Optical wireless power supply system, receiving device, transmitting device, control device, control method, and program

The described system addresses inefficient power extraction in optical wireless power supply by using a grid-configured light source and photoelectric conversion unit, disconnecting underperforming cells, and adjusting laser output, resulting in efficient and stable power generation.

JP7845496B2Active Publication Date: 2026-04-14NIPPON TELEGRAPH & TELEPHONE CORP
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
NIPPON TELEGRAPH & TELEPHONE CORP
Filing Date
2022-11-10
Publication Date
2026-04-14

AI Technical Summary

Technical Problem

In optical wireless power supply technology, using a multi-cell type photoelectric conversion unit results in inefficient electric power extraction due to uneven light distribution and atmospheric disturbances, leading to limited current values and energy loss.

Method used

A system with a light source unit and photoelectric conversion unit arranged in a grid configuration, where cells are connected in series, and cells not receiving sufficient light are disconnected from the series connection, with corresponding laser output reduction.

Benefits of technology

Enables efficient power extraction by ensuring uniform beam irradiation, reducing energy loss, and preventing heat generation, thereby enhancing power generation efficiency and stability.

✦ Generated by Eureka AI based on patent content.

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Abstract

This optical wireless power supply system comprises: a light source unit provided with a plurality of light source elements; and a photoelectric conversion unit provided with a plurality of photoelectric conversion elements. A light-emitting surface of the light source unit and a light-receiving surface of the photoelectric conversion unit are arranged to face each other. The arrangement of the plurality of photoelectric conversion elements on the light-receiving surface is the same as the arrangement of the plurality of light source elements on the light-emitting surface.
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Description

Technical Field

[0001] The present invention relates to optical wireless power supply technology.

Background Art

[0002] In optical wireless power supply technology, for example, a laser is used as an energy medium. Laser light (also called a laser beam) is transmitted from the laser toward the power supply target, and at the power supply target, the laser light is converted into electric power using a photoelectric conversion element such as a solar cell. Here, the light source (light source element) that outputs the laser light is called a "laser". The "laser" may be called a laser medium, a laser oscillator, or the like.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In optical wireless power supply technology, in order to supply sufficient power to the power supply target, it is assumed that a multi-cell type photoelectric conversion unit having a configuration in which a plurality of cells (photoelectric conversion elements) are connected is used on the receiving side of the laser light. However, in the prior art, when a multi-cell type photoelectric conversion unit is used, there is a problem that electric power cannot be efficiently extracted from light.

[0005] The present invention has been made in view of the above points, and an object thereof is to provide a technology that enables efficient extraction of electric power from light in optical wireless power supply technology.

Means for Solving the Problems

[0006] According to the disclosed technology, a light source unit including a plurality of light source elements, A photoelectric conversion unit comprising multiple photoelectric conversion elements, The light-emitting surface of the light source unit and the light-receiving surface of the photoelectric conversion unit are arranged opposite each other, and the arrangement of the plurality of photoelectric conversion elements on the light-receiving surface is the same as the arrangement of the plurality of light source elements on the light-emitting surface. A wireless optical power transfer system, The aforementioned multiple photoelectric conversion elements are connected in series, and any photoelectric conversion element that satisfies predetermined voltage conditions is disconnected from the series connection, and the output intensity of the light source element corresponding to the photoelectric conversion element disconnected from the series connection is reduced. A wireless optical power supply system will be provided. [Effects of the Invention]

[0007] According to the disclosed technology, a technology is provided that enables efficient power extraction from light in optical wireless power transmission technology. [Brief explanation of the drawing]

[0008] [Figure 1] This is a diagram to explain the problem. [Figure 2] This is a diagram to explain the problem. [Figure 3] This is a configuration diagram of an optical wireless power transmission system according to an embodiment of the present invention. [Figure 4] This is a diagram showing the configuration of the transmitting device 100. [Figure 5] This is a diagram showing the configuration of the receiving device 200. [Figure 6] This figure shows an example of cell arrangement. [Figure 7] This is a diagram showing the configuration of the control device 300. [Figure 8] This is a diagram illustrating the operation of an optical wireless power transmission system. [Figure 9] This is a diagram to explain cell numbering. [Figure 10] This is a diagram to explain the numbering system for lasers. [Figure 11] This is a diagram illustrating the operation of an optical wireless power transmission system. [Figure 12] This is a diagram illustrating the operation of an optical wireless power transmission system. [Figure 13] This is a diagram showing the configuration of the photoelectric conversion unit 210. [Figure 14] It is a configuration diagram of the photoelectric conversion unit 210. [Figure 15] It is a flowchart showing an operation example of the control device 300. [Figure 16] It is a diagram showing an example of the hardware configuration of the device.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention (hereinafter referred to as "the present embodiments") will be described with reference to the drawings. The embodiments described below are merely examples, and the embodiments to which the present invention is applied are not limited to the following embodiments.

[0010] In the embodiments described below, it is assumed that a laser is used as the light source in the transmission device, but using a laser as the light source is merely an example. The light sources to which the technology according to the present invention can be applied are not limited to a specific type of light source. Any light source that can output light (electromagnetic waves from infrared to ultraviolet) may be used. Hereinafter, those that output light may be referred to as "light source elements" or "light source units" in some cases. As described above, the light source is not limited to a laser, but in the present embodiments, it is preferable to use a laser as the light source.

[0011] Hereinafter, first, the problems related to the technology of the present embodiments will be described in detail, and then the technology of the present embodiments will be described. Note that the content of the description of the following problems is not publicly known.

[0012] (Regarding the problems) Generally, the beam output from a laser (which may also be called an optical beam, beam light, etc.) is called a Gaussian beam, and the intensity distribution of light in a plane perpendicular to the optical axis is a Gaussian distribution.

[0013] In optical wireless power transmission technology, there are two types of photoelectric conversion units that convert received light into electricity: single-cell types, which have only one photoelectric conversion element (cell), and multi-cell types, which have multiple cells. The voltage that can be extracted from a single cell is determined by the size of the element's bandgap, and for a typical solar cell, it is 0.5V (Non-Patent Literature 1). Therefore, when trying to supply high power, the current value becomes large, making the single-cell type unsuitable.

[0014] On the other hand, in the case of a multi-cell type, the voltage can be increased by connecting the cells in series, thereby increasing the amount of power that can be extracted. However, if there is a cell among the multiple cells that does not receive enough light, the current value of that cell becomes a bottleneck, limiting the overall current value and preventing high power from being obtained. In addition, the light energy incident on the other cells cannot be extracted as power but is converted into heat, degrading the characteristics of the photoelectric conversion unit.

[0015] Referring to Figures 1 and 2, the aforementioned challenges when using a Gaussian beam will be explained in more detail.

[0016] In the configuration shown in Figures 1 and 2, the light source element, laser 1, and the photoelectric conversion unit 2, which receives light, are shown. For laser 1, the side 3 (emitting surface) on which the laser 1 emits light is also shown. For photoelectric conversion unit 2, the side that receives light (receiving surface) is shown. As shown in Figures 1 and 2, the photoelectric conversion unit 2 is equipped with multiple cells arranged in a grid. Also in Figures 1 and 2, the beam emitted from surface 3 is input to the optical path, so surface 3 is labeled as "input". Furthermore, the output from the optical path becomes the input to photoelectric conversion unit 2.

[0017] As mentioned above, the intensity distribution of the Gaussian beam follows a Gaussian distribution, making it difficult to uniformly illuminate each cell constituting the photoelectric conversion unit 2, as shown in Figure 1. Note that in the drawings of this application, the shape (intensity distribution) of the light source or light receiver of the Gaussian beam is an illustrative representation, not the actual intensity distribution, for illustrative purposes. In a Gaussian beam, according to the Gaussian distribution, the light is strongest in the center of a circular shape and weakens towards the periphery.

[0018] Furthermore, as shown in Figure 2, if laser 1 is used to emit laser light (beam) from a wider area in order to illuminate each cell as uniformly as possible, the beam will extend beyond the light-receiving surface of the photoelectric conversion unit 2, leading to increased losses and safety problems. In addition, atmospheric disturbances are expected to disrupt the beam and further cause an uneven distribution of intensity.

[0019] Atmospheric disturbances refer to disturbances in the air within the atmosphere. Vortices of varying sizes in the air create refractive index distributions, and when light such as laser beams propagates through the atmosphere, the wavefront becomes turbulent.

[0020] The following provides a detailed explanation of the system configuration and operation that solves the aforementioned problems.

[0021] (Example system configuration) Figure 3 shows an example configuration of the optical wireless power supply system in this embodiment. As shown in Figure 3, the optical wireless power supply system in this embodiment includes a transmitter 100, a receiver 200, and a control device 300. The transmitter 100 and the receiver 200 are each capable of communicating with the control device 300. The transmitter 100 and the receiver 200 may be connected to the control device 300 by wire or wirelessly. The control device 300 may also be provided within the receiver 200.

[0022] (Examples of each device configuration) Figure 4 shows an example of the configuration of the transmitting device 100. As shown in Figure 4, the transmitting device 100 includes a light source unit 110 and a light source control unit 120. In this embodiment, the light source unit 110 includes a structure in which a plurality of lasers (light source elements) are arranged in an array (which may also be described as a grid). The light source unit 110 may also be called a laser array, an array of lasers, etc.

[0023] The light source control unit 120 controls the output of each laser in the light source unit 110 (array laser) based on instructions (control signals) from the control device 300. In other words, it increases or decreases the intensity of the laser light being output.

[0024] Figure 5 shows an example of the configuration of the receiving device 200. As shown in Figure 5, the receiving device 200 includes a photoelectric conversion unit 210 and a switching control unit 220. The photoelectric conversion unit 210 has a configuration in which multiple photoelectric conversion elements (each photoelectric conversion element is called a cell) are arranged in a grid.

[0025] Figure 6 shows an example of the cell arrangement on the light-receiving surface of the photoelectric conversion unit 210, as viewed from the laser beam output side. Each square in Figure 6 represents a cell. Note that arranging multiple cells in a grid is just one example; a configuration in which multiple cells are arranged in a non-grid shape may also be adopted.

[0026] The switching control unit 220 changes (switches) the connection state of the cells in the photoelectric conversion unit 210 based on instructions (control signals) from the control device 300.

[0027] The functional unit (device) to which the power obtained by the photoelectric conversion unit 210 is supplied may be located inside the receiving device 200 or outside the receiving device 200.

[0028] Figure 7 shows an example of the configuration of the control device 300. As shown in Figure 7, the control device 300 includes a monitoring unit 310 and a control unit 320.

[0029] The monitoring unit 310 monitors the voltage of each cell in the photoelectric conversion unit 210. Based on the monitoring results from the monitoring unit 310, the control unit 320 controls the output of the laser in the transmitting device 100 or changes the connection status of the cells in the receiving device 200.

[0030] (Example of system operation) An example of operation of the optical wireless power transmission system having the above configuration will now be described. In this example, the light-emitting surface of the light source unit 110 and the light-receiving surface of the photoelectric conversion unit 210 are arranged facing each other. Furthermore, the arrangement of the lasers in the array laser, which is the light source unit 110, is the same as the arrangement of the cells in the photoelectric conversion unit 210.

[0031] For example, the arrangement of lasers in an array laser is as shown in Figure 6, which illustrates the cell arrangement. In Figure 6, which shows an array laser, each square indicates the location (position) where each laser is placed. Furthermore, the multiple cells (photoelectric conversion elements) that make up the photoelectric conversion unit 210 are electrically connected in series.

[0032] Figure 8 shows an image of the transmission of laser light from the light source unit 110 (array laser) to the photoelectric conversion unit 210. The light-emitting surface of the light source unit 110 (array laser) is shown, as is the light-receiving surface of the photoelectric conversion unit 210.

[0033] In Figure 8 (and Figures 11 and 12), for illustrative purposes, the intensity distribution (Gaussian distribution) on a plane perpendicular to the optical axis of the laser beam is shown with double circles (black and white). When the output is reduced, the intensity distribution is shown with only white circles.

[0034] As shown in Figure 8, the laser arrangement of the array laser is the same as the cell arrangement of the photoelectric conversion unit 210, both being in a 4x4 configuration. This arrangement ensures that the power of the light emitted from the laser to each cell is uniform. It is assumed that the size of the 4x4 arrangement of the light source unit 110 (array laser) and the 4x4 arrangement of the photoelectric conversion unit 210 are the same. In other words, for example, if both are shaped as shown in Figure 6, the overall size of the rectangle is the same for both the light source unit 110 (array laser) and the photoelectric conversion unit 210.

[0035] However, the assumption that the light source unit 110 (array-type laser) and the photoelectric conversion unit 210 are the same size is merely an example. The light source unit 110 (array-type laser) and the photoelectric conversion unit 210 may be of different sizes.

[0036] In this embodiment, the cells in the photoelectric conversion unit 210 are numbered in the order shown in Figure 9. In the photoelectric conversion unit 210, the cells are connected in series in this numbered order. Note that these numbers are the numbers when viewed from the transmitting device 100 side of the light-receiving surface of the photoelectric conversion unit 210.

[0037] The lasers in the light source unit 110 (array laser) corresponding to each cell in Figure 9 are as shown in Figure 10. The numbers shown in Figure 10 are the numbers when viewing the light-emitting surface of the light source unit 110 from the receiving device 200 side. The same numbers in Figure 9 and Figure 10 indicate the corresponding cells and lasers. For example, cell (1) in Figure 9 corresponds to laser (1) in Figure 10.

[0038] Furthermore, it is assumed that the light-emitting surface of the light source unit 110 (array-type laser) and the light-receiving surface of the photoelectric conversion unit 210 are parallel and their optical axes are aligned. Alignment of the optical axes means, for example, that a straight line extending perpendicularly from the center of the light-emitting surface coincides with a straight line extending perpendicularly from the center of the light-receiving surface. Note that even if the optical axes are misaligned by an error within a certain threshold, it may still be considered that the "optical axes are aligned." Also, even if the light-emitting surface of the light source unit 110 and the light-receiving surface of the photoelectric conversion unit 210 are misaligned by an error within a certain threshold, they may still be considered "parallel."

[0039] As mentioned above, "being parallel" and "having aligned optical axes" are just examples. The system may be configured in a way that does not require the conditions of "being parallel" or "having aligned optical axes."

[0040] In the configuration shown in Figure 8, laser light is output from each laser of the light source unit 110 toward the photoelectric conversion unit 210. At this time, the monitoring unit 310 of the control device 300 monitors the voltage of each cell in the photoelectric conversion unit 210.

[0041] Figure 11 shows an image of the light-receiving surface (image of the beam on the light-receiving surface) in the case of small atmospheric disturbances. As shown in Figure 11, when the disturbance is small, the disturbance of the beam output from each laser is small. Therefore, although each beam is offset from the center of the corresponding cell, it remains within the cell, and the light can be converted into electricity without wasting the transmitted power.

[0042] Figure 12 shows an image of the light-receiving surface in the case of large atmospheric disturbances. In situations of large disturbances, beam wandering causes the position where each beam reaches the light-receiving surface to shift from the center of the cell, as shown in Figure 12(a). As a result, there are cells where the beam does not fit (cells (2) and (11)). The voltage of such cells drops significantly.

[0043] When the control unit 320 of the control device 300 detects that there is a cell whose voltage has fallen below a reference value (or a cell whose voltage has fallen below a reference value), it disconnects that cell from the series connection. It also transmits this information (e.g., information indicating that cells (2) and (11) have been disconnected) to the transmitting device 100 and reduces the output (output power) of the laser corresponding to that cell. Figure 12(b) shows the image after the output has been reduced.

[0044] More specifically, "the control unit 320 disconnecting the cell from the series connection" means that the control unit 320 sends a control signal to the receiving device 200 instructing it to disconnect the cell from the series connection, and the switching control unit 220 of the receiving device 200 disconnects the corresponding cell in the photoelectric conversion unit 210 from the series connection based on the control signal.

[0045] Furthermore, "the control unit 320 lowering the laser output" means, more specifically, that the control unit 320 sends a control signal to the transmitting device 100 instructing it to lower the laser output, and that the light source control unit 110 of the transmitting device 100 lowers the output of the laser in the light source unit 110 based on the control signal.

[0046] By disconnecting cells whose voltage falls below a reference value from the series connection, the total current value of the photoelectric conversion unit 210 can be prevented from being limited by the current value of the cells with low power generation. This increases the total power generation of the photoelectric conversion unit 210, reduces energy loss, and suppresses heat generation in the photoelectric conversion unit 210.

[0047] The control device 300 reduces the output of the laser corresponding to a cell whose voltage falls below a reference value, and then monitors the cell voltage to monitor how the beam is being disturbed at minimum power. When the control device 300 detects that the beam has returned to the cell (i.e., when it detects that the voltage has exceeded a certain reference value), it reconnects the cell in series, restores the output of the corresponding laser, and allows the cell to contribute to power generation. This enables power generation with the optimal beam and cell connection in response to constantly changing disturbances.

[0048] In the example above, both "disconnecting the cells from the series connection" and "reducing the laser output" are performed when predetermined voltage conditions are met. However, it is also possible to choose not to perform either "disconnecting the cells from the series connection" or "reducing the laser output."

[0049] (Example of the configuration of the photoelectric conversion unit 210) Figure 13 shows an example of the circuit configuration of the photoelectric conversion unit 210. Each cell (each photoelectric conversion element) is indicated by a number from 1 to 16. The numbers 1 to 16 correspond to the numbers (1) to (16) in Figure 9.

[0050] Each cell is equipped with a voltmeter and a resistor. The voltmeter measures the voltage of the cell. The resistor is made sufficiently large to minimize current loss. Each cell is also equipped with a switch. The switch allows the cells to be connected in series or disconnected. The monitoring unit 310 of the control device 300 can monitor the voltage measured by the voltmeter for each cell. The control unit 320 can control the switches.

[0051] When each cell is sufficiently illuminated, all cells are connected in series, as shown in Figure 13. If the disturbance becomes large, for example, if the voltage value of cell 2 falls below the reference value, the switch on cell 2 will flip, as shown in Figure 14, and cell 2 will be disconnected from the series connection with the other cells. As shown in Figure 14, even when cell 2 is disconnected from the series connection, cells 1 and cells 3-16 remain connected in series.

[0052] At this time, although the output of the laser corresponding to cell 2 is reduced, the laser is still sending a beam, so power generation is still occurring in cell 2, and the voltage of cell 2 can continue to be monitored. When the voltage value of cell 2 exceeds a certain reference value (or becomes above the reference value), the connection is restored to its original state, as shown in Figure 13.

[0053] An example of the processing procedure of the control device 300 to achieve the above operation will be explained with reference to the flowchart in Figure 15. Note that Figure 5 shows a control flow focusing on a single cell in order to make the processing flow easier to understand. In reality, multiple cells are monitored simultaneously and control is performed.

[0054] The monitoring unit 310 continuously monitors the voltage of each cell (S101). In S102, the control unit 320 determines, based on the voltage values ​​of each cell obtained by the monitoring unit 310, whether there are any cells whose voltage value has fallen below the reference value A (determination 1).

[0055] When the control unit 320 detects that there is a cell whose voltage value has fallen below the reference value A (Decision 1: Yes), in S103, it disconnects that cell from the series connection. It also reduces the output intensity of the laser corresponding to that cell.

[0056] In S104, the control unit 320 determines whether the voltage value of the cell disconnected in S103 has become greater than the reference value B (determination 2).

[0057] If the control unit 320 detects that the voltage value of the cell in question is greater than the reference value B (Decision 2: Yes), in S105, it restores the cell to a series connection. It also returns the laser output to its normal output.

[0058] Note that reference value A and reference value B may be the same, reference value B may be smaller than reference value A, or reference value A may be smaller than reference value B. Furthermore, reference value A and reference value B may be different values ​​for each cell.

[0059] (Specific examples of how to switch a switch) The method for switching the switch is not limited to a specific method, but for example, there are Method 1 and Method 2 below. Both Method 1 and Method 2 are examples of methods for disconnecting photoelectric conversion elements that satisfy predetermined conditions regarding voltage from a series connection.

[0060] <Method 1: A method for extracting the maximum voltage> First, let's explain Method 1. As long as the voltage value being monitored in each cell does not fall below zero, a larger voltage can be obtained by connecting these cells in series.

[0061] Therefore, in Method 1, the control device 300 disconnects cells with a voltage value below 0 (or cells with a voltage value of 0 or less) from the series connection, while continuing to connect cells that have even a small amount of voltage (for example, cells with a voltage value greater than 0) in series.

[0062] The control device 300 monitors the voltage of a disconnected cell even after it has been disconnected from the series connection. When it detects that the voltage value exceeds a certain reference value, it reconnects the cell to the series connection. The reference value here is, for example, the voltage value obtained when the cell is exposed to sufficient light, and is determined based on the IV characteristics of the photoelectric conversion element.

[0063] Method 1 allows for the extraction of the largest possible voltage from the photoelectric conversion unit 210. Furthermore, by reducing the output of the laser sent to cells disconnected from the series connection, power waste can be eliminated.

[0064] <Method 2: Techniques to improve power generation efficiency> Next, we will explain Method 2. When the required voltage is determined for the power supply target, it is effective to control the cell connections in order to increase power generation efficiency while ensuring that voltage is secured.

[0065] In Method 2, the control device 300 arranges the multiple cells in the photoelectric conversion unit 210 in descending order of voltage, and adds up the voltage values ​​of the cells in descending order of voltage. Each time a voltage value is added, the control device 300 determines whether the summed value exceeds the required voltage. If it detects that the summed value exceeds the required voltage, it disconnects each cell in the arrangement that is after the cell on which the voltage was added from the series connection. It also reduces the output of the laser corresponding to each cell that has been disconnected from the series connection.

[0066] To simplify the explanation, let's assume that the voltages of cells 1 through 16 increase in this numerical order. That is, cell 1 has the highest voltage and cell 16 has the lowest voltage. The control device 300 repeatedly calculates by adding the voltage of cell 2 to the voltage of cell 1, and then adding the voltage of cell 3 to the result of that addition. If the sum of the voltages of cells 1 through 10 exceeds the required voltage, cells 11 through 16 are disconnected from the series connection.

[0067] Method 2 allows for increased power generation efficiency and reduced power loss by disconnecting low-voltage cells from the series connection while maintaining the required voltage.

[0068] (Example hardware configuration) The control device 300 described in this embodiment can be realized, for example, by having a computer execute a program. This computer may be a physical computer or a virtual machine on the cloud.

[0069] In other words, the control device 300 can be realized by using hardware resources such as the CPU and memory built into the computer to execute a program corresponding to the processing performed by the control device 300. The above program can be recorded on a computer-readable recording medium (such as portable memory), saved, and distributed. It is also possible to provide the above program via a network such as the Internet or email.

[0070] Figure 16 shows an example of the hardware configuration of the computer described above. The computer in Figure 16 has a drive device 1000, an auxiliary storage device 1002, a memory device 1003, a CPU 1004, an interface device 1005, a display device 1006, an input device 1007, an output device 1008, etc., all of which are interconnected by a bus BS. The computer may also be equipped with a GPU.

[0071] The program that enables processing on the computer is provided, for example, on a recording medium 1001 such as a CD-ROM or memory card. When the recording medium 1001 containing the program is set in the drive device 1000, the program is installed from the recording medium 1001 to the auxiliary storage device 1002 via the drive device 1000. However, the program does not necessarily have to be installed from the recording medium 1001; it may also be downloaded from another computer via a network. The auxiliary storage device 1002 stores the installed program as well as necessary files and data.

[0072] The memory device 1003 reads and stores a program from the auxiliary storage device 1002 when a program startup command is received. The CPU 1004 implements the functions related to the control device 300 according to the program stored in the memory device 1003. The interface device 1005 is used as an interface for connecting to a network, etc. The display device 1006 displays a GUI (Graphical User Interface) etc., generated by a program. The input device 1007 consists of a keyboard and mouse, buttons, or a touch panel, etc., and is used to input various operation commands. The output device 1008 outputs the calculation results.

[0073] (Summary of the embodiments, effects, etc.) As described above, in the optical wireless power transmission system according to this embodiment, by utilizing an array of lasers, light can be uniformly irradiated to each of the cells connected in series. Furthermore, cells that are strongly affected by disturbances and are not irradiated by the beam can be disconnected from the series connection to prevent them from contributing to power generation, and the output of the laser corresponding to those cells can be reduced, thereby ensuring power generation while reducing power generation losses.

[0074] In other words, the technology described in this embodiment makes it possible to efficiently extract power from light in optical wireless power transmission technology.

[0075] More specifically, the technology described in this embodiment allows for more uniform beam irradiation to each cell compared to conventional technology, enabling highly efficient conversion of light into electricity. Furthermore, by disconnecting cells that do not contribute to power generation or generate little power, and reducing the laser output, the energy converted into heat can be reduced, preventing deterioration of the characteristics of the photoelectric conversion element due to heat generation.

[0076] Furthermore, Method 1, which involves disconnecting the series connection of the cells, allows for obtaining the highest possible voltage and enables faster charging. Method 2 ensures the required voltage and allows for efficient power supply without wasting power.

[0077] The following additional information is disclosed regarding the embodiments described above.

[0078] <Note> (Additional note 1) A light source unit equipped with multiple light source elements, A photoelectric conversion unit comprising multiple photoelectric conversion elements, The light-emitting surface of the light source unit and the light-receiving surface of the photoelectric conversion unit are arranged opposite each other, and the arrangement of the plurality of photoelectric conversion elements on the light-receiving surface is the same as the arrangement of the plurality of light source elements on the light-emitting surface. Optical wireless power supply system. (Additional note 2) The plurality of photoelectric conversion elements are connected in series, Photoelectric conversion elements that meet predetermined voltage conditions are disconnected from the series connection. The optical wireless power supply system described in Appendix 1. (Additional note 3) The output intensity of the light source element corresponding to the photoelectric conversion element that has been disconnected from the series connection is reduced. The optical wireless power supply system described in Appendix 2. (Additional note 4) A receiving device usable in an optical wireless power transmission system, It has a photoelectric conversion unit equipped with multiple photoelectric conversion elements, When the receiving device is used in the optical wireless power supply system, the light-emitting surface of the light source unit, which has a plurality of light source elements, and the light-receiving surface of the photoelectric conversion unit are arranged opposite each other, and the arrangement of the plurality of photoelectric conversion elements on the light-receiving surface is the same as the arrangement of the plurality of light source elements on the light-emitting surface. Receiving device. (Additional note 5) A transmitting device usable in an optical wireless power transfer system, It has a light source unit equipped with multiple light source elements, When the transmitting device is used in the optical wireless power supply system, the light-emitting surface of the light source unit and the light-receiving surface of the photoelectric conversion unit, which is equipped with a plurality of photoelectric conversion elements, are arranged opposite each other, and the arrangement of the plurality of light source elements on the light-emitting surface is the same as the arrangement of the plurality of photoelectric conversion elements on the light-receiving surface. Transmitter. (Additional note 6) A control device for controlling an optical wireless power supply system comprising a light source unit having multiple light source elements and a photoelectric conversion unit having multiple photoelectric conversion elements connected in series, Memory and At least one processor connected to the memory, Includes, The aforementioned processor, The voltage of each photoelectric conversion element in the aforementioned photoelectric conversion unit is monitored, The photoelectric conversion elements that satisfy predetermined conditions for the voltage monitored by the monitoring unit are disconnected from the series connection. Control device. (Additional note 7) A control method executed by a control device that controls an optical wireless power supply system comprising a light source unit having multiple light source elements and a photoelectric conversion unit having multiple photoelectric conversion elements in series connection, A monitoring step involves monitoring the voltage of each photoelectric conversion element in the aforementioned photoelectric conversion unit, A control step which disconnects a photoelectric conversion element that satisfies predetermined conditions for the voltage monitored by the monitoring step from the series connection. A control method comprising the following features. (Additional note 8) A non-temporary storage medium storing a program for causing a computer to function as a component of the control device described in Appendix 6.

[0079] Although this embodiment has been described above, the present invention is not limited to this specific embodiment, and various modifications and changes are possible within the scope of the gist of the invention as described in the claims. [Explanation of symbols]

[0080] 100 Transmitter 110 Light source section 120 Light source control unit 200 Receiver 210 Photoelectric conversion unit 220 Switching Control Unit 300 Control device 310 Monitoring Department 320 Control Unit 1000 drive unit 1001 Recording media 1002 Auxiliary storage 1003 Memory device 1004 CPU 1005 Interface device 1006 Display device 1007 Input device 1008 Output device

Claims

1. A light source unit equipped with multiple light source elements, A photoelectric conversion unit comprising multiple photoelectric conversion elements, An optical wireless power supply system in which the light-emitting surface of the light source unit and the light-receiving surface of the photoelectric conversion unit are arranged opposite each other, and the arrangement of the plurality of photoelectric conversion elements on the light-receiving surface is the same as the arrangement of the plurality of light source elements on the light-emitting surface, The aforementioned multiple photoelectric conversion elements are connected in series, and any photoelectric conversion element that satisfies predetermined voltage conditions is disconnected from the series connection, and the output intensity of the light source element corresponding to the photoelectric conversion element disconnected from the series connection is reduced. Optical wireless power supply system.

2. A receiving device usable in an optical wireless power transmission system, It has a photoelectric conversion unit equipped with multiple photoelectric conversion elements, When the receiving device is used in the optical wireless power supply system, the light-emitting surface of the light source unit, which has a plurality of light source elements, and the light-receiving surface of the photoelectric conversion unit are arranged opposite each other, and the arrangement of the plurality of photoelectric conversion elements on the light-receiving surface is the same as the arrangement of the plurality of light source elements on the light-emitting surface. The aforementioned multiple photoelectric conversion elements are connected in series, and any photoelectric conversion element that satisfies predetermined voltage conditions is disconnected from the series connection, and the output intensity of the light source element corresponding to the photoelectric conversion element disconnected from the series connection is reduced. Receiving device.

3. A transmitting device usable in an optical wireless power transfer system, It has a light source unit equipped with multiple light source elements, When the transmitting device is used in the optical wireless power supply system, the light-emitting surface of the light source unit and the light-receiving surface of the photoelectric conversion unit, which is equipped with a plurality of photoelectric conversion elements, are arranged opposite each other, and the arrangement of the plurality of light source elements on the light-emitting surface is the same as the arrangement of the plurality of photoelectric conversion elements on the light-receiving surface. The aforementioned multiple photoelectric conversion elements are connected in series, and any photoelectric conversion element that satisfies predetermined voltage conditions is disconnected from the series connection, and the output intensity of the light source element corresponding to the photoelectric conversion element disconnected from the series connection is reduced. Transmitter.

4. A control device for controlling an optical wireless power supply system comprising a light source unit having multiple light source elements and a photoelectric conversion unit having multiple photoelectric conversion elements connected in series, A monitoring unit that monitors the voltage of each photoelectric conversion element in the aforementioned photoelectric conversion unit, A control unit disconnects a photoelectric conversion element that satisfies predetermined conditions for the voltage monitored by the monitoring unit from the series connection, and reduces the output intensity of the light source element corresponding to the photoelectric conversion element that has been disconnected from the series connection. A control device equipped with the following features.

5. A control method executed by a control device that controls an optical wireless power supply system comprising a light source unit having multiple light source elements and a photoelectric conversion unit having multiple photoelectric conversion elements in series connection, A monitoring step involves monitoring the voltage of each photoelectric conversion element in the aforementioned photoelectric conversion unit, A control step which involves disconnecting a photoelectric conversion element that satisfies predetermined conditions for the voltage monitored by the monitoring step from the series connection, and reducing the output intensity of the light source element corresponding to the photoelectric conversion element that has been disconnected from the series connection. A control method comprising the following features.

6. A program for causing a computer to function as a component of the control device described in claim 4.

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