Program, power supply method, power supply device, and optical power supply system

Abstract

To perform suitable power supply according to a load.SOLUTION: A program causes a computer capable of controlling a power supply device to execute: a function to cause the power supply device to transmit, to a power receiving device, trigger light for requesting load information related to a load of the power receiving device; and a function to, when the power supply device receives the load information from the power receiving device, control output of power supply light to be output to the power receiving device from the power supply device, on the basis of the load information.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a program, a power supply method, a power supply device, and an optical power supply system. [Background technology]

[0002] Recently, optical power supply systems have been studied in which electric power is converted into light (called power supply light) and transmitted, and the power supply light is converted into electrical energy for use as electric power. For example, Patent Document 1 discloses a technology for supplying only the power required by a load, thereby achieving effective energy utilization. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 1-89120 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to supply power in a suitable manner according to the load. [Means for solving the problem]

[0005] The program according to the present disclosure is A computer that can control the power supply device a function of causing the power supply device to transmit trigger light to the power receiving device, the trigger light requesting load information regarding a load of the power receiving device; a function of controlling, when the power supply device receives the load information from the power receiving device, an output of power supply light output from the power supply device to the power receiving device based on the load information; Execute the following. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to supply power in a suitable manner according to the load. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a configuration diagram of an optical power supply system according to an embodiment of the present disclosure. [Figure 2] 10 is a flowchart illustrating a flow of a power supply process according to an embodiment of the present disclosure. [Figure 3] 10 is a flowchart showing a first power supply control flow in the power supply process. [Figure 4] 10 is a flowchart showing a modified example of the first power supply control flow. [Figure 5] 10 is a flowchart showing a second power supply control flow in the power supply process. [Figure 6] 10 is a flowchart showing a third power supply control flow in the power supply process. [Figure 7] 10 is a flowchart showing a flow of a charging control flow in the power supply process. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings.

[0009] [Configuration of optical power supply system] 1, an optical power supply system 1 of this embodiment includes a power supply device (PSE: Power Sourcing Equipment) 110, an optical fiber cable 200, and a power receiving device (PD: Powered Device) 310. The optical power supply system 1 transmits power supply light 112 generated by the power supply device 110 to the power receiving device 310 via the optical fiber cable 200. In the present disclosure, the power supply device is a device that converts electric power into optical energy and supplies it, and the power receiving device is a device that receives optical energy and converts the optical energy into electricity (electric power). In addition, in the present disclosure, electric power and information (data) are transmitted between the power supply device and the power receiving device.

[0010] <Configuration of power supply device> The power supply device 110 includes a power supply semiconductor laser (power supply LD) 111, a communication photodiode (communication PD) 131, and a power supply control section 150. The power supply LD 111 oscillates with power from a power supply 121 and outputs power supply light (laser light) 112 . The communication PD 131 converts the signal light (laser light) 332 transmitted from the power receiving device 310 into an electric signal. This electric signal is demodulated by the demodulator 132, and information (upstream data) superimposed on the signal light 332 is extracted and transmitted to the power supply controller 150.

[0011] The power feeding control unit 150 is configured with, for example, a CPU (Central Processing Unit) and the like, and controls each unit of the power feeding device 110. For example, the power feeding control unit 150 controls the laser oscillation of the power feeding LD 111 based on the power from the power source 121 to generate the power feeding light 112, and controls the output of the power feeding light 112 based on the acquired upstream data, etc. This power feeding light 112 is output to the power receiving device 310 through the optical fiber cable 200. The power feeding control unit 150 may also include a storage unit that stores various types of information and programs. Furthermore, the power supply control unit 150 pulse-modulates the laser output of the power supply light 112, for example, to superimpose predetermined information on the power supply light 112. The information to be superimposed on the power supply light 112 is not particularly limited, and may be, for example, a signal that notifies the power receiving device 310 of the power transmission state of the power supply device 110, a signal that controls the device of the power receiving device 310 (or an external device), or a signal that requests information on the battery 330 or the external device 400, which will be described later.

[0012] <Configuration of optical fiber cable> The optical fiber cable 200 includes, for example, a single-core optical fiber that forms a transmission path for the power supply light 112 and the signal light 332. One end of the optical fiber cable 200 is connected to the power supply device 110, and the other end is connected to the power receiving device 310.

[0013] <Configuration of power receiving device> The power receiving device 310 includes a power supply photodiode (power supply PD) 320, a battery 330, a battery control unit (BMS) 331, a reflector 340, a modulator 341, a power load control unit 361, and a power receiving control unit 350.

[0014] The power supply PD 320 converts the power supply light 112 transmitted from the power supply device 110 through the optical fiber cable 200 into electric power. The converted electric power is supplied to the battery 330 or the external device 400 via the power receiving circuit 321. When data (downstream data) is superimposed on the power supply light 112, the data detection circuit 322 detects the data and transmits it to the power receiving control unit 350.

[0015] The battery 330 is a power storage device such as a lithium ion (Li-ion) battery. The battery 330 may also be a power storage device such as an electric double layer capacitor (EDLC). The battery 330 stores the power converted by the power supply PD 320 and supplies the stored power to each unit of the power receiving device 310 and the external device 400. The BMS 331 monitors and controls the charging and discharging of the battery 330. Specifically, the BMS 331 manages the temperature, current, voltage, state of charge (SOC), etc. of the battery 330. The BMS 331 also generates a control signal for the power supply based on the value of the state of charge (SOC), and can superimpose this signal on the optical signal 332 as upstream data by the modulator 341.

[0016] The reflector 340 reflects the leakage light 112 a of the power supply light 112 from the optical fiber cable 200 . The modulator 341 controls the reflector 340 based on information (upstream data) to be transmitted to the power supply device 110, superimposes the information on the return light resulting from reflection of the leaked light 112a, and outputs the superimposed information as the signal light 332. The output signal light 332 is transmitted to the power supply device 110 through the optical fiber cable 200. The information (upstream data) to be superimposed on the signal light 332 is not particularly limited, and may include, for example, information on required power, remaining charge of the battery 330, and information on an output abnormality of the power supply light 112. The configuration for generating the signal light 332 and transmitting it to the power supply device 110 is not limited to the above. For example, a light emitting unit such as a laser light source may be provided, and the signal light 332 may be generated by modulating the output light thereof.

[0017] The power load control unit 361 controls the power supplied from the battery 330 or the power supply PD 320 to the external device 400 based on, for example, a control command from the power receiving control unit 350. The external device 400 is connected to the power receiving device 310 as a power load, and is, for example, any of various devices. In this embodiment, the external device 400 is a power load of the power receiving device 310 (optical power supply system 1), but the power load may be, for example, a device within the power receiving device 310.

[0018] The power receiving control unit 350 is configured by, for example, a CPU (Central Processing Unit) and controls each unit of the power receiving device 310. For example, the power receiving control unit 350 controls the modulator 341 to generate the signal light 332, adjusts the power supplied to the external device 400 by the power load control unit 361, and controls each unit of the power receiving device 310 based on the downstream data. The power receiving control unit 350 may also include a storage unit that stores various types of information and programs.

[0019] Each of the power supply LD 111, communication PD 131, and power supply PD 320 is a photoelectric conversion element including a laser medium with a laser wavelength of 500 nm or less. More specifically, the semiconductor material constituting the semiconductor region that provides the optical-electrical conversion effect of each LD and PD is a semiconductor with a short laser wavelength of 500 nm or less. Semiconductors with short laser wavelengths have a large band gap and high photoelectric conversion efficiency, which improves the photoelectric conversion efficiency on the power generation side and power receiving side of optical power supply, thereby improving the optical power supply efficiency. For this purpose, the semiconductor material may be, for example, a semiconductor material of a laser medium with a laser wavelength (fundamental wave) of 200 to 500 nm, such as diamond, gallium oxide, aluminum nitride, or GaN. In addition, a semiconductor having a band gap of 2.4 eV or more is used as the semiconductor material. For example, semiconductor materials for the laser medium, such as diamond, gallium oxide, aluminum nitride, and GaN, having a band gap of 2.4 to 6.2 eV, may be used. Note that the longer the wavelength of laser light, the better the transmission efficiency, and the shorter the wavelength, the better the photoelectric conversion efficiency. Therefore, for long-distance transmission, a laser medium semiconductor material with a laser wavelength (fundamental wave) of greater than 500 nm may be used. Furthermore, if photoelectric conversion efficiency is prioritized, a laser medium semiconductor material with a laser wavelength (fundamental wave) of less than 200 nm may be used. These semiconductor materials can be applied to at least one of the LD and PD, improving the photoelectric conversion efficiency on the power supply side or power receiving side, and improving the power supply efficiency.

[0020] [Optical power supply system operation] Next, a power supply process for supplying power from the power supply device 110 to the power receiving device 310 in the optical power supply system 1 will be described. 2 to 7 are flowcharts showing the flow of the power supply process. The power supply process is executed by the power supply device 110 and the power receiving device 310 working together by deploying a program stored in each memory unit of the power supply device 110 and the power receiving device 310 based on, for example, a user operation on the power supply device 110. However, in the following description, the power supply control unit 150 of the power supply device 110 is the main control entity. The power supply device 110 and the power receiving device 310 appropriately perform necessary communication using downstream data superimposed on the power supply light 112 and upstream data superimposed on the signal light 332.

[0021] As shown in FIG. 2, when the power supply process is executed, first, the power supply control unit 150 of the power supply device 110 controls the laser oscillation of the power supply LD 111 to output the power supply light 112 (step S11). Here, power supply (power transmission) may be started in response to a request to start operation from the power receiving device 310 as a trigger, or periodically.

[0022] Then, the power supply light 112 is transmitted to the power receiving device 310 through the optical fiber cable 200, and each unit of the power receiving device 310 is started up (step S12). However, in this case, it is sufficient that at least the BMS 331 and the power load control unit 361 are activated by receiving power from the transmitted power supply light 112.

[0023] Next, the power supply control unit 150 determines whether load information regarding the load of the power receiving device 310 is known (step S13). In this specification, the term "load" refers to an "electric power load" unless otherwise specified. Specifically, here, the power supply control unit 150 determines whether the power consumption of the external device 400, which is the load of the power receiving device 310, is known, as the load information. Here, the load being "known" means, for example, that the power consumption of the load is pre-recorded in a storage unit of the power receiving device 310, or that the power supply device 110 can acquire the power consumption of the load based on a hardware information code of the external device 400, etc. In other words, the load being "known" means that the power consumption of the external device 400, which is the load, is set at the design stage of the power receiving device 310. More specifically, the power supply control unit 150 transmits trigger light from the power supply LD 111 to the power receiving device 310, requesting load information. If the power receiving device 310 holds the load information, the power supply control unit 150 receives the load information from the power receiving device 310 as upstream data.

[0024] In step S13, if it is determined that the load information is known (step S13; Yes), the power feeding control unit 150 determines whether the power fed by the power feeding light 112 has a margin for the load (step S14). Here, when the supplied power is greater than the power consumption of the external device 400, the power supply control unit 150 determines that the supplied power has a margin for the load. However, when step S14 is executed again after the first or second power supply control flow described below, the power supply power X is compared with the time average value Z2 of the power consumption, which is an actual measured value. If the operating state of the load changes, the magnitude relationship between the power supply power and the power consumption of the load may also change. In other words, there may be a transition between the first and second power supply control flows.

[0025] In step S14, when it is determined that the power supply has a margin for the load (step S14; Yes), the power supply control unit 150 executes the first power supply control flow (step S20).

[0026] <First power supply control flow> In the first power supply control flow, the output of the power supply light 112 is adjusted so that the battery 330 maintains a suitable charge rate (remaining power). As shown in FIG. 3, when the first power supply control flow is executed, first, the power supply control unit 150 measures the state of charge (SOC) of the battery 330 using the BMS 331 (step S21).

[0027] Next, the power supply control unit 150 determines whether or not there is a necessary storage margin based on the SOC of the battery 330 acquired in step S21 (step S22). Here, the power storage margin of the battery 330, which serves as a buffer for load fluctuations, is determined based on the SOC. Specifically, when the SOC is a value (for example, 50% or less) that may cause the power supply from the battery 330 to be unable to follow the load fluctuations, the power supply control unit 150 determines that there is not enough power storage margin.

[0028] In step S22, if it is determined that there is no power storage margin (step S22; No), the power supply control unit 150 executes a charging control flow described later to charge the battery 330 (step S50), and proceeds to the process of step S21 described above.

[0029] In step S22, if it is determined that there is a power storage surplus (step S22; Yes), the power supply control unit 150 starts power supply from the battery 330 to the external device 400 which is a load (step S23).

[0030] Next, the power supply control unit 150 measures the power consumption of the external device 400 which is a load (step S24). Here, the power supply control unit 150 measures the power consumption Z of the external device 400 at each specified time, and then calculates the time average value Z2 thereof. The power supply control unit 150 sets this value as the determination threshold value in steps S14 and the like in subsequent times.

[0031] Next, the power supply control unit 150 determines whether the power supply power is greater than the power consumption of the load (step S25). Here, the power supply control unit 150 compares the power supply power X with the time average value Z2 of the power consumption of the external device 400.

[0032] And when the power supply power X is greater than the time average value Z2 of the power consumption (X≧Z2: step S25; Yes), the power supply control unit 150 reduces the output of the power supply light 112 by a predetermined value (step S26). At this time, the power reception control unit 350 superimposes the information of the required power on the signal light 332 and transmits it to the power supply device 110. The power supply control unit 150 of the power supply device 110 adjusts the output of the power supply LD111 based on the received information of the required power. On the other hand, when the power supply power X is smaller than the time average value Z2 of the power consumption (X<Z2: step S25; No), the power supply control unit 150 increases the output of the power supply light 112 by a predetermined value (step S27).

[0033] Next, the power supply control unit 150 determines whether there is an operation stop instruction for the external device 400 from the power supply device 110 (or the host of the power reception device 310) (step S28). And when there is no operation stop instruction for the external device 400 (step S28; No), the power supply control unit 150 transfers the process to step S24 described above. Therefore, the processes of steps S24 to S28 are repeated until an instruction to stop operation of the external device 400 is received. As a result, if the supplied power is insufficient for the power consumption of the load, the output of the power supply light 112 is increased, and if it is too much, the output of the power supply light 112 is decreased. In other words, the output of the power supply light 112 is adjusted so that the battery 330 maintains an appropriate charging rate. Generally, secondary batteries such as lithium-ion batteries are prone to deterioration when their internal voltage is high, so it is sometimes best not to fully charge them.

[0034] In step S28, if an instruction to stop the operation of the external device 400 has been issued (step S28; Yes), the power supply control unit 150 charges the battery 330 to a predetermined value (for example, 70%) (step S29). Here, the battery 330 is charged to an amount that is somewhat greater than the threshold value of the power storage margin (for example, 50%) for the next operation. This completes the first power supply control flow.

[0035] <Modification of the first power supply control flow> In the first power supply control flow described above, the output of the power supply light 112 is adjusted to maintain the charging rate of the battery 330, but a power supply stop period may be provided to maintain the SOC within a certain range. In this case, as shown in FIG. 4, first, the power supply control unit 150 measures the state of charge (SOC) of the battery 330 (step S21a), similarly to step S21 of the first power supply control flow described above.

[0036] Next, the power supply control unit 150 determines whether or not the SOC of the battery 330 acquired in step S21a is greater than a predetermined first threshold value Th1 (for example, 60%) (step S22a). Here, the discharge margin of the battery 330, which serves as a buffer for load fluctuations, is determined based on the SOC.

[0037] In step S22a, when it is determined that the SOC is smaller than the first threshold Th1 (SOC < Th1: step S22a; No), the power supply control unit 150 executes the charging control flow described below to charge the battery 330 (step S50), and transfers the process to the above-described step S21a.

[0038] In step S22a, when it is determined that the SOC is larger than the first threshold Th1 (SOC ≥ Th1: step S22a; Yes), the power supply control unit 150 stops the power supply from the power supply device 110 (step S23a). Then, only the battery 330 drives (supplies power to) the external device 400.

[0039] Next, after a lapse of a predetermined time, the power supply control unit 150 starts the power supply from the power supply device 110 again (step S24a). Then, the power supply control unit 150 measures the SOC of the battery 330. This process is for the purpose of polling by which the power supply control unit 150 periodically monitors the SOC of the battery 330. Therefore, when the execution entity is the power reception control unit 350, this process simply becomes "SOC measurement" or "instructing the polling interval to the power supply control unit 150".

[0040] Next, the power supply control unit 150 determines whether the SOC of the battery 330 is larger than a predetermined second threshold Th2 (for example, 40%) that is smaller than the first threshold Th1 (step S25a).

[0041] When the SOC of the battery 330 is smaller than the second threshold Th2 (SOC < Th2: step S25a; No), the power supply control unit 150 charges the battery 330 until the SOC becomes the first threshold Th1 (step S26a), and transfers the process to the above-described step S24a.

[0042] On the other hand, when the SOC of the battery 330 is larger than the second threshold Th2 (SOC ≥ Th2: step S25a; Yes), the power supply control unit 150 determines whether there is an instruction to stop the operation of the external device 400 from the power supply device 110 (or the host of the power reception device 310) (step S28a). If there is no instruction to stop the operation of the external device 400 (step S28a; No), the power supply control unit 150 proceeds to the process of step S23a described above. Therefore, the processes of steps S23a to S28a are repeated until an instruction to stop operation of the external device 400 is received. As a result, it is determined whether the battery 330 has been discharged to an SOC of the second threshold value Th2, and if there is no room for discharge, the battery 330 is charged to the first threshold value Th1. That is, the power supply light 112 is stopped and intermittently output so that the SOC is maintained between the first threshold value Th1 and the second threshold value Th2.

[0043] In step S28a, if an instruction to stop the operation of the external device 400 has been issued (step S28a; Yes), the power supply control unit 150 charges the battery 330 to a predetermined value (for example, 80%) (step S29a). Here, the battery 330 is charged to a level somewhat higher than the first threshold value Th1 (for example, 60%) for the next operation. This completes the modified example of the first power supply control flow.

[0044] As shown in FIG. 2, if it is determined in step S14 above that the feed power is insufficient for the load (step S14; No), the power feed control unit 150 executes the second power feed control flow (step S30).

[0045] <Second power supply control flow> In the second power supply control flow, the power supply light 112 supplies power to the external device 400 at a predetermined output value (for example, the maximum output value), and the battery 330 makes up for the shortage. As shown in FIG. 5, when the second power supply control flow is executed, first, the power supply control unit 150 measures the state of charge (SOC) of the battery 330 (step S31), similarly to step S21 of the first power supply control flow described above.

[0046] Next, the power supply control unit 150 determines whether or not there is a necessary storage margin based on the SOC of the battery 330 acquired in step S31 (step S32). Here, if the SOC of the battery 330 is lower than a predetermined amount (for example, 70%), it is determined that there is no room for storing power. This determination threshold is set depending on the type of external device 400. For example, in the case of an external device 400 that requires a large amount of power for only several tens of seconds, such as a backup monitor, the determination threshold is set so as to provide an operating time several times longer than the expected usage time.

[0047] In step S32, if it is determined that there is no power storage margin (step S32; No), the power supply control unit 150 executes a charging control flow described later to charge the battery 330 (step S50), and proceeds to the process of step S31 described above.

[0048] In step S32, if it is determined that there is a power storage margin (step S32; Yes), the power supply control unit 150 starts supplying power from the battery 330 to the external device 400, which is a load (step S33).

[0049] Next, the power supply control unit 150 measures the power consumption of the external device 400, which is a load (step S34). Here, the power supply control section 150 measures the power consumption Z of the external device 400 for each specified time period and calculates the time average value Z2.

[0050] Next, the power supply control unit 150 measures the state of charge (SOC) of the battery 330 in the same manner as in step S31 described above (step S35).

[0051] Next, the power supply control unit 150 calculates the remaining time for which the external device 400 can be used based on the SOC of the battery 330 and the power consumption Z2 of the external device 400 (step S36). Then, the power supply control unit 150 notifies the system or the user of the calculated usable time of the external device 400 as necessary (step S37). The manner of notification is not particularly limited.

[0052] Next, the power supply control unit 150 determines whether or not there is an instruction to stop the operation of the external device 400 from the power supply device 110 (or the host of the power receiving device 310) (step S38). If there is no instruction to stop the operation of the external device 400 (step S38; No), the power supply control unit 150 proceeds to the process of step S34 described above. Therefore, the processes of steps S34 to S38 are repeated until an instruction to stop the operation of the external device 400 is received. During this time, even if the power supply light 112 is at a predetermined output (for example, maximum output) and power is further supplied from the battery 330, the battery 330 is consumed. In other words, while the power supply light 112 supplies power to the external device 400, the battery 330 makes up for the shortage.

[0053] In step S38, if an instruction to stop the operation of the external device 400 has been issued (step S38; Yes), the power supply control section 150 executes a charging control flow described later to charge the battery 330 (step S50). Here, for example, the battery 330 is fully charged in preparation for the next operation. This completes the second power supply control flow.

[0054] As shown in FIG. 2, when it is determined in the above-mentioned step S13 that the load information is not known (step S13; No), the power supply control unit 150 executes a third power supply control flow (step S40).

[0055] <Third power supply control flow> In the third power supply control flow, when information about the load of the external device 400 is unknown, the information about this load is acquired. As shown in FIG. 6, when the third power supply control flow is executed, first, the power supply control unit 150 measures the state of charge (SOC) of the battery 330 (step S41), similarly to step S21 of the first power supply control flow described above.

[0056] Next, the power supply control unit 150 determines whether or not there is a necessary storage margin based on the SOC of the battery 330 acquired in step S41 (step S42). Here, if the SOC of the battery 330 is smaller than a predetermined amount (for example, 60%), it is determined that there is no room for storing electricity.

[0057] In step S42, if it is determined that there is no power storage margin (step S42; No), the power supply control unit 150 executes a charging control flow described later to charge the battery 330 (step S50), and proceeds to the process of step S41 described above.

[0058] In step S42, if it is determined that there is a power storage margin (step S42; Yes), the power supply control unit 150 starts supplying power from the battery 330 to the external device 400, which is a load (step S43).

[0059] Next, the power supply control unit 150 determines whether the amount of power supply is sufficient for the power consumption of the external device 400 (step S44). Here, for example, based on the power supply power X, the discharge power (actual value) Y1 of the battery 330, and the power consumption Z of the external device 400, if (X+Y1)>Z, it is determined that there is no shortage of power supply. If it is determined that the amount of power supply is insufficient (step S44; No), the power supply control unit 150 proceeds to step S48, which will be described later.

[0060] In step S44, if it is determined that the amount of power supply is sufficient (step S44; Yes), the power supply control unit 150 measures the power consumption of the external device 400 (step S45). Here, the power supply control section 150 measures the power consumption Z of the external device 400 for each specified time period and calculates the time average value Z2.

[0061] Next, the power supply control unit 150 determines whether the supplied power is greater than the power consumption of the load (step S46). Here, the power supply control section 150 compares the supply power X with the time average value Z2 of the power consumption of the external device 400.

[0062] In step S46, if the feed power X is greater than the time average value Z2 of the power consumption (X>Z2: step S46; Yes), the power feeding control unit 150 proceeds to step S24, S21a or S24a of the first power feeding control flow described above.

[0063] Furthermore, in step S46, if the supply power X is not greater than the time average value Z2 of the power consumption (X≦Z2: step S46; No), the power supply control unit 150 determines whether the amount of power supply is sufficient for the power consumption of the external device 400 in light of the specification value (step S47). Here, for example, based on the power supply power X, the maximum discharge power (spec value) Y2 of the battery 330, and the power consumption Z of the external device 400, if (X+Y2)>Z, it is determined that there is no shortage of power supply. The power consumption Z may be multiplied by a safety factor (e.g., 80%). Generally, the dischargeable current of a battery is specified based on the component specifications of the protection circuit, etc.

[0064] In step S47, when it is determined that the amount of power supply is not insufficient in light of the specification value (step S47; Yes), the power supply control unit 150 proceeds to the process of step S34 of the second power supply control flow described above.

[0065] Furthermore, in step S47, if it is determined that the amount of power supply is insufficient in light of the specification value (step S47; No), power supply control section 150 stops power supply from power supply device 110 (step S48). Then, the power supply control unit 150 notifies the system and the user that the external device 400 cannot be driven appropriately due to a power shortage (step S49). The manner of notification is not particularly limited.

[0066] Next, the power supply control unit 150 executes a charging control flow described later to charge the battery 330 (step S50). This completes the third power supply control flow.

[0067] As shown in FIG. 2, when the first power supply control flow, the second power supply control flow, or the third power supply control flow is completed, the power supply control unit 150 determines whether to terminate the power supply process (step S19), and if it determines not to terminate it (step S19; No), the process proceeds to the above-mentioned step S14. On the other hand, if it is determined that the power supply process should be ended (step S19; Yes), the power supply control unit 150 ends the power supply process.

[0068] <Charging control flow> Next, a charging control flow executed during the power supply process will be described. The charging control flow is executed when the battery 330 is charged. As shown in FIG. 7, when the charging control flow is executed, first, the power supply control unit 150 controls the laser oscillation of the power supply LD 111 to output the power supply light 112, similar to step S11 described above (step S51). Next, the power transmission control unit 150 activates the BMS 331 and measures the state of charge (SOC) of the battery 330 (step S52). At this time, the power reception control unit 350 does not need to be activated.

[0069] Next, the power supply control unit 150 determines whether or not to charge the battery 330 based on the SOC measured in step S51 (step S53). Here, the power supply control unit 150 determines to perform charging when the charge level is less than a predetermined value (for example, 95%) that is close to full charge. If it is determined that charging is not to be performed (step S53; No), the power supply control unit 150 proceeds to step S61, which will be described later.

[0070] In step S53, if it is determined that the battery 330 is to be charged (step S53; Yes), the power supply control unit 150 starts charging the battery 330, and measures the charging current of the battery 330 using the BMS 331 (step S54).

[0071] Next, the power supply control unit 150 determines whether the power supply is sufficient based on the charging current (step S55). Here, the power supply control unit 150 determines that the supplied power is insufficient when the maximum current value (spec value) of the battery 330 is greater than the charging current measured in step S54. If it is determined that the power supply is insufficient (step S55; No), the power supply control unit 150 increases the output of the power supply light 112 by a predetermined value (step S56) and proceeds to the above-mentioned step S54. This process assumes a power supply shortage in CC charging, which charges at a constant current.

[0072] In step S55, when it is determined that the supplied power is sufficient (step S55; Yes), the power supply control unit 150 measures the charging current of the battery 330 using the BMS 331 (step S57).

[0073] Next, the power supply control unit 150 determines whether the fluctuation (decrease) in the charging current is greater than a predetermined threshold (step S58). This determination is a determination of whether the received power is excessive in CV charging, which is charging at a constant voltage. If it is determined that the decrease in the charging current is smaller than the threshold value (step S58; No), the process proceeds to step S57 described above.

[0074] Furthermore, in step S58, if it is determined that the decrease in the charging current is greater than the threshold value (step S58; Yes), the power feeding control unit 150 decreases the feeding power by a predetermined value (step S59).

[0075] Next, the power supply control unit 150 determines whether the battery 330 is fully charged (step S60), and if it determines that the battery 330 is not fully charged (step S60; No), the process proceeds to step S57 described above. Here, the power supply control unit 150 determines that the battery 330 is fully charged when the charging current is equal to or less than a preset charging termination threshold value for processing.

[0076] If it is determined in step S60 that the battery 330 is fully charged, the power supply control unit 150 transmits a power supply stop instruction to the power supply device 110 to stop power supply (step S61).

[0077] Next, the power supply control unit 150 determines whether or not to end the charging control flow (step S62), and if it determines not to end the charging control flow (step S62; No), the process proceeds to the above-mentioned step S51. On the other hand, if it is determined that the charging control flow should be ended (step S62; Yes), the power supply control unit 150 ends the charging control flow.

[0078] [Technical effect of this embodiment] As described above, according to the present embodiment, a trigger light requesting load information related to the load (external device 400) of the power receiving device 310 is transmitted to the power receiving device 310. Then, when the load information is received from the power receiving device 310, the output of the power supply light 112 output from the power supply device 110 to the power receiving device 310 is controlled based on the load information. This allows for obtaining load information and supplying power appropriately according to the load. As a result, by optimizing laser oscillation, it is possible to reduce unnecessary power consumption and deterioration of the optical device.

[0079] Furthermore, according to this embodiment, when it is determined that the load information is known, the output of the power supply light 112 is controlled based on the load information. Therefore, for example, by storing load information in advance in a storage unit, the output of the power supply light 112 can be controlled based on the load information.

[0080] Furthermore, according to this embodiment, the output of the power supply light 112 is controlled based on the power supplied by the power supply light 112 and the power consumption of the load. This allows the output of the power supply light 112 to be suitably adjusted according to the balance between the supply power and the power consumption of the load. For example, if the power receiving device 310 has a battery 330, the power supply light 112 can be output so that the charging rate of the battery 330 is maintained within a predetermined range.

[0081] Furthermore, according to this embodiment, power is supplied to the load from the power supply light 112 and the battery 330, and the power supply light 112 is controlled to be turned on or off based on the state of charge (SOC) of the battery 330. This allows the power supply light 112 to be stopped intermittently so that the SOC is maintained within a certain range, thereby preventing unnecessary power consumption and deterioration of the optical device due to continuous use of the power supply LD 111.

[0082] Furthermore, according to this embodiment, power is supplied to the load from the power supply light 112 and the battery 330, and the remaining time during which power can be supplied to the load is calculated based on the state of charge (SOC) of the battery 330 and the power consumption of the load. This allows the remaining time for which the external device 400 can be used to be known in the case of a power supply mode in which the power supply light 112 of a predetermined output (for example, maximum output) is used to supply power to the external device 400 and the shortage is supplemented by the battery 330.

[0083] Furthermore, according to this embodiment, when it is determined that the load information is not known, power is supplied to the load and the power consumption of the load is measured. This allows the power consumption of the load to be obtained by actual measurement even if the load information is initially unknown.

[0084] Furthermore, according to this embodiment, the power supply control unit 150 of the power supply device 110 causes the battery control unit (BMS) 331 to charge the battery 330. That is, the battery 330 can be charged without starting the power reception control unit 350 of the power receiving device 310. When considering the actual operation of optical power transmission via optical fiber, since the power supply is still not very large, it is expected that the power will be stored in a power storage device such as a lithium-ion battery and then used in a downstream circuit. This configuration is also useful as a countermeasure against load fluctuations in the downstream circuit. For example, for devices that operate intermittently, such as a car's backup camera or a remote sensor, one possible usage scenario is to charge the battery when it is not in operation and discharge the battery when it is in operation. In this case, if the charge level of the power storage device is low, even the control unit on the power receiving side may not be able to operate, and the battery may not be able to be charged. In this regard, in this embodiment, the battery 330 can be suitably charged without the need to start the power reception control unit 350.

[0085] [others] The above describes the embodiments of the present disclosure. However, the content of the present disclosure is not limited to the above embodiments. The details shown in the embodiments can be modified as appropriate without departing from the spirit of the invention.

[0086] For example, in the above embodiment, the power supply device 110 and the power receiving device 310 communicate with each other using downstream data superimposed on the power supply light 112 and upstream data superimposed on the signal light 332. However, the communication mode between the power supply device 110 and the power receiving device 310 is not particularly limited. For example, radio wave communication may be used instead of optical communication. Furthermore, the light emitting unit for signals including the trigger light may be different from the light emitting unit that outputs the power supply light.

[0087] Furthermore, the executing entity (controlling entity) of each process in the power supply process is not limited to those described above. In the above embodiment, for the sake of simplicity, the main controlling entity in the power supply process has been described as the power supply control unit 150 of the power supply device 110, but each process may be executed by the power receiving control unit 350 or each component.

[0088] In the above embodiment, a semiconductor laser is used as an example of the light source of the power supply light emitted by the power supply device, but the present invention is not limited to this. The light source of the power supply light emitted by the power supply device may be other light sources such as an LED (Light Emitting Diode) in addition to a laser light source.

[0089] Although the above embodiment has been described as an example of a power receiving device to which power supply light is transmitted from a power supply device through an optical fiber cable, the present invention can be widely applied to power receiving devices to which power supply light is transmitted.

[0090] Additionally, the functions performed by the components described herein may be implemented in circuitry or processing circuitry, including general-purpose processors, application-specific processors, integrated circuits, ASICs (Application Specific Integrated Circuits), CPUs (Central Processing Units), conventional circuits, and / or combinations thereof, programmed to perform the described functions. Processors include transistors and other circuits and are considered circuitry or processing circuitry. A processor may also be a programmed processor that executes a program stored in memory. In this specification, a circuit, unit, or means is hardware that is programmed to perform or executes the described functions. The hardware may be any hardware disclosed herein or any hardware known to be programmed to perform or execute the described functions. When the hardware is a processor, which is considered a type of circuitry, the circuit, means, or unit is a combination of hardware and software used to configure the hardware and / or processor.

[0091] An embodiment of the present disclosure will be described below. (1) The program is A computer that can control the power supply device a function of causing the power supply device to transmit trigger light to the power receiving device, the trigger light requesting load information regarding a load of the power receiving device; a function of controlling, when the power supply device receives the load information from the power receiving device, an output of power supply light output from the power supply device to the power receiving device based on the load information; Execute the following.

[0092] (2) In the program (1) above, The control function is determining whether the load information is known; When it is determined that the load information is known, the output of the power supply light is controlled based on the load information.

[0093] (3) In the program (1) or (2) above, The control function controls the output of the power supply light based on the power supplied by the power supply light and the power consumption of the load.

[0094] (4) In any of the above programs (1) to (3), the power receiving device includes a battery; The control function is supplying power from the powered light and the battery to the load; The switching between outputting and stopping the power supply light is controlled based on the charging rate of the battery.

[0095] (5) In any of the above programs (1) to (4), the power receiving device includes a battery; The control function is supplying power from the power supply light and the battery to the load; The remaining time during which power can be supplied to the load is calculated based on the charging rate of the battery and the power consumption of the load.

[0096] (6) In any of the above programs (1) to (5), The control function is determining whether the load information is known; If it is determined that the load information is not known, power is supplied to the load and the power consumption of the load is measured.

[0097] (7) In any of the above programs (1) to (6), the power receiving device includes a battery and a battery control unit that manages the battery; The control function is arranged in the power supply device, and causes the battery control unit to charge the battery.

[0098] (8) In any of the above programs (1) to (7), the power receiving device includes a battery; The output of the power supply light is controlled based on fluctuations in the charging current that charges the battery.

[0099] (9) The power supply method is A control unit capable of controlling the power supply device a transmitting step of transmitting trigger light from the power supply device to the power receiving device, the trigger light requesting load information regarding a load of the power receiving device; a control step of controlling, when the power supply device receives the load information from the power receiving device, an output of power supply light output from the power supply device to the power receiving device based on the load information; Execute.

[0100] (10) The power supply device is a light emitting unit configured to transmit trigger light to the power receiving device to request load information regarding the load of the power receiving device; a control unit that, upon receiving the load information from the power receiving device, controls an output of power supply light to be output to the power receiving device based on the load information; Equipped with.

[0101] (11) The optical power supply system is The above 10 power supply devices, the power receiving device; an optical fiber cable that transmits the power supply light between the power supply device and the power receiving device; Equipped with. [Explanation of symbols]

[0102] 1 Optical power supply system 110 Power supply equipment 111 Power supply semiconductor laser (light emitting part) 112 Power supply light 131 Communication photodiode (receiving part) 150 Power supply control unit (control unit) 200 Fiber Optic Cable 310 Power receiving device 320 Power supply photodiode 330 Battery 331 Battery Management System (BMS) 332 Signal Light 350 Power receiving control unit 400 External equipment (load) Th1 First threshold Th2 Second threshold X Power Supply Y1 Discharge power (actual value) Y2 Discharge power (spec value) Z power consumption Z2 Average value of power consumption over time

Claims

1. A computer that can control the power supply device a function of causing the power supply device to transmit trigger light to the power receiving device, the trigger light requesting load information regarding a load of the power receiving device; a function of controlling, when the power supply device receives the load information from the power receiving device, an output of power supply light output from the power supply device to the power receiving device based on the load information; A program that executes the following.

2. The control function is determining whether the load information is known; When it is determined that the load information is known, the output of the power supply light is controlled based on the load information. The program according to claim 1.

3. the control function controls the output of the power supply light based on the power supply power by the power supply light and the power consumption of the load; The program according to claim 1.

4. the power receiving device includes a battery; The control function is supplying power from the powered light and the battery to the load; and controlling switching between outputting and stopping the power supply light based on the charging rate of the battery. The program according to claim 1.

5. the power receiving device includes a battery; The control function is supplying power to the load from the powered light and the battery; calculating a remaining time during which power can be supplied to the load based on the charging rate of the battery and the power consumption of the load; The program according to claim 1.

6. The control function is determining whether the load information is known; If it is determined that the load information is not known, power is supplied to the load and the power consumption of the load is measured. The program according to claim 1.

7. the power receiving device includes a battery and a battery control unit that manages the battery; the control function is disposed in the power supply device, and causes the battery control unit to charge the battery; The program according to claim 1.

8. the power receiving device includes a battery; controlling the output of the power supply light based on fluctuations in a charging current for charging the battery; The program according to claim 1.

9. A control unit capable of controlling the power supply device a transmitting step of transmitting trigger light from the power supply device to the power receiving device, the trigger light requesting load information regarding a load of the power receiving device; a control step of controlling, when the power supply device receives the load information from the power receiving device, an output of power supply light output from the power supply device to the power receiving device based on the load information; A power supply method that performs the above.

10. a light emitting unit configured to transmit trigger light to the power receiving device to request load information regarding the load of the power receiving device; a control unit that, upon receiving the load information from the power receiving device, controls an output of power supply light to be output to the power receiving device based on the load information; A power supply device comprising:

11. The power supply device according to claim 10; the power receiving device; an optical fiber cable that transmits the power supply light between the power supply device and the power receiving device; An optical power supply system comprising:

Images