Spatial power transmission system

Abstract

In the present disclosure, a controller is connected to a power sending device capable of spatially transmitting power to at least one of a plurality of power reception devices. The controller: estimates the power states of the plurality of power reception devices by using a power generation model; determines, on the basis of a result of the estimation, a power reception device that requires power supply among the plurality of power reception devices; and instructs, on the basis of a result of the determination, the power sending device to supply power to the power reception device that requires power supply among the plurality of power reception devices.

Description

Space-type power transmission system

[0001] The present disclosure relates to a technology for supplying power to a large number of sensors using natural energy or the like in combination with wireless power supply without replacing batteries or connecting power cables.

[0002] In recent years, Society 5.0 has been proposed, aiming to realize a smart society by installing a huge number of IoT (Internet of Things) devices in various places in everyday spaces and using a wide variety of sensing data. Realizing Society 5.0 requires a huge number of IoT devices, and one of the problems is power supply to IoT devices. When using chemical batteries as a power source, it is difficult to utilize a large number of them due to various reasons, such as the cost of battery inspection and replacement, the environmental impact of battery production and disposal, and the shortage of rare resources such as rare metals used in batteries. Energy harvesting technology (hereinafter sometimes abbreviated as "EH"), which harvests energy from the surrounding environment and uses it as power, has attracted attention as a technology to solve this problem. Using EH technology eliminates the need for chemical batteries and enables semi-permanent use of IoT devices over their lifetime. Among EH technologies, wireless power transfer, which can provide stable power supply in various locations, and a hybrid system using EH as a power source for IoT devices are being investigated [see, for example, Non-Patent Document 1]. ].

[0003] On the other hand, systems using dedicated power transmitters that are not bound by wireless communication standards have been proposed. The power transmitters have high transmission output power, so they can supply power that reaches the reference power of a power receiving device such as an IoT terminal in a short time.

[0004] C. Fu et al. , “Throughput Maximization in Wireless Communication Systems Powered by Hybrid Energy Harvesting,” IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS, VOL. 41, NO. 11, NOVEMBER 2022.

[0005] However, because a power transmission device transmits power one-to-one to a small area using a directional beam, there is a problem that the number of power receiving devices that can be supplied with power is limited. Therefore, an object of the present disclosure is to utilize a power transmission device to enable efficient power supply to each power receiving device.

[0006] A spatial power transfer system according to the present disclosure includes a power transmitting device capable of transmitting power via space to at least one of a plurality of power receiving devices, and the controller according to the present disclosure.

[0007] A controller according to the present disclosure is connected to the power transmitting device and executes a power supply method according to the present disclosure, in which the controller estimates power states of the plurality of power receiving devices using a generated power model, determines which of the plurality of power receiving devices need to be supplied with power based on the result of the estimation, and instructs the power transmitting device to supply power to the power receiving devices that need to be supplied with power based on the result of the determination.

[0008] The spatial power transfer system of the present disclosure may include a wireless communication device capable of communicating with the plurality of power receiving devices and supplying power to the plurality of power receiving devices. A power supply area of ​​the power transmitting device overlaps at least a portion of a communication area of ​​the wireless communication device. In this configuration, the controller may use the generated power model to estimate a power state of the power receiving device when power is supplied by the wireless communication device.

[0009] The power transmitting device may be instructed to supply power to a power receiving device that requires power supply before the power transmitting device is unable to supply power due to a person entering a prohibited area defined by the power transmitting device.

[0010] The power transmitting device may supply power to the power receiving device using radio waves having at least one of a frequency and intensity different from those of the wireless communication device, or light having a frequency different from those of the wireless communication device.

[0011] The power receiving device may include a power receiver that receives power from the power transmitting device, a receiver that converts a wireless signal from the wireless communication device into power, an energy source that generates power, a capacitor that stores power from the power receiver, the receiver, and the energy source, and a communication module that transmits data using the power stored in the capacitor. In this case, the controller uses the generated power model to estimate a power state stored in the capacitor.

[0012] The above disclosures can be combined as much as possible.

[0013] According to the present disclosure, a power receiving device that requires power supply is selected and power is supplied from a power transmitting device, so that power can be efficiently supplied to each power receiving device.

[0014] 1 is an example of a system configuration of the present disclosure; FIG. 2 is an example of a terminal configuration; FIG. 3 is an example of a controller configuration; FIG. 4 is a flow diagram showing an example of the operation of the controller; FIG. 5 is an explanatory diagram of intermittent operation; FIG. 6 is an example of a system configuration of the present disclosure; FIG. 7 is an example of a position determination method executed by the controller; FIG. 8 is an example of power generated in the terminal; FIG. 9 is an example of power generated in the terminal.

[0015] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below. These implementation examples are merely illustrative, and the present disclosure can be implemented in various forms with various modifications and improvements based on the knowledge of those skilled in the art. Note that components with the same reference numerals in this specification and drawings indicate the same components.

[0016] 1 shows an example of a system configuration according to the present disclosure. The spatial power transfer system of this embodiment includes a wireless communication device 91, a power transmission device 92, a controller 93, and a plurality of terminals 94. The controller 93 is connected to the wireless communication device 91 and the power transmission device 92.

[0017] The wireless communication device 91 is a device capable of wireless communication with a plurality of terminals 94, and may be, for example, a Wi-Fi access point or a base station. In the present disclosure, the wireless communication device 91 also supplies power to the terminals 94.

[0018] The power transmitting device 92 is a device that transmits power over the air to a plurality of terminals 94. In this embodiment, an example is shown in which two power transmitting devices 92#1 and 92#2 are provided. The power transmitting devices 92#1 and 92#2 each transmit power over the air to an area A defined for itself. ９２ #1 and Area A ９２ Supply power to #2. Area A ９２ #1 and Area A ９２ #2 indicates a power supply area to which the power transmitters 92#1 and 92#2 can supply power.

[0019] Area A, which is the power supply area of ​​the power transmitter 92 ９２ is the communication area of ​​the wireless communication device 91, ９１ In this embodiment, the area A to which the power transmission device 92 can supply power overlaps at least a part of the area A. ９２ indicates area A in which the wireless communication device 91 can communicate. ９１ In this embodiment, the area A ９１ Area A inside ９２ are placed multiple times.

[0020] Some power transmission devices, such as the power transmission devices 92#1 and 92#2, cannot be used in an environment where people are present. This prohibited area can be set to any range that is equal to or greater than the range of the beams from the power transmission devices 92#1 and 92#2. In this embodiment, Area A ９２ This shows an example in which the area is set as a prohibited area where people are prohibited from entering.

[0021] The spatial power transmission system of the present disclosure is ９１ and A ９２ For example, the controller 93 is provided with a means for notifying an intrusion into Area A. ９１ a first sensor 81 for detecting an intrusion into area A; ９２ The second sensor 82 detects an intrusion into area A. ９２ #1 and A９２ The second sensor 82 may be mounted on the power transmission device 92. The first sensor 81 and the second sensor may notify periodically or only when information is updated.

[0022] The first sensor 81 and the second sensor 82 may be any means capable of detecting a person, such as a human presence sensor. ９１ When the area A is large, a plurality of first sensors 81 are used to measure the area A ９１ Regarding the second sensor 82, a plurality of second sensors 82 may be used to detect an intrusion into area A. ９２ Intrusion into Area A #1 may be detected. ９１ and A ９２ The means for notifying an intrusion into the room may be entry / exit management information such as a card key.

[0023] The terminal 94 is a power receiving device that stores power and transmits data such as sensing data when the stored power reaches a reference power, and is, for example, an IoT (Internet of Things) terminal. The terminal 94 is an EH hybrid wireless terminal that operates using power supplied by the wireless communication device 91, power supplied by the power transmission device 92, and power supplied from other power sources.

[0024] 2 shows an example configuration of the terminal 94. The terminal 94 includes a receiver 11, a power receiver 12, and an energy source 17. The receiver 11 has a function of converting a wireless signal from a wireless communication device 91 into electric power. The power receiver 12 has a function of receiving electric power from a power transmission device 92. The energy source 17 has a function of generating electric power, such as solar power generation. The capacitor 13 has a function of storing electric power from the receiver 11, the power receiver 12, and the energy source 17.

[0025] The terminal 94 includes a microcomputer 14, a sensor 15, and a communication module 16. The sensor 15 is any sensor, such as a camera or a microphone, that is defined for each terminal 94. The communication module 16 has a function of transmitting and receiving data to and from any device, such as a server. The microcomputer 14 has a function of controlling the sensor 15 and the communication module 16. The microcomputer 14 may also have a function of controlling the receiver 11, the power receiver 12, and the energy source 17.

[0026] The sensor 15 may include a sensor capable of detecting a position, such as a GPS (Global Positioning System), and the sensing data may include position information of the terminal 94. Furthermore, the communication module 16 may transmit and receive data other than the sensing data.

[0027] The microcomputer 14, the sensor 15, and the communication module 16 operate using the power stored in the capacitor 13. When power is stored in the capacitor 13, the sensor 15 acquires sensing data, and the communication module 16 transmits the sensing data. The transmitted sensing data is collected in a predetermined server (not shown) via an external access point 83. The sensing data may include wireless information such as CSI (Channel State Information).

[0028] The external access point 83 is an access point that transfers sensing data, and can be an access point with low power consumption such as BLE (Bluetooth Low Energy) or LPWA (Low Power Wide Area).

[0029] 3 shows an example of the configuration of the controller 93. The controller 93 includes a processor 31, a memory 32, and a communication module 33. The memory 32 stores location information of each terminal 94, area A, ９１ and A ９２The processor 31 has a function of controlling the wireless communication device 91 and the power transmission device 92 based on the information stored in the memory 32. The controller 93 may be realized by the processor executing a software program stored in the memory 32.

[0030] The memory 32 stores any information used by the controller 93. For example, the following can be exemplified: (i) location information of each terminal 94; (ii) area A; ９１ and A ９２ (iii) Information about human intrusion into the terminal; (iv) Communication frequency and power supply frequency of the wireless communication device 91; and (v) Transmission frequency of the power transmission device 92.

[0031] The terminal internal information stores information on sensing data of each terminal 94 linked to the identification information of each terminal 94. Examples of sensing data information include the following: - The set time for sending the sensing data - The time when the sensing data was updated - The power storage time when power is supplied by the power transmission device 92 - The frequencies at which the receiver 11 can receive - The frequencies at which the power receiver 12 can receive - The frequencies at which the communication module 16 can transmit and receive

[0032] The terminal internal information may further include the following information: The sensing data itself Information transmitted together with the sensing data (time, identifier of the terminal 94, location of the terminal 94, etc.)

[0033] The terminal internal information may further include a generated power model for each terminal 94. The generated power model includes, for example, the following information: Power generated by the energy source 17 Power generated by the terminal 94 when power is supplied by the wireless communication device 91 Power generated by the terminal 94 when power is supplied by the power transmission device 92 Reference power P required for the terminal 94 to transmit sensing data Parameters used in the generated power model, such as weather information.

[0034] The method for acquiring the location information of each terminal 94 is arbitrary, and examples include the following: Each terminal 94 transmits its own location information to the controller 93. The location information included in the sensing data is acquired. The tag provided on the terminal 94 is read. The methods described in the second and third embodiments are used.

[0035] In this embodiment, the controller 93 executes the power supply method of the present disclosure. In the power supply method of the present disclosure, the controller 93 estimates the power state of the terminal 94 using a generated power model (S1), determines the terminal 94 that needs to be powered based on the result of the estimation (S2), and instructs the power transmission device 92 to supply power to the terminal 94 that needs to be powered based on the result of the determination (S3).

[0036] The generated power model is a model of the state of power stored in the capacitor 13. For example, the generated power model is a generated power model of power supplied to the energy source 17, configured using arrival time information and reference power information of the sensing data transmitted by each terminal 94, terminal position information, and weather information. In this embodiment, the generated power model is not limited to the power supplied to the energy source 17, but also includes the power generated by the terminal 94 when power is supplied by the wireless communication device 91 and the power generated when power is supplied by the power transmission device 92.

[0037] The controller 93 determines the terminal 94 that needs to be powered based on the estimated power state of each terminal 94. Then, the controller 93 controls the beam directions of the power transmitters 92#1 and 92#2 so as to supply power to the terminal 94 that needs to be powered.

[0038] The generated power model may be created by the controller 93, or may be created by another device and stored in the memory 32. By providing the controller 93 with a function for creating a generated power model, the generated power model can be updated as needed, thereby improving prediction accuracy. If there are no fluctuations in the generated power model, the generated power model created by another device can be stored in the memory 32, thereby reducing the processing required of the controller 93.

[0039] An example of the operation of the controller 93 will be described with reference to FIG. 4. S11: Using the generated power model, the power state of the terminal 94 is calculated. At this time, the power state of the terminal 94 at the scheduled time of transmitting the sensing data can be calculated. S12: It is determined whether the calculated power state reaches the reference power. If the reference power is reached (Yes in S12), the processing ends. If the reference power is not reached (No in S12), the process proceeds to step S13. S13: It is determined whether the power stored in the capacitor 13 by the scheduled time of transmitting the sensing data will reach the reference power as a result of power supply by the wireless communication device 91. S14: If it is determined that the reference power will be reached in step S13, the wireless communication device 91 is caused to supply power to the terminal 94. S15: If it is determined that the reference power will not be reached in step S13, information on the person's work location and time is obtained from the memory 32, and area A of the power transmission device 92 where the terminal 94 is located is calculated. ９２ S17: Determine whether or not a person is present in Area A #1. ９２ When a person is present in area #1 (Yes in S15), ９２ Warning to get out of #1. S18: Area A ９２ If no person is present at #1 (No in S15), the power transmitting device 92 is caused to supply power to the terminal 94.

[0040] In step S17, the controller 93 does not issue a warning and ９２ For example, it may wait until there are no people in Area A #1. ９２ The power transmitting device 92 may be caused to supply power to the terminal 94 when there is no one in #1.

[0041] The spatial power transfer system of the present disclosure can use the generated power model to predict the power state of each terminal 94, and can therefore accurately determine which terminals 94 require power supply. As a result, the system of the present disclosure can achieve highly efficient wireless power supply.

[0042] Furthermore, in the present disclosure, since the generated power is predicted in advance, when the power supply to the terminal 94 is insufficient, ９２On the other hand, when the power of the terminal 94 is sufficiently supplied by the EH, the power transmitting device 92 can be operated by prohibiting people from entering or leaving the area A. ９２ This allows the present disclosure to simultaneously perform work involving human intervention and constantly satisfy the requirements of the terminal 94.

[0043] If the time for human intervention is set or if the reference power of the terminal 94 cannot be met even if the power transmitting device 92 is moved, the beam and supply power of the power transmitting device 92 are adjusted so that the reference power is reached just before the human intervention or just before the generated power decreases. This allows the terminal 94 to transmit sensing data even if the generated power by the EH decreases.

[0044] As described above, the present disclosure makes it possible to increase the time during which the reference power of the IoT terminal 94 is satisfied while also enabling work that requires human intervention. Therefore, the present disclosure makes it possible to increase the time during which a required intermittent operation cycle is satisfied.

[0045] Second Embodiment A terminal 94 that cannot operate until power is stored in the capacitor 13 performs intermittent operation that alternates between a power storage period and a power consumption period, as shown in Fig. 5. During the power storage period, power is stored in the capacitor 13 from the receiver 11, the power receiver 12, and the energy source 17. During the power consumption period, the sensor 15 acquires sensing data, and the communication module 16 transmits the sensing data.

[0046] The power supplied by the power transmission device 92 is greater than the power supplied by the wireless communication device 91. Therefore, the power storage period of the terminal 94 supplied with power by the power transmission device 92 is shorter than that of the terminal 94 supplied with power by the wireless communication device 91. This difference in the power storage period is reflected in the transmission interval of the sensing data. In this embodiment, the controller 93 determines the position of the terminal 94 based on the transmission interval of the sensing data.

[0047] 6 shows an example of a system configuration of this embodiment. The spatial power transmission system of this embodiment includes a power transmission device 92 and a controller 93. The power transmission device 92 is a device that transmits power through space to a terminal 94. In this embodiment, an example is shown in which two power transmission devices 92#1 and 92#2 are provided. The power transmission devices 92#1 and 92#2 each transmit power through space to an area A defined for itself. ９２ #1 and Area A ９２ Power #2.

[0048] 7 shows an example of a position determination method executed by the controller 93. S21: Area A ９１ and A ９２ Select an area with no people in it. For example, Area A ９２ When there is no one in area #1, the controller 93 ９２ S22: The controller 93 selects the selected area A. ９２ Power is supplied from the power transmitter 92#1 in area A. At this time, power is not supplied from the power transmitter 92#2. ９２ Since the terminal 94 located in area #1 immediately stores power, the sensing data is transmitted at the shortest interval determined for each terminal 94. S23: The controller 93 determines whether the sensing data transmitted from the terminal 94 has been updated. S24: If the sensing data has been updated, the controller 93 compares it with the transmission time of the sensing data set for the terminal 94 whose sensing data has been updated. If it corresponds to the storage period when power was supplied by the power transmission device 92 #1, the position of the terminal 94 is determined to be in area A. ９２ If the storage period when power was supplied by power transmission device 92 #1 has elapsed, the process returns to step S21. S25: If the sensing data has not been updated in step S23, the controller 93 determines whether the sensing data is within the storage time set for each terminal 94. If the storage time is within the storage time (Yes in step S25), the controller 93 waits until the time to transmit the sensing data (S26).

[0049] In step S25, if the accumulation time has elapsed (No in step S25), ９２ Since there is no terminal 94 in #1, the process returns to step S21. ９２ Change to #2.

[0050] In this embodiment, an example in which there are two power transmitters 92 is shown, but there may be three or more power transmitters 92.

[0051] As described above, the controller 93 of this embodiment can grasp the location of the terminal 94 that does not have a function for measuring its own location. In particular, since the sensing data includes identification information such as the MAC address of the terminal 94, information on the location of each terminal 94 can be managed in the memory 32.

[0052] (Third embodiment) In this embodiment, an example of power supply to a terminal 94 that performs intermittent operation will be described. Fig. 8 shows an example of power generated in three terminals 94#1, 94#2, and 94#3. In the figure, the generated power indicates the power stored in the capacitor 13. ２ From t ４ Therefore, the power transmitting device 92 cannot be used during the operation time t １ After transmitting the sensing data, the next sensing data is scheduled to be transmitted at time t ３ Even if the power stored in the capacitor 13 reaches the reference power P, the power stored in the capacitor 13 may not reach the reference power P. ９２ #1 and A ９２ Power is supplied taking into account the work time at #2.

[0053] Specifically, the controller 93 acquires information about the work location and time of the person, and ９２ #1 and A ９２ Before the work period at #2, power is supplied to the terminal 94 using the power transmission devices 92#1 and 92#2. The method of determining whether to supply power to the terminal 94 is as described in the first embodiment.

[0054] For example, as shown in FIG. 9, the controller 93 ６From time t １ The controller 93 supplies power to the terminal 94#3 using the power transmission device 92 until the end of the work period. At this time, the controller 93 supplies power to the terminal 94#3 in an amount corresponding to the number of times sensing data is to be transmitted during the work period. For example, the terminal 94#3 is powered by the power transmission device 92 until the end of the work period t ４ At time t １ and t ３ The controller 93 transmits the sensing data twice. At this time, the controller 93 instructs the power transmitting device 92#1 or 92#2 to store twice the reference power P in the capacitor 13 of the terminal 94#3. This embodiment makes it possible to adjust the power supply so that intermittent operation is performed even with a small amount of generated power during the working period. Therefore, this embodiment makes it possible to satisfy the intermittent operation cycle at all times.

[0055] Other Embodiments The controller 93 of the present disclosure can also be realized by a computer and a program, and the program can be recorded on a recording medium or provided via a network.

[0056] Furthermore, this embodiment is not limited to a hybrid of the wireless communication device 91 and the power transmission device 92. For example, the power transmission device 92 may use radio waves that are different in at least one of frequency and intensity from those of the wireless communication device 91. Furthermore, the power transmission device 92 may use other power transmission methods such as optical wireless power transmission. By employing optical wireless power transmission, power can be supplied even in environments where there are restrictions on the use of radio waves.

[0057] 11: Receiver 12: Power receiver 13: Capacitor 14: Microcomputer 15: Sensor 16: Communication module 81: First sensor 82: Second sensor 83: External access point 91: Wireless communication device 92: Power transmission device 93: Controller 94: Terminal

Claims

1. A controller connected to a power transmitting device capable of spatially transmitting power to at least one of a plurality of power receiving devices, the controller estimating the power states of the plurality of power receiving devices using a generated power model, determining which of the plurality of power receiving devices needs to be supplied with power based on the result of the estimation, and instructing the power transmitting device to supply power to the power receiving device that needs to be supplied with power based on the result of the determination.

2. The controller of claim 1, which instructs the power transmitting device to supply power to a power receiving device that requires power supply before the power transmitting device is unable to supply power due to a person entering a prohibited area defined by the power transmitting device.

3. A spatial power transmission system comprising: a power transmitting device capable of transmitting power via space to at least one of a plurality of power receiving devices; and the controller according to claim 1 or 2.

4. The spatial power transmission system of claim 3, further comprising a wireless communication device capable of communicating with and supplying power to the plurality of power receiving devices, wherein the power transmission area of ​​the power transmitting device overlaps with at least a portion of the communication area of ​​the wireless communication device, and the controller uses the generated power model to estimate the power state of the power receiving device when power is supplied by the wireless communication device.

5. The spatial power transmission system according to claim 4, wherein the power receiving device comprises: a power receiver that receives power from the power transmitting device; a receiver that converts a wireless signal from the wireless communication device into power; an energy source that generates power; a capacitor that stores power from the power receiver, the receiver, and the energy source; and a communication module that transmits data using the power stored in the capacitor; and wherein the controller uses the generated power model to estimate the state of power stored in the capacitor.

6. The spatial power transfer system according to claim 3, wherein the power transmitting device supplies power to the power receiving device using radio waves having at least one of a frequency and intensity different from that of the wireless communication device, or light having a frequency different from that of the wireless communication device.

7. A power supply method executed by a controller connected to a power transmission device capable of spatially transmitting power to at least one of a plurality of power receiving devices, wherein the controller estimates the power states of the plurality of power receiving devices using a generated power model, determines which of the plurality of power receiving devices needs to be supplied with power based on the result of the estimation, and instructs the power transmission device to supply power to the power receiving device of the plurality of power receiving devices that needs to be supplied with power based on the result of the determination.

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