Power transmission equipment

Abstract

Highly efficient power transmission is achieved while controlling the power set in the power transmission beam so that it does not exceed the power receiving capacity of the power receiving device. [Solution] A power transmission device according to one embodiment of the present disclosure includes a control unit that controls a power transmission unit that performs wireless power transmission, and the control unit includes means for causing the power transmission unit to emit a first transmission beam set to a first power, and means for determining a second power that can be used in wireless power supply to the power receiving device by referring to feedback information regarding the reception result of the first transmission beam at the power receiving device and the power receiving capability of the power receiving device, wherein the first power is weaker than the second power.

Description

[Technical field]

[0001] The present disclosure relates to a power transmitting device, a power receiving device, a power transmission control method, a power transmission control program, a power reception control method, and a power reception control program. [Background technology]

[0002] In the field of wireless power supply, there is a demand to achieve highly efficient power transmission.

[0003] Patent document 1 describes using a backscattered signal from a mobile device to vary the phase of individual transmitting elements of an RF transmitter array in order to maximize the RF signal supplied to charge the mobile device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Application Publication No. 2019 / 0214855 Summary of the Invention [Problem to be solved by the invention]

[0005] Theoretically, it is believed that the more power transmitted to the power receiving device, the sooner the charging of the power receiving device can be completed. However, the power receiving device has a limit in its actual power receiving capacity. For example, when the power receiving device receives power that exceeds its power receiving capacity, various adverse effects such as performance degradation, deterioration, and damage may occur to the power receiving device.

[0006] An object of the present disclosure is to realize highly efficient power transmission while controlling the power set in the power transmission beam so as not to exceed the power receiving capacity of the power receiving device. [Means for solving the problem]

[0007] A power transmission device according to one embodiment of the present disclosure includes a control unit that controls a power transmission unit that performs wireless power transmission, and the control unit includes means for causing the power transmission unit to radiate a first transmission beam set to a first power, and means for determining a second power that can be used in wireless power supply to the power receiving device by referring to feedback information regarding the reception result of the first transmission beam at the power receiving device and the power receiving capability of the power receiving device, wherein the first power is weaker than the second power. Effect of the Invention

[0008] According to the present disclosure, it is possible to realize highly efficient power transmission while controlling the power set in the power transmission beam so as not to exceed the power receiving capacity of the power receiving device. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram showing a configuration of a wireless power supply system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram illustrating a configuration of a power transmitting device. [Diagram 3] 3 is a diagram illustrating a power transmission surface corresponding to the power transmission unit in FIG. 2; [Figure 4] FIG. 2 is a block diagram illustrating a configuration of a power receiving device. [Diagram 5] 5 is a diagram illustrating a power receiving surface corresponding to the power receiving unit in FIG. 4. [Figure 6] 5 is a diagram illustrating an example of a circuit configuration of a power receiving module included in the power receiving unit of FIG. 4. [Figure 7] 7 is a graph illustrating a relationship between the received power of the power receiving module of FIG. 6 and a reference voltage detected by the power receiving module. [Figure 8] FIG. 4 is a diagram showing a data structure of a power receiving class database according to the present embodiment. [Figure 9] FIG. 2 is a diagram showing an overall flow of wireless power supply processing according to the present embodiment. [Figure 10] FIG. 11 is an explanatory diagram regarding determination of power supply. [Figure 11] FIG. 11 is an explanatory diagram regarding determination of power supply. [Figure 12]FIG. 11 is an explanatory diagram regarding determination of power supply. [Figure 13] FIG. 11 is a diagram showing an overall flow of wireless power supply processing according to the first modified example. [Figure 14] FIG. 11 is a diagram showing an overall flow of wireless power supply processing in Modification 2. [Figure 15] 1 is a diagram illustrating a circuit configuration of a power receiving module that does not have a detection function. [Figure 16] 1 is a graph plotting efficiency versus input power. [Figure 17] FIG. 13 is an explanatory diagram of an overview of Modification 4. [Figure 18] 13 is a flowchart illustrating a power transmission control process according to a fourth modified example. [Figure 19] 20 is a flowchart illustrating details of step S210 in FIG. 18. [Figure 20] 10 is a diagram illustrating an example of a structure of information that a power transmitting device receives from a power receiving device. [Figure 21] 20 is a flowchart illustrating details of step S220 in FIG. 18. [Figure 22] FIG. 1 is a diagram illustrating an ideal beam shape. [Diagram 23] FIG. 1 is a diagram illustrating an ideal beam shape. [Figure 24] 13 is a flowchart illustrating a power transmission control process according to a fifth modified example. [Diagram 25] 11 is an explanatory diagram of control of a power transmission beam when the attitude of a power receiving surface changes. FIG. [Figure 26] 13 is a diagram illustrating an example of a data structure of a power receiving unit database in Modification 6. FIG. [Figure 27] FIG. 1 is an explanatory diagram of a distance measurement technique using a monocular camera. [Figure 28] FIG. 1 is an explanatory diagram of a distance measurement technique using a monocular camera. [Figure 29] 11 is an explanatory diagram of a method for determining a power ratio when a power receiving unit includes a plurality of power receiving modules. [Diagram 30] 11 is an explanatory diagram of a method for determining a power ratio when a power receiving unit includes a plurality of power receiving modules. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings for explaining the embodiment, the same components are generally designated by the same reference numerals, and the repeated description will be omitted.

[0011] (1) Wireless power transfer system configuration The configuration of the wireless power supply system will be described below. Fig. 1 is a block diagram showing the configuration of the wireless power supply system according to the present embodiment.

[0012] As shown in FIG. 1, the wireless power supply system 1 includes a power transmitting device 10 and a power receiving device 30.

[0013] The power transmitting device 10 and the power receiving device 30 are capable of wireless communication with each other. Any wireless communication method may be used, for example, Bluetooth (registered trademark), ZigBee (registered trademark), specific low-power wireless communication, or wireless LAN (Local Area Network).

[0014] In response to a power supply request from the power receiving device 30, the power transmitting device 10 wirelessly supplies power to the power receiving device 30. Specifically, the power transmitting device 10 and the power receiving device 30 operate as follows before starting to emit a power transmission beam (an example of a "second power transmission beam") with a power supply power (an example of a "second power") set (i.e., full-scale wireless power supply). The power transmitting device 10 emits a transmission beam (hereinafter referred to as a "test beam") (an example of a "first transmission beam") set to a power (an example of a "first power") weaker than the power supply power (i.e., a lower power level) toward the power receiving device 30. The power receiving device 30 transmits to the power transmitting device 10 feedback information related to the power receiving capability of the power receiving device 30 itself and the reception result of the test beam. The power transmitting device 10 refers to the feedback information to determine the power for power supply (that is, the power available for wireless power supply to the power receiving device 30).

[0015] The power receiving device 30 includes a battery (not shown). The power receiving device 30 transmits a power supply request to the power transmitting device 10, and charges the battery using the energy of the power transmission beam radiated from the power transmitting device 10. The power receiving device 30 is any electronic device that can be powered by a battery. As an example, the power receiving device 30 is a mobile computer (e.g., a smartphone, a tablet terminal, or a laptop computer), a display used for picking work in a warehouse, or a drone.

[0016] In FIG. 1, the number of the power transmitting device 10 and the power receiving device 30 is one, but the number of the power transmitting device 10 and the power receiving device 30 is not limited to one. When there are a plurality of power receiving devices 30, the power receiving device 30 may include information for identifying itself in the power supply request, thereby enabling the power transmitting device 10 to identify the power receiving device 30 (target power receiving device) that is the target of wireless power supply. When there are multiple power transmitting devices 10, multiple of them may cooperate to wirelessly feed power, or one of them may wirelessly feed power. The power transmitting device 10 that wirelessly feeds power may be specified by a target power receiving device, or may be determined by one or more power transmitting devices 10 that receive a power feed request from the target power receiving device.

[0017] (1-1) Configuration of power transmission device The configuration of the power transmitting device 10 will be described below. Fig. 2 is a block diagram illustrating the configuration of the power transmitting device. Fig. 3 is a diagram illustrating a power transmitting surface corresponding to the power transmitting unit in Fig. 2.

[0018] 2, the power transmitting device 10 includes a storage device 11, a processor 12, an input / output interface 13, a communication interface 14, and a power transmitting unit 15. The power transmitting device 10 is connectable to at least one of an input device 16 and an output device 17.

[0019] The storage device 11 is configured to store programs and data. The storage device 11 is, for example, a combination of a Read Only Memory (ROM), a Random Access Memory (RAM), and a storage (for example, a flash memory or a hard disk).

[0020] The programs include, for example, the following programs: ·OS (Operating System) programs - Application programs that perform information processing (e.g. power transmission control processing)

[0021] The data includes, for example, the following data: Databases referenced in information processing Data obtained by performing information processing (i.e., the results of performing information processing)

[0022] The processor 12 is configured to realize the functions of the power transmitting device 10 (particularly, the function of controlling the power transmitting unit 15) by starting a program stored in the storage device 11. The processor 12 is an example of a computer or a control unit.

[0023] The input / output interface 13 is configured to receive signals (e.g., user instructions, sensing data, or a combination thereof) from an input device 16 connected to the power transmission device 10, and to output signals to an output device 17 connected to the power transmission device 10.

[0024] The input device 16 is, for example, a keyboard, a pointing device, a touch screen, a sensor (eg, an optical sensor), or a combination thereof.

[0025] The optical sensor may include, for example, at least one of the following: ·camera Lidar ·ToF (Time Of Flight) camera

[0026] The output device 17 is, for example, a display, a speaker, an alarm device, or a combination thereof. When the alarm device receives an alarm output instruction from the power transmitting device 10, it outputs an alarm that can be perceived by people in the vicinity. As an example, the alarm is not limited to human vision or hearing, but stimulates touch, smell, or taste, allowing the worker to perceive at least one of the presence of the alarm itself and the content of the alarm. The alarm device includes, for example, a light source, a lamp, a display, a projector, a machine whose physical state can be electrically controlled (e.g., an electric gate for blocking people's passage), a smoke generator, a speaker, a vibration device, a mist generator, an odor generator, a taste stimulator (e.g., a mouthpiece-type device capable of supplying taste stimulator liquid to the tongue of a wearer), or a combination thereof.

[0027] The communication interface 14 is configured to control communication between the power transmitting device 10 and an external device (eg, the power receiving device 30). As an example, the communication interface 14 is a wireless communication module that supports at least one of the following standards: Bluetooth, ZigBee, specific low-power wireless communication, and wireless LAN.

[0028] The power transmission unit 15 is configured to emit the power supply electromagnetic wave as a power transmission beam (i.e., to transmit power wirelessly) in response to a control signal from the processor 12. The power supply electromagnetic wave is, for example, a microwave or a light wave (laser light or LED light). In the following description, the power supply electromagnetic wave is assumed to be a microwave.

[0029] Specifically, the power transmitting unit 15 includes a signal source, a signal processing circuit, and an antenna (an example of a "beam radiating element"). The signal source is, for example, an oscillator that generates an electromagnetic wave for power supply. The signal processing circuit performs signal processing including at least one of phase adjustment, amplitude adjustment, and filtering on the power supply electromagnetic wave generated by the signal source. The signal processing circuit may include an amplifier for amplitude adjustment (power amplification). The antenna radiates the electromagnetic waves for power supply output from the signal processing circuit into space as a power transmission beam. A lamp may be attached around the antenna as an alarm device. For example, by turning on the lamp, people in the vicinity can be made aware that wireless power transmission is in progress.

[0030] As shown in Fig. 3, the power transmitting unit 15 includes a plurality of antennas 151. The antennas 151 may be planar antennas as shown in Fig. 3, or may be linear antennas. The antennas 151 may be arranged in an array as shown in Fig. 3, or may be arranged in a different manner.

[0031] The multiple antennas 151 form a power transmission plane. The power transmission plane corresponds to a portion of the power transmission unit 15 that is responsible for emitting a power transmission beam. The power transmission plane depends on the configuration of the power transmission unit 15 (e.g., the size, shape, arrangement, and number of the antennas 151). As an example, as shown in FIG. 3, a rectangular power transmission plane TS that includes all the antennas 151 included in the power transmission unit 15 may be defined.

[0032] (1-2) Configuration of the power receiving device The configuration of the power receiving device 30 will be described. Fig. 4 is a block diagram illustrating the configuration of the power receiving device. Fig. 5 is a diagram illustrating a power receiving surface corresponding to the power receiving unit in Fig. 4. Fig. 6 is a diagram illustrating a circuit configuration of a power receiving module provided in the power receiving unit in Fig. 4. Fig. 7 is a graph illustrating the relationship between the received power of the power receiving module in Fig. 6 and the reference voltage detected by the power receiving module.

[0033] 4, the power receiving device 30 includes a storage device 31, a processor 32, an input / output interface 33, a communication interface 34, and a power receiving unit 35. The power receiving device 30 is connectable to at least one of an input device 36 and an output device 37.

[0034] The storage device 31 is configured to store programs and data, and is, for example, a combination of a ROM, a RAM, and a storage (for example, a flash memory or a hard disk).

[0035] The programs include, for example, the following programs: -OS programs Application programs that perform information processing

[0036] The data includes, for example, the following data: Databases referenced in information processing Results of information processing

[0037] The processor 32 is configured to realize the functions of the power receiving device 30 (particularly, the function of controlling the power receiving unit 35) by starting a program stored in the storage device 31. The processor 32 is an example of a computer or a control unit.

[0038] The input / output interface 33 is configured to obtain a signal (e.g., a user's instruction, sensing data, or a combination thereof) from an input device 36 connected to the power receiving device 30. In addition, the input / output interface 33 is configured to output a signal to an output device connected to the power receiving device 30.

[0039] The input device 36 is, for example, a keyboard, a pointing device, a touch screen, a sensor (eg, an orientation sensor), or a combination thereof.

[0040] The attitude sensor may include, for example, at least one of the following: Acceleration sensor Angular rate sensor Magnetic sensors

[0041] The output device 37 is, for example, a display.

[0042] The communication interface 34 is configured to control communication between the power receiving device 30 and an external device (for example, the power transmitting device 10). As an example, the communication interface 34 transmits sensing data to the external device. As an example, the communication interface 34 is a wireless communication module that supports at least one of the following standards: Bluetooth, ZigBee, specific low-power wireless communication, and wireless LAN.

[0043] The power receiving unit 35 is configured to receive the power transmission beam radiated into space by the power transmitting unit 15 and obtain power.

[0044] Specifically, the power receiving unit 35 includes an antenna and a power converter. The antenna receives electromagnetic waves for power supply (power transmission beam) propagating through space. The power converter converts the power supply electromagnetic waves received by the antenna into (DC) power. When the electromagnetic wave for power supply is a microwave, the antenna and the power converter may be a rectenna (an example of a "power receiving module"). When the electromagnetic wave for power supply is a light wave, the antenna and the power converter may be an opto-electrical converter (an example of a "power receiving module").

[0045] As shown in Fig. 5, the power receiving unit 35 includes a plurality of antennas 351. The antennas 351 may be planar antennas as shown in Fig. 5, or may be linear antennas. The antennas 351 may be arranged in an array as shown in Fig. 5, or may be arranged in a different manner.

[0046] The multiple antennas 351 form a power receiving surface (which may also be called an aperture surface). The power receiving surface corresponds to a portion of the power receiving unit 35 that is responsible for receiving the power transmission beam. The power receiving surface depends on the configuration of the power receiving unit 35 (e.g., the size, shape, arrangement, and number of the antennas 351). As an example, as shown in FIG. 5, a rectangular power receiving surface RS that includes all the antennas 351 included in the power receiving unit 35 may be defined. The power receiving surface may be an effective aperture surface based on the radio wave characteristics of the power receiving unit 35.

[0047] As shown in FIG. 6, the power receiving module included in the power receiving unit 35 includes an antenna 351, a diode D, a capacitor C, a switch SW, and a resistor R.

[0048] The anode of the diode D is grounded, and the cathode is connected to the antenna 351, the first terminal of the capacitor, and the input terminal of the switch SW. The first terminal of the capacitor C is connected to the antenna 351, the cathode of the diode D, and the input terminal of the switch SW, and the second terminal is grounded. The diode D and the capacitor C convert (i.e., rectify) the AC current output from the antenna 351 that has received the power transmission beam into a DC current.

[0049] The switch SW has one input terminal and two output terminals. The input terminal of the switch SW is connected to the antenna 351, the cathode of the diode D, and a first terminal of the capacitor C. The first output terminal of the switch SW is connected to the node N0. The second output terminal of the switch SW is connected to the node N1 and one end of the resistor R.

[0050] The switch SW shorts between the input terminal and either the first output terminal or the second output terminal in response to a control signal (not shown). Specifically, during wireless power supply (i.e., when a power transmission beam set with power supplying power is radiated), the switch SW shorts between the input terminal and the first output terminal (first switch state). As a result, a direct current obtained by the diode D and the capacitor C is guided to a battery (not shown) via the node N0. An arbitrary circuit configuration may or may not be present between the node N0 and the battery. During detection, the switch SW shorts between the input terminal and the second output terminal (second switch state), so that the DC current obtained by the diode D and the capacitor C is conducted to the resistor R.

[0051] One end of the resistor R is connected to the node N1 and the second output terminal of the switch SW, and the other end is connected to the node N2 (ground). A direct current flows through the resistor R via the switch SW when the switch SW is in the second switch state. This generates a reference voltage Vref between both ends of the resistor R (i.e., between the node N1 and the node N2). As shown in FIG. 7, the reference voltage Vref depends on the received power Prf of the power receiving module. Therefore, by identifying the received power Prf corresponding to the detected reference voltage Vref, an estimate of the received power Prf can be derived.

[0052] The power receiving device 30 includes a battery (not shown). The battery supplies power to each unit of the power receiving device 30. The battery is charged by the power obtained by the power receiving unit .

[0053] (2) Database The databases of this embodiment will be described below. The following databases are stored in at least one of the storage device 11 and the storage device 31.

[0054] (2-1) Power receiving class database The power receiving class database of this embodiment will be described. Fig. 8 is a diagram showing the data structure of the power receiving class database of this embodiment. The power receiving class database is stored in at least one of the storage device 11 and the storage device 31.

[0055] 8, the power receiving class database includes a "class" field, an "input power range" field, an "output power range" field, a "frequency" field, and an "antenna configuration" field. Each field is associated with the others. The power receiving class database stores power receiving class information (an example of "information on power receiving capability"). The power receiving class information is information on a power receiving class. The power receiving class is a concept that categorizes the power receiving capabilities that the power receiving units of various power receiving devices may have.

[0056] The power receiving capability includes, for example, at least one of the following: -Receiving surface size - Shape of the receiving surface - Power range that can be received by the power receiving unit 35 - Receivable frequencies of the power receiving unit 35 Types of polarization that can be received by the power receiving unit 35

[0057] The "class" field stores class information, which is information for identifying a class. The storage device 31 of the power receiving device 30 stores class information indicating a power receiving class to which the power receiving capability of the power receiving unit 35 included in the power receiving device 30 belongs.

[0058] The "input power range" field stores input power range information. The input power range information is information that defines the input power range (e.g., minimum and maximum values). The input power range is, for example, a recommended input power range of the power receiving module included in the power receiving unit 35. The input power range can be determined by referring to the efficiency characteristics of the power receiving module (e.g., the corresponding relationship between input power and efficiency). In this case, the input power range refers to the range of received power in which the power receiving module can operate safely and efficiently.

[0059] The "output power range" field stores output power range information. The output power range information is information that defines an output power range (e.g., minimum and maximum values). The output power range is the range of output power of the power receiving module when a received voltage within the input power range is given.

[0060] The "frequency" field stores frequency information. The frequency information is information about the frequency of the electromagnetic waves for power supply that the power receiving unit 35 can receive.

[0061] The “antenna configuration” field stores antenna configuration information. The antenna configuration information is information about the configuration of the antenna 351 provided in the power receiving unit 35.

[0062] As an example, the "antenna configuration" field includes a "spacing" field, a "number of elements" field, and a "location" field.

[0063] The “spacing” field stores antenna spacing information. The antenna spacing information is information about the spacing between adjacent antennas 351 provided in the power receiving unit 35.

[0064] The “number of elements” field stores information about the number of antenna elements. The information about the number of antenna elements is information about the number of antennas 351 included in the power receiving unit 35.

[0065] The “arrangement” field stores antenna arrangement information. The antenna arrangement information is information about the overall arrangement of the multiple antennas 351 provided in the power receiving unit .

[0066] (2-2) Received power database The received power database of this embodiment will be described. The received power database is stored in at least one of the storage device 11 and the storage device 31.

[0067] As described above, in the power receiving module included in the power receiving device 30, there is a correspondence relationship between the reference voltage Vref and the received power Prf. In order to identify the received power Prf corresponding to the reference voltage Vref, a received power database (not shown) describing such a correspondence relationship can be used. By searching the received power database using the value of the reference voltage Vref as a key, it is possible to identify the value of the corresponding received power Prf.

[0068] (3) Wireless power supply processing The wireless power supply process of this embodiment will be described. Fig. 9 is a diagram showing an overall flow of the wireless power supply process of this embodiment. Fig. 10 is an explanatory diagram regarding the determination of the power supply. Fig. 11 is an explanatory diagram regarding the determination of the power supply. Fig. 12 is an explanatory diagram regarding the determination of the power supply.

[0069] As shown in FIG. 9, the power transmitting device 10 performs radiation of a test beam (S110). Specifically, the processor 12 causes the power transmitting unit 15 to radiate a test beam toward the power receiving device 30 . As described above, the power set for the test beam is weaker than the power for power supply. This suppresses the received power of the test beam in the power receiving device 30, thereby making it possible to avoid problems caused by the received power exceeding the power receiving capability of the power receiving device 30 (for example, the maximum value of the input power range). As an example, the processor 12 may set the minimum value of a settable power range (e.g., the power when the gain of a power amplifier (not shown) is set to 0 [dB]) to the test beam. Furthermore, the processor 12 may vary the power set to the test beam depending on the power supply conditions (e.g., the position or attitude of the power receiving device 30, or the presence or absence of an obstacle).

[0070] After step S110, the power receiving device 30 detects the reference voltage (S130). Specifically, the power receiving module (FIG. 6) included in the power receiving unit 35 receives the test beam emitted in step S110. When the test beam is received, the switch SW of the power receiving module is set to the second switch state. Therefore, a reference voltage Vref is generated between the node N1 and the node N2 of the power receiving module. The processor 32 reads the value of the generated reference voltage Vref.

[0071] After step S130, the power receiving device 30 transmits feedback information (S131). Specifically, the processor 32 transmits feedback information regarding the reception result of the test beam at the power receiving unit 35 and the power receiving capability of the power receiving unit 35 to the power transmitting device 10 via the communication interface 34. As an example, the processor 32 transmits, to the power transmitting device 10, feedback information including information indicating the reference voltage Vref detected in step S130 (an example of "information related to the reception result"). When the power receiving device 30 includes a plurality of power receiving modules, the reference voltage is detected for each power receiving module. The processor 32 may transmit feedback information including information indicating all detected values ​​by the plurality of power receiving modules to the power transmitting device 10, or may transmit feedback information including information indicating some detected values ​​(for example, only the maximum value, or only the minimum value and the maximum value) to the power transmitting device 10.

[0072] In step S131, the processor 32 may further transmit, to the power transmitting device 10, feedback information including information on the power receiving capability of the power receiving device 30 (for example, class information or input power range information). The power receiving device 30 may transmit information on the power receiving capability to the power transmitting device 10 at a timing different from step S131. As an example, the power receiving device 30 may transmit information on the power receiving capability to the power transmitting device 10 before starting the wireless power supply process of Fig. 9. In this case, the information on the power receiving capability may be included in the power supply request.

[0073] After step S131, the power transmitting device 10 derives the estimated received power (S111). Specifically, the processor 12 refers to the feedback information transmitted in step S131 to identify the value of the reference voltage detected in step S130. The processor 12 refers to the received power database to identify the value of the received power corresponding to this reference voltage value. As a result, the processor 12 derives the estimated received power corresponding to the reference voltage (i.e., the estimated value of Prf). In addition, when the feedback information transmitted in step S131 includes information indicating reference voltages in multiple power receiving modules, the processor 12 may derive the estimated received power individually for all of the reference voltages, or may derive the estimated received power individually for a portion of the reference voltages (for example, only the maximum value, or only the minimum value and the maximum value).

[0074] After step S111, the power transmitting device 10 executes determination of the supply power (S112). Specifically, the processor 12 refers to the estimated received power derived in step S111 and information on the power receiving capability of the power receiving device 30 to determine the supply power.

[0075] As an example, the processor 12 refers to information related to the power receiving capability to identify a maximum value Pmax and a minimum value Pmin of the input power range of the power receiving device 30. The processor 12 calculates the power ratios (Pmax / Pest and Pmin / Pest) of the maximum value Pmax and the minimum value Pmin to the estimated received power (Pest), respectively. Processor 12 compares this power ratio range (Pmax / Pest to Pmin / Pest) with the settable gain range (Gmax to Gmin). The gain here represents the power ratio of the power supply to the power set in the test beam. In other words, if the gain of the power amplifier when radiating the test beam is 0 [dB], the gain range corresponds to the dynamic range of the power amplifier. Gmax represents the maximum gain. Gmin represents the minimum gain. In other words, if the power set in the test beam is Pt, the minimum value of the power supply is Gmin x Pt, and the maximum value of the power supply is Gmax x Pt.

[0076] As shown in FIG. 10, when there is an overlapping range (hereinafter referred to as "recommended power supply range") between the range of power ratios (Pmax / Pest to Pmin / Pest) and the gain range (Gmax to Gmin), that is, when Pmax / Pest ≧ Gmax ≧ Pmin / Pest or Pmax / Pest ≧ Gmin ≧ Pmin / Pest is satisfied, the processor 12 determines one gain (Gopt) from the recommended power supply range. As a result, the power supply is determined as Gоpt×Pt. When the power transmission unit 15 radiates a power transmission beam with the power supply set, the received power at the power receiving device 30 is expected to be within the input power range of the power receiving device 30, so that highly efficient power transmission is possible. In particular, the received power at the power receiving device 30 is expected not to exceed the maximum value of the input power range of the power receiving device 30, so that the power receiving device 30 can be safely operated. As an example, Gоpt may be set to the maximum gain within the recommended power supply range, or may be set to a gain obtained by multiplying the maximum gain by a predetermined ratio (for example, 0.9).

[0077] After step S112, the processor 12 may perform at least one of the following processes. The power receiving device 30 or the user is notified that power supply to the power receiving device 30 is possible. Waiting for a power supply start request from the power receiving device 30. A power transmission beam in which the power supply power determined in step S112 is set is radiated toward the power receiving device 30 (that is, power supply is started). The user or the power receiving device 30 is notified that the efficiency of power supply to the power receiving device 30 is high.

[0078] On the other hand, there may be a case where the recommended power supply range does not exist due to the distance between the power transmitting device 10 and the power receiving device 30 or other factors. In this case, the power transmitting device 10 may perform the error processing exemplified below.

[0079] As shown in FIG. 11, when Gmin>Pmax / Pest holds, even if the power supply power is minimized, it exceeds the maximum value Pmax of the input power range, making it difficult to transmit power to the power receiving device 30 safely and efficiently. Therefore, the processor 12 may perform at least one of the following processes. A notification is sent to the user, the power receiving device 30, or a movable mechanism of the power receiving device 30 to move the power receiving device 30 away from the power transmitting device 10. The fact that power supply to the power receiving device 30 is not possible is reported to the power receiving device 30 or a user. A notification is given to the user, the power receiving device 30, or a movable mechanism (for example, a robot arm) of the power receiving device 30 to make the power receiving surface of the power receiving device 30 not parallel to the power transmitting surface of the power transmitting device 10. -Shape the transmission beam so that it is dispersed over a wider area.

[0080] As shown in FIG. 12, when Pmin / Pest>Gmax holds, even if the power supply power is maximized, it falls below the minimum value Pmin of the input power range, making it difficult to transmit power to the power receiving device 30 with high efficiency. Therefore, the processor 12 may perform any of the following processes. A notification is sent to the user, the power receiving device 30, or a movable mechanism of the power receiving device 30 to move closer to the power transmitting device 10. Information relating to the area where power can be supplied, such as a map image, is displayed on the display of the power receiving device 30. The fact that power supply to the power receiving device 30 is not possible is reported to the power receiving device 30 or a user. A notification is sent to the user, the power receiving device 30, or the movable mechanism of the power receiving device 30 to make the power receiving surface of the power receiving device 30 parallel to the power transmitting surface of the power transmitting device 10. The user or the power receiving device 30 is notified that the efficiency of power supply to the power receiving device 30 is low.

[0081] As described above, the power transmission device according to the present embodiment emits a test beam set to a weak power compared to the power for power supply, and receives feedback information on the reception result of the test beam at the power receiving device and the power receiving capability of the power receiving device. The power transmission device then determines the power for power supply by referring to the feedback information. Therefore, according to this power transmission device, it is possible to realize highly efficient power transmission while controlling the power set in the power transmission beam after the start of wireless power supply so as not to exceed the power receiving capability of the power receiving device.

[0082] (4) Variations A modification of this embodiment will now be described.

[0083] (4-1) Variation 1 A description will be given of Modification 1. Modification 1 is an example in which the power receiving device 30 derives an estimated received power of the power receiving unit 35, and transmits feedback information including information on the estimated received power.

[0084] A description will be given of the wireless power supply processing of Modification 1. Fig. 13 is a diagram showing an overall flow of the wireless power supply processing of Modification 1.

[0085] As shown in FIG. 13, the power transmitting device 10 performs radiation of a test beam (S110) in the same manner as in FIG.

[0086] After step S110, the power receiving device 30 detects the reference voltage (S130) in the same manner as in FIG.

[0087] After step S130, the power receiving device 30 derives the estimated received power (S132). Specifically, the processor 32 refers to the received power database, and refers to the reference voltage detected in step S130, and identifies the value of the received power corresponding to the value of the reference voltage detected in step S130. In this way, the processor 32 derives the estimated received power corresponding to the reference voltage. When the power receiving device 30 includes a plurality of power receiving modules, the reference voltage is detected for each power receiving module. The processor 32 may derive the estimated received power for each of the reference voltages individually, or may derive the estimated received power for a portion of the reference voltages (for example, only the maximum value, or only the minimum value and the maximum value).

[0088] After step S132, the power receiving device 30 transmits feedback information (S131a). Specifically, the processor 32 transmits feedback information regarding the reception result of the test beam at the power receiving unit 35 and the power receiving capability of the power receiving unit 35 to the power transmitting device 10 via the communication interface 34. As an example, the processor 32 transmits to the power transmitting device 10 feedback information including information indicating the estimated received power derived in step S132 (an example of "information related to the reception result"). When the estimated received power is derived individually for multiple power receiving modules in step S132, the processor 32 may transmit feedback information to the power transmitting device 10 including information indicating the estimated received power of all of these power receiving modules, or may transmit feedback information to the power transmitting device 10 including information indicating the estimated received power of some of these power receiving modules (for example, only the maximum value, or only the minimum value and the maximum value).

[0089] In step S131a, the processor 32 may further transmit, to the power transmitting device 10, feedback information including information on the power receiving capability of the power receiving device 30 (for example, class information or input power range information). The power receiving device 30 may transmit information on the power receiving capability to the power transmitting device 10 at a timing different from that of step S131a. As an example, the power receiving device 30 may transmit information on the power receiving capability to the power transmitting device 10 before starting the wireless power supply process of Fig. 13. In this case, the information on the power receiving capability may be included in the power supply request.

[0090] After step S131a, the power transmitting device 10 executes determination of the supply power (S112a). Specifically, the processor 12 refers to the feedback information transmitted in step S131a to identify the value of the estimated received power derived in step S132. Then, the processor 12 determines the power supplying power by referring to the estimated received power and information related to the power receiving capability of the power receiving device 30. Other details related to step S112a have been described in relation to step S112 in this embodiment (see FIGS. 9 to 12).

[0091] As described above, the power transmitting device according to the first modification emits a test beam set to a weak power compared to the power for power supply, and receives feedback information on the reception result of the test beam at the power receiving device and the power receiving capability of the power receiving device. The power transmitting device then determines the power for power supply by referring to the feedback information. Therefore, according to this power transmitting device, it is possible to realize highly efficient power transmission while controlling the power set in the power transmission beam after the start of wireless power supply so as not to exceed the power receiving capability of the power receiving device.

[0092] (4-2) Variation 2 A description will now be given of Modification 2. Modification 2 is an example in which the power receiving device 30 calculates the range of the power ratio (Pmax / Pest to Pmin / Pest) described above, and transmits feedback information including information on the power ratio.

[0093] A description will be given of the wireless power supply process of Modification 2. Fig. 14 is a diagram showing an overall flow of the wireless power supply process of Modification 2.

[0094] As shown in FIG. 14, the power transmitting device 10 performs radiation of a test beam (S110) in the same manner as in FIG.

[0095] After step S110, the power receiving device 30 detects the reference voltage (S130) in the same manner as in FIG.

[0096] After step S130, the power receiving device 30 derives the estimated received power (S132) in the same manner as in FIG.

[0097] After step S132, the power receiving device 30 executes calculation of the power ratio (S133). Specifically, the processor 32 refers to information related to the power receiving capability to identify the maximum value Pmax and the minimum value Pmin of the input power range of the power receiving device 30. The processor 32 calculates the power ratios (Pmax / Pest and Pmin / Pest) of the maximum value Pmax and the minimum value Pmin to the estimated received power (Pest) derived in step S132. In step S132, when the processor 32 derives the estimated received powers individually for a plurality of power receiving modules, the processor 32 may derive the power ratios individually for all of these estimated received powers. When the estimated received power is derived individually for multiple power receiving modules in step S132, the processor 32 may calculate the power ratio for the estimated received powers of all of these power receiving modules, or may calculate the power ratio for the estimated received powers of some of these power receiving modules (e.g., only the maximum value, or only the minimum and maximum values).

[0098] After step S133, the power receiving device 30 transmits feedback information (S131b). Specifically, the processor 32 transmits feedback information regarding the reception result of the test beam at the power receiving unit 35 and the power receiving capability of the power receiving unit 35 to the power transmitting device 10 via the communication interface 34. As an example, the processor 32 transmits, to the power transmitting device 10, feedback information including information indicating the power ratio derived in step S133. When the power ratios are calculated individually for multiple power receiving modules in step S133, the processor 32 may transmit feedback information to the power transmitting device 10 including information indicating the power ratios of all of these power receiving modules, or may transmit feedback information to the power transmitting device 10 including information indicating the power ratios of some of these power receiving modules (for example, only the maximum value, or only the minimum value and the maximum value).

[0099] After step S131b, the power transmitting device 10 executes determination of the supply power (S112b). Specifically, the processor 12 refers to the feedback information transmitted in step S131b to identify the value of the power ratio derived in step S133. Then, the processor 12 refers to the power ratio to determine the power supply. Other details regarding step S112b have been described in relation to step S112 in this embodiment (see FIGS. 9 to 12).

[0100] As described above, the power transmitting device according to the second modification emits a test beam set to a weak power compared to the power for power supply, and receives feedback information on the reception result of the test beam at the power receiving device and the power receiving capability of the power receiving device. The power transmitting device then determines the power for power supply by referring to the feedback information. Therefore, according to this power transmitting device, it is possible to realize highly efficient power transmission while controlling the power set in the power transmission beam after the start of wireless power supply so as not to exceed the power receiving capability of the power receiving device.

[0101] (4-3) Variation 3 Modification 3 is an example in which, when the power receiving unit 35 includes a plurality of power receiving modules, some of the power receiving modules do not have a circuit configuration for implementing a detection function (i.e., a circuit configuration for detecting a reference voltage). Fig. 15 is a diagram illustrating a circuit configuration of a power receiving module that does not have a detection function.

[0102] As shown in FIG. 15, the power receiving module included in the power receiving unit 35 includes an antenna 351, a diode D, and a capacitor C.

[0103] The anode of the diode D is grounded, and the cathode is connected to the antenna 351, the first terminal of the capacitor, and the node N0. The first terminal of the capacitor C is connected to the antenna 351, the cathode of the diode D, and the node N0, and the second terminal is grounded. The diode D and the capacitor C convert (i.e., rectify) the AC current output from the antenna 351 that receives the power transmission beam into a DC current. The DC current obtained by the diode D and the capacitor C is conducted to a battery (not shown) via the node N0. An arbitrary circuit configuration may or may not be present between the node N0 and the battery.

[0104] Any part of the multiple power receiving modules included in the power receiving unit 35 may be replaced with a power receiving module as shown in Fig. 15. However, as described below, in order to monitor the received power at a specific position, it is preferable that the power receiving module arranged near the specific position has a circuit configuration for realizing a detection function.

[0105] For example, the power transmission beam may be shaped so that the power level is highest near the center of the receiving surface. In this case, the power receiving module including the antenna 351 arranged near the center of the receiving surface is more likely to receive power that exceeds the power receiving capacity than other power receiving modules. Therefore, it is preferable that such a power receiving module has a circuit configuration for realizing a detection function.

[0106] The power transmission beam may also be shaped to fit the edge (i.e., side or vertex) of the power receiving surface at the position of the power receiving device 30. In this case, the received power at the power receiving module including the antenna 351 arranged near the edge of the power receiving surface can be used to detect that the power transmission beam is not shaped in an ideal shape (e.g., rotational deviation or undersize). Therefore, it is preferable that such a power receiving module has a circuit configuration for realizing a detection function.

[0107] As described above, the power receiving device of variant 3 can achieve the same effects as the power receiving devices of this embodiment or variants 1 and 2 while simplifying the configuration of some of the power receiving modules compared to these power receiving devices.

[0108] (4-4) Variation 4 The fourth modification is an example in which the power transmitting device 10 shapes the transmission beam by referring to static information and dynamic information of the power receiving unit before emitting the test beam (S110). That is, according to the fourth modification, the power transmitting device 10 emits a shaped test beam.

[0109] (4-4-1) Overview of the embodiment An overview of Modification 4 will be described below. Fig. 17 is an explanatory diagram of an overview of Modification 4.

[0110] The power transmitting device 10 of the fourth modification specifies the size and shape of a power receiving surface corresponding to the power receiving unit 35 of the power receiving device 30, in addition to the position and attitude of the power receiving surface. Then, the power transmitting device 10 shapes and radiates the power transmitting beam so that the power transmitting beam is focused on a spot that matches the attitude, size, and shape of the power receiving surface at the position of the power receiving surface. As an example, the power transmitting device 10 causes the multiple antennas 151 to radiate RF beams with different phases and different amplitudes.

[0111] In short, as shown in Fig. 17, the power transmitting device 10 prevents leakage of electromagnetic waves outside the power receiving surface RS by concentrating the power transmitting beam PTB on the power receiving surface RS. Therefore, it is possible to suppress adverse effects on living organisms and devices caused by electromagnetic waves leaking around the power receiving device 30. In addition, since the power transmitting beam PTB reaches, for example, the entire area of ​​the power receiving surface RS, it is possible to bring out the overall power receiving performance of the multiple antennas 351 provided in the power receiving unit 35. In other words, it is possible to increase the amount of power that can be received per unit time and realize highly efficient power transmission.

[0112] (4-4-2) Power transmission control processing The power transmission control process of the modified example 4 will be described. FIG. 18 is a flowchart illustrating the power transmission control process of the modified example 4. FIG. 19 is a flowchart illustrating the details of step S210 in FIG. 18. FIG. 20 is a diagram illustrating the structure of information received by the power transmitting device from the power receiving device. FIG. 21 is a flowchart illustrating the details of step S220 in FIG. 18. FIG. 22 is a diagram illustrating an ideal beam shape. FIG. 23 is a diagram illustrating an ideal beam shape.

[0113] The power transmission control process in FIG. 18 starts, for example, in response to the processor 12 acquiring a power supply request received from the power receiving device 30 via the communication interface 14.

[0114] As shown in FIG. 18, the power transmitting device 10 executes identification of static information related to the power receiving surface (S210). Specifically, the processor 12 identifies static information regarding the power receiving surface.

[0115] The static information regarding the power receiving surface is information regarding the attributes or state of the power receiving surface that is assumed not to change between the start and end of wireless power supply. As an example, the static information is the size and shape of the power receiving surface.

[0116] The size of the receiving surface represents the actual size of the receiving surface. For example, the size of the receiving surface may include at least one of the following: The length of part or all of the contour line that defines the receiving surface (for example, the length of the sides of the receiving surface or the total length of the receiving surface) The length between two points on the contour that defines the receiving surface (for example, the length of the diagonal of the receiving surface, the radius of the receiving surface, the length of the major axis of the receiving surface, or the length of the minor axis of the receiving surface) - Area enclosed by the contour line that defines the receiving surface

[0117] The shape of the power receiving surface represents the geometric shape of the power receiving surface. The shape of the power receiving surface may be, for example, a combination of any curved lines (e.g., a circle or an ellipse), a combination of any straight lines (e.g., a polygon), or a combination of any curved lines and straight lines (e.g., a sector).

[0118] As an example, the static information regarding the power receiving surface is specified (S210) according to FIG.

[0119] As shown in FIG. 19, the power transmitting device 10 executes size specification (S211). Specifically, the processor 12 refers to the information received from the power receiving device 30 to identify the size of the power receiving surface.

[0120] As an example, the communication interface 14 of the power transmission device 10 receives information having the structure shown in Fig. 20 from the power receiving device 30. A part or all of this information may be included in a power supply request transmitted from the power receiving device 30 to the power transmission device 10, for example. As shown in FIG. 20, the information received from the power receiving device 30 may include size information, shape information, and attitude information in addition to the power receiving unit ID. The power receiving unit ID is information for identifying the power receiving unit 35 included in the power receiving device 30 that is the transmission source. The power receiving unit ID is stored in the storage device 31 of the power receiving device 30, for example. The size information is information about the size of the power receiving surface corresponding to the power receiving unit 35 identified by the power receiving unit ID. The size information is stored in the storage device 31 of the power receiving device 30, for example. The shape information is information about the shape of a power receiving surface corresponding to the power receiving unit 35 identified by the power receiving unit ID. The shape information is stored in the storage device 31 of the power receiving device 30, for example. The attitude information is information about the attitude of the power receiving surface corresponding to the power receiving unit 35 identified by the power receiving unit ID. As one example, the attitude information is generated by the processor 32 of the power receiving device 30 according to the sensing result of the attitude sensor (one example of the input device 36). As another example, the attitude information can also be generated by using a reception phase difference between the power receiving antenna elements for the incoming signal.

[0121] The processor 12 extracts information about the size of the power receiving surface from the information received from the power receiving device 30. The processor 12 identifies the size of the power receiving surface by referring to the extracted information.

[0122] As shown in FIG. 19, the power transmitting device 10 executes the shape specification (S212). Specifically, the processor 12 refers to the information received from the power receiving device 30 to identify the shape of the power receiving surface. As an example, the processor 12 extracts information about the shape of the power receiving surface from the information (FIG. 20) received from the power receiving device 30. The processor 12 identifies the shape of the power receiving surface by referring to the extracted information. Step S212 may be executed after step S211 as in FIG. 19, or may be executed before step S211 or simultaneously with step S211.

[0123] As shown in FIG. 18, the power transmitting device 10 executes identification of dynamic information related to the power receiving surface (S220). Specifically, the processor 12 determines dynamic information regarding the power receiving surface. Step S220 may be performed after step S210 as in FIG. 19, or may be performed before step S210 or simultaneously with step S210.

[0124] The dynamic information on the power receiving surface is information that is assumed to be likely to change among the attributes or states of the power receiving surface between the start and end of wireless power supply. As an example, the dynamic information is the position of the power receiving surface and the attitude of the power receiving surface. If the power receiving device 30 moves or rotates between the start and end of wireless power supply, at least one of the position of the power receiving surface and the attitude of the power receiving surface changes.

[0125] The position of the power receiving surface represents a relative position of the power receiving surface with respect to the power transmitting surface. For example, the position of the power receiving surface may include at least one of the following: The coordinates of one or more reference points (e.g., vertices) on the contour that defines the power receiving surface The coordinates of one or more reference points (e.g., the center point and / or the center of gravity) within the power receiving surface

[0126] The attitude of the power receiving surface represents the relative orientation of the power receiving surface with respect to a reference plane (e.g., a horizontal plane or a power transmitting plane). As an example, the attitude of the power receiving surface is the inclination of the power receiving surface with respect to the reference plane (e.g., at least one of the roll angle, pitch angle, and yaw angle of the power receiving surface).

[0127] As an example, the dynamic information regarding the power receiving surface is identified (S220) according to FIG.

[0128] As shown in FIG. 21, the power transmitting device 10 executes the location specification (S221). Specifically, the processor 12 identifies the position of the power receiving surface. The position of the power receiving surface can be identified by various techniques. The processor 12 preferably identifies the position of the power receiving surface without wirelessly transmitting power. This eliminates the need to emit a power transmission beam to identify the position of the power receiving surface, and therefore does not adversely affect surrounding living organisms or devices when identifying the position of the power receiving surface. In the fourth modification, the processor 12 identifies the position of the power receiving surface by referring to the sensing result of an optical sensor (an example of an input device 16).

[0129] As an example, the processor 12 refers to an image of the power receiving device 30 captured by a camera and measures the distance from the camera to the target part. The processor 12 can then identify the position of the power receiving surface based on the measured distance and known parameters (e.g., the positional relationship between the camera and the power transmitting surface, the camera's shooting conditions (e.g., the angle of view and the angle), and the positional relationship between the target part and the power receiving surface (e.g., the center point of the power receiving surface)). The processor 12 may also identify the position of the power receiving surface by referring to the measurement results of a distance measurement sensor (e.g., an ultrasonic sensor, Lidar, etc.).

[0130] The target portion is a feature that is observable from the outside of the power receiving device 30. The target portion may include, for example, at least one of the following: A portion of the power receiving device 30 or a cover covering the power receiving device 30 to which a mark (for example, at least one of a two-dimensional barcode, a specific unevenness, a specific pattern, a specific color, and a specific shape) is given. At least one vertex, corner, edge, or entirety of the antenna 351 - Vertices, corners, edges, or the entirety of the power receiving unit 35

[0131] As shown in FIG. 21, the power transmitting device 10 executes a step of identifying the posture (S222). Specifically, the processor 12 refers to the information received from the power receiving device 30 to identify the orientation of the power receiving surface. As an example, the processor 12 extracts information regarding the orientation of the power receiving surface from the information (FIG. 20) received from the power receiving device 30. The processor 12 identifies the orientation of the power receiving surface by referring to the extracted information. Step S222 may be executed after step S221 as in FIG. 21, or may be executed before step S221 or simultaneously with step S221.

[0132] After steps S210 and S220, the power transmitting device 10 generates control parameters (S230). Specifically, the processor 12 generates control parameters (for example, beam excitation conditions) related to beam formation by referring to the static information of the power receiving surface identified in step S210 and the dynamic information of the power receiving surface identified in step S220. As an example, the processor 12 generates control parameters so that the transmission beam emitted from the power transmitting unit 15 is focused into a spot at the position of the power receiving surface that matches the size, shape, and attitude of the power receiving surface. As a result, the transmission beam is concentrated over almost the entire area of ​​the receiving surface, making it possible to bring out the majority of the receiving performance of the antenna 351 provided in the receiving unit 35 (i.e., to realize highly efficient wireless power transmission), while at the same time suppressing leakage of electromagnetic waves to the surroundings of the receiving unit 35.

[0133] The control parameters in the first example are determined so that the intensity of the power transmission beam is half the maximum value (i.e., half value) at least on a part of the edge (i.e., side or vertex) of the power receiving surface as shown in Fig. 22. This makes it possible to efficiently transmit power while suppressing the variation in the received power between the antennas 351.

[0134] The control parameters in the second example are determined so that the intensity of the power transmission beam becomes null (i.e., zero value) on at least a part of the edge of the power receiving surface as shown in Fig. 23. This can further increase the efficiency of power transmission.

[0135] After step S230, the power transmitting device 10 performs wireless power transmission (S240). Specifically, the processor 12 causes the power transmitter 15 to emit a power transmission beam in accordance with the control parameters generated in step S230. In step S240, the power transmitting device 10 and the power receiving device 30 perform the wireless power supply process of FIG. 9, FIG. 13, or FIG.

[0136] After step S240, the power transmitting device 10 executes a power transmission end determination (S250). Specifically, the processor 12 determines whether or not the power transmission has ended. For example, the processor 12 may determine that the power transmission has ended when at least one of the following conditions is satisfied. The capacity of the battery of the power receiving device 30 reaches a threshold value (e.g., fully charged) (for example, by referring to information received from the power receiving device 30). The power receiving device 30 cannot be detected (for example, the wireless connection with the power receiving device 30 is disconnected). A power transmission end request is received from the power receiving device 30. Vibration of the power receiving device 30 is detected (the power receiving device 30 can transmit a vibration detection signal when vibration of the power receiving device 30 is detected by a vibration sensor provided in the power receiving device 30). A human presence sensor connected to the power transmission device 10 detects a person. A power transmission end signal is received (for example, from a remote controller not shown). A certain amount of time has passed since the start of wireless power transmission.

[0137] If it is determined in step S250 that the power transmission has ended, the power transmitting device 10 ends the power transmission control process.

[0138] When it is determined in step S250 that the power transmission has not ended, the power transmitting device 10 performs wireless power transmission (S240) and power transmission end determination (S250) again.

[0139] As described above, the power transmitting device of the fourth modification specifies the size and shape of the power receiving surface in addition to the position and attitude of the power receiving surface corresponding to the power receiving unit of the power receiving device. Then, the power transmitting device shapes and radiates the power transmitting beam so that the power transmitting beam is focused on a spot that matches the attitude, size, and shape of the power receiving surface at the position of the power receiving surface. In this way, the power transmitting device focuses the power transmitting beam on the power receiving surface and prevents the electromagnetic waves from leaking outside the power receiving surface. Therefore, it is possible to suppress adverse effects on living organisms and devices caused by the electromagnetic waves leaking around the power receiving device. In addition, since the power transmitting beam reaches, for example, the entire area of ​​the power receiving surface, it is possible to bring out the overall power receiving performance of the multiple antennas provided in the power receiving unit. In other words, it is possible to increase the amount of power that can be received per unit time and realize highly efficient power transmission.

[0140] (4-5-1) Variation 5 A description will now be given of Modification 5. Modification 5 is an example of Modification 4 in which the control parameters are updated in response to a change in dynamic information related to the power receiving surface.

[0141] The following describes the power transmission control process of Modification 5. Fig. 24 is a flowchart illustrating the power transmission control process of Modification 5. Fig. 25 is an explanatory diagram of the control of the power transmission beam when the attitude of the power receiving surface changes.

[0142] As shown in FIG. 24, similar to FIG. 18, the power transmission device 10 performs identification of static information regarding the power receiving surface (S210), identification of dynamic information regarding the power receiving surface (S220), generation of control parameters (S230), wireless power transmission (S240), and power transmission end determination (S250).

[0143] If it is determined in step S250 that the power transmission has ended, the power transmitting device 10 ends the power transmission control process, similarly to FIG.

[0144] If it is determined in step S250 that power transmission has not ended, the power transmission device 10 again performs the steps of identifying dynamic information regarding the power receiving surface (S220), generating control parameters (S230), wireless power transmission (S240), and determining whether power transmission has ended (S250), unlike in FIG. 18. This makes it possible to update the control parameters in response to changes in dynamic information about the power receiving surface. For example, when the attitude of the power receiving surface changes due to rotation, the change in the attitude of the power receiving surface can be tracked by changing the rotation angle of the power transmission beam PTB, as shown in Fig. 25.

[0145] As described above, according to the power transmitting device of the fifth modification, even if at least one of the position and the attitude of the power receiving surface changes, the power transmitting beam can be adaptively shaped. In other words, it is possible to realize highly efficient wireless power transmission while suppressing leakage of electromagnetic waves in a robust manner against the movement (translation or rotation) of the power receiving device.

[0146] (4-2) Variation 6 A description will be given of Modification 6. Modification 6 is an example in which static information related to the power receiving surface in Modification 4 or Modification 5 is stored in advance in the storage device 11 of the power transmitting device .

[0147] In the sixth modification, the processor 12, in step S210 of FIG. 18 or FIG. 24, identifies static information related to the power receiving surface by referring to the power receiving unit database stored in the storage device 11.

[0148] 26 is a diagram illustrating an example of a data structure of the power receiving unit database in Modification 6. The power receiving unit database is stored in the storage device 11.

[0149] 26, the power receiving unit database includes a "power receiving unit ID" field, a "shape" field, and a "size" field. Each field is associated with the other fields. In the power receiving unit database, static information regarding the power receiving surface corresponding to each power receiving unit 35 is registered.

[0150] The "power receiving unit ID" field stores the power receiving unit ID described above.

[0151] The "shape" field stores the above-mentioned shape information.

[0152] The "size" field stores the size information described above.

[0153] For example, when the power transmission device 10 wirelessly transmits power to the power receiving unit 35 for the first time, or when the power receiving unit 35 is registered in the power transmission device 10 as one of the power supply targets, the processor 12 may refer to the information received from the power receiving device 30 and register static information regarding the power receiving surface corresponding to the power receiving unit 35 in the power receiving unit database, or a human may manually register the static information regarding the power receiving surface corresponding to the power receiving unit 35 in the power receiving unit database.

[0154] At least one of the shape information and the size information may be associated with model information instead of the power receiving unit ID. The model information is information about the model of at least one of the power receiving device 30 and the power receiving unit 35.

[0155] As described above, according to the power transmitting device of the sixth modification, static information on the power receiving surface is stored in advance in the storage device 11 of the power transmitting device 10. Therefore, it is possible to identify the static information on the power receiving surface and shape the power transmission beam without receiving the static information on the power receiving surface from the power receiving device 30 every time wireless power transmission is performed. In other words, even in a situation where it is difficult or impossible to receive information from the power receiving device 30, it is possible to realize highly efficient wireless power transmission while suppressing leakage of electromagnetic waves.

[0156] (5) Other modifications The storage device 11 may be connected to the power transmitting device 10 via a network NW. The storage device 31 may be connected to the power receiving device 30 via the network NW.

[0157] In the embodiment, an example in which the power receiving device transmits a power supply request to the power transmitting device has been described. However, the wireless transmission device may wirelessly supply power to any of the power receiving devices without receiving a power supply request. As an example, the wireless transmission device may wirelessly supply power according to a predetermined schedule, or may collect battery capacity information from the power receiving device to determine whether or not wireless power supply is required.

[0158] In the embodiment, the power receiving class information is used as the information on the power receiving capability. However, the information on the power receiving capability can be arbitrarily determined. As an example, the information on the power receiving capability may be information on the efficiency with respect to the input power of the power receiving unit 35. FIG. 16 is a graph plotting the efficiency with respect to the input power. For example, with respect to the efficiency, the minimum value of the input power range in which the drop from the maximum value is within a predetermined value or a predetermined ratio may be determined as Pmin, and the maximum value may be determined as Pmax.

[0159] In the embodiment, an example has been shown in which the power ratios (Pmax / Pest and Pmin / Pest) of the maximum value Pmax and the minimum value Pmin to the estimated received power (Pest) are calculated. However, when the power receiving unit 35 includes a plurality of power receiving modules, the power density varies among the power receiving modules. Therefore, as shown in FIG. 29, the processor 12 may calculate a ratio (Pmax / Pest1) of the maximum value Pmax to the first estimated received power (Pest1) and a ratio (Pmin / Pest2) of the minimum value Pmin to the second estimated received power (Pest1). The first estimated received power is the maximum value of the estimated received power across multiple power receiving modules. The second estimated received power is the minimum value of the estimated received power across multiple power receiving modules. In FIG. 29, the ratio (Pmax / Pest1) represents the upper limit of the power ratio at which all modules can be operated safely, and the ratio (Pmin / Pest2) represents the lower limit of the power ratio at which all modules can be operated efficiently. However, as shown in FIG. 30, when Pmax / Pest1>Pmin / Pest2 is not satisfied, the processor 12 may change the second estimated received power to a larger value. Specifically, the processor 12 sets the minimum value among the estimated received powers of a plurality of power receiving modules that can satisfy Pmax / Pest1>Pmin / Pest2 as Pest2. In the example of FIG. 30, the received power Pe1 of the module 1 is the minimum, but if the module 1 is to be operated efficiently, the module 2 cannot be operated safely. Therefore, the estimated received power Pe1 of the module 1 is excluded from the candidates for the second estimated received power. Then, the processor 12 selects the estimated received power Pe3 of the module 3, which has the minimum estimated received power among the remaining modules, as the second estimated received power. In this case, Pmax / Pest1>Pmin / Pest2 is satisfied. 30, the ratio (Pmax / Pest1) represents the upper limit of the power ratio at which all modules can be operated safely, and the ratio (Pmin / Pest2) represents the lower limit of the power ratio at which modules 2 and 3 can be operated efficiently. In this way, even if Pmax / Pest1>Pmin / Pest2 does not hold, by changing the second estimated received power, it is possible to find a power range at which more modules can be operated efficiently while ensuring the safe operation of all modules.

[0160] The power receiving device 30 may detect whether an output voltage is generated in each of the multiple power receiving modules included in the power receiving unit 35 when receiving a test beam or a power transmitting beam with a power supply set. Furthermore, when the power receiving device 30 detects a module that is not generating an output voltage, the power receiving device 30 may stop power transmission by transmitting a power transmission end request or the like. In addition, the power receiving device 30 may notify the user of the stop of power transmission before or after stopping the power transmission. This can prevent malfunctions caused by a beam being irradiated to the power receiving device 30 in which some of the power receiving modules are broken.

[0161] In the embodiment, when there is an overlapping range (hereinafter referred to as a "recommended power supply range") between the power ratio range (Pmax / Pest to Pmin / Pest) and the gain range (Gmax to Gmin), the processor 12 determines one gain (Gopt) from the recommended power supply range. However, the processor 12 does not need to consider the power ratio Pmin / Pest. Specifically, when Pmax / Pest≧Gmax≧Gmin holds, the processor 12 determines one gain (Gopt) from the gain range (Gmax to Gmin). Also, when Gmax≧Pmax / Pest≧Gmin holds, the processor 12 determines one gain (Gopt) from the gain range (Pmax / Pest to Gmin). When the power transmission unit 15 emits a transmission beam with such power supply set, the received power at the power receiving device 30 is not expected to exceed the maximum value of the input power range of the power receiving device 30, so the power receiving device 30 can be operated safely.

[0162] In the embodiment, an example in which the power transmitting device includes one power transmitting unit has been described. However, the power transmitting device may include multiple power transmitting units that can be individually controlled. Furthermore, the power transmitting unit and other components (e.g., a control unit) in the power transmitting device may be configured as separate devices that can communicate with each other. In other words, the power transmitting device does not need to include a power transmitting unit. In this case, the power transmitting unit may be incorporated into a device that includes a communication interface for receiving control parameters from the power transmitting device and a processor (e.g., a microcomputer) for driving the power transmitting unit according to the control parameters from the power transmitting device. Similarly, the power receiving unit and other components (for example, a control unit) in the power receiving device may be configured as separate devices capable of communicating with each other. In other words, the power receiving device does not need to include a power receiving unit.

[0163] In the embodiment, an antenna is given as an example of a beam emitting element. However, when a light wave is used as the electromagnetic wave for power supply, the beam emitting element may be a light emitting element such as a laser element or an LED chip.

[0164] In the embodiment, an example has been shown in which the power receiving device 30 transmits information (e.g., class information or input power range information) related to the power receiving capability of the power receiving device 30 to the power transmitting device 10. However, the power transmitting device 10 may also identify information related to the power receiving capability of the power receiving device 30 without the power receiving device 30 transmitting information related to the power receiving capability. For example, the processor 12 may read a code (e.g., a two-dimensional barcode) attached to the power receiving device 30 or a cover that covers the power receiving device 30, and thereby read the information related to the power receiving capability stored in the code.

[0165] Regarding the fourth to sixth modifications, the static information of the power receiving surface (eg, at least one of the size and the shape) can be determined by a technique different from the technique described above. For example, the processor 12 may read a code (e.g., a two-dimensional barcode) attached to the power receiving device 30 or a cover covering the power receiving device 30, and read information about the size of the power receiving surface stored in the code.

[0166] In the fourth to sixth modified examples, an example has been shown in which an image of the power receiving device 30 captured by a camera is referred to and the distance from the camera to a target part is measured. The camera may be a stereo camera or a monocular camera. By using a monocular camera, the power transmitting device 10 can be realized at a smaller size and lower cost than when a stereo camera is used. An example of a technique for measuring the distance from the monocular camera to a target part by referring to an image of the power receiving device 30 captured by the monocular camera will be described below. The monocular camera captures an image of a subject including a target part OP, as shown in FIG. 27. The processor 12 extracts an area corresponding to the target part OP by performing image processing on the image captured by the monocular camera, as shown in FIG. 28. The processor 12 counts the number of pixels in the area corresponding to the target part OP. Here, the number of pixels in the area corresponding to the target part OP depends on the distance from the monocular camera to the target part OP. If the number of pixels when the distance=L is S1 and the number of pixels when the distance=X is S2, then X=L×√(S1 / S2) holds. By determining the reference distance L and the reference number of pixels S1 as constants in advance, the processor 12 can derive X as a function of S2. As an example, when L=100[cm] and S1=600×400[pixels], and S2=300×200[pixels] is counted, X=200[cm] from the above formula. The reference distance L and the reference pixel number S1 may be included in the static information of the power receiving surface. In other words, the reference distance L and the reference pixel number S1 may be identified by reading information stored in a code (e.g., a two-dimensional barcode) attached to the power receiving device 30 or a cover that covers the power receiving device 30, or the power receiving device 30 may transmit such information to the power transmitting device 10.

[0167] The location of the power receiving surface can also be determined by techniques other than those described above. As a first example, the power receiving device 30 may specify the position of the power transmitting surface relative to the power receiving surface by, for example, referring to the sensing result of an optical sensor (an example of the input device 36) and transmit information on the specified position to the power transmitting device 10. The power transmitting device 10 can specify the relative position of the power receiving surface with respect to the power transmitting surface by converting the position specified by the power receiving device 30 so that the position of the power transmitting surface becomes the origin. As a second example, the power receiving device 30 may be fixed by a support that is installed so that the relative position of the power receiving surface with respect to the power transmitting surface is a predetermined value. This allows the processor 12 to specify the position of the power receiving surface as the predetermined value without measuring the relative position of the power receiving surface with respect to the power transmitting surface. The predetermined value may be stored in the storage device 11 before the start of wireless power supply. As a third example, the power transmitting device 10 measures the absolute coordinates (e.g., latitude, longitude, and altitude) of the power transmitting surface, for example, by using a Global Positioning System (GPS). Similarly, the power receiving device 30 measures the absolute coordinates of the power receiving surface, for example, by using a GPS, and transmits information on the measured absolute coordinates to the power transmitting device 10. The power transmitting device 10 can identify the relative position of the power receiving surface with respect to the power transmitting surface by subtracting the absolute coordinates of the power transmitting surface from the absolute coordinates of the power receiving surface.

[0168] The orientation of the power receiving surface can also be determined by techniques other than those described above. Specifically, the processor 12 may identify the orientation of the power receiving surface by referring to the sensing result of the optical sensor. As an example, the processor 12 may identify the orientation of the power receiving surface by performing image processing (e.g., extraction of vertices of the power receiving surface and matching between the extracted vertices and the shape of the power receiving surface) on the image of the power receiving device 30 captured by the camera. As a second example, the power receiving device 30 may be fixed by a support that is installed so that the orientation of the power receiving surface relative to the power transmitting surface is a predetermined value. This allows the processor 12 to specify the orientation of the power receiving surface as the predetermined value without measuring the orientation of the power receiving surface relative to the power transmitting surface. The predetermined value may be stored in the storage device 11 before the start of wireless power supply.

[0169] In the fourth to sixth modified examples, the control parameters are generated by referring to the position, size, shape, and orientation of the power receiving surface. However, the control parameters may be generated without referring to at least one of the shape and the orientation. As a first example, the processor 12 may generate control parameters such that the power transmission beam emitted from the power transmitting unit 15 is focused into a spot at the position of the power receiving surface that matches the size of the power receiving surface. As a second example, the processor 12 may generate the control parameters so that the transmission beam emitted from the power transmitting unit 15 is focused into a spot at the position of the power receiving surface that matches the size and shape of the power receiving surface. As a third example, the processor 12 may generate the control parameters so that the power transmission beam emitted from the power transmission unit 15 is focused at the position of the power receiving surface into a spot that matches the size and attitude of the power receiving surface.

[0170] In the fourth to sixth modified examples, the power transmission end determination (S250) is performed after step S240. However, step S250 may be performed at other timings. For example, the processor 12 may immediately perform step S250 and determine that power transmission has ended when a predetermined interrupt event occurs. The interrupt event may include at least one of the following, for example. The battery capacity of the power receiving device 30 reaches a threshold value. - The power receiving device 30 cannot be detected. A power transmission end request is received from the power receiving device 30. Vibration of the power receiving device 30 is detected (the power receiving device 30 can transmit a vibration detection signal when vibration of the power receiving device 30 is detected by a vibration sensor provided in the power receiving device 30). A human presence sensor connected to the power transmission device 10 detects a person. - Power transmission end signal received A certain amount of time has passed since the start of wireless power transmission.

[0171] Although the embodiment of the present invention has been described in detail above, the scope of the present invention is not limited to the above embodiment. Furthermore, the above embodiment can be improved or modified in various ways without departing from the spirit of the present invention. Furthermore, the above embodiment and the modified examples can be combined.

[0172] (6) Additional Notes The matters described in the embodiment and the modified examples are supplemented below.

[0173] (Appendix 1) The power supply device includes a control unit (12) that controls a power transmission unit (15) that performs wireless power transmission. The control unit A means (S110) for causing a power transmitting unit to radiate a first power transmission beam having a first power set thereto; A means (S112) for determining a second power available for wireless power feeding to the power receiving device by referring to feedback information relating to a reception result of the first power transmission beam in the power receiving device (30) and a power receiving capability of the power receiving device; Equipped with The first power is weaker than the second power. A power transmission device (10).

[0174] (Appendix 2) The feedback information includes information on a reception result and information on a power receiving capability of the power receiving device, the means for determining the second power determines the second power by referring to the information on the reception result and the information on the power receiving capability; 2. The power transmitting device according to claim 1.

[0175] (Appendix 3) The power receiving capability includes the maximum value of the input power range. The means for determining the second power determines the second power such that the received power at the power receiving device does not exceed a maximum value when the power transmitting unit radiates a second power transmission beam having the second power set thereto. 3. The power transmitting device according to claim 2.

[0176] (Appendix 4) The power receiving capability further includes a minimum value of an input power range; the means for determining the second power determines the second power so that the received power at the power receiving device falls within the input power range when the power transmitting unit radiates a second power transmission beam having the second power set thereto. 4. The power transmitting device according to claim 3.

[0177] (Appendix 5) The information on the reception result includes information on a reference voltage detected in the power receiving device, The control unit further includes a means for deriving an estimated received power in the power receiving device by referring to information related to the reference voltage; The means for determining the second power determines the second power by referring to the estimated received power and the information on the power receiving capability. 3. The power transmitting device according to claim 2.

[0178] (Appendix 6) The power receiving capability includes the maximum value of the input power range. The means for determining the second power determines the second power such that the received power at the power receiving device does not exceed a maximum value when the power transmitting unit radiates a second power transmission beam having the second power set thereto. 6. The power transmitting device according to claim 5.

[0179] (Appendix 7) The power receiving capability further includes a minimum value of an input power range; the means for determining the second power determines the second power so that the received power at the power receiving device falls within the input power range when the power transmitting unit radiates a second power transmission beam having the second power set thereto. 7. The power transmitting device according to claim 6.

[0180] (Appendix 8) The information on the reception result includes information on the reception power of the first power transmission beam at the power receiving device, the control unit determines the second power by referring to the information on the received power and the information on the power receiving capability. 3. The power transmitting device according to claim 2.

[0181] (Appendix 9) The information on the power receiving capability includes a maximum value of an input power range, The means for determining the second power determines the second power such that the received power at the power receiving device does not exceed a maximum value when the power transmitting unit radiates a second power transmission beam having the second power set thereto. 9. The power transmitting device according to claim 8.

[0182] (Appendix 10) The information about the power receiving capability further includes a minimum value of an input power range; the means for determining the second power determines the second power so that the received power at the power receiving device falls within the input power range when the power transmitting unit radiates a second power transmission beam having the second power set thereto. 10. The power transmitting device according to claim 9.

[0183] (Appendix 11) The feedback information includes information regarding a power ratio calculated with reference to a reception result and a power receiving capability, The means for determining the second power determines the second power by referring to the information on the power ratio. 2. The power transmitting device according to claim 1.

[0184] (Appendix 12) The power transmitting device includes a control unit (32) that controls a power receiving unit (35) that receives a power transmission beam radiated from the power transmitting device (10), and the control unit A means (S131, S131a) for transmitting information regarding the power receiving capacity of the power receiving unit to the power transmitting device (10); A means (S131, S131a) for transmitting information on a reception result at a power receiving unit of a first power transmission beam radiated from the power transmitting device to the power transmitting device; Equipped with after transmitting the information on the power receiving capability and the information on the reception result, the power receiving unit receives a second power transmission beam having a power level higher than that of the first power transmission beam from the power transmitting device; A power receiving device (30).

[0185] (Appendix 13) The power transmitting device includes a control unit (32) that controls a power receiving unit (35) that receives a power transmission beam radiated from the power transmitting device (10), and the control unit A means (S133) for determining a power ratio by referring to a reception result at the power receiving unit of the first power transmission beam radiated from the power transmitting device and information related to the power receiving capacity of the power receiving unit; A means (S131b) for transmitting information regarding the power ratio to the power transmitting device; Equipped with After transmitting the information on the power ratio, the power receiving unit receives a second power transmission beam having a power level higher than that of the first power transmission beam from the power transmitting device. A power receiving device (30). [Explanation of symbols]

[0186] 1: Wireless power supply system 10: Power transmission equipment 11:Storage device 12: Processor 13: Input / Output Interface 14: Communication interface 15: Power transmission section 16: Input device 17: Output device 30: Power receiving device 31:Storage device 32 : Processor 33: Input / Output Interface 34: Communication interface 35: Power receiving section 36: Input device 37: Output device 151: Antenna 351: Antenna

Claims

1. The power transmitting device includes a control unit that controls a power transmitting unit that transmits power wirelessly. The control unit includes: a means for causing the power transmitting unit to radiate a first power transmission beam having a first power set thereto; A means for acquiring feedback information regarding a reception result of the first power transmission beam in a power receiving device; A means for identifying a power receiving capability of the power receiving device; a means for determining a second power that is usable in wireless power feeding to the power receiving device and is greater than the first power, by referring to the power receiving capability and the reception result; Equipped with The power receiving capability includes a maximum value and a minimum value of an input power range of the power receiving device, The power supply control device further includes a means for notifying the power receiving device or a user that power supply to the power receiving device is not possible when the second power is maximized but falls below the minimum value. Power transmission equipment.

2. The power transmitting device includes a control unit that controls a power transmitting unit that transmits power wirelessly. The control unit includes: a means for causing the power transmitting unit to radiate a first power transmission beam having a first power set thereto; A means for acquiring feedback information regarding a reception result of the first power transmission beam in a power receiving device; A means for identifying a power receiving capability of the power receiving device; a means for determining a second power that is usable in wireless power feeding to the power receiving device and is greater than the first power, by referring to the power receiving capability and the reception result; Equipped with The power receiving capability specifying means specifies at least a minimum value and a maximum value of an input power range of the power receiving device; the means for identifying the power receiving capacity identifies the power receiving capacity by referring to information acquired by reading a code attached to the power receiving device or a cover covering the power receiving device with a camera; the means for determining the second power determines the second power so that a received power at the power receiving device falls within the input power range when the power transmitting unit radiates a second power transmission beam having the second power set thereto. Power transmission equipment.

Images