsic coefficient related to the calculation of the coupling state according to the RX200. In this embodiment, the dZ PRX The reference power receiving device's dZ PRX = 0.66 mm is different. Therefore, E 0xg and E 1xg Regarding dZ PRX The RX200's dZ PRX It needs to be a coefficient that represents the characteristics of a comparable reference power receiving device.

[0163] TX100 is E 0xg and E 1xg For each of them, the RX200 dZ PRX The corresponding values ​​are stored in memory 106. In other words, the TX100 stores, for example, the following information (1) to (3) (each of which is an example of correspondence information that associates the distance between the receiving coil and the enclosure with information for calculating or determining the coupling state between the transmitting device and the receiving device). (1) dZ PRX E when = 2.5mm 0xg and E 1xg . (2) dZPRX E when = 3.0 mm 0xg and E 1xg . (3) dZ PRX E when = 3.5mm 0xg and E 1xg .

[0164] Therefore, the TX100 receives the dZ from the RX200. PRX Based on the information, the dZ PRX E corresponding to 0xg and E 1xg Select this option.

[0165] Alternatively, the TX100 could, for example, use dZ PRX E when = 2.5mm 0xg and E 1xg And, dZ PRX E when = 3.5mm 0xg and E 1xg The and are stored in memory 106. In other words, TX200 stores correspondence information that associates the distance between the receiving coil and the enclosure with information for calculating or determining the coupling state between the transmitting device and the receiving device. And TX100, dZ PRX E when it is between 2.5mm and 3.5mm 0xg and E 1xg This is calculated using linear interpolation. In other words, for TX100, the horizontal axis is dZ. PRX Let the vertical axis be E 0xg and E 1xg Each of these has a graph (data) or formula calculated or determined by linear interpolation. TX100 receives dZ from RX200. PRX Information regarding (i.e., dZ) PRX E corresponding to ) 0xg and E 1xg The value is calculated and selected from the graph (data) or formula. Note that linear interpolation may be used instead of linear approximation; in this case, dZ PRX Three or more values ​​may be used. Also, N dZ (where N is an integer greater than or equal to 3) PRXWhen the value of is used for interpolation, TX100 uses an N-1 order interpolation polynomial to interpolate the dZ received from RX200. PRX Information regarding (i.e., dZ) PRX Alternatively, you may calculate and select the corresponding eigencoefficients.

[0166] Next, the RX200 is the TX100's dZ PTX Send a request to TX100 to send a packet containing information about (F1305).

[0167] The TX100 is a successor to the RX200, and the TX100's DZ PTX When a request to send a packet containing information is received (Yes in F1206), proceed to F1207. TX100 receives a packet from RX200, and the TX100's dZ PTX If a request to send a packet containing information is not received (No in F1206), the process returns to F1206. In F1207, TX100's dZ PTX Send a packet containing information about the above to the RX200.

[0168] Here, the dZ PTX Information regarding dZ PTX This is information indicating the distance.

[0169] For example, dZ PTX Information indicating distance is dZ PTX The distance is such that it is "2.5mm" or "3.0mm", and the specific dZ PTX This is information indicating the distance.

[0170] Alternatively, dZ PTX The information indicating the distance is one of several predetermined distances, dZ PTX This is information indicating the corresponding distance. For example, let's assume that distances of "2.5mm", "3.0mm", and "3.5mm" are predetermined. Also, let's assume that the TX100 sends information "1" to the RX200 when the distance is "2.5mm", information "2" when the distance is "3.0mm", and information "3" when the distance is "3.5mm". And, for example, dZ PTXIf the value is "3.0mm", the TX100 will send the information "2" to the RX200.

[0171] Alternatively, dZ PTX The information indicating the distance is the dZ PTX This information indicates whether the value is below a predetermined threshold or within a predetermined range. For example, TX100 is dZ for RX200. PTX If it is 3.0mm or more, send the information "1", dZ PTX If it is less than 3.0mm, it sends the information "0". Alternatively, for example, TX100 sends dZ to RX200. PTX If the value is "1.5mm or more but less than 2.0mm", it sends the information "1". Also, for example, TX100 sends the information to RX200, dZ PTX If the value is "2.0 mm or more, but less than 2.5 mm", it sends the information "2". Also, for example, the TX100 sends the information to the RX200, dZ PTX If the value is "2.5mm or more but less than 3.0mm", send the information "3".

[0172] The RX200 is a successor to the TX100, and the dZ PTX Determine whether or not a packet containing information about dZ has been received (F1306). RX200 receives from TX100, dZ PTX If a packet containing information about is received (Yes in F1306), proceed to F1307. RX200 receives information from TX100, dZ PTX If no packet containing information is received (No in F1306), return to F1306.

[0173] In F1307, the RX200 is dZ PTX Information regarding (i.e., dZ) PTX Select the intrinsic coefficients (information for calculating or determining the coupling state) related to the coupling state calculation according to the specified parameters. Here, we will explain how to select the intrinsic coefficients for the RX200.

[0174] The RX200 selects "dZ PTX The "inherent coefficients related to the calculation of the coupling state according to E" are 0gy , E0gg , E 1gy and E 1gg (Therefore, scaling factor α 0rx and α 1rx ) In other words, the eigenfactor in E{a}{b}{c} above, where {b} is g (reference power transmission device), is the "dZ" selected by RX200. PTX This is an intrinsic coefficient related to the calculation of the coupling state according to the TX100. PTX The reference power transmission device's dZ PTX =1.2mm is different. Therefore, E 0gy , E 0gg , E 1gy and E 1gg Regarding dZ PTX TX100 dZ PTX It needs to be a coefficient that represents the characteristics of a comparable reference power transmission device.

[0175] The RX200 is E 0gy , E 0gg , E 1gy and E 1gg For each of them, dZ PTX The corresponding values ​​are stored in memory 208. In other words, the RX200 stores, for example, the following information (1) to (3) (each of which is an example of correspondence information that associates the distance between the power transmission coil and the enclosure with information for calculating or determining the coupling state between the power transmission device and the power receiving device). (1) dZ PTX E when = 2.5mm 0gy , E 0gg , E 1gy and E 1gg . (2) dZ PTX E when = 3.0 mm 0gy , E 0gg , E 1gy and E 1gg . (3) dZ PTX E when = 3.5mm 0gy , E 0gg , E 1gy and E 1gg .

[0176] Therefore, the RX200 receives the dZ from the TX100. PTX Based on the information, the dZ PTX E corresponding to 0gy , E 0gg , E 1gy and E 1gg Select this. Then, RX200 will use the selected eigenfactor E 0gy , E 0gg , E 1gy and E 1gg Therefore, scaling factor α 0rx and α 1rx Calculate and select.

[0177] Alternatively, another method is that the RX200 could, for example, use the dZ PTX E when = 2.5mm 0gy , E 0gg , E 1gy and E 1gg And, dZ PTX E when = 3.5mm 0gy , E 0gg , E 1gy and E 1gg The RX200 stores this information in memory 208. In other words, the RX200 stores correspondence information that associates the distance between the power transmission coil and the enclosure with the information for calculating or determining the coupling state between the power transmission device and the power receiving device. The RX200 then stores dZ PTX E when it is between 2.5mm and 3.5mm 0gy , E 0gg , E 1gy and E 1gg This is calculated using linear interpolation. In other words, for the RX200, the horizontal axis is dZ. PTX Let the vertical axis be E 0gy , E 0gg , E 1gy and E 1gg Each of these has a graph (data) or formula calculated or determined by linear interpolation. The RX200 receives dZ from the TX100. PTX Information regarding (i.e., dZ) PRX E corresponding to ) 0gy , E 0gg , E 1gy and E1gg The RX200 then calculates and selects the eigenfactor E from the graph (data) or formula. 0gy , E 0gg , E 1gy and E 1gg From, α 0rx and α 1rx Calculate and select. Note that linear approximation may be used instead of linear interpolation, in which case dZ PTX Three or more values ​​may be used. Also, N dZ (where N is an integer greater than or equal to 3) PTX When the value of is used for interpolation, the RX200 uses an N-1 order interpolation polynomial to interpolate the dZ received from the TX100. PTX Information regarding (i.e., dZ) PTX Alternatively, you may calculate and select the corresponding eigencoefficients.

[0178] Alternatively, the RX200 is dZ PTX You may also select the scaling factor itself (information for calculating or determining the coupling state) for calculating the coupling state accordingly. The following describes how to select the scaling factor for the RX200.

[0179] The RX200 selects "dZ PTX The scaling factor for calculating the coupling state according to α 0rx and α 1rx That is. The RX200 is α 0rx and α 1rx For each of them, dZ PTX The corresponding values ​​are stored in memory 208. In other words, the RX200 stores, for example, the following information (1) to (3) (where (1) to (3) are examples of correspondence information that associates the distance between the power transmission coil and the enclosure with information for calculating or determining the coupling state between the power transmission device and the power receiving device). (1) dZ PTX α when = 2.5mm 0rx and α 1rx . (2) dZ PTX α when =3.0mm 0rx and α 1rx . (3) dZ PTX α when =3.5mm 0rx and α 1rx .

[0180] Therefore, the RX200 receives the dZ from the TX100. PTX Based on the information, the dZ PTX α corresponding to 0rx and α 1rx Select this option.

[0181] Alternatively, another method is that the RX200 could, for example, use the dZ PTX α when = 2.5mm 0rx and α 1rx And, dZ PTX α when =3.5mm 0rx and α 1rx The RX200 stores this information in memory 208. In other words, the RX200 stores correspondence information that associates the distance between the power transmission coil and the enclosure with the information for calculating or determining the coupling state between the power transmission device and the power receiving device. The RX200 then stores dZ PTX α when it is between 2.5mm and 3.5mm 0rx and α 1rx This is calculated using linear interpolation. In other words, for the RX200, the horizontal axis is dZ. PTX Let the vertical axis be α 0rx and α 1rx Each of these has a graph (data) or formula calculated or determined by linear interpolation. The RX200 receives dZ from the TX100. PTX Information regarding (i.e., dZ) PRX ) corresponds to α 0rx and α 1rx The value is calculated and selected from the graph (data) or formula. Note that linear interpolation may be used instead of linear approximation; in this case, dZ PTX Three or more values ​​may be used. Also, N dZ (where N is an integer greater than or equal to 3) PTX When the value of is used for interpolation, the RX200 uses an N-1 order interpolation polynomial to interpolate the dZ received from the TX100. PTX Information regarding (i.e., dZ) PTXAlternatively, you may calculate and select a scaling factor corresponding to ).

[0182] The following describes another method for selecting the eigenfactors of the RX200. Here, the "dZ" selected by the RX200 is... PTX The "inherent coefficients related to the calculation of the coupling state according to E" are 0gg and E 1gg Therefore, the eigenfactor in the above-mentioned E{a}{b}{c} where {b} is g (reference power transmission device) and {c} is g (reference power receiving device) is the "dZ" selected by RX200. PTX These are "inherent coefficients related to the calculation of the coupling state according to the RX200. 0gg and E 1gg For each of them, dZ PTX +dZ PRX The corresponding value is stored in memory 208. In other words, the RX200 stores, for example, the following information (1) to (4). (1) to (4) are examples of correspondence information that associates the sum of the distance between the transmitting coil and the enclosure and the distance between the receiving coil and the enclosure (or the distance between the transmitting coil and the receiving coil) with information for calculating or determining the coupling state between the power transmitting device and the power receiving device. (1) dZ PTX +dZ PRX E when = 1.86 mm 0gg and E 1gg . (2) dZ PTX +dZ PRX E when = 3.0 mm 0gg and E 1gg . (3) dZ PTX +dZ PRX E when = 3.5mm 0gg and E 1gg . (4) dZ PTX +dZ PRX E when = 4.0 mm 0gg and E 1gg .

[0183] Also, the RX200 is the RX200 dZ PRXAssume that this is already stored in memory 208.

[0184] Therefore, the RX200 receives the dZ from the TX100. PTX Based on the information, dZ PTX +dZ PRX Calculate the dZ PTX +dZ PRX E corresponding to 0gg and E 1gg Select this option.

[0185] Alternatively, another method is that the RX200 could, for example, use the dZ PTX +dZ PRX E when = 1.86 mm 0gg and E 1gg And, dZ PTX +dZ PRX E when = 4.0 mm 0gg and E 1gg The RX200 stores this information in memory 208. In other words, the RX200 stores correspondence information that associates the sum of the distance between the transmitting coil and the enclosure and the distance between the receiving coil and the enclosure (or the distance between the transmitting coil and the receiving coil) with information for calculating or determining the coupling state between the transmitting device and the receiving device. The RX200 then stores dZ PTX +dZ PRX E when it is between 1.86 mm and 4.0 mm 0gg and E 1gg This is calculated using linear interpolation. In other words, for the RX200, the horizontal axis is dZ. PTX +dZ PRX Let the vertical axis be E 0gg and E 1gg Each of these has a graph (data) or formula calculated or determined by linear interpolation. The RX200 receives dZ from the TX100. PTX dZ calculated based on the information provided PTX +dZ PRX E corresponding to 0gg and E 1gg The RX200 then calculates and selects the eigenfactor E from the graph (data) or formula. 0gg and E 1ggAnd E, which was calculated and selected using the method described above. 0gy and E 1gy And from, α 0rx and α 1rx Calculate and select. Note that linear approximation may be used instead of linear interpolation, in which case dZ PTX +dZ PRX Three or more values ​​may be used. Also, N dZ (where N is an integer greater than or equal to 3) PTX +dZ PRX When the value of is used for interpolation, RX200 uses an N-1 order interpolation polynomial to calculate dZ PTX +dZ PRX You may also calculate and select the corresponding eigencoefficients.

[0186] Next, the RX200 uses the scaling factor (α) obtained by the method described above. 0rx (Alpha0 Rx) and α 1rx The RX200 sends a predetermined packet containing information about (Alpha1 Rx) to the TX100 (F1308). This packet is an MPP-Extended Identification Packet (Qi MPP Extended Identification, MPP-XID data packet) as defined by the Qi standard. The RX200 sends the MPP-Extended Identification Packet to the TX100 during the Ping phase or Configuration phase described above. This packet contains the V measured by the RX200. rect This also includes information about [the subject].

[0187] TX100 determines whether or not it has received a scaling factor related to coupling state calculation from RX200 (F1208). If TX100 determines that it has received a scaling factor related to coupling state calculation from RX200 (Yes in F1208), it proceeds to F1209. If TX100 determines that it has not received a scaling factor related to coupling state calculation from RX200 (No in F1208), it returns to F1208.

[0188] In F1209, TX100 calculates the coupling state using the scaling factor for coupling state calculation received from RX200. Then, in F1210, TX100 transmits the calculated coupling state information to RX200. Then, in F1211, TX100 performs control according to the calculated coupling state. "Control according to the calculated coupling state" could mean, for example, that TX100 has multiple resonant capacitors 107 (not shown), and TX100 selects the optimal resonant capacitor 107 from among the multiple resonant capacitors according to the calculated coupling state. Additionally or alternatively, "control according to the calculated coupling state" could mean, for example, that TX100 selects a noise suppression circuit according to the calculated coupling state. Additionally or alternatively, "control according to the calculated coupling state" could mean, for example, that TX100 predicts the power that can be transmitted according to the calculated coupling state. Additionally or alternatively, "control according to the calculated coupling state" may mean, for example, that TX100 selects the optimal parameters for in-band communication according to the calculated coupling state.

[0189] At F1309, RX200 determines whether or not it has received information regarding the coupling state calculated by TX100. If RX200 determines at F1309 that it has received information regarding the coupling state calculated by TX100 (Yes at F1309), it proceeds to F1310. If RX200 determines that it has not received information regarding the coupling state calculated by TX100 (No at F1309), it returns to F1309. At F1310, RX200 performs control according to the calculated coupling state based on the received information. "Control according to the calculated coupling state" may, for example, mean that RX200 has multiple resonant capacitors 211 (not shown), and RX200 selects the optimal resonant capacitor 211 from among the multiple resonant capacitors according to the coupling state. Additionally or alternatively, "control according to the calculated coupling state" may mean, for example, that RX200 selects a noise suppression circuit according to the coupling state. Additionally or alternatively, "control based on calculated coupling state" may mean, for example, that the RX200 predicts the power that can be received based on the coupling state. Additionally or alternatively, "control based on calculated coupling state" may mean, for example, that the RX200 selects the optimal parameters for in-band communication based on the coupling state.

[0190] Figure 17 is a sequence diagram showing an example of processing by TX100 and RX200 according to the second embodiment.

[0191] The RX200 is mounted on the TX100 (S1701, S1702). The TX100 and RX200 perform the Ping phase processing (S1703).

[0192] TX100 is dZ PRX A request to send a packet containing information about dZ is sent to RX200 (S1704). RX200 then sends a request to send a packet containing information about dZ. PRX A packet containing information about dZ is sent to TX100 (S1705). TX100 then... PRX A scaling factor for calculating the coupling state is selected or calculated based on the information provided (S1706).

[0193] The RX200 is dZ PTX A request to send a packet containing information about dZ is sent to TX100 (S1707). TX100 then PTX A packet containing information about dZ is sent to RX200 (S1708). RX200 then... PTX Select or calculate a scaling factor for calculating the coupling state based on the information provided (S1709). RX200 transmits the selected coefficient (scaling factor) for calculating the coupling state to TX100 (S1710).

[0194] TX100 transmits information about the calculated coupling state to RX200 (S1711). TX100 and RX200 then perform control according to the calculated coupling state (S1712).

[0195] By having TX100 and RX200 perform the above control, TX100 can calculate a more accurate coupling state between TX100 and RX200. That is, the dZ of TX100 PTX The reference power transmission device's dZ PTX Unlike (1.2mm), and also unlike the RX200's dZ PRX The reference power receiving device's dZ PRX Even when the size differs from (0.66 mm), it becomes possible to calculate the bonding state with higher accuracy.

[0196] In the embodiment described above, TX100 and RX200 are dZ PTX Information and dZ PRX They exchange information about each other, E 0xg , E 1xg , E 0gy , E 0gg , E 1gy and E 1ggWe have explained how to select appropriate values ​​for all of them. However, it is not necessary to select appropriate values ​​for all of them for TX100 and RX200. TX100 and RX200 may select appropriate values ​​for only some of their eigenfactors using the method described above, and use default values ​​for the remaining eigenfactors without performing the process described above. Even setting only some of the eigenfactors to appropriate values ​​will allow for a more accurate calculation of the coupling state than not performing the process of selecting appropriate values ​​at all. And, in accordance with the highly accurate coupling state, TX100 and RX200 will be able to perform more appropriate control.

[0197] Furthermore, the operations of F1203-F1211 and F1303-F1310 are performed during the Ping phase or Configuration phase.

[0198] Furthermore, the order of operations in the operation flow of TX100 and RX200 is not limited to the examples described above (for example, the examples shown in Figures 12, 13, and 17). In the embodiments described above, RX200 first performs dZ PTX Information is sent to TX100, and TX100 selects or calculates an appropriate scaling factor. Then TX100 PTX Information regarding this is sent to the RX200, and the RX200 selects or calculates an appropriate scaling factor. However, for example, this order may be reversed. That is, the processing order of F1203~F1205 and F1206~F1208 on the TX100 may be swapped, and the processing order of F1303~F1304 and F1305~F1308 on the RX200 may be swapped. In this case, the RX200 will send dZ to the MPP-Extended Identification Packet. PRX The packet may also be sent to the TX100, including information related to the above. The same effect can be obtained with the above operation; that is, it becomes possible to calculate the coupling state with higher accuracy.

[0199] [Third Embodiment] In the first embodiment, dZ of TX100 PTX The reference power transmission device's dZ PTX A method for accurately calculating the coupling state between TX100 and RX200 when it differs from 1.2 mm was described. In the second embodiment, the dZ of TX100 PTX Unlike 1.2mm, and also the RX200's dZ PRX The reference power receiving device's dZ PRX A method for accurately calculating the coupling state between TX100 and RX200 when it differs from 0.66 mm was described. In this embodiment, the threshold for determining the calculated coupling state between TX100 and RX200 is set to the dZ of TX100. PTX A method for making a decision based on this will be explained. Note that the configurations, operations, and processes other than those in the third embodiment described below are the same as or similar to those in the first embodiment, so the explanation of those configurations, operations, and processes will be omitted.

[0200] Similar to the first embodiment, TX100 dZ PTX The reference power transmission device's dZ PTX The case where the value differs from 1.2 mm will be explained using the flowcharts shown in Figures 10 and 11.

[0201] As described in the first embodiment, in F1106, the scaling factor (α 0rx (Alpha0 Rx) and α 1rx A predetermined packet containing information about (Alpha1 Rx)) is sent to TX100. This packet is an MPP-Extended Identification Packet (Qi MPP Extended Identification, MPP-XID data packet) as defined by the Qi standard.

[0202] TX100 compares the calculated coupling state in F1008 with a predetermined threshold. If the calculated coupling state is greater than (or equal to) the predetermined threshold, TX100 determines that it is a strongly coupled state and performs the control appropriate for a strongly coupled state. On the other hand, if the calculated coupling state is less than (or equal to) the predetermined threshold, TX100 determines that it is a weakly coupled state and performs the control appropriate for a weakly coupled state. This threshold is α included in the MPP-Extended Identification Packet mentioned above. k_threshold It is determined based on the information of (Alpha-Kth Rx). α k_threshold This is the ecosystem scaling coefficient used to determine the threshold. The threshold is determined by TX100 relative to a predetermined value. k_threshold It is calculated by multiplying by .

[0203] Here, if a foreign object is introduced between TX100 and RX200, the bond will weaken, making it possible to detect the foreign object depending on the bond state. On the other hand, the bond state between TX100 and RX200 is dZ PTX It changes depending on dZ. PTX The longer the bond, the weaker the bond becomes. PTX The shorter the bond, the stronger the bond. Therefore, the dZ of the TX100 PTX The reference power transmission device's dZ PTX When it is 1.2mm, and the dZ of the TX100 PTX The reference power transmission device's dZ PTX The coupling state between TX100 and RX200 differs depending on whether the value is 1.2 mm or not. More specifically, the coupling state between TX100 and RX200 differs when there is no foreign object and the transmitting and receiving coils are facing each other directly. Therefore, for example, in order to perform foreign object detection according to the calculated coupling state, it is necessary to correct the threshold value mentioned above. Also, in order to perform predetermined controls other than foreign object detection according to the calculated coupling state, it is necessary to correct the threshold value mentioned above.

[0204] In other words, the RX200 receives the dZ from the TX100 in the F1104.PTX Information (dZ PTX α (value) k_threshold The decision is made. The RX200 is the first dZ PTX For the value of , the first α k_threshold Determined, the first dZ PTX The second dZ is longer than PTX For the value of , the first α k_threshold A second alpha that is smaller than k_threshold To decide.

[0205] And the RX200, in F1106, determined the α k_threshold Send the MPP-Extended Identification Packet containing the above to TX100.

[0206] TX100 is, in F1005, α k_threshold The TX100 receives an MPP-Extended Identification Packet containing the α at F1008. k_threshold The threshold is calculated by multiplying by .

[0207] By controlling TX100 and RX200 as described above, TX100 can appropriately set a threshold value for the calculated coupling state to determine whether to execute a predetermined control.

[0208] Next, we will explain the case where the RX200 calculates the coupling state and performs predetermined control based on a predetermined threshold. The Qi standard states that the RX200 calculates an index called Gain and performs control by comparing this Gain with a predetermined threshold.

[0209] In this embodiment, the predetermined threshold is set to the dZ of TX100. PTX The method for making this determination will be explained using Figures 14 and 15.

[0210] Figure 14 is a flowchart showing an example of processing for TX100 according to the third embodiment, and Figure 15 is a flowchart showing an example of processing for RX200 according to the third embodiment.

[0211] First, the RX200 is mounted on the TX100 (F1401, F1501). Then, the TX100 and RX200 perform the Ping phase processing described above (F1402, F1502). Finally, the TX100 and RX200 perform the Configuration phase processing described above (F1403, F1503).

[0212] Next, the RX200 disconnects its load (battery, etc.) (F1504). Alternatively, the RX200 controls the load so that only a small current of 50mA or less flows through it (F1504).

[0213] Next, RX200 sends a GET_Inverter Voltage packet to TX100 (F1505). The GET_Inverter Voltage packet is a GET data packet that notifies TX100 that RX200 is requesting information about the voltage of TX100's inverter. This GET data packet has a PRx Get Request Type of "PTx Inverter Voltage".

[0214] TX100 determines whether or not it has received a GET_Inverter Voltage packet from RX200 (F1404). If TX100 determines that it has received a GET_Inverter Voltage packet (Yes in F1404), it proceeds to F1405. If TX100 determines that it has not received a GET_Inverter Voltage packet (No in F1404), it returns to F1404.

[0215] In F1405, TX100 measures the voltage of the inverter of TX100, and the measured voltage of the inverter of TX100 (V INVSend an Inverter Voltage packet containing information about the inverter voltage (V) of the TX100 to the RX200. INV ) refers to the input voltage that is input to the inverter of the TX100, or the output voltage that is output from the inverter of the TX100.

[0216] RX200 determines whether or not it has received an Inverter Voltage packet from TX100 (F1506). If RX200 determines that it has received an Inverter Voltage packet (Yes in F1506), it proceeds to F1507. If RX200 determines that it has not received an Inverter Voltage packet (No in F1506), it returns to F1506.

[0217] In F1507, RX200 is the output voltage after rectification in the rectifier circuit of RX200, V rect Measure the V rect Then, the first Gain(G1) is calculated from the voltage information of the TX100 inverter received from the TX100. The first Gain(G1) is calculated using the following formula. G1=V rect / V INV

[0218] G1 is the V when the load on the RX200 is disconnected. rect and V INV This is the Gain calculated from the above. Gain is an indicator (coupling state indicator) that represents the coupling state between TX100 and RX200.

[0219] Next, connect the load (battery, etc.) to the RX200 (F1508).

[0220] Next, RX200 sends a GET_Inverter Voltage packet to TX100 (F1509).

[0221] TX100 determines whether or not it has received a GET_Inverter Voltage packet from RX200 (F1406). If TX100 determines that it has received a GET_Inverter Voltage packet (Yes in F1406), it proceeds to F1407. If TX100 determines that it has not received a GET_Inverter Voltage packet (No in F1406), it returns to F1406.

[0222] In F1407, TX100 measures the voltage of the inverter of TX100, and the measured voltage of the inverter of TX100 (V INV Send an Inverter Voltage packet containing the information of ) to the RX200.

[0223] RX200 determines whether or not it has received an Inverter Voltage packet from TX200 (F1510). If RX200 determines that it has received an Inverter Voltage packet (Yes in F1510), it proceeds to F1511. If RX200 determines that it has not received an Inverter Voltage packet (No in F1510), it returns to F1510.

[0224] In F1511, RX200 is the output voltage after rectification in the rectifier circuit of RX200, V rect Measure the V rect Then, the second Gain(G2) is calculated from the voltage information of the TX100 inverter received from the TX100. The second Gain(G2) is calculated using the following formula. G2=V rect / V INV

[0225] G2 is the V when the RX200 is connected to a load. rect and V INV This is the Gain calculated from the above.

[0226] Next, the RX200 multiplies the calculated G1 and G2 to calculate G1*G2 (G1 × G2) (F1512). Then, the RX200 determines whether the calculated G1*G2 is greater than or equal to the first threshold (or equal to or greater than the first threshold) (F1513).

[0227] The RX200 determines that G1*G2 is greater than (or equal to or greater than) the first threshold (Yes in F1513), V rect_target The first V rect_target It was decided that P r_max The first P r_max It is decided to be (F1514). Here, V rect_target This refers to the target V in loop control. rect This is the value of P. r_max This refers to the maximum power value that the RX200 can draw, after rectification in the RX200's rectifier circuit. In other words, it is the maximum power value that the RX200 can receive.

[0228] If the RX200 determines that G1*G2 is less than or equal to the first threshold (No in F1513), it proceeds to F1515. Then, the RX200 determines whether G1*G2 is greater than or equal to the second threshold (F1515).

[0229] The RX200, if it determines that G1*G2 is greater than (or equal to or greater than) the second threshold (Yes in F1515), V rect_target The second V rect_target It was decided that P r_max to the second P r_max Decision made (F1516).

[0230] If the RX200 determines that G1*G2 is less than or equal to the second threshold (or less than the second threshold) (F1515 indicates No), it proceeds to F1517. Then, the RX200 determines whether G1*G2 is greater than or equal to the third threshold (or greater than or equal to the third threshold) (F1517).

[0231] The RX200, if it determines that G1*G2 is greater than (or equal to or greater than) the third threshold (Yes in F1517), V rect_target to the third V rect_target It was decided that P r_max to the third P r_max Decision made (F1518).

[0232] The RX200 determines that G1*G2 is below the third threshold (or less than the third threshold) (No in F1517), V rect_target to the fourth V rect_target It was decided that P r_max to the fourth P r_max Decision made (F1519).

[0233] The relationship between the thresholds mentioned above is as follows: First threshold > Second threshold > Third threshold

[0234] Also, V rect_target The relationship between the values ​​is as follows: First V rect_target = Second V rect_target The third V rect_target = Fourth V rect_target First V rect_target >The Third V rect_target

[0235] Also, P r_max The relationship between the values ​​is as follows: First P r_max >Second P r_max >The third P r_max ≥ Fourth P r_max

[0236] In other words, the larger the value of G1*G2, which is an indicator of the coupling state between TX100 and RX200, the higher P r_max The value of is controlled to increase, and V accordingly. rect_target The value of this value is also controlled.

[0237] Note that in the above, threshold, V rect_target and P r_maxThe numbers are 3, 4, and 4, respectively, but are not limited to these numbers as long as the relationships between these values ​​are appropriately set.

[0238] Similar to the first embodiment, TX100 dZ PTX The reference power transmission device's dZ PTX The method for setting the first, second, and third thresholds described above when the value differs from 1.2 mm will be explained.

[0239] The RX200 is the TX100's dZ PTX The first dZ PTX In that case, the first threshold is set to A, the second threshold to B, and the third threshold to C.

[0240] And the RX200 is the TX100's dZ PTX The first dZ PTX The second dZ is longer than PTX In that case, the first threshold is set to D, the second threshold to E, and the third threshold to F.

[0241] Here, the thresholds A, B, C, D, E, F have the relationships A>D, B>E, and C>F.

[0242] Gain(G1, G2, G1*G2) is an index used to determine, based on the coupling state, whether the RX200, which is mounted on the TX100, is likely to be within a predetermined range. If the RX200 moves from outside the predetermined range to within the predetermined range, a sudden load change will occur, and the overvoltage protection will be activated. Therefore, if it is determined in advance that there is a high probability that the RX200 is outside the predetermined range based on the Gain, V rect_target YaP r_max By setting it lower, wireless power transmission can be performed more safely. However, dZ PTX If the TX100 is longer than a predetermined value, the Gain will fall below the threshold even though the TX100 and RX200 are facing each other directly, and V rect_target YaP r_maxIt is anticipated that the threshold value may be set too low. In this embodiment, by controlling the threshold value as described above, it is possible to mitigate or prevent such unintended settings.

[0243] Figure 18 is a sequence diagram showing an example of processing by TX100 and RX200 according to the third embodiment.

[0244] The RX200 is mounted on the TX100 (S1801, S1802). The TX100 and RX200 perform the Ping phase processing (S1803). The TX100 and RX200 perform the Configuration phase processing (S1804).

[0245] RX200 disconnects its load (S1805). RX200 sends a GET_Inverter Voltage packet to TX100 (S1806). TX100 sends an Inverter Voltage packet to RX200 (S1807). RX200 calculates G1 (S1808).

[0246] RX200 connects its load (S1809). RX200 sends a GET_Inverter Voltage packet to TX100 (S1810). TX100 sends an Inverter Voltage packet to RX200 (S1811). RX200 calculates G2 (S1812).

[0247] The RX200 calculates G1*G2 (S1813). The RX200 compares G1*G2 with the first threshold and makes a determination (S1814). The RX200 compares G1*G2 with the second threshold and makes a determination (S1815). The RX200 compares G1*G2 with the third threshold and makes a determination (S1816). The RX200 then performs V rect_target and P r_max Decide (S1817).

[0248] As described above, the threshold for determining the coupling state between the calculated TX100 and RX200 is the dZ of the TX100.PTX By making decisions based on this, it becomes possible to perform wireless power transmission more effectively.

[0249] In this embodiment, the dZ of TX100 PTX Accordingly, the threshold for making a predetermined determination based on the coupling state was changed. Similar to the "coupling state", the dZ of TX100 PTX There are other physical quantities that change in response to this. For example, the foreign object detection method described above using the Power Loss method is based on the difference between the transmitted power and the received power, but this "difference between the transmitted power and the received power" is also related to the TX100's dZ PTX It changes accordingly. This is because the power transmission efficiency decreases as the distance between the transmitting coil and the receiving coil increases. Therefore, the threshold for foreign object detection using the Power Loss method described above is also the dZ of TX100, as explained in this embodiment. PTX It is changed accordingly. In other words, in foreign object detection using the Power Loss method, the dZ of the TX100 PTX If the first value is set, a first threshold is set for determining the presence or absence of foreign matter in relation to the "difference between transmitted power and received power". Then, the dZ of TX100 PTX If the second value is longer than the first value, a second threshold greater than the first threshold for determining the presence or absence of foreign matter is set for the "difference between transmitted power and received power". As described above, the threshold for determining the presence or absence of foreign matter between TX100 and RX200 is set for TX100's dZ PTX By making decisions based on this, it becomes possible to perform wireless power transmission more effectively.

[0250] Using a similar approach, the TX100's dZ PTX For the threshold set for a physical quantity that changes in accordance with this, the dZ of TX100 is set using the method described in this embodiment. PTX By making decisions based on this, it becomes possible to properly execute wireless power transmission.

[0251] [Fourth Embodiment] In the third embodiment, the threshold for determining the coupling state between the calculated TX100 and RX200 is the dZ of TX100. PTX A method for determining based on this was described. In this embodiment, the threshold for determining the coupling state between the calculated TX100 and RX200 is the dZ of TX100. PTX and RX200 dZ PRX A method for making a decision based on this will be explained. Note that the configurations, operations, and processes other than those in the fourth embodiment described below are the same as or similar to those in the first embodiment, so the explanation of those configurations, operations, and processes will be omitted.

[0252] Similar to the second embodiment, the dZ of TX100 PTX Unlike 1.2mm, and also the RX200's dZ PRX The case where the value differs from 0.66 mm will be explained using the flowcharts shown in Figures 12 and 13.

[0253] As described in the second embodiment, in F1307, the scaling factor (α 0rx (Alpha0 Rx) and α 1rx A predetermined packet containing information about (Alpha1 Rx)) is sent to TX100. This packet is an MPP-Extended Identification Packet (Qi MPP Extended Identification, MPP-XID data packet) as defined by the Qi standard.

[0254] TX100 compares the calculated coupling state in F1211 with a predetermined threshold. If the calculated coupling state is greater than (or equal to) the predetermined threshold, TX100 determines that it is a strongly coupled state and performs the control appropriate for a strongly coupled state. On the other hand, if the calculated coupling state is less than (or equal to) the predetermined threshold, TX100 determines that it is a weakly coupled state and performs the control appropriate for a weakly coupled state. This threshold is α included in the MPP-Extended Identification Packet mentioned above.k_threshold It is determined based on the information of (Alpha-Kth Rx). α k_threshold This is the ecosystem scaling coefficient used to determine the threshold. The threshold is determined by TX100 relative to a predetermined value. k_threshold It is calculated by multiplying by .

[0255] Here, if a foreign object is introduced between TX100 and RX200, the bond will weaken, making it possible to detect the foreign object depending on the bond state. On the other hand, the bond state between TX100 and RX200 is dZ PTX and dZ PRX It changes depending on dZ. PTX +dZ PRX The longer the bond, the weaker the bond becomes. PTX +dZ PRX The shorter the bond, the stronger the coupling. Therefore, the coupling state between TX100 and RX200 will be different in case (1) and case (2) below. (1) TX100 dZ PTX The reference power transmission device's dZ PTX It is 1.2mm, and the RX200's dZ PRX The reference power receiving device's dZ PRX If it is 0.66 mm. (2) TX100 dZ PTX The reference power transmission device's dZ PTX Unlike the 1.2mm and / or the RX200's dZ PRX The reference power receiving device's dZ PRX If it is different from 0.66 mm. More specifically, the coupling state between TX100 and RX200 differs when there are no foreign objects present and the transmitting and receiving coils are facing each other directly. Therefore, in order to perform foreign object detection according to the calculated coupling state, it is necessary to correct the threshold value mentioned above.

[0256] In other words, RX200 is the dZ calculated in F1307, as described in the second embodiment. PTX +dZ PRX αk_threshold The decision is made. The RX200 is the first dZ PTX +dZ PRX For the value of , the third α k_threshold This will be decided. Also, the RX200 is the first dZ PTX +dZ PRX The second dZ is longer than PTX +dZ PRX For the value of , the third α k_threshold A fourth alpha smaller than k_threshold To decide.

[0257] And the RX200, in F1308, determined the α k_threshold Send the MPP-Extended Identification Packet containing the above to TX100.

[0258] TX100 is α in F1208. k_threshold The TX100 receives an MPP-Extended Identification Packet containing the α at F1211. k_threshold The threshold is calculated by multiplying by .

[0259] By controlling TX100 and RX200 as described above, TX100 can appropriately set a threshold value for the calculated coupling state to determine whether to execute a predetermined control.

[0260] Next, we will explain the case where the RX200 calculates the coupling state and performs predetermined control based on a predetermined threshold. The Qi standard states that the RX200 calculates an index called Gain and performs control by comparing this Gain with a predetermined threshold.

[0261] In this embodiment, the predetermined threshold is set to the dZ of TX100. PTX and RX200 dZ PRXThe method for determining the appropriate behavior will be explained. In this embodiment, TX100 performs the same operation as in the flowchart shown in Figure 14 described in the third embodiment. Also, in this embodiment, RX200 performs the same operation as in the flowchart shown in Figure 15 described in the third embodiment. Therefore, the explanation of the flow in which RX200 calculates the coupling state and performs predetermined control based on predetermined thresholds will be omitted.

[0262] In this embodiment as well, the relationship between the first threshold shown at F1513 in Figure 15, the second threshold shown at F1515, and the third threshold shown at F1517 is as follows. First threshold > Second threshold > Third threshold

[0263] Also, V described in F1516, F1518 and F1519 rect_target The relationship between the values ​​is as follows. First V rect_target = Second V rect_target The third V rect_target = Fourth V rect_target First V rect_target >The Third V rect_target

[0264] Also, P described in F1514, F1516, F1518 and F1519 r_max The relationship between the values ​​is as follows. First P r_max >Second P r_max >The third P r_max ≥ Fourth P r_max

[0265] In other words, the larger the value of G1*G2, which is an indicator of the coupling state between TX100 and RX200, the higher P r_max The value of is controlled to increase, and V accordingly. rect_target The value of this value is also controlled.

[0266] Note that in the above, threshold, V rect_target and P r_maxThe numbers are 3, 4, and 4, respectively, but are not limited to these numbers as long as the relationships between these values ​​are appropriately set.

[0267] Similar to the second embodiment, the dZ of TX100 PTX Unlike 1.2mm, and also the RX200's dZ PRX The method for setting the first, second, and third thresholds described above when the value differs from 0.66 mm will be explained below.

[0268] The RX200 is dZ PTX +dZ PRX The first dZ PTX +dZ PRX In that case, the first threshold is set to G, the second threshold to H, and the third threshold to I.

[0269] And the RX200 is dZ PTX +dZ PRX The first dZ PTX +dZ PRX The second dZ is longer than PTX +dZ PRX In that case, the first threshold is set to J, the second threshold to K, and the third threshold to L.

[0270] Here, the thresholds G, H, I, J, K, L have the relationships G>J, H>K, and I>L.

[0271] Gain(G1, G2, G1*G2) is an index used to determine, based on the coupling state, whether the RX200, which is mounted on the TX100, is likely to be within a predetermined range. If the RX200 moves from outside the predetermined range to within the predetermined range, a sudden load change will occur, and the overvoltage protection will be activated. Therefore, if it is determined in advance that there is a high probability that the RX200 is outside the predetermined range based on Gain, V rect_target YaP r_max By setting it lower, wireless power transmission can be performed more safely. However, dZ PTX +dZ PRXIf the interval is longer than a predetermined value, the gain will fall below the threshold even though the TX100 and RX200 are facing each other, and V rect_target YaP r_max It is anticipated that the threshold value may be set too low. In this embodiment, by controlling the threshold value as described above, it is possible to mitigate or prevent such unintended settings.

[0272] As described above, the threshold for determining the coupling state between the calculated TX100 and RX200 is dZ PTX +dZ PRX By making decisions based on this, it becomes possible to perform wireless power transmission more effectively.

[0273] In this embodiment, the dZ of TX100 PTX and RX200 dZ PRX dZ is the sum of the above. PTX +dZ PRX Accordingly, the threshold for making a predetermined determination based on the coupling state was changed. Similar to the "coupling state", dZ PTX +dZ PRX There are other physical quantities that change in response to dZ. For example, the foreign object detection method described above is based on the difference between the transmitted power and the received power, but this "difference between the transmitted power and the received power" is also dZ. PTX +dZ PRX It changes accordingly. This is because the power transmission efficiency decreases as the distance between the transmitting coil and the receiving coil increases. Therefore, the threshold for foreign object detection using the Power Loss method described above is also dZ, as explained in this embodiment. PTX +dZ PRX It is changed accordingly. In other words, in foreign object detection using the Power Loss method, dZ PTX +dZ PRX If the first value is set, a first threshold is set for determining the presence or absence of foreign matter in relation to the "difference between transmitted power and received power". Then, dZ PTX +dZ PRXIf the second value is longer than the first value, a second threshold greater than the first threshold for determining the presence or absence of foreign matter is set for the "difference between transmitted power and received power". As described above, the threshold for determining the presence or absence of foreign matter between TX100 and RX200 is set to dZ PTX +dZ PRX By making decisions based on this, it becomes possible to perform wireless power transmission more effectively.

[0274] Using a similar approach, dZ PTX +dZ PRX For the threshold set for a physical quantity that changes in response to dZ, the method described in this embodiment is used. PTX +dZ PRX By making decisions based on this, it becomes possible to properly execute wireless power transmission.

[0275] [Other embodiments] Some (or all) of the configurations in the above embodiments may be replaced with other configurations that perform similar functions, or omitted, and other configurations may be added. Furthermore, it is not limited to the WPC standard and can be applied to various standards.

[0276] Furthermore, for example, the receiving device may possess some or all of the functions of the power transmission device (see, for example, Figure 6). Alternatively, the receiving device may perform some or all of the processes that the power transmission device should perform (see, for example, Figures 7, 10, 12, and 14).

[0277] Furthermore, the configurations in the above-described embodiment may be combined as appropriate. Also, in the above embodiment, the dZ of TX100 PTX The reference power transmission device's dZ PTX It was stated that even when the value differs from 1.2 mm, it is possible to calculate the coupling state of the TX100 and RX200 with higher accuracy. Furthermore, the dZ of the TX100 PTX The reference power transmission device's dZ PTX Unlike (1.2mm), and also unlike the RX200's dZ PRX The reference power receiving device's dZ PRXIt was stated that high-precision calculation is possible even when it differs from (0.66 mm). The method described in the above embodiment is dZ PTX , or dZ PTX and dZ PRX This method can be applied to physical quantities other than those used to calculate the coupling state between TX100 and RX200, whose characteristics change depending on the distance between them.

[0278] Furthermore, the power transmission and receiving devices may be, for example, image input devices such as imaging devices (still cameras, video cameras, etc.) or scanners, or image output devices such as printers, copiers, or projectors. In addition, the power transmission and receiving devices may be storage devices such as hard disk drives or memory devices, or information processing devices such as personal computers (PCs), smartphones, or tablet devices.

[0279] Furthermore, the power receiving device in this disclosure may also be an information terminal device. For example, an information terminal device has a display unit that displays information to the user and is supplied with power received from a power receiving antenna. The power received from the power receiving antenna is stored in a power storage unit (battery), and power is supplied to the display unit from the battery. In this case, the power receiving device may also have a communication unit that communicates with other devices different from the power transmitting device. The communication unit may support communication standards such as NFC communication or fifth-generation mobile communication systems (5G).

[0280] Furthermore, the power receiving device in this disclosure may be a vehicle such as an automobile. For example, an automobile that is a power receiving device may receive power from a charger (power transmission device) via a power transmission antenna installed in a parking lot. Alternatively, an automobile that is a power receiving device may receive power from a charger (power transmission device) via a power transmission antenna embedded in the road. Such an automobile supplies the received power to a battery. The power from the battery may be supplied to a drive unit (motor, electric unit) that drives the wheels, or it may be used to drive sensors used for driving assistance or a communication unit that communicates with external devices. In other words, in this case, the power receiving device may have a battery, motors and sensors that are driven using the received power, and a communication unit that communicates with devices other than the power transmission device, in addition to the wheels. Furthermore, the power receiving device may have a compartment for accommodating people. For example, sensors may be used to measure the distance between vehicles or the distance to other obstacles. The communication unit may be compatible with, for example, the Global Positioning System (Global Positioning Satellite, GPS). Furthermore, the communication unit may support communication standards such as the fifth-generation mobile communication system (5G). Also, the vehicle may be a bicycle or a motorcycle.

[0281] Furthermore, the power receiving device in this disclosure may be a power tool, a home appliance, or the like. These power receiving devices may have a battery, as well as a motor driven by the power received from the battery. These devices may also have a notification means for notifying the remaining battery level, etc. These devices may also have a communication unit that communicates with other devices different from the power transmitting device. The communication unit may support communication standards such as NFC or fifth-generation mobile communication systems (5G).

[0282] Furthermore, the power transmission device in this disclosure may also be an in-vehicle charger that transmits power to portable information terminal devices such as smartphones and tablets that support wireless power transmission within a vehicle. Such an in-vehicle charger may be installed anywhere in the vehicle. For example, the in-vehicle charger may be installed on the vehicle's console, on the instrument panel (dashboard), between passenger seats, on the ceiling, or on the door. However, it is preferable not to install it in a location that would interfere with driving. In addition, although the power transmission device has been described using the example of an in-vehicle charger, such chargers are not limited to those installed in vehicles, but may also be installed in transport vehicles such as trains, airplanes, and ships. In this case, the charger may also be installed between passenger seats, on the ceiling, or on the door.

[0283] Alternatively, a vehicle such as an automobile equipped with an on-board charger may also serve as a power transmission device. In this case, the power transmission device has wheels and a battery, and uses the power from the battery to supply power to the power receiving device via a power transmission circuit and a power transmission antenna.

[0284] This disclosure can also be implemented by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be implemented by a circuit (e.g., an ASIC) that implements one or more functions.

[0285] Furthermore, some of the processes described in this disclosure with reference to the flowchart may be implemented in hardware. For example, a dedicated circuit can be automatically generated on the FPGA from a program to implement each step by using a predetermined compiler. Alternatively, a Gate Array circuit may be formed in the same way as the FPGA and implemented in hardware.

[0286] Furthermore, the following additional information is disclosed regarding the above embodiments.

[0287] [Note 1] A power transmission device that wirelessly transmits power to a power receiving device, Transmission coil and The enclosure containing the aforementioned power transmission coil, A transmitting means for transmitting first information regarding the distance between the power transmission coil and the enclosure to the power receiving device, A receiving means that receives a second piece of information corresponding to the first piece of information from the power receiving device, Based on the second piece of information, a determination means for determining the coupling state, A power transmission device characterized by having the following features.

[0288] [Note 2] The receiving means receives third information from the power receiving device regarding the distance between the power receiving coil of the power receiving device and the enclosure of the power receiving device that encloses the power receiving coil. The aforementioned power transmission device is Selection means for selecting a fourth piece of information corresponding to the third piece of information. It further possesses, The power transmission device according to Appendix 1, characterized in that the determination means determines the coupling state based on the second information and the fourth information.

[0289] [Note 3] The power transmission device according to Appendix 2, characterized in that the selection means selects the fourth information corresponding to the third information using correspondence information which associates the distance between the power receiving coil and the enclosure with information for determining the coupling state between the power transmission device and the power receiving device.

[0290] [Note 4] The aforementioned third piece of information is included in the aforementioned correspondence information, The power transmission device according to Appendix 3, characterized in that the selection means selects as the fourth piece of information information for determining the coupling state between the power transmission device and the power receiving device, which is associated with the third piece of information in the correspondence information.

[0291] [Note 5] The aforementioned third piece of information is not included in the aforementioned correspondence information. The power transmission device according to Appendix 3, characterized in that the selection means selects the fourth information corresponding to the third information using a graph or calculation formula determined from the correspondence information.

[0292] [Note 6] The power transmission device according to any one of the appendices 1 to 5, characterized in that the transmitting means transmits a fifth piece of information relating to the determined coupling state to the power receiving device.

[0293] [Note 7] Control means for executing control according to the aforementioned coupling state A power transmission device according to any one of the appendices 1 to 6, further comprising the above.

[0294] [Note 8] A power receiving device that receives power wirelessly from a power transmission device, A receiving means for receiving first information from the power transmission device regarding the distance between a power transmission coil in the power transmission device and an enclosure in the power transmission device that encloses the power transmission coil, A transmission means for transmitting to the power transmission device a second piece of information corresponding to the first piece of information, which the power transmission device uses to determine the coupling state between the power transmission device and the power receiving device. A power receiving device characterized by having the following features.

[0295] [Note 9] The power receiving coil and The enclosure containing the aforementioned power receiving coil, It further possesses, The power receiving device according to Appendix 8, characterized in that the transmitting means transmits third information relating to the distance between the power receiving coil and the enclosure enclosing the power receiving coil to the power transmitting device.

[0296] [Note 10] The receiving means receives a fourth piece of information relating to the first voltage of the power transmission device from the power transmission device. The power receiving device is A measuring means for measuring the second voltage of the power receiving device, A determination means for determining a coupling state index between the power transmission device and the power receiving device, which includes a first coupling state index when the load of the power receiving device is disconnected and a second coupling state index when the load is connected, based on the first voltage and the second voltage indicated by the fourth information, A modification means that modifies a threshold value compared with the product of the first coupling state index and the second coupling state index according to the first information, The power receiving device according to Appendix 9, further characterized by having the following:

[0297] [Note 11] The power receiving device according to Appendix 10, characterized in that the modification means changes the threshold according to the first information and the third information.

[0298] [Note 12] A selection means that selects the second piece of information according to the first piece of information using correspondence information that associates the distance between the power transmission coil and the enclosure with information for determining the coupling state between the power transmission device and the power receiving device. A power receiving device according to any one of the appendices 8 to 11, further comprising the above.

[0299] [Note 13] The aforementioned first information is included in the aforementioned correspondence information, The power receiving device according to Appendix 12, characterized in that the selection means selects as the second information information information for determining the coupling state between the power transmission device and the power receiving device that is associated with the first information in the correspondence information.

[0300] [Note 14] The aforementioned first information is not included in the aforementioned correspondence information, The power receiving device according to Appendix 12, characterized in that the selection means selects the second information corresponding to the first information using a graph or calculation formula determined from the correspondence information.

[0301] [Note 15] The power receiving device according to any one of appendices 8 to 14, characterized in that the receiving means receives a fifth piece of information relating to the coupling state from the power transmitting device.

[0302] [Note 16] Control means for executing control according to the coupling state indicated by the fifth piece of information. The power receiving device according to Appendix 15, further characterized by having the following:

[0303] [Note 17] A method used by a power transmission device to wirelessly transmit power to a power receiving device, A step of transmitting first information relating to the distance between a power transmission coil of the power transmission device and an enclosure of the power transmission device that encloses the power transmission coil to the power receiving device, A step of receiving a second piece of information corresponding to the first piece of information from the power receiving device, A step of determining the bonding state based on the second piece of information, A method characterized by having the following:

[0304] [Note 18] A method used by a power receiving device that receives power wirelessly from a power transmission device, A step of receiving first information from the power transmission device regarding the distance between a power transmission coil in the power transmission device and an enclosure in the power transmission device that encloses the power transmission coil, A step of transmitting to the power transmission device a second piece of information corresponding to the first piece of information, which the power transmission device uses to determine the coupling state between the power transmission device and the power receiving device, A method characterized by having the following:

[0305] [Note 19] A program that causes a computer to perform the actions described in Appendix 17 or 18. [Explanation of symbols]

[0306] 100: Power transmission equipment 101, 201: Control Unit 103: Power Transmission Section 105: Power transmission antenna 200: Power receiving device 203: Power receiving section 205: Receiving antenna 303:Measurement part 304: Settings Section 305: State detection unit

Claims

1. A power transmission device that wirelessly transmits power to a power receiving device, Transmission coil and The enclosure containing the aforementioned power transmission coil, A transmitting means for transmitting first information regarding the distance between the power transmission coil and the enclosure to the power receiving device, A receiving means that receives a second piece of information corresponding to the first piece of information from the power receiving device, Based on the second piece of information, a determination means for determining the coupling state, A power transmission device characterized by having the following features.

2. The receiving means receives third information from the power receiving device regarding the distance between the power receiving coil of the power receiving device and the enclosure of the power receiving device that encloses the power receiving coil. The aforementioned power transmission device is Selection means for selecting a fourth piece of information corresponding to the third piece of information. It further possesses, The power transmission device according to claim 1, characterized in that the determination means determines the coupling state based on the second information and the fourth information.

3. The power transmission device according to claim 2, characterized in that the selection means selects the fourth information corresponding to the third information using correspondence information which associates the distance between the power receiving coil and the enclosure with information for determining the coupling state between the power transmission device and the power receiving device.

4. The aforementioned third piece of information is included in the aforementioned correspondence information, The power transmission device according to claim 3, characterized in that the selection means selects as the fourth piece of information information for determining the coupling state between the power transmission device and the power receiving device, which is associated with the third piece of information in the correspondence information.

5. The aforementioned third piece of information is not included in the aforementioned correspondence information. The power transmission device according to claim 3, characterized in that the selection means selects the fourth information corresponding to the third information using a graph or calculation formula determined from the correspondence information.

6. The power transmission device according to claim 1, characterized in that the transmitting means transmits a fifth piece of information relating to the determined coupling state to the power receiving device.

7. Control means for executing control according to the aforementioned coupling state The power transmission device according to claim 1, further comprising the following:

8. A power receiving device that receives power wirelessly from a power transmission device, A receiving means for receiving first information from the power transmission device regarding the distance between a power transmission coil in the power transmission device and an enclosure in the power transmission device that encloses the power transmission coil, A transmission means for transmitting to the power transmission device a second piece of information corresponding to the first piece of information, which the power transmission device uses to determine the coupling state between the power transmission device and the power receiving device. A power receiving device characterized by having the following features.

9. The power receiving coil and The enclosure containing the aforementioned power receiving coil, It further possesses, The power receiving device according to claim 8, characterized in that the transmitting means transmits third information relating to the distance between the power receiving coil and the enclosure enclosing the power receiving coil to the power transmitting device.

10. The receiving means receives a fourth piece of information relating to the first voltage of the power transmission device from the power transmission device. The power receiving device is A measuring means for measuring the second voltage of the power receiving device, A determination means for determining a coupling state index between the power transmission device and the power receiving device, which includes a first coupling state index when the load of the power receiving device is disconnected and a second coupling state index when the load is connected, based on the first voltage and the second voltage indicated by the fourth information, A modification means that modifies a threshold value compared with the product of the first coupling state index and the second coupling state index according to the first information, The power receiving device according to claim 9, further comprising:

11. The power receiving device according to claim 10, characterized in that the modification means changes the threshold according to the first information and the third information.

12. A selection means that selects the second piece of information according to the first piece of information using correspondence information that associates the distance between the power transmission coil and the enclosure with information for determining the coupling state between the power transmission device and the power receiving device. The power receiving device according to claim 8, further comprising:

13. The aforementioned first information is included in the aforementioned correspondence information, The power receiving device according to claim 12, characterized in that the selection means selects as the second information information information for determining the coupling state between the power transmission device and the power receiving device that is associated with the first information in the association information.

14. The aforementioned first information is not included in the aforementioned correspondence information, The power receiving device according to claim 12, characterized in that the selection means selects the second information corresponding to the first information using a graph or calculation formula determined from the correspondence information.

15. The power receiving device according to claim 8, characterized in that the receiving means receives a fifth piece of information relating to the coupling state from the power transmitting device.

16. Control means for executing control according to the coupling state indicated by the fifth piece of information. The power receiving device according to claim 15, further comprising the above.

17. A method used by a power transmission device to wirelessly transmit power to a power receiving device, A step of transmitting first information relating to the distance between a power transmission coil of the power transmission device and an enclosure of the power transmission device that encloses the power transmission coil to the power receiving device, A step of receiving a second piece of information corresponding to the first piece of information from the power receiving device, A step of determining the bonding state based on the second piece of information, A method characterized by having the following:

18. A method used by a power receiving device that receives power wirelessly from a power transmission device, A step of receiving first information from the power transmission device regarding the distance between a power transmission coil in the power transmission device and an enclosure in the power transmission device that encloses the power transmission coil, A step of transmitting to the power transmission device a second piece of information corresponding to the first piece of information, which the power transmission device uses to determine the coupling state between the power transmission device and the power receiving device, A method characterized by having the following:

19. A program for causing a computer to perform the method described in claim 17 or 18.

Images