Spatial power transmission system

Abstract

In this spatial power transmission system, a controller is connected to a wireless communication device that communicates with a power reception device and supplies power to the power reception device, and a power transmission device that spatially transmits power to the power reception device. The power supply area of the power transmission device overlaps at least a part of the communication area of the wireless communication device. The controller causes the power transmission device to supply power to the power reception device when the power reception device is located in the power supply area, and causes the wireless communication device to supply power to the power reception device when the power reception device is located in the communication area outside the power supply area.

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] Since wireless power supply requires wireless resources, there is an upper limit to the amount of power that can be supplied. Therefore, a method for efficiently wirelessly supplying power to IoT terminals that require power supply using limited wireless resources is required.

[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] A power supply system using a dedicated power transmitter that is not bound by wireless communication standards has been proposed. Because the power transmitter has a high transmission output power, it can supply power that reaches the reference power of a power receiving device, such as an IoT terminal, in a short time. However, because the power transmitter uses a directional beam to transmit power one-to-one to a small area, there is a problem that the number of power receiving devices that can be supplied with power is limited.

[0006] The present disclosure aims to utilize a power transmission device to enable efficient power supply to each power receiving device.

[0007] A spatial power transmission system according to the present disclosure includes 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 the present disclosure, 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.

[0008] A controller of the present disclosure is connected to the wireless communication device and the power transmitting device, and executes a power supply method of the present disclosure. In the power supply method of the present disclosure, the controller causes the power transmitting device to supply power to the power receiving device when the power receiving device is located in the power supply area, and causes the wireless communication device to supply power to the power receiving device when the power receiving device is located within the communication area outside the power supply area.

[0009] The controller may be configured to cause the wireless communication device to supply power to the power receiving device when a person enters a prohibited area defined by the power transmitting device. The controller may be configured to start determining whether a person has entered the prohibited area when a person enters the communication area.

[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.

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

[0013] According to the present disclosure, since power is supplied to the power receiving devices using both the wireless communication device and the power transmitting device, it is possible to efficiently supply power to some of the power receiving devices using the power transmitting device, while evenly supplying power to the power receiving devices to be supplied using the wireless communication device. Therefore, the present disclosure makes it possible to utilize the power transmitting device to efficiently supply power to each power receiving device.

[0014] 1 shows an example of a system configuration according to the present disclosure; 2 shows an example of a configuration of a power receiving device; 3 shows an example of a configuration of a controller; 4 shows an example of an operation of the system according to the present embodiment; 5 shows an example of a power supply method executed by the controller; 6 shows an example of an intermittent operation; 7 shows an example of a system configuration according to the present disclosure; 8 shows an example of a position determination method executed by the controller;

[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 terminal 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 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 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 are used to measure the area A ９１ The second sensor 82 may also detect an intrusion into area A using a plurality of second sensors. 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 mobile power receiving device, such as an IoT terminal, and 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 a 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. In the present disclosure, an example is shown in which the energy source 17 is 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 to determine the power transmission device 92 that supplies power to the terminal 94. For example, the following can be exemplified: (i) location information of each terminal 94; (ii) area A; ９１ and A ９２ (iii) Information on the internal state of the device

[0031] The terminal internal information stores information on sensing data of each terminal 94 linked to identification information of the terminal 94. The sensing data information includes the time when the sensing data was set to be transmitted, the time when the sensing data was updated, and the time when power was stored when power was supplied by the power transmission device 92.

[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] An example of the operation of the system of this embodiment will be described with reference to FIG. ９２ When a terminal 94 is present in area A, the controller 93 supplies power to the terminal 94 using the power transmission device 92. ９２ The beam direction of the power transmitting device 92 is controlled so as to follow the movement of the terminal 94 within #1.

[0035] Area A ９２ Terminal 94 moves out of Area #1 and moves to Area A. ９２ When there is no wireless communication device 91 in area A, the controller 93 supplies power to the terminal 94 using the wireless communication device 91. ９１The wireless signal for power supply is transmitted to the entire area A. ９２ This may be done at any time while the terminal 94 is outside the network.

[0036] Terminal 94 moves to area A. ９２ When the terminal 94 is present in area A, the controller 93 supplies power to the terminal 94 using the power transmission device 92. ９２ The beam direction of the power transmitting device 92 is controlled so as to follow the movement of the terminal 94 within #2.

[0037] In this way, the spatial power transmission system of this embodiment can supply power to the terminal 94 using the wireless communication device 91 when the terminal 94 moves. ９２ When a person enters the building, the power transmission device 92 cannot be used. Therefore, the controller 93 executes the power supply method of the present disclosure.

[0038] In the power supply method of this embodiment, the controller 93 determines whether the terminal 94 is in area A. ９２ When the terminal 94 is located in area A, the power transmitting device 92 supplies power to the terminal 94. ９２ Area A outside ９１ When the terminal 94 is located within the predetermined range, the wireless communication device 91 is caused to supply power to the terminal 94. The spatial power transfer system of this embodiment executes steps S11 to S14 shown in FIG.

[0039] S11: The controller 93 determines whether the area A ９１ It is determined whether or not a person is present within Area A, which is a communication area. ９１ When a person enters Area A, which is a prohibited area, ９２ S12: Area A ９１ If there is no person in area A, the controller 93 ９２ S13: Determine whether or not a person is present in Area A. ９２ If a person is present in the area A, the controller 93 ９２ For example, the wireless communication device 91 supplies power to the terminal 94 in the area A. ９２If there is a person in area A #1, the controller 93 ９２ The power transmitting device 92#1 of #1 is stopped and the wireless communication device 91 is started. The wireless communication device 91 may be always running. S14: Area A ９２ If there is no person in the area A, the controller 93 ９２ The power transmitting device 92 supplies power to the terminal 94 in the area A. ９２ If no one is present in the power transmission device 92#2, the controller 93 activates the power transmission device 92#2. If the power transmission device 92#2 is already activated, power can be supplied as is.

[0040] The spatial power transmission system of this embodiment can provide a hybrid system that uses the wireless communication device 91 and the power transmission device 92 to supply power to the terminal 94. ９２ By using the wireless communication device 91 when the terminal 94 moves outside, wireless power transmission can be realized even during times when people are working or over a wide area within a warehouse / factory.

[0041] 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. 6. 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.

[0042] 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.

[0043] 7 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.

[0044] 8 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).

[0045] 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.

[0046] 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.

[0047] 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.

[0048] Third Embodiment In the spatial power transmission system shown in Fig. 7, 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.

[0049] Specifically, in step S21 shown in FIG. 8, the controller 93 ９２ Area A in a specific beam direction of #1 ９２ Select #11.

[0050] In step S22, the controller 93 selects the area A. ９２ The 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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 seamlessly switch to power supply from the wireless communication device 91 during human intervention or when the user moves out of the beam range of the power transmission device 92, thereby continuously executing wireless power transmission and providing a stable power supply to the IoT terminal for a long period of time.

[0060] 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 transmitting device that transmits power over space to the power receiving device, wherein the power supply area of ​​the power transmitting device overlaps with at least a portion of the communication area of ​​the wireless communication device, and the controller causes the power transmitting device to supply power to the power receiving device when the power receiving device is located in the power supply area, and causes the wireless communication device to supply power to the power receiving device when the power receiving device is located within the communication area outside the power supply area.

2. The controller according to claim 1, wherein the controller causes the wireless communication device to supply power to the power receiving device when a person enters a prohibited area defined by the power transmitting device.

3. The controller according to claim 2, wherein when a person enters the communication area, the controller starts determining whether a person has entered the prohibited area.

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 via space to the power receiving device; 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 transmitting device that transmits power over space to the power receiving device, wherein the power supply area of ​​the power transmitting device overlaps with at least a portion of the communication area of ​​the wireless communication device, and the controller causes the power transmitting device to supply power to the power receiving device when the power receiving device is located in the power supply area, and causes the wireless communication device to supply power to the power receiving device when the power receiving device is located within the communication area outside the power supply area.

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