Solar charging system

Abstract

To provide a solar charging system that can achieve a cost reduction and downsizing by reducing a total number of components used for power generation control of a plurality of solar panels.SOLUTION: In a solar charging system including a plurality of solar modules that generate electric power using sunlight, at least one master solar module of the plurality of solar modules comprises: a master solar panel; a sensor for acquiring an electric power generation state of the master solar panel; an instruction unit that instructs power generation control of the master solar panel based on the electric power generation state acquired by the sensor; and a master power generation controlling unit that controls the electric power generation of the master solar panel according to an instruction from the instruction uni. A slave solar module other than the master solar module among the plurality of solar modules comprises: a slave solar panel; and a slave power generation controlling unit that controls the electric power generation of the slave solar panel using the instruction from the instruction unit of the master solar module, respectively.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a solar charging system mounted on a vehicle or the like. [Background technology]

[0002] Patent Document 1 discloses an in-vehicle solar charging system equipped with multiple solar panels. In the solar charging system described in Patent Document 1, each solar control device provided for each solar panel executes maximum power point tracking (MPPT) control for the solar panel that is the control target of the device. In this MPPT control, in order to search for the maximum power point with high accuracy when the output voltage of the solar panel changes due to environmental changes such as changes in solar radiation conditions, a scan process is performed to scan the output voltage of the solar panel and find the optimal point on the PV curve. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-141545 A Summary of the Invention [Problem to be solved by the invention]

[0004] The solar charging system described in Patent Document 1 has a configuration in which multiple solar control devices control each solar panel. In such a configuration, each solar panel requires components such as a sensor that acquires the power generation state of the solar panel and a configuration for performing a scan process. For this reason, a solar charging system including multiple solar panels as disclosed in Patent Document 1 has problems such as increased system costs and an increased system scale (number of elements).

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a solar charging system that can reduce the number of components used to control the power generation of solar panels in a system that includes multiple solar panels, thereby reducing the cost and scale of the system. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the disclosed technology is a solar charging system including multiple solar modules that generate power using sunlight, wherein at least one master solar module among the multiple solar modules comprises a master solar panel, a sensor that acquires the power generation state of the master solar panel, an instruction unit that instructs power generation control of the master solar panel based on the power generation state acquired by the sensor, and a master power generation control unit that controls power generation of the master solar panel in accordance with instructions from the instruction unit, and each slave solar module among the multiple solar modules other than the master solar module comprises a slave solar panel, and a slave power generation control unit that controls power generation of the slave solar panel using instructions from the instruction unit of the master solar module. Effect of the Invention

[0007] According to the present disclosure, in a solar charging system including multiple solar panels, the number of components such as sensors used for power generation control of the solar panels can be reduced, thereby reducing the cost and scale of the solar charging system. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing a schematic configuration example of a solar charging system according to an embodiment of the present disclosure. [Figure 2A] A diagram showing an example of multiple solar panels mounted on a vehicle in a multi-system structure. [Figure 2B] A diagram showing an example of multiple solar panels mounted on a vehicle in a multi-junction structure. [Diagram 3] FIG. 2 is a block diagram showing another schematic configuration example of the solar charging system according to the embodiment; [Figure 4] Flowchart of scanning process control performed by the solar charging system DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In the solar charging system including multiple solar panels of the present disclosure, the power generation control instruction for a specific solar panel is also used for the power generation control of other solar panels that have a correlation with the specific solar panel in terms of solar radiation conditions. By sharing the power generation control instruction among several solar panels in this way, it is possible to reduce some of the components such as sensors that were previously installed for each solar panel. Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings.

[0010] <Embodiment> [composition] Fig. 1 is a block diagram showing a schematic configuration of a solar charging system 1 according to an embodiment of the present disclosure. The solar charging system 1 illustrated in Fig. 1 includes a master solar module 10, a plurality of slave solar modules 20 and 30, a battery 50, and a load device 60. In Fig. 1, connection lines through which power is transmitted are indicated by thick solid lines, and connection lines through which control signals and detection values ​​other than power are transmitted and received are indicated by thin solid lines. This solar charging system 1 can be mounted on vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs).

[0011] The master solar module 10, the slave solar module 20, and the slave solar module 30 are each a power generation device that generates power by receiving irradiation of sunlight. The master solar module 10 is the main solar module that controls the operation of all the solar modules, and the slave solar module 20 and the slave solar module 30 are subordinate solar modules whose operation is controlled by the master solar module 10. The power generated by the master solar module 10, the slave solar module 20, and the slave solar module 30 is output to a battery 50, a load device 60, and the like that are connected to these solar modules.

[0012] The master solar module 10 includes a master solar panel 101, a master power generation control unit 102, a sensor 103, and an instruction unit 104.

[0013] The master solar panel 101 is a device capable of generating power according to the amount of sunlight it is exposed to, and is typically a collection of solar battery cells.

[0014] The master power generation control unit 102 is configured to control the power generation of the master solar panel 101, and is typically a power converter such as a DC-DC converter. This master power generation control unit 102 receives the power generated by the master solar panel 101, and converts the received generated power to a predetermined voltage and outputs it in accordance with instructions (control) from an instruction unit 104. The output of the master power generation control unit 102 is supplied to the battery 50 and the load device 60.

[0015] The sensor 103 is a component for acquiring the power generation state of the master solar panel 101. This sensor 103 can acquire physical quantities such as the output voltage, output current, temperature, and generated power of the master solar panel 101 as the power generation state. The sensor 103 uses various detection elements such as a voltage sensor and a current sensor.

[0016] The instruction unit 104 is configured to control the master power generation control unit 102. The instruction unit 104 instructs the master power generation control unit 102 to control the master power generation control unit 102 based on the power generation state of the master solar panel 101 acquired by the sensor 103. This control includes control to output a voltage command value for power generation to the DC-DC converter constituting the master power generation control unit 102, and MPPT control to perform a scan process to search for the maximum power point of the master solar panel 101. The instruction unit 104 also instructs the slave solar module 20 and the slave solar module 30 to carry out the control that it instructs the master power generation control unit 102 to.

[0017] The slave solar module 20 includes a slave solar panel 201 and a slave power generation control unit 202. The slave solar module 30 includes a slave solar panel 301 and a slave power generation control unit 302. In this embodiment, all of the slave solar modules provided in the solar charging system 1 have the same configuration.

[0018] Slave solar panel 201 and slave solar panel 301 are devices capable of generating power according to the amount of sunlight irradiated thereon, and are typically an assembly of solar battery cells.

[0019] Slave power generation control unit 202 is configured to control power generation by slave solar panel 201, and is typically a power converter such as a DC-DC converter. This slave power generation control unit 202 inputs the power generated by slave solar panel 201, and converts the input generated power to a predetermined voltage and outputs it in accordance with instructions (control) received from instruction unit 104 of master solar panel 101. The output of slave power generation control unit 202 is supplied to battery 50 and load device 60.

[0020] Slave power generation control unit 302 is configured to control the power generation of slave solar panel 301, and is typically a power converter such as a DC-DC converter. Slave power generation control unit 302 receives the power generated by slave solar panel 301, and converts the received power generation to a predetermined voltage and outputs it in accordance with instructions (control) received from instruction unit 104 of master solar panel 101. The output of slave power generation control unit 302 is supplied to battery 50 and load device 60.

[0021] In the solar charging system 1 according to this embodiment, the master solar panel 101 of the master solar module 10, the slave solar panel 201 of the slave solar module 20, and the slave solar panel 301 of the slave solar module 30 have a predetermined correlation in terms of solar radiation conditions. Examples of the predetermined correlation in terms of solar radiation conditions include the fact that the way in which the master solar panel 101 is exposed to sunlight matches or is close to the way in which the slave solar panel 201 and the slave solar panel 301 are exposed to sunlight (in terms of irradiation amount, irradiation angle, irradiation area, etc.), or that it is possible to estimate the way in which the slave solar panel 201 and the slave solar panel 301 are exposed to sunlight from the way in which the master solar panel 101 is exposed to sunlight, etc.

[0022] The master solar panel 101 and the slave solar panel 201 or 301 may be installed side by side in different locations in a planar manner, or may be installed three-dimensionally in the same location stacked on top of each other. Fig. 2A shows an example of an image in which the master solar panel 101 and the slave solar panel 201 or 301 are installed side by side on the roof of a vehicle (multi-system structure). Fig. 2B shows an example of an image in which the master solar panel 101 and the slave solar panel 201 or 301 are installed stacked on the roof of a vehicle (multi-junction structure). Note that, in addition to the roof, other locations where solar panels may be installed on a vehicle include the hood, back door, trunk, and windows.

[0023] For example, in the case of a multi-system structure (FIG. 2A) in which panels are installed side by side in different locations, if the normal direction and curvature of the surface of master solar panel 101 match or are close to the normal direction and curvature of the surface of slave solar panel 201 and slave solar panel 301, it can be said that there is a correlation in the solar radiation conditions. On the other hand, in the case of a multi-junction structure (FIG. 2B) in which panels are installed stacked in the same location, the normal direction and curvature of the surface of master solar panel 101 already match those of slave solar panel 201 and slave solar panel 301, so it can be said that there is a correlation in the solar radiation conditions. However, in the case of such a multi-junction structure, the amount of light that passes through the master solar panel 101 and reaches the slave solar panel 201 or the slave solar panel 301 is less than the amount of light received by the master solar panel 101. Therefore, it is a good idea to know in advance the light transmittance and light attenuation rate of the master solar panel 101 in order to estimate the amount of light received by the slave solar panel 201 or the slave solar panel 301 from the amount of light received by the master solar panel 101 (or vice versa).

[0024] Battery 50 is a secondary battery configured to be chargeable and dischargeable, such as a lithium ion battery or a lead storage battery. Battery 50 is connected to master solar module 10, slave solar module 20, and slave solar module 30, and is configured to be able to charge the power generated by master solar panel 101 via master power generation control unit 102, to be able to charge the power generated by slave solar panel 201 via slave power generation control unit 202, and to be able to charge the power generated by slave solar panel 301 via slave power generation control unit 302.

[0025] The load device 60 is connected to the battery 50 and is various types of equipment that operates on power supplied from the battery 50. The load device 60 does not necessarily have to be included as a component of the solar charging system 1.

[0026] In the solar charging system 1 of FIG. 1, an example is shown in which the operation of the two slave solar modules 20 and 30 is controlled by the master solar module 10, but the number of slave solar modules controlled by the master solar module 10 is not limited to this. Also, as exemplified in the solar charging system 2 of FIG. 3, there may be a plurality of master solar modules that control the slave solar modules. In FIG. 3, there may be a correlation in terms of solar radiation conditions between the master solar panel of the first master solar module 11 and the slave solar panels of the first slave solar modules 21 and 31. There may be a correlation in terms of solar radiation conditions between the master solar panel of the second master solar module 12 and the slave solar panels of the second slave solar modules 22, 32, and 42.

[0027] 1 shows a configuration in which a sensor (sensor 103) that detects the physical quantity of the solar panel is provided only in the master solar module 10, but a sensor that only detects information unrelated to power generation control of the solar panel may be provided in each slave solar module 20 or 30. For example, the slave solar module 20 or 30 may be provided with a temperature sensor intended to measure the temperature of the environment in which the solar panel is installed.

[0028] [control] Further referring to Fig. 4, the control performed in the solar charging system 1 including the master solar module 10 and the slave solar modules 20 and 30 will be described. Fig. 4 is a flowchart showing the procedure of the scan process control executed by the solar charging system 1 according to this embodiment. The scan process control illustrated in Fig. 4 is started, for example, when the solar charging system 1 is started, and is repeatedly executed until the solar charging system 1 is stopped.

[0029] (Step S401) The instruction unit 104 of the master solar module 10 judges whether it is time to execute a scan process of the master solar panel 101. This timing can be given in advance as a fixed timing so that the scan process can be executed periodically. If the instruction unit 104 judges that it is time to execute a scan process of the master solar panel 101 (step S401, Yes), the process proceeds to step S402.

[0030] (Step S402) The master power generation control unit 102 of the master solar module 10 performs a scan process on the master solar panel 101 based on instructions given by the instruction unit 104. Meanwhile, the slave power generation control unit 202 of the slave solar module 20 and the slave power generation control unit 302 of the slave solar module 30 continue to perform power generation control of the slave solar panels 201 and 301 using the current voltage command value. Once the master power generation control unit 102 has performed a scan process on the master solar panel 101, the process proceeds to step S403.

[0031] (Step S403) The instruction unit 104 of the master solar module 10 instructs the master power generation control unit 102 to control (voltage command value) based on the result of the scan process that has been performed. In response to this instruction, the master power generation control unit 102 performs power generation control of the new master solar panel 101 based on the result of the scan process. The instruction unit 104 also instructs the slave power generation control unit 202 of the slave solar module 20 and the slave power generation control unit 302 of the slave solar module 30 to perform control (voltage command value) based on the result of the scan process that has been performed. In this instruction, it is desirable to reflect the control amount that differs between the master solar panel 101 and the slave solar panels 201 and 301 based on the normal direction, curvature, light transmittance, light attenuation rate, etc. of the solar panel surface that are previously grasped. In response to this instruction, the slave power generation control unit 202 performs power generation control of the new slave solar panel 201 based on the result of the scan process, and the slave power generation control unit 302 performs power generation control of the new slave solar panel 301 based on the result of the scan process. After the power generation control of each solar module has been performed, the process returns to step S401.

[0032] <Actions and Effects> As described above, according to a solar charging system according to one embodiment of the present disclosure, for multiple solar modules that are correlated with solar radiation conditions, only the main solar module (master) is equipped with a sensor that acquires the power generation state of the solar panel and an instruction unit that instructs power generation control of the solar panel based on the power generation state acquired by the sensor, and the secondary solar modules (slave) control the power generation of the solar panel based on instructions from the instruction unit of the main solar module.

[0033] With this configuration, the instructions for power generation control of the solar panel in the main solar module (master) can be shared by several slave solar modules. Therefore, in the slave solar modules, the number of components such as sensors configured for power generation control of the solar panel can be reduced. This allows the cost and scale of the solar charging system to be reduced.

[0034] <Application Examples> In a configuration including a plurality of master solar modules, such as the solar charging system 2 illustrated in FIG. 3, it is also possible to perform applied power generation control of the solar panel, which will be described below.

[0035] For example, in a configuration including a first master solar module 11 and a second master solar module 12, a case where an abnormality such as a failure occurs in the sensor of the first master solar module 11 may be considered. In such a case, the control command of the second master solar module 12 may be controlled so as to be applicable to the first slave solar modules 21 and 31 under the control of the first master solar module 11 in which the abnormality occurs. In this control, it is necessary to electrically connect the control output of the first master solar module 11 and the control output of the second master solar module 12 via a switching element or the like. In addition, it is desirable to adjust the applied control command by multiplying it by a predetermined coefficient or giving a predetermined weighting depending on the difference between the solar radiation conditions for the first master solar module 11 and the solar radiation conditions for the second master solar module 12 so that appropriate power generation control is performed. The coefficients and weighting can be set based on differences in the temperature of the solar panels, the actual generated power, the location where the solar panels are arranged, and the like.

[0036] Although one embodiment of the present disclosure has been described above, the present disclosure can be understood as a solar charging system, a method executed by the solar charging system, a program for executing the method, a computer-readable non-transitory recording medium storing the program, and a vehicle equipped with a solar charging system. [Industrial Applicability]

[0037] The present disclosure can be used in a solar charging system equipped with multiple solar modules. [Explanation of symbols]

[0038] 1, 2 Solar charging system 10, 11, 12 Master Solar Module 20, 21, 22, 30, 31, 32, 42 Slave Solar Modules 50 Battery 60 Load equipment 101 Master Solar Panel 102 Master power generation control unit 103 Sensors 104 Instruction section 201, 301 Slave Solar Panels 202, 302 Slave power generation control unit

Claims

1. A solar charging system including a plurality of solar modules that generate electricity using sunlight, At least one master solar module of the plurality of solar modules is A master solar panel; A sensor for acquiring a power generation state of the master solar panel; an instruction unit that instructs power generation control of the master solar panel based on the power generation state acquired by the sensor; a master power generation control unit that controls power generation of the master solar panel in accordance with an instruction from the instruction unit, Among the plurality of solar modules, each of the slave solar modules other than the master solar module is A slave solar panel; a slave power generation control unit that controls the power generation of the slave solar panel using instructions from the instruction unit of the master solar module, Solar charging system.

2. The master solar module and the slave solar module to which the instruction unit issues an instruction to the slave power generation control unit have a correlation in terms of solar radiation conditions between the master solar panel and the slave solar panel. The solar charging system according to claim 1 .

3. The correlated state in the solar radiation conditions includes a state in which the way sunlight hits the master solar panel and the way sunlight hits the slave solar panel are the same or similar within a predetermined range. The solar charging system according to claim 2 .

4. The state having a correlation in the solar radiation condition includes a state in which it is possible to estimate how sunlight hits the slave solar panel from how sunlight hits the master solar panel. The solar charging system according to claim 2 .

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