Wireless power reception device, wireless power supply system, and wireless power reception method

Abstract

To reliably transmit and receive data between a wireless power transmission device and a wireless power reception device when a communication failure occurs in a wireless power supply system including the wireless power transmission device and the wireless power reception device.SOLUTION: A wireless power reception device (114) of a wireless power supply system includes a power reception unit that receives power wirelessly transmitted from a wireless power transmission device, a power reception side communication unit (30) that performs wireless communication with the wireless power transmission device, and a control unit (34) that performs control to communicate with the wireless power transmission device by adjusting magnitude to second power different from first power when a communication failure occurs when communicating with the wireless power transmission device based on the first power received by the power reception unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a wireless power receiving device, a wireless power feeding system, and a wireless power receiving method. [Background technology]

[0002] Conventionally, there has been known a wireless power feeding system in which power is transmitted from a wireless power transmitting device to a wireless power receiving device in a non-contact (wireless) manner, and the power received by the wireless power receiving device is fed to a battery, etc. Also, as the wireless power feeding system, a technology is known in which data is mutually communicated between the wireless power transmitting device and the wireless power receiving device by short-range wireless communication.

[0003] For example, Patent Document 1 discloses a technology for adjusting the transmitted power based on the power transmission efficiency, which is the ratio of transmitted power to received power, and the remaining amount of stored power, in a wireless power transmission system that includes a power transmitting device having a power transmitting unit that transmits power, a power adjusting unit that adjusts the transmitted power, and a communication unit, and a power receiving device having a power receiving unit that receives power, a power detecting unit that detects the received power, a power storage unit that stores the received power, and a communication unit, in order to achieve efficient power transmission.

[0004] Furthermore, for example, Patent Document 2 discloses a wireless power transmission device including a configuration capable of supplying power wirelessly transmitted from a power transmission device to a load circuit, and the wireless power transmission device discloses a technology including a receiving resonance unit including a receiving coil and a capacitor, an impedance conversion unit that can change the impedance of the device itself as seen from the power transmission device and supply power from the receiving resonance unit to the load circuit, a detection unit that detects power information corresponding to the power supplied to the load circuit, and a control unit that determines whether to adjust at least one of the resonant frequency of the receiving resonance unit, the output frequency of the AC power supply of the power transmission device, and the resonant frequency of the transmitting resonance unit based on the magnitude relationship between first power information when the impedance of the device itself is set to a first impedance and second power information when the impedance of the device itself is set to a second impedance. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-125112 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-187958 Summary of the Invention [Problem to be solved by the invention]

[0006] In a wireless power supply system, a wireless power transmitting device and a wireless power receiving device transmit and receive data to communicate information such as the amount of power. However, if a stable supply of power is not ensured between the wireless power transmitting device and the wireless power receiving device, the two devices may not be able to accurately grasp information, resulting in communication failure. In response to this, for example, the technology disclosed in Patent Document 1, which adjusts the transmitted power, can achieve efficient power transmission, but it is difficult to deal with communication failures. Furthermore, for example, the technology disclosed in Patent Document 2, which supplies power from a power transmitting device to a load circuit, can supply power corresponding to the power supplied to the load circuit to the load circuit, but it is difficult to deal with communication failures. Therefore, there have been cases where wireless power supply systems have not adequately dealt with communication failures. For this reason, a technology for dealing with communication failures in a wireless power supply system has been desired.

[0007] The present disclosure aims to provide a wireless power receiving device, a wireless power feeding system, and a wireless power receiving method that can reliably transmit and receive data between a wireless power transmitting device and a wireless power receiving device in the event of a communication failure in a wireless power feeding system including the wireless power transmitting device and the wireless power receiving device. [Means for solving the problem]

[0008] In order to achieve the above object, the wireless power receiving device of the present disclosure includes a power receiving unit that receives power transmitted wirelessly from a wireless power transmitting device, a power receiving side communication unit that communicates wirelessly with the wireless power transmitting device, and a control unit that, when a communication failure occurs when communicating with the wireless power transmitting device based on a first power received by the power receiving unit, adjusts the magnitude of the power to a second power different from the first power and controls communication with the wireless power transmitting device.

[0009] In addition, in order to achieve the above-mentioned object, the wireless power supply system of the present disclosure is a wireless power supply system including a wireless power transmitting device and a wireless power receiving device, wherein the wireless power receiving device includes a power receiving unit that receives power transmitted wirelessly from the wireless power transmitting device, a power receiving side communication unit that communicates wirelessly with the wireless power transmitting device, and a control unit that, when a communication failure occurs when communicating with the wireless power transmitting device based on a first power received by the power receiving unit, adjusts the magnitude of the power to a second power different from the first power and controls communication with the wireless power transmitting device, and the wireless power transmitting device includes a power transmitting unit that transmits power wirelessly to the wireless power receiving device, a power transmitting side communication unit that communicates wirelessly with the wireless power receiving device, and a control unit that controls the magnitude of the power transmitted by the power transmitting unit to the wireless power receiving device based on the communication result received by the power transmitting side communication unit.

[0010] Furthermore, in order to achieve the above-mentioned object, the wireless power receiving method of the present disclosure includes processing for receiving power transmitted wirelessly from a wireless power transmitting device, communicating wirelessly with the wireless power transmitting device, and, if a communication failure occurs when communicating with the wireless power transmitting device based on a first power received by the power receiving unit, adjusting the magnitude of the second power to a second power different from the first power and controlling communication with the wireless power transmitting device. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a configuration diagram illustrating an example of a wireless power supply system according to an embodiment; [Figure 2] FIG. 1 is a conceptual diagram of communication and power supply in a wireless power supply system according to an embodiment. [Figure 3]10 is a flowchart illustrating an example of a communication control process executed by the wireless power receiving device according to the embodiment. [Figure 4] 10 is a flowchart illustrating an example of a data transmission control process executed by the wireless power transmitting device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments for realizing the technology of the present disclosure will be described in detail with reference to the drawings. In addition, components and processes that perform the same actions and functions are given the same reference numerals throughout the drawings, and duplicated explanations may be omitted as appropriate.

[0013] First, the configuration of the wireless power supply system of this embodiment will be described. FIG. 1 is a schematic diagram showing an example of a wireless power supply system 10 according to the present embodiment.

[0014] As shown in FIG. 1, a wireless power feeding system 10 of this embodiment includes a wireless power transmitting device 12 including a coil antenna 22 and a wireless power receiving device 14 including a coil antenna 32.

[0015] In the wireless power feeding system 10 of this embodiment, power is fed wirelessly and contactlessly (wirelessly) from the wireless power transmitting device 12 to the wireless power receiving device 14. In the wireless power feeding system 10 of this embodiment, a case where an electromagnetic induction method is used will be described as an example of wireless power feeding. In the wireless power feeding system 10 of this embodiment, when feeding power, the wireless power transmitting device 12 generates magnetic flux by passing an AC current through the coil antenna 22. As a result, the magnetic flux penetrating the coil antenna 32 of the wireless power receiving device 14 changes, and an AC current also flows in the coil antenna 32.

[0016] Furthermore, the wireless power feeding system 10 of this embodiment performs data communication between the wireless power transmitting device 12 and the wireless power receiving device 14 by short-range wireless communication. The short-range wireless communication performed by the wireless power feeding system 10 includes, for example, short-range wireless communication using NFC (Near Field Communication). The coil antenna 22 of the wireless power transmitting device 12 and the coil antenna 32 of the wireless power receiving device 14 have the functions of both an antenna used for wireless communication and an antenna used for wireless power feeding. The coil antenna 22 and the coil antenna 32 enable the wireless power transmitting device 12 and the wireless power receiving device 14 to switch between power feeding and information communication.

[0017] The wireless power transmitting device 12 includes a power transmitting and communication unit (hereinafter referred to as "power transmitting / communication unit") 20, a coil antenna 22, and a microcomputer (hereinafter referred to as "microcomputer") 24 equipped with a CPU.

[0018] The microcomputer 24 controls the power transmission (power supply) and communication by the power transmission / communication unit 20. The microcomputer 24 of this embodiment also controls the power supply while communicating with the wireless power receiving device 14.

[0019] A power supply voltage is input to the power transmission / communication unit 20, and power is transmitted (supplied) by passing an AC current through the coil antenna 22 in accordance with the control of the microcomputer 24. As described above, the power transmission / communication unit 20 of this embodiment performs wireless communication using the coil antenna 22 in accordance with the control of the microcomputer 24.

[0020] That is, the power transmitting / communicating unit 20 supplies power to the coil antenna 22, and the coil antenna 22 excites a nearby electromagnetic field by the power supply from the power transmitting / communicating unit 20. Furthermore, the microcomputer 24 detects a transmission signal from the wireless power receiving device 14 based on a fluctuation in the voltage level at the coil antenna 22 due to a change in the power supply state of the nearby electromagnetic field.

[0021] On the other hand, the wireless power receiving device 14 includes a power receiving / communication unit 30, a coil antenna 32, a microcomputer 34, a load modulation circuit 35, a rectifier circuit 36, a regulator 37, a switch 38, and a smoothing capacitor 44. The microcomputer 34 is driven using the power supplied from the power receiving / communication unit 30 as power supply power.

[0022] The microcomputer 34 controls the reception of power and communication by the power receiving / communication unit 30. The microcomputer 34 of this embodiment can also control communication according to data received from the wireless power transmitting device 12 and write data received from the wireless power transmitting device 12 to a memory (not shown). An example of data transmitted from the wireless power transmitting device 12 and written to a memory (not shown) is an ID (Identification) unique to the wireless power feeding system 10.

[0023] The power receiving / communicating unit 30 receives power transmitted (supplied) from the wireless power transmitting device 12 as a result of the magnetic flux density penetrating the coil antenna 32 changing due to the induced electromotive force and an alternating current flowing through the coil antenna 32. The power receiving / communicating unit 30 also performs wireless communication using the coil antenna 32 under the control of the microcomputer 34. The power receiving / communication unit 30 is an example of a power receiving unit and a power receiving-side communication unit of the present disclosure.

[0024] The power received by the power receiving / communication unit 30 is output to the battery 18 via a load modulation circuit 35, a rectifier circuit 36, a regulator 37, and a switch 38. The battery 18 in this embodiment is, for example, a secondary battery such as a lithium ion battery. The battery 18 is not particularly limited as long as it can be charged with supplied power.

[0025] The load modulation circuit 35 includes a switch (not shown) such as a transistor, and the switch (not shown) is turned on and off under the control of the microcomputer 34 to perform load modulation. The rectifier circuit 36 ​​rectifies the high-frequency signal output from the coil antenna 32. The regulator 37 converts the voltage that has passed through the rectifier circuit 36 ​​into a charging voltage appropriate for the battery 18. The regulator 37 also converts the output voltage from the battery 18 into a voltage appropriate for the microcomputer 34, etc. The smoothing capacitor 44 smoothes the voltage output from the regulator 37. The switch 38 is a load modulation communication switch connected between the regulator 37 and the smoothing capacitor 44. The microcomputer 34 obtains the input operating voltage between the rectifier circuit 36 ​​and the regulator 37, and controls the switching of the switch 38 and the switching of a switch (not shown) of the load modulation circuit 35.

[0026] As described above, the wireless power feeding system 10 operates by switching between a communication mode using load modulation and a power feeding mode in which power is transmitted. The wireless power transmitting device 12 switches its operation to the communication mode using load modulation at regular time intervals while operating in the power feeding mode, and reduces the voltage fed to the coil antenna 22 compared to that in the power feeding mode. Meanwhile, the wireless power receiving device 14 detects the input operating voltage using the microcomputer 34, determines whether the voltage is for the communication mode or the power feeding mode, and operates according to the mode.

[0027] Incidentally, in the wireless power feeding system 10, there are cases where signals transmitted and received between the wireless power transmitting device 12 and the wireless power receiving device 14 cannot be detected, resulting in communication failure. One example of a situation where the signals cannot be detected is a communication situation in an environment where a member that reflects a magnetic field, such as a metal plate, is placed near the coil antennas 22 and 32. Another example is a communication situation in an environment where the coil antennas 22 and 32 are far apart. Still another example is a communication situation in an environment where communication with a wireless device other than the wireless power feeding system 10 and communication with the wireless power feeding system 10 occur approximately simultaneously. Under such communication situations, there are cases where signals cannot be detected between the wireless power transmitting device 12 and the wireless power receiving device 14, resulting in communication failure.

[0028] Therefore, in this embodiment, a wireless power feeding system is provided that performs control to eliminate problems caused by communication failures and ensures communication between the wireless power transmitting device 12 and the wireless power receiving device 14. In addition, this embodiment has an aspect of being able to resume communication between the wireless power transmitting device 12 and the wireless power receiving device 14 that have fallen into a communication failure.

[0029] Next, the operation of the wireless power transmitting device 12 and the wireless power receiving device 14 that enable reliable data transmission and reception in the wireless power feeding system 10 of this embodiment will be described.

[0030] 2 is a conceptual diagram of communication and power supply performed between the wireless power transmitting device 12 and the wireless power receiving device 14. In the figure, an operating state 50 shows a concept of an operating state related to communication performed between the wireless power transmitting device 12 and the wireless power receiving device 14. A characteristic 52 shows a concept related to the voltage controlled by the regulator 37 of the wireless power receiving device 14. A modulation voltage characteristic 54 shows a concept related to the modulation voltage in the load modulation circuit 35 of the wireless power receiving device 14.

[0031] As shown in the operating state 50 of Fig. 2, communication and power supply are performed between the wireless power transmitting device 12 and the wireless power receiving device 14, and data is exchanged between them. Period T0 in the figure is a search period during which the wireless power transmitting device 12 searches for the wireless power receiving device 14. Period T1 is a power supply period during which the wireless power transmitting device 12 starts supplying power to the wireless power receiving device 14. Period T2 is a period during which re-communication is performed when communication failure occurs, and period T3 is a period during which communication is successful and power supply is restarted. The example in the figure shows a case where communication failure occurs in period T1, re-communication is performed in period T2, and communication is successful in period T3.

[0032] Furthermore, as shown in characteristic 52, when poor communication occurs (period T1), the voltage of the regulator 37 of the wireless power receiving device 14 is controlled (V1>V2>V3). Furthermore, as shown in modulation voltage characteristic 54, the modulation voltage in the load modulation circuit 35 fluctuates in each period. In the figure, the base power (carrier wave) due to load modulation is shown as power P0, P1, P2, and P3 corresponding to periods T0 to T3. The signal Q for communication is also shown as signals Q0, Q1, Q2, and Q3 corresponding to periods T0 to T3. The difference of signal Q from power P is also shown as difference q (q0, q1, q2, q3). The control performed by the wireless power transmitting device 12 and the wireless power receiving device 14 will be described in detail later.

[0033] 3 is a diagram showing an example of the flow of communication control processing executed by the wireless power receiving device 14, which enables resumption of communication even when communication failure occurs. The communication control processing is executed by the microcomputer 34.

[0034] In the wireless power receiving device 14, when power supply from the wireless power transmitting device 12 to the power receiving / communication unit 30 is started, the microcomputer 34 executes the communication control process shown in FIG.

[0035] In step S100, the microcomputer 34 causes the load modulation circuit 35 to perform a load modulation response (time T0 in FIG. 2). Specifically, the microcomputer 34 acquires the voltage between the rectifier circuit 36 ​​and the regulator 37 as the input operating voltage, and if the voltage level of the input operating voltage is lower than a specified value, it determines that the mode is a communication mode for communicating information, and turns off the switch 38.

[0036] Next, the microcomputer 34 performs load modulation communication by, for example, controlling the on / off of a switch (not shown) of the load modulation circuit 35 in accordance with pre-stored identification data unique to the wireless power receiving device 14, and transmits the identification data as a transmission signal to the wireless power transmitting device 12. By controlling the on / off of a switch (not shown) of the load modulation circuit 35, the impedance of the wireless power receiving device 14 as a whole changes, the power supply state from the coil antenna 32 to the coil antenna 22 changes, and the voltage level at the coil antenna 22 of the wireless power transmitting device 12 changes in accordance with the transmission signal from the wireless power receiving device 14. Therefore, the microcomputer 24 of the wireless power transmitting device 12 can detect the transmission signal from the wireless power receiving device 14. Note that the identification data used here is merely an example and is not limited to the identification data unique to the wireless power receiving device 14, and other data may be used.

[0037] 2, the magnitude (difference q0) of the transmission signal Q0 relative to the power P0, which is the base power (carrier wave) due to load modulation, becomes a magnitude that can be detected on the wireless power transmitting device 12 side. Therefore, the wireless power transmitting device 12 can confirm the identification data.

[0038] When the identification data is confirmed (e.g., authenticated) on the wireless power transmitting device 12 side, the wireless power transmitting device 12 starts operating in a power supply mode in which it transmits power, and increases the voltage supplied to the coil antenna 22. As a result, in the wireless power receiving device 14, the voltage level of the input operating voltage to the microcomputer 34 becomes higher than the specified value, and the microcomputer 34 turns on the switch 38 in step S102 to start charging the battery 18 (time period T1 in FIG. 2).

[0039] That is, the wireless power receiving device 14 switches from the communication mode to the power supply mode, and power is supplied to the battery 18 via the rectifier circuit 36, the regulator 37, and the switch 38, and the battery 18 is charged.

[0040] Next, in step S103, the microcomputer 34 determines the power receiving state of the power transmitted (supplied) from the wireless power transmitting device 12. Specifically, it determines whether the power (voltage) of the coil antenna 32 supplied from the coil antenna 22 is excessive power exceeding a predetermined threshold. If excessive power is supplied, communication is required to notify the user that the power is excessive or to request that the power be reduced. On the other hand, if the power supplied is below the threshold, communication with the wireless power transmitting device 12 is not required.

[0041] In the next step S104, the microcomputer 34 determines whether or not the determination result of step S103 indicates that communication with the wireless power transmitting device 12 is necessary. Specifically, if the determination result of step S103 indicates that there is excess power, the microcomputer 34 determines Yes in step S104 and proceeds to step S106. On the other hand, if the power supply is equal to or less than the threshold, communication with the wireless power transmitting device 12 is unnecessary, and therefore the microcomputer 34 determines No in step S104 and ends this processing routine.

[0042] In step S106, the microcomputer 34 controls the load modulation circuit 35 to perform load modulation communication so as to transmit data indicating excess power or data indicating a request to reduce power from the wireless power receiving device 14 to the wireless power transmitting device 12 (time period T1a in FIG. 2). When the data from the wireless power receiving device 14 is confirmed on the wireless power transmitting device 12 side, that is, when the communication is successful, the wireless power transmitting device 12 is controlled to reduce the power before transmitting power. Furthermore, when the communication is successful and the data is confirmed on the wireless power transmitting device 12 side, transmission information indicating that the communication is successful and the data has been confirmed is transmitted from the wireless power transmitting device 12 to the wireless power receiving device 14.

[0043] In this communication (times T1a and T1b), the magnitude of the transmission signal Q1 (difference q1) relative to the power P1 may become smaller than the magnitude detectable by the wireless power transmitting device 12 (q0>q1), as shown in the modulation voltage characteristic 54 in Fig. 2. Therefore, there is a possibility that the wireless power transmitting device 12 will not detect the data indicating excess power.

[0044] In step S108, the microcomputer 34 determines whether there has been a response from the wireless power transmitting device 12 by determining whether transmission information has been transmitted from the wireless power transmitting device 12. If there has been a response from the wireless power transmitting device 12, the microcomputer 34 makes a positive determination in step S108 and starts charging in step S118. This allows the wireless power receiving device 14 to continue charging at reduced power. On the other hand, if there is no response, the microcomputer 34 repeats a negative determination in step S110 until a predetermined time has elapsed (times T1a and T1b in FIG. 2). On the other hand, once the predetermined time has elapsed, the microcomputer 34 makes a positive determination in step S110 and proceeds to step S112.

[0045] In step S112, the microcomputer 34 adjusts power when communicating with the wireless power transmitting device 12, thereby executing the above-described communication control. Specifically, the microcomputer 34 controls the regulator 37 to adjust the voltage by a predetermined voltage (e.g., voltage drop), and controls the load modulation circuit 35 to perform load modulation communication as described above (times T2 and T3 in FIG. 2). For example, the microcomputer 34 controls the regulator 37 to drop the voltage from voltage V1 to voltage V2 and from voltage V2 to voltage V3, as shown in characteristic 52 in FIG. 2. The microcomputer 34 then repeatedly makes a negative determination in step S114 until the voltage-adjusted power reaches the specified power. Therefore, the voltage adjustment by the regulator 37 gradually drops the voltage by, for example, a predetermined voltage. This increases the likelihood of successful communication. On the other hand, if the adjusted power reaches the specified power, the microcomputer 34 makes an affirmative determination in step S114 and proceeds to step S116. In step S116, it is possible to execute a predetermined process in the wireless power receiving device 14 in response to the fact that communication is not successful within the power adjustment range up to a predetermined specified power. One example of the predetermined process is to notify the user of an abnormality by a neglect unit (not shown).

[0046] In this communication, for example, at time T2, as shown in the modulation voltage characteristic 54 in Fig. 2, the magnitude of the transmission signal Q2 is reduced relative to the power P1, but the difference q2 may be smaller than the magnitude detectable by the wireless power transmitting device 12 (q0>q2). Therefore, there is a possibility that the data indicating excess power will not be detected by the wireless power transmitting device 12. On the other hand, at time T3, the difference q3 matches or approaches the magnitude detectable by the wireless power transmitting device 12 (q0=q3), and there is a high possibility that the data indicating excess power will be detected by the wireless power transmitting device 12.

[0047] In this way, the microcomputer 34 of the wireless power receiving device 14 of this embodiment executes the above-mentioned communication control process, thereby making it possible to resume communication when a communication failure occurs (time T3 in Figure 2).

[0048] On the other hand, in the wireless power transmitting device 12 of this embodiment, the microcomputer 24 executes a data transmission control process in order to cause the wireless power receiving device 14 to execute a process for charging the battery 18.

[0049] 4 is a diagram showing an example of the flow of a data transmission control process executed by the wireless power transmitting device 12. The data transmission control process is executed by the microcomputer 24.

[0050] In step S200, the microcomputer 24 searches for the wireless power receiving device 14 by supplying power to the coil antenna 22 at a power level reduced compared to that in the power supply mode and waiting for a response (time period T0 in FIG. 2). Next, in step S202, the microcomputer 24 determines whether or not there is communication from the wireless power receiving device 14, thereby determining whether or not there is a wireless power receiving device 14. If there is communication from the wireless power receiving device 14, the microcomputer 24 determines yes in step S202 and proceeds to step S204. On the other hand, if the wireless power receiving device 14 cannot be found, for example, if there is no communication from the wireless power receiving device 14 within a predetermined time, the microcomputer 24 determines no in step S202 and ends this processing routine.

[0051] In step S202, the microcomputer 24 switches to the power supply mode, increases the reduced power, and starts power supply (time T1 in FIG. 2). Next, in step S206, the microcomputer 24 repeats a negative determination in step S206 and continues power supply until a specified time has elapsed. On the other hand, once the specified time has elapsed, the microcomputer 24 makes an affirmative determination in step S206 and proceeds to step S208. That is, the microcomputer 24 continues power supply until the specified time has elapsed.

[0052] In step S208, the microcomputer 24 communicates with the wireless power receiving device 14. Specifically, the microcomputer 24 waits for a response by a transmission signal from the wireless power receiving device 14, and then proceeds to step S210. In step S210, the microcomputer 24 determines whether there has been a response from the wireless power receiving device 14. If the response is negative, the microcomputer 24 returns to step S204 and continues power supply (times T1, T1a, T1b, and T2 in FIG. 2). On the other hand, if the result in step S210 is positive, the microcomputer 24 proceeds to step S212 (time T3 in FIG. 2). In step S212, the microcomputer 24 checks the data from the wireless power receiving device 14, processes the response content, which is the content of the data, and then ends this processing routine.

[0053] Here, if the magnitude q of the transmission signal Q relative to the power P1 from the regulator 37 becomes smaller than the magnitude detectable by the wireless power transmitting device 12, there is a high possibility that the wireless power transmitting device 12 will not detect the data indicating excess power, which may cause a communication failure. If this communication failure occurs, the data indicating excess power will not be detected, making it difficult for the wireless power transmitting device 12 to grasp the request from the wireless power receiving device 14. In contrast, in this embodiment, the wireless power receiving device 14 gradually adjusts the power P from the regulator 37, for example, by lowering the voltage, thereby helping the wireless power transmitting device 12 to detect the data. Therefore, even if a communication failure occurs in the wireless power feeding system, data can be reliably exchanged between the wireless power transmitting device and the wireless power receiving device.

[0054] In the data transmission control process executed by the wireless power transmitting device 12 of this embodiment, communication is repeatedly waited until a response is received from the wireless power receiving device 14, but if the number of times exceeds a predetermined number, this processing routine may be terminated without processing the response content.

[0055] As described above, in the wireless power feeding system 10 of this embodiment, the wireless power receiving device 14 gradually adjusts the power by the regulator 37, for example, by dropping the voltage, thereby supporting data detection by the wireless power transmitting device 12. Therefore, even if a communication failure occurs in the wireless power feeding system, data can be reliably exchanged between the wireless power transmitting device and the wireless power receiving device.

[0056] In this embodiment, the wireless power feeding system 10 is described as feeding power wirelessly by electromagnetic induction, but the method of wireless power feeding is not limited to this. For example, a magnetic resonance method, an electric field coupling method, a microwave method, etc. may be used.

[0057] Furthermore, in the wireless power supply system 10 of this embodiment, a configuration has been described in which the antenna used for wireless communication and the antenna used for wireless power supply are a common antenna (coil antenna 22 and coil antenna 32), but the present invention is not limited to this configuration, and the antenna used for wireless communication and the antenna used for wireless power supply may be provided separately.

[0058] In addition, in the wireless power feeding system 10 of the present embodiment, the wireless power receiving device 14 feeds only the power transmitted from the wireless power transmitting device 12 to the battery 18, but the present invention is not limited to this. The wireless power feeding system 10 may also be configured so that power can be fed to the battery 18 from other charging devices or the like.

[0059] In addition, in the wireless power feeding system 10 of the present embodiment, a configuration has been described in which the regulator 37 of the wireless power receiving device 14 reduces power (voltage drop) to assist the wireless power transmitting device 12 in detecting data, but the present invention is not limited to this configuration. For example, a configuration may be one in which the regulator 37 of the wireless power receiving device 14 increases power (voltage increase) to assist the wireless power transmitting device 12 in detecting data. In addition, a configuration has been described in which the regulator 37 of the wireless power receiving device 14 is applied to assist the wireless power transmitting device 12 in detecting data, but the present invention is not limited to this configuration. For example, to assist the wireless power transmitting device 12 in detecting data, the regulator 37 may be applied to another part of the wireless power receiving device 14, or an independent circuit may be added. Furthermore, in the above description, a configuration has been described in which the wireless power receiving device 14 supports data detection in the wireless power transmitting device 12, but the wireless power transmitting device 12 may be provided with the above-described function, or both the wireless power transmitting device 12 and the wireless power receiving device 14 may be provided with the above-described function.

[0060] Although the technology of the present disclosure has been described above using embodiments, the technical scope of the technology of the present disclosure is not limited to the scope described in the above embodiments. Various modifications or improvements can be made to the above embodiments without departing from the gist of the technology, and such modifications or improvements are also included in the technical scope of the disclosed technology.

[0061] Furthermore, the above-described processing may be implemented by a combination of software and hardware, or may be implemented only by hardware.

[0062] Furthermore, in order to execute the processing in the above-described embodiment using a microcomputer, a program in which the above-described processing is written in code that can be processed by a computer may be stored on a storage medium such as an optical disk and distributed.

[0063] In the above-described embodiment, a CPU can be used as a microcomputer, which is an example of a general-purpose processor. The term "processor" refers to a processor in a broad sense, and includes general-purpose processors (e.g., CPU: Central Processing Unit, etc.) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.). Furthermore, the operation of a processor may not only be performed by a single processor, but may also be performed by multiple processors working together, or may be performed by multiple processors located in physically separate locations working together.

[0064] This disclosure also includes the following:

[0065] (Appendix 1) a power receiving unit that receives power wirelessly transmitted from a wireless power transmitting device; a power receiving side communication unit that wirelessly communicates with the wireless power transmitting device; a control unit that, when a communication failure occurs when the power receiving unit communicates with the wireless power transmitting device based on a first power received by the power receiving unit, adjusts the magnitude of the power to a second power different from the first power and controls communication with the wireless power transmitting device; A wireless power receiving device comprising: (Appendix 2) the control unit determines that the communication is poor when a response corresponding to information transmitted from the wireless power transmitting device to the wireless power transmitting device is not received within a predetermined time from the wireless power transmitting device. 2. The wireless power receiving device according to claim 1. (Appendix 3) the power receiving communication unit performs communication using power that is load-modulated with a high-level side power and a low-level side power that is lower than the high-level side power, as the first power, with respect to a carrier wave power; the control unit adjusts the second power to a carrier power that is greater than or less than the carrier power of the first power received by the power receiving unit. 10. The wireless power receiving device according to claim 1 or 2. (Appendix 4) the control unit adjusts the magnitude of the second power by fine-tuning the second power so that it is larger than the first power by a predetermined power or by fine-tuning the second power so that it is smaller than the first power by a predetermined power. A wireless power receiving device according to any one of Supplementary Note 1 to Supplementary Note 3. (Appendix 5) the control unit repeatedly performs the fine adjustment using the predetermined power until a response is received from the wireless power transmitting device. 5. The wireless power receiving device according to claim 4. (Appendix 6) A wireless power supply system including a wireless power transmitting device and a wireless power receiving device, The wireless power receiving device a power receiving unit that receives power wirelessly transmitted from a wireless power transmitting device; a power receiving side communication unit that wirelessly communicates with the wireless power transmitting device; a control unit that, when a communication failure occurs when communicating with the wireless power transmitting device based on a first power received by the power receiving unit, adjusts the magnitude of the power to a second power different from the first power and controls communication with the wireless power transmitting device; Including, The wireless power transmitting device a power transmitting unit that wirelessly transmits power to the wireless power receiving device; a power transmitting side communication unit that wirelessly communicates with the wireless power receiving device; a control unit that controls the amount of power transmitted from the power transmitting unit to the wireless power receiving device based on a communication result received by the power transmitting side communication unit, Wireless power supply system. (Appendix 7) receiving power transmitted wirelessly from a wireless power transmitting device; wirelessly communicates with the wireless power transmitting device; When a communication failure occurs when communicating with the wireless power transmitting device based on the received first power, the power supply adjusts the magnitude of the power to a second power different from the first power and controls communication with the wireless power transmitting device. A wireless power receiving method including the processing.

[0066] According to the present disclosure, in a wireless power supply system including a wireless power transmitting device and a wireless power receiving device, when a communication failure occurs, it is possible to reliably exchange data between the wireless power transmitting device and the wireless power receiving device. [Explanation of symbols]

[0067] 10 Wireless power supply system 12 Wireless power transmission device 14 Wireless power receiving device 20 Power Transmission / Communication Department 24 Microcomputer 30 Power receiving / communication section 34 Microcomputer 35 Load modulation circuit 37 Regulator

Claims

1. a power receiving unit that receives power wirelessly transmitted from a wireless power transmitting device; a power receiving side communication unit that wirelessly communicates with the wireless power transmitting device; a control unit that, when a communication failure occurs when communicating with the wireless power transmitting device based on a first power received by the power receiving unit, adjusts the magnitude of the power to a second power different from the first power and controls communication with the wireless power transmitting device; A wireless power receiving device comprising:

2. the control unit determines that the communication is poor when a response corresponding to information transmitted from the wireless power transmitting device to the wireless power transmitting device is not received within a predetermined time from the wireless power transmitting device. The wireless power receiving device according to claim 1 .

3. the power receiving communication unit performs communication using power that is load-modulated with a high-level side power and a low-level side power that is lower than the high-level side power, as the first power, with respect to a carrier wave power; the control unit adjusts the second power to a carrier power that is greater than or smaller than the carrier power of the first power received by the power receiving unit. The wireless power receiving device according to claim 1 .

4. the control unit adjusts the magnitude of the second power by fine-tuning the second power so that it is larger than the first power by a predetermined power or by fine-tuning the second power so that it is smaller than the first power by a predetermined power. The wireless power receiving device according to claim 1 .

5. the control unit repeatedly performs the fine adjustment using the predetermined power until a response is received from the wireless power transmitting device. The wireless power receiving device according to claim 4 .

6. A wireless power supply system including a wireless power transmitting device and a wireless power receiving device, The wireless power receiving device a power receiving unit that receives power wirelessly transmitted from a wireless power transmitting device; a power receiving side communication unit that wirelessly communicates with the wireless power transmitting device; a control unit that, when a communication failure occurs when communicating with the wireless power transmitting device based on a first power received by the power receiving unit, adjusts the magnitude of the power to a second power different from the first power and controls communication with the wireless power transmitting device; Including, The wireless power transmitting device a power transmitting unit that wirelessly transmits power to the wireless power receiving device; a power transmitting side communication unit that wirelessly communicates with the wireless power receiving device; a control unit that controls the amount of power transmitted from the power transmitting unit to the wireless power receiving device based on a communication result received by the power transmitting side communication unit, Wireless power supply system.

7. receiving power transmitted wirelessly from a wireless power transmitting device; wirelessly communicates with the wireless power transmitting device; When a communication failure occurs when communicating with the wireless power transmitting device based on the received first power, the power is adjusted to a second power different from the first power, and control is performed to communicate with the wireless power transmitting device. A wireless power receiving method including the processing.

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