Spatial power transmission system

Abstract

The present disclosure is a controller connected to a wireless communication device, which performs communication with a power reception device and supplies power to the power reception device, and a power transmission device, which spatially transmits power to the power reception device, wherein: a power supply area of the power transmission device overlaps at least part of a communication area of the wireless communication device; and the controller determines a movement destination for the power reception device, selects the wireless communication device or the power transmission device in accordance with the movement destination for the power reception device, and causes the selected wireless communication device or power transmission device to supply power to the power reception device.

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 Internet of Things (IoT) 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. Because the power transmitters have high transmission output power, 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] The present disclosure provides a spatial power transmission system including a wireless communication device that communicates with a power receiving device and transmits power to the power receiving device through space, a power transmitting device that supplies power to the power receiving device, and a controller as disclosed herein, wherein a power supply area of ​​the power transmitting device overlaps with at least a portion of a communication area of ​​the wireless communication device.

[0007] A controller according to the present disclosure is connected to a wireless communication device and a power transmission device, and executes a power supply method according to the present disclosure. In the power supply method according to the present disclosure, the controller determines a destination of the power receiving device, selects the wireless communication device or the power transmission device according to the destination of the power receiving device, and causes the selected wireless communication device or the power transmission device to supply power to the power receiving device.

[0008] When the destination of the power receiving device is an area where power can be supplied by a plurality of the power transmission devices, the controller may select the power transmission device located close to an extension of the direction of movement.Furthermore, when the destination of the power receiving device is close to the wireless communication device, the controller may select the wireless communication device.

[0009] 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.

[0010] 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.

[0011] The above disclosures can be combined as much as possible.

[0012] According to the present disclosure, power can be supplied from the power transmitting device when the power receiving device is located in the power supply area of ​​the power transmitting device, thereby enabling efficient power supply to a moving power receiving device.

[0013] 1 shows an example of a system configuration of the present disclosure; 2 shows an example of a terminal configuration; 3 shows an example of a controller configuration; 4 shows an example of a power supply method executed by the controller; 5 shows an example of a power supply method executed by the controller; 6 shows an explanatory diagram showing an example of an operation of the system of the present disclosure; 7 shows an example of an intermittent operation; 8 shows an explanatory diagram showing an example of an operation of the system of the present disclosure; 9 shows an example of a position determination method executed by the controller; 10 shows an example of a position determination method executed by the controller; 11 shows an example of a power supply method executed by the controller; 12 shows an example of a power supply method executed by the controller; 13 shows an example of an intermittent operation; 14 shows an example of an operation of the system of the present disclosure;

[0014] 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.

[0015] 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 terminal 94. The controller 93 is connected to the wireless communication device 91 and the power transmission device 92.

[0016] In this embodiment, the controller 93 performs beam control of the power transmitting device 92 in consideration of power transmission by the wireless communication device 91, rather than beam control that supplies power to all terminals 94 evenly.

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

[0018] The power transmitting device 92 is a device that transmits power over the air to the terminal 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 the device 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 environments where people are present. Such prohibited areas, which prohibit people from entering, 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 A ９２ The second sensor 82 may be mounted on the power transmission device 92. The first sensor 81 and the second sensor 82 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 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 ９２ The 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.

[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: - Time when the sensing data was set to be transmitted - Time when the sensing data was updated - Time when power was stored when power was supplied by the power transmission device 92 - Frequencies at which the receiver 11 can receive - Frequencies at which the power receiver 12 can receive - Frequencies at which the communication module 16 can transmit and receive

[0032] 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.

[0033] In this embodiment, the controller 93 determines whether to use the wireless communication device 91 or the power transmission device 92 to supply power based on the location information of the terminal 94. Furthermore, the power transmission devices 92#1 and 92#2 are capable of controlling the beam direction. The controller 93 controls the beam direction of the power transmission devices 92#1 and 92#2.

[0034] 4 shows an example of a power supply method executed by the controller 93. S11: The controller 93 acquires location information of the terminal 94. S12: The controller 93 determines which area the terminal 94 is located in. In this embodiment, the terminal 94 is located in Area A. ９２ An example where the terminal 94 is #1 is shown below. S13: The controller 93 determines the destination of the terminal 94.

[0035] S15: The destination of the terminal 94 is area A, which is far from the wireless communication device 91 ９２ If the movement is within #1, the controller 93 sets the beam direction of the power transmitting device 92#1 to the terminal 94. This allows the power transmitting device 92#1 to supply power to the terminal 94.

[0036] S31: The destination of the terminal 94 is far away from the wireless communication device 91, and it is in area A. ９２When entering #2, the controller 93 selects the power transmission device 92#2. At this time, the controller 93 determines whether the power transmission device 92#2 is activated. If the power transmission device 92#1 is activated (Yes in S31), the process proceeds to step S33. S32: If the power transmission device 92#2 is not activated (No in S31), the controller 93 activates the power transmission device 92#2. S33: The controller 93 sets the beam direction of the power transmission device 92#2 to the terminal 94 based on the position information of the terminal 94. This allows power to be supplied to the terminal 94 from the power transmission device 92#2.

[0037] S34: When the destination of the terminal 94 is close to the wireless communication device 91, the controller 93 selects the wireless communication device 91. Area A ９２ Even within #1, the power that can be supplied from the wireless communication device 91 to a terminal 94 that is close to the wireless communication device 91 is relatively large. For this reason, the wireless communication device 91 is used instead of the power transmission device 92 for a terminal 94 that is close to the wireless communication device 91. This allows the power transmission devices 92#1 and 92#2 to be responsible for supplying power to terminals 94 in locations where the power supply from the wireless communication device 91 is weak.

[0038] In step S12, the terminal 94 is in area A. ９２ #1 and A ９２ When the terminal 94 is outside of area #2, the controller 93 determines that the wireless communication device 91 is to be used to supply power to the terminal 94. ９２ #1 or A ９２ When it is within #2, the controller 93 executes steps S31 to S33.

[0039] After steps S33 and S34, the controller 93 may execute the steps shown in Fig. 5. S41: The controller 93 ９２ S42: Determine whether the terminal 94 is present in Area A before movement. ９２ If the terminal 94 is present in Area A before the movement, the controller 93 continues to activate the power transmitting device 92#1. ９２If there is no terminal 94 in #1, the controller 93 stops the power transmitting device 92#1.

[0040] In this embodiment, the wireless communication device 91 is used for terminals 94 that are close to the transmission source of the wireless communication device 91, and the power transmission device 92 is used for terminals 94 that are far from the wireless communication device 91. This makes it possible to maximize the power obtained by directing the beam from the power transmission device 92 in a direction that covers as many terminals 94 as possible.

[0041] As shown in FIG. 6, the area A of the power transmitters 92#1 and 92#2 ９２ #1 and A ９２ #2 overlaps, and Area A ９２ The destination of the terminal 94 located at #1 is Area A ９２ When the terminal 94 moves to the direction of the beam of the power transmitter 92#1, the controller 93 may not make the beam of the power transmitter 92#1 follow the movement of the terminal 94, but may leave the power supply to the power transmitter 92#2, which is located close to the extension of the direction of the movement. This allows the power transmitter 92#1 to supply power to another terminal 94.

[0042] In this embodiment, for ease of understanding, an example in which there is one wireless communication device 91 and two power transmission devices 92 is shown, but the present disclosure is not limited to this. ９１ Three or more power transmitting devices 92 may be installed within area A. ９１ The controller 93 controls the beam direction of each power transmitting device 92 depending on the number of terminals 94 and the direction of movement.

[0043] 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. 7. 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.

[0044] 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.

[0045] 8 shows an example of a system configuration according to the present disclosure. 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.

[0046] 9 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 The controller 93 determines that the location of the terminal 94 is within area A #1. ９２#1 may be written to the memory 32. If the storage period when power was supplied by the 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 or not the storage time for the sensing data set for each terminal 94 has elapsed. If the storage time has elapsed (Yes in step S25), the controller 93 waits until the time to transmit the sensing data (S26).

[0047] 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.

[0048] 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.

[0049] 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.

[0050] Third Embodiment In the spatial power transmission system shown in Fig. 8, the power transmission devices 92#1 and 92#2 are capable of controlling the beam direction. ９２ #1 and A ９２ Based on the beam direction in #2, Area A ９２ #1 and A ９２ The location of terminal 94 within #2 is determined.

[0051] Specifically, in step S21 shown in FIG. 9, the controller 93 ９２ Area A in a specific beam direction of #1 ９２ Select #11.

[0052] In step S22, the controller 93 selects the area A. ９２The beam of the power transmitter 92#1 is controlled so that power is supplied to area A#11. At this time, power is not supplied from the power transmitter 92#2. ９２ Power is supplied from the power transmitter 92#1 only to the terminal 94 present in #11.

[0053] Area A ９２ The terminal 94 located in area #11 immediately stores power and transmits sensing data at the shortest interval determined for each terminal 94. ９２ The transmission interval of the sensing data from the terminal 94 located in area #11 is ９２ Area A of #1 ９２ The interval for transmitting sensing data from the terminal 94 located in the area other than #11 is shorter than the interval for transmitting sensing data from the terminal 94 located in the area other than #11. Therefore, by executing steps S23 to S25, the controller 93 determines whether the terminal 94 is located in area A. ９２ It can be determined that it is located at #11.

[0054] These steps S21 to S25 are performed in area A. ９２ This is performed sequentially for each area of ​​#1 determined by the beam direction. Area A ９２ When area #1 is divided into eight, steps S21 to S25 are performed eight times. ９２ It is possible to determine in which area of ​​#1 the terminal 94 is located.

[0055] In step S25, the terminal 94 is in area A. ９２ When the power transmitting device 92 is located in area A #11, the controller 93 reduces the beam diameter of the power transmitting device 92 #1. ９２ It may be determined in which area of ​​#11 the terminal 94 is located.

[0056] In this embodiment, the controller 93 switches the area defined by the beam direction from the power transmitting device 92#1, and ９２ The sensing data includes identification information such as the MAC address of the terminal 94, so that information on where each terminal 94 is located can be managed in the memory 32.

[0057] By using this mechanism, the controller 93 can grasp the position of the terminal 94 that does not have a function for measuring its own position while supplying power to the terminal 94. As a result, this embodiment can efficiently supply power to the terminal 94 that needs power while tracking it.

[0058] The present embodiment is not limited to two or more power transmission devices 92#1 and 92#2, and may be limited to only one power transmission device. Furthermore, the present embodiment is not limited to one wireless communication device 91, and may be limited to two or more wireless communication devices 91.

[0059] 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.

[0060] 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.

[0061] In this embodiment, the accurate positional relationship between the terminal 94 to be supplied with power, the wireless communication device 91, and the power transmission device 92 may be determined by combining wireless information (CSI, etc.) between the terminal 94 and the external access point with positional information about the external access point, the wireless communication device 91, and the power transmission device 92. This allows the controller 93 to supply power to the terminal 94 that is relatively far from the wireless communication device 91 by beam control of the power transmission device 92 based on the positional relationship of each device, thereby improving the power supply efficiency of the entire system.

[0062] As described above, the spatial power transmission system of the present disclosure can achieve efficient wireless power transmission even during times when people are working or in large spaces (factories or warehouses). Furthermore, the present disclosure can achieve wireless power transmission with higher efficiency than when a wireless communication device 91 and a power transmission device 92 are simply combined. Here, high efficiency refers to not only increasing the total power received by all terminals 94, but also equalizing the maximum and minimum power levels and providing fair power supply. Maximizing and equalizing total power can sometimes be achieved simultaneously, but sometimes cannot. Because the IoT terminals we are considering have different individual power needs, it is important to be able to do both.

[0063] 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 wireless communication device that communicates with a power receiving device and supplies power to the power receiving device, and a power transmission device that transmits power over space to the power receiving device, wherein the power supply area of ​​the power transmission device overlaps with at least a portion of the communication area of ​​the wireless communication device, and the controller determines a destination of the power receiving device, selects the wireless communication device or the power transmission device according to the destination of the power receiving device, and causes the selected wireless communication device or the power transmission device to supply power to the power receiving device.

2. The controller according to claim 1, wherein when the destination of the power receiving device is an area that can be powered by a plurality of the power transmitting devices, the controller selects the power transmitting device that is located closest to an extension of the direction of movement.

3. The controller according to claim 1, wherein the controller selects the wireless communication device when the destination of the power receiving device is close to the wireless communication device.

4. A spatial power transmission system comprising: a wireless communication device that communicates with a power receiving device and supplies power to the power receiving device; a power transmitting device that transmits power to the power receiving device through space; and a controller according to any one of claims 1 to 3.

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.

6. The spatial power transfer system according to claim 4, 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 wireless communication device that communicates with a power receiving device and supplies power to the power receiving device, and a power transmission device that transmits power over space to the power receiving device, wherein the power supply area of ​​the power transmission device overlaps with at least a portion of the communication area of ​​the wireless communication device, and the controller determines a destination of the power receiving device, selects the wireless communication device or the power transmission device according to the destination of the power receiving device, and causes the selected wireless communication device or the power transmission device to supply power to the power receiving device.

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