Solar charging device

Abstract

To provide a solar charging device capable of reducing the cost of a solar power generation system and improving the mountability of components in a case where a plurality of solar panels are mounted.SOLUTION: In a solar charging device including a plurality of solar modules and an auxiliary battery, each of the plurality of solar modules includes: a solar panel; a first DC-DC converter that transforms power generated by the solar panel and supplies the transformed power to the auxiliary battery; and a first control unit that controls the first DC-DC converter.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a solar charging device that controls the supply of electric power generated by a solar panel mounted on a vehicle. [Background technology]

[0002] Patent document 1 discloses a solar charging control device that controls a solar DCDC converter, a high-voltage DCDC converter, and an auxiliary DCDC converter that are installed between a solar panel and a high-voltage battery and an auxiliary battery, and can suitably supply power generated by the solar panel to the high-voltage battery and the auxiliary battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-086302 Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration described in Patent Document 1, when adding solar panels, components such as a solar DC-DC converter, a high-voltage DC-DC converter, and an auxiliary DC-DC converter are required for each solar panel to be added. This increases the cost of the solar power generation system due to the increase in components, and there are still issues with the ease of installing the components.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a solar charging device that can reduce the cost of a solar power generation system and improve the ease of installing components when multiple solar panels are installed. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the disclosed technology is a solar charging device that includes a plurality of solar modules and an auxiliary battery, wherein each of the plurality of solar modules includes a solar panel, a first DC-DC converter that transforms the power generated by the solar panel and supplies it to the auxiliary battery, and a first control unit that controls the first DC-DC converter. [Effects of the Invention]

[0007] According to the solar charging device of the present disclosure, when multiple solar panels are installed, it is possible to reduce the cost of the solar power generation system and improve the ease of installing parts. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram of a solar charging device according to an embodiment of the present disclosure; [Figure 2] Charging control process flowchart executed by the solar charging device [Figure 3] A diagram explaining the supply status of electricity generated by multiple solar panels DETAILED DESCRIPTION OF THE INVENTION

[0009] The solar charging device according to the present disclosure integrates a solar panel, a solar DC-DC converter, and a solar control unit into a solar module. With this configuration, when adding solar panels, it is only necessary to add a solar module, which reduces the cost of the solar power generation system and improves the ease of component installation. 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 device 1 according to an embodiment of the present disclosure. The solar charging device 1 shown in Fig. 1 includes multiple solar modules 10A and 10B, an auxiliary battery 20, a drive battery 30, a battery bidirectional DC-DC converter (battery bidirectional DDC) 40, and a control unit 50. Note that in Fig. 1, connection lines for transmitting power are indicated by solid lines, and connection lines for transmitting control signals other than power are indicated by dashed lines. This solar charging device 1 is mounted on vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs).

[0011] The multiple solar modules 10A and 10B are each a power generation device that generates power when exposed to sunlight and outputs the generated power to an auxiliary battery 20 and an auxiliary load 100 connected to the multiple solar modules 10A and 10B. The solar module 10A includes a solar panel 11A, a solar DCDC converter (solar DDC) 12A, and a solar control unit 13A. The solar module 10B includes a solar panel 11B, a solar DCDC converter (solar DDC) 12B, and a solar control unit 13B.

[0012] Although Figure 1 illustrates an example in which solar module 10A and solar module 10B are connected in parallel, the number of solar modules connected in parallel is not limited to two, and may be three or more.

[0013] The solar panel 11A is a device that can generate power according to the amount of irradiation from sunlight, and is typically an assembly of solar cells. The power generated by the solar panel 11A is output to a solar DC-DC converter 12A. This solar panel 11A is installed, for example, on the roof of a vehicle. The solar panel 11B is a device that can generate power according to the amount of irradiation from sunlight, and is typically an assembly of solar cells. The power generated by the solar panel 11B is output to a solar DC-DC converter 12B. This solar panel 11B is installed, for example, on the back door of a vehicle.

[0014] The solar DCDC converter 12A is a power converter (first DCDC converter) that receives the power generated by the solar panel 11A, converts the received power to a predetermined voltage, and outputs the power. The solar DCDC converter 12A controls the conversion and output of the generated power according to instructions from the solar control unit 13A. The output of the solar DCDC converter 12A is supplied to the drive battery 30 via the auxiliary battery 20, the auxiliary load 100, and the battery bidirectional DCDC converter 40. The solar DCDC converter 12B is a power converter (first DCDC converter) that receives the power generated by the solar panel 11B, converts the received power to a predetermined voltage, and outputs the power. The solar DCDC converter 12B controls the conversion and output of the generated power according to instructions from the solar control unit 13B. The output of the solar DCDC converter 12B, together with the output of the solar DCDC converter 12A, is supplied to the drive battery 30 via the auxiliary battery 20, the auxiliary load 100, and the battery bidirectional DCDC converter 40.

[0015] The solar control unit 13A is configured with a processor such as a CPU, and is an electronic control device (first control unit) for controlling the operation of the solar DC-DC converter 12A. This solar control unit 13A can acquire information on the power generated by the solar panel 11A. The power generated by the solar panel 11A can be calculated, for example, from measurements of current sensors and voltage sensors (not shown) provided in the solar panel 11A and the solar control unit 13A. Furthermore, the solar control unit 13B is configured with a processor such as a CPU, and is an electronic control device (first control unit) for controlling the operation of the solar DC-DC converter 12B. This solar control unit 13B can acquire information on the power generated by the solar panel 11B. The power generated by the solar panel 11B can be calculated, for example, from measurements of current sensors and voltage sensors (not shown) provided in the solar panel 11B and the solar control unit 13B.

[0016] The solar control units 13A and 13B can acquire information about the power consumed by the auxiliary load 100 and the auxiliary battery 20. The power consumption by the auxiliary load 100 and the auxiliary battery 20 can be calculated, for example, from the power consumption calculated based on the output voltage and outflow current of the solar DCDC converter 12A and the power consumption calculated based on the output voltage and outflow current of the solar DCDC converter 12B.

[0017] Furthermore, solar control units 13A and 13B communicate (via CAN communication, LIN communication, etc.) with a control unit 50 that is provided independently of solar modules 10A and 10B and controls the power supply of the vehicle, and cooperate to control the charging and discharging of power in the vehicle. These solar control units 13A and 13B, together with the control unit 50, constitute a control unit that appropriately controls the solar-generated power and the power stored in each battery.

[0018] The auxiliary battery 20 is a rechargeable secondary battery, such as a lithium-ion battery or a lead-acid battery. The auxiliary battery 20 is connected to a solar DC-DC converter 12A of the solar module 10A so that it can be charged with power generated by the solar panel 11A. The auxiliary battery 20 is also connected to a solar DC-DC converter 12B of the solar module 10B so that it can be charged with power generated by the solar panel 11B. The auxiliary battery 20 is also connected to a battery bidirectional DC-DC converter 40 so that it can be charged with power stored in the drive battery 30. The auxiliary battery 20 can also supply the auxiliary load 100 with power required for the operation of the auxiliary load 100.

[0019] The drive battery 30 is a rechargeable secondary battery, such as a lithium-ion battery or a nickel-metal hydride battery. The drive battery 30 is connected to the solar DCDC converter 12A of the solar module 10A via a battery bidirectional DCDC converter 40 so that it can be charged with power generated by the solar panel 11A. The drive battery 30 is also connected to the solar DCDC converter 12B of the solar module 10B via a battery bidirectional DCDC converter 40 so that it can be charged with power generated by the solar panel 11B. The drive battery 30 is also connected to a main component (not shown) for driving the vehicle and can supply the power necessary to operate the main component. Examples of main components include a starter motor and a traction electric motor. The drive battery 30 is a high-voltage battery with a higher rated voltage than the auxiliary battery 20.

[0020] The battery bidirectional DCDC converter 40 is a power converter (second DCDC converter) that can convert input power into power of a predetermined voltage and output it based on instructions from the control unit 50. One end (called the primary side) of this battery bidirectional DCDC converter 40 is connected to the solar modules 10A and 10B, the auxiliary battery 20, and the auxiliary load 100, and the other end (called the secondary side) is connected to the drive battery 30. The battery bidirectional DCDC converter 40 can supply the parallel output power of the solar modules 10A and 10B connected to the primary side to the drive battery 30 connected to the secondary side (step-up operation), and can also supply power from the drive battery 30 connected to the secondary side to the auxiliary battery 20 and auxiliary load 100 connected to the primary side (step-down operation). During this power supply, the battery bidirectional DCDC converter 40 boosts the output voltage of the solar modules 10A and 10B, which is the input voltage on the primary side, to produce the output voltage on the secondary side (in boost operation), and also lowers the voltage of the driving battery 30, which is the input voltage on the secondary side, to produce the output voltage on the primary side (in step-down operation).

[0021] In this embodiment, the DC-DC converter inserted between the auxiliary battery 20 and the drive battery 30 is a battery bidirectional DC-DC converter 40 that is capable of both stepping up and stepping down. However, if power transfer from the auxiliary battery 20 to the drive battery 30 is not required, a DC-DC converter dedicated to stepping down that can transfer power only from the drive battery 30 to the auxiliary battery 20 may be inserted between the auxiliary battery 20 and the drive battery 30.

[0022] The control unit 50 is an electronic control device (second control unit) that includes a processor, memory, an input / output interface, etc., and controls the operation of the battery bidirectional DC-DC converter 40. For example, an HV-ECU that controls hybrid driving of the vehicle can be used as this control unit 50. The control unit 50 communicates (via CAN communication, LIN communication, etc.) with the solar control units 13A and 13B of the solar modules 10A and 10B, which together constitute a control unit, respectively, and controls the charging and discharging operations of power in the vehicle in cooperation with each other. The control performed by the solar control units 13A and 13B and the control unit 50 will be described later.

[0023] The auxiliary load 100 is a variety of auxiliary equipment mounted on a vehicle. The auxiliary load 100 operates by receiving power generated by the solar panels 11A and 11B of the solar modules 10A and 10B and power stored in the auxiliary battery 20. Examples of such auxiliary equipment include lighting equipment such as headlamps and interior lights, air conditioning equipment such as heaters and air conditioners, and systems for autonomous driving and advanced driving assistance.

[0024] [control] Next, the control performed by the solar charging device 1 according to this embodiment will be described with further reference to Figures 2 and 3. Figure 2 is a flowchart illustrating the charging control procedure executed by the solar control unit 13A, solar control unit 13B, and control unit 50, which constitute the control unit. Figure 3 is a diagram illustrating the supply state of power generated by the solar panel 11A and the solar panel 11B.

[0025] 2 is started when, for example, one or both of the solar control units 13A and 13B, which had some or all of their functions stopped (sleep), become capable of generating electricity through irradiation with sunlight, thereby activating (wake-up) the stopped functions. Below, the charging control will be explained using the example in which both solar control units 13A and 13B are activated (wake-up).

[0026] (Step S201) The solar control units 13A and 13B calculate the generated power Wgen, which is the power generated by all of the solar panels 11A and 11B. This generated power Wgen is the total generated power, which is the sum of the power generated by the solar panel 11A and the power generated by the solar panel 11B. Once the solar control units 13A and 13B have calculated the generated power Wgen of all of the solar panels 11A and 11B, the process proceeds to step S202.

[0027] (Step S202) The solar control units 13A and 13B determine whether the power generation Wgen of all solar panels 11A and 11B exceeds a predetermined first threshold Wsol. This determination is made to determine whether the solar panels 11A and 11B are generating enough power to perform efficient charging control. For example, if the power generation Wgen of the solar panels 11A and 11B is less than the power required for charging the solar modules 10A and 10B, power will be drawn from the auxiliary battery 20, resulting in more battery power being consumed than the power obtained through solar power generation, making charging control meaningless. Therefore, the first threshold Wsol can be set to a value equal to or greater than the power that allows charging control without drawing power from the auxiliary battery 20. If the solar control units 13A and 13B determine that the power generation Wgen of the solar panels 11A and 11B exceeds the first threshold Wsol (Wgen > Wsol) (step S202, Yes), the process proceeds to step S204. On the other hand, if the solar control units 13A and 13B determine that the power generation power Wgen of the solar panels 11A and 11B does not exceed the first threshold value Wsol (Wgen≦Wsol) (step S202, No), the process proceeds to step S203.

[0028] (Step S203) Since the solar control units 13A and 13B cannot perform efficient charging control using solar panel power generation, they stop the operation of some or all of their predetermined functions and go into sleep mode, thereby terminating the main charging control.

[0029] (Step S204) The solar control units 13A and 13B each request the control unit 50 to start power generation by the solar panels 11A and 11B, i.e., to start outputting the generated power Wgen to the auxiliary battery 20, etc. Note that this request to start power generation may be made by only one representative of the solar control units 13A and 13B. When the solar control units 13A and 13B request the solar panels 11A and 11B to start power generation, the process proceeds to step S205.

[0030] (Step S205) The control unit 50 receives a request from the solar control unit 13A and / or 13B to start power generation by the solar panels 11A and 11B and determines whether power generation by the solar panels 11A and 11B (output of generated power Wgen) is possible. This determination is made based on, for example, the state of the drive battery 30 and the operating state of the vehicle. If the control unit 50 determines that power generation by the solar panels 11A and 11B is possible (Yes in step S205), the process proceeds to step S206. On the other hand, if the control unit 50 determines that power generation by the solar panels 11A and 11B is not possible (No in step S205), the process proceeds to step S207.

[0031] (Step S206) The control unit 50 notifies the solar control units 13A and 13B that power generation by the solar panels 11A and 11B is permitted. When the control unit 50 notifies that power generation by the solar panels 11A and 11B is permitted, the process proceeds to step S208.

[0032] (Step S207) The control unit 50 notifies the solar control units 13A and 13B that power generation by the solar panels 11A and 11B is not permitted. When the control unit 50 notifies that power generation by the solar panels 11A and 11B is not permitted, the process proceeds to step S203.

[0033] (Step S208) The solar control units 13A and 13B start power generation by the solar panels 11A and 11B, respectively, based on the notification of permission for power generation by the solar panels 11A and 11B received from the control unit 50. This power generation can be achieved using well-known maximum power point tracking (MPPT) control or the like. FIG. 3 shows the paths along which power generated by each of the multiple solar panels 11A and 11B is supplied. As shown in FIG. 3, the power generated by the solar panel 11A and the power generated by the solar panel 11B can be simultaneously supplied to the auxiliary load 100, etc. When the solar control units 13A and 13B start power generation by the solar panels 11A and 11B, respectively, the process proceeds to step S209.

[0034] (Step S209) The solar control unit 13A controls the solar DCDC converter 12A so that the output voltage of the solar DCDC converter 12A is converted to a predetermined voltage. Furthermore, the solar control unit 13B controls the solar DCDC converter 12B so that the output voltage of the solar DCDC converter 12B is converted to a predetermined voltage. The predetermined voltage is typically the rated voltage of the auxiliary battery 20 (for example, 12V or 48V). Once the output voltages of the solar DCDC converters 12A and 12B have been controlled by the solar control units 13A and 13B, respectively, the process proceeds to step S201.

[0035] <Actions and Effects> As described above, the solar charging device 1 according to an embodiment of the present disclosure has a configuration in which the solar panel, the solar DC-DC converter, and the solar control unit are integrated as a solar module.

[0036] This configuration allows the number of solar modules (number of systems) to be freely changed to suit the vehicle configuration and target specifications, contributing to improved vehicle performance. Furthermore, adding solar panels requires only adding solar modules, reducing the cost of the solar power generation system and improving the ease of component installation. Furthermore, the solar control unit can individually control the power generated by each solar panel for each solar module.

[0037] The above describes one embodiment of the disclosed technology, but the present disclosure can be understood as not only a solar charging device, but also a charging control method, a control program for that method, a computer-readable non-transitory storage medium storing the control program, a vehicle equipped with a solar charging device, and the like. [Industrial Applicability]

[0038] The solar charging device of the present disclosure can be used in vehicles equipped with solar panels. [Explanation of symbols]

[0039] 1 Solar charging device 10A, 10B solar modules 11A, 11B solar panels 12A, 12B Solar DCDC Converter 13A, 13B Solar control unit 20 Auxiliary battery 30 Drive battery 40 Battery Bidirectional DCDC Converter 50 control section 100 Auxiliary load

Claims

1. A solar charging device including a plurality of solar modules and an auxiliary battery, Each of the plurality of solar modules comprises: Solar panels and a DC-DC converter that transforms the power generated by the solar panel and supplies the transformed power to the auxiliary battery; a first control unit that controls the DC-DC converter, When a total power generation amount, which is the sum of the power generation amounts of the solar panels, exceeds a total power, which is the sum of the power required for the charging operation of each of the solar modules, each of the first control units supplies the power generated by each of the solar panels to the auxiliary battery and the auxiliary load via each of the DCDC converters. Solar charging device.

2. Each of the first control units is requesting a second control unit that controls power exchange between the auxiliary battery and the drive battery to start outputting generated power; When the permission to start output is received from the second control unit, the supply of the generated power to the auxiliary battery and the auxiliary load is started. The solar charging device according to claim 1.

3. Each of the solar panels is installed at a different position, Each of the first control units individually controls the power generated by each of the solar panels. The solar charging device according to claim 1 or 2.

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