In-vehicle solar charging control system, in-vehicle solar charging control method, and recording medium

Abstract

The present invention relates to an in-vehicle solar charging control system, an in-vehicle solar charging control method, and a recording medium. The in-vehicle solar charging control system of the present invention includes: a path switching unit provided in parallel with a first DC-DC converter on an electrical circuit (X) that connects a solar DC-DC converter to a first battery and through which electricity having output power flows; and a switching unit control unit that switches the path switching unit to a first state in which the output power is supplied to the first battery instead of being input to the first DC-DC converter, and a second state in which the output power is allowed to be input to the first DC-DC converter that is switched to a first operating state by a converter control unit.

Description

Technical Field

[0001] The present invention relates to an in-vehicle solar charging control system, an in-vehicle solar charging control method, and a recording medium. Background Art

[0002] An in-vehicle solar charging control system that supplies power generated by a solar panel to a battery via two DCDC converters is disclosed in Japanese Unexamined Patent Application Publication No. 2019-126219.

[0003] In the in-vehicle solar charging control system of Japanese Unexamined Patent Application Publication No. 2019-126219, the power generated by the solar panel is supplied to the battery after passing through two DCDC converters. Therefore, for the in-vehicle solar charging control system of Japanese Unexamined Patent Application Publication No. 2019-126219, the power loss caused by the DCDC converter is large. Summary of the Invention

[0004] The present invention aims to obtain an in-vehicle solar charging control system, an in-vehicle solar charging control method, and a recording medium that can reduce the power loss caused by the DCDC converter even in a configuration where two DCDC converters are provided between the solar panel and the battery.

[0005] The in-vehicle solar charging control system according to the first aspect of the present invention includes: a solar panel mounted on a vehicle; a solar DCDC converter to which the power generated by the solar panel is input; a first DCDC converter capable of inputting the output power that is the power output by the solar DCDC converter; a converter control unit that switches the first DCDC converter between a first operating state in which the voltage is reduced and power is output when the output power is input, and a first stop state in which no power is output; a first battery capable of charging the power output by the first DCDC converter in the first operating state; a path switching unit provided in parallel with the first DCDC converter on an electrical circuit that connects the solar DCDC converter and the first battery and through which the electrical current having the output power flows; and a switching unit control unit that switches the path switching unit between a first state in which the output power is supplied to the first battery instead of being input to the first DCDC converter, and a second state in which the output power is allowed to be input to the first DCDC converter switched to the first operating state by the converter control unit.

[0006] The in-vehicle solar charging control system according to the first aspect of the present invention includes a solar panel mounted on a vehicle, a solar DCDC converter to which the power output from the solar panel is input, and a first DCDC converter that can input the output power of the solar DCDC converter. The in-vehicle solar charging control system further includes: a converter control unit that switches the first DCDC converter between a first operating state in which the voltage is reduced and power is output after the output power is input, and a first stop state in which no power is output; and a first battery that can charge the power output from the first DCDC converter in the first operating state.

[0007] The in-vehicle solar charging control system further includes a path switching unit that is provided in parallel with the first DCDC converter on an electrical circuit that connects the solar DCDC converter and the first battery and through which the electrical current having the output power flows. The switching unit control unit switches the path switching unit between a first state in which the output power is supplied to the first battery instead of being input to the first DCDC converter, and a second state in which the output power is allowed to be input to the first DCDC converter that is switched to the first operating state by the converter control unit.

[0008] If the first DCDC converter becomes the first stop state and the path switching unit becomes the first state, the power generated by the solar panel is supplied to the first battery without passing through the first DCDC converter after being output from the solar DCDC converter. Therefore, the in-vehicle solar charging control system according to the first aspect can reduce the power loss caused by the DCDC converter even though it has a structure in which two DCDC converters are provided between the solar panel and the first battery.

[0009] The in-vehicle solar charging control system according to the first aspect includes a power amount acquisition unit that acquires the amount of power of the above-mentioned output power. When the amount of power of the output power acquired by the power amount acquisition unit is equal to or less than a threshold value, the switching unit control unit switches the path switching unit to the first state, and the converter control unit switches the first DCDC converter to the first stop state.

[0010] In the above structure, when the amount of power of the output power acquired by the power amount acquisition unit is equal to or less than the threshold value, the switching unit control unit switches the path switching unit to the first state, and the converter control unit switches the first DCDC converter to the first stop state. Therefore, when the amount of power of the output power is equal to or less than the threshold value, the generated power is supplied only to the first battery.

[0011] The in-vehicle solar charging control system according to the first embodiment includes: a required power amount acquisition unit that acquires the required power amount of the first battery as the threshold value; and a comparison unit that compares the power amount of the output power acquired by the power amount acquisition unit with the required power amount acquired by the required power amount acquisition unit. When supplying power equal to or less than the required power amount to the first battery, the first battery will not become overcharged. When the comparison unit determines that the power amount of the output power is greater than the required power amount, the switching unit control unit switches the path switching unit to the second state, and the converter control unit switches the first DC-DC converter to the first operating state.

[0012] In the above structure, when the comparison unit determines that the power amount of the output power is greater than the required power amount, the switching unit control unit switches the path switching unit to the second state, and the converter control unit switches the first DC-DC converter to the first operating state. On the other hand, when the power amount of the output power is equal to or less than the required power amount, the switching unit control unit switches the path switching unit to the first state, and the converter control unit switches the first DC-DC converter to the first stopped state. Therefore, power equal to or less than the required power amount is supplied to the first battery. Therefore, the first battery will not become overcharged.

[0013] The in-vehicle solar charging control system according to the first embodiment includes: a second DC-DC converter that can input the output power and is switched by the converter control unit to a second operating state in which the voltage is increased and power is output when the output power is input, and a second stopped state in which no power is output; a second battery that can charge the power output by the second DC-DC converter in the second operating state; and at least one auxiliary machine that is supplied with power from the first battery. When the vehicle is in a stopped state and a specified condition is satisfied when the generated power of the output power is greater than the required power amount, the second DC-DC converter switched to the second operating state by the converter control unit outputs power of the excess power amount obtained by subtracting the required power amount from the power amount of the output power to the second battery. When the specified condition is not satisfied, the converter control unit switches the first DC-DC converter to the first stopped state, switches the second DC-DC converter to the second stopped state, and the switching unit control unit switches the path switching unit to the first state.

[0014] In the above structure, when a specified condition that holds when the vehicle is in a parked state and the generated power for outputting power is greater than the required power amount holds, the second DC-DC converter switched to the second operating state by the converter control unit outputs the power of the excess power amount obtained by subtracting the required power amount from the power amount of the output power to the second battery. And the switching unit control unit switches the path switching unit to the second state, and the converter control unit switches the first DC-DC converter to the first operating state. Therefore, when the specified condition holds, power of an amount equal to or less than the required power amount is supplied to the first battery, and the power of the excess power amount can be stored in the second battery.

[0015] In the above structure, when the specified condition does not hold, the converter control unit switches the first DC-DC converter to the first stopped state, and switches the second DC-DC converter to the second stopped state, and the switching unit control unit switches the path switching unit to the first state. Therefore, when the vehicle is in a traveling state, power of an amount greater than the required power amount is supplied to the first battery. However, when the vehicle is in a traveling state, the power consumption of the auxiliary machine supplied with power from the first battery is likely to be greater than when in a parked state. Therefore, in this case, even if power of an amount greater than the required power amount is supplied to the first battery, the risk of overcharging the first battery with power is small.

[0016] The in-vehicle solar charging control method according to the second aspect of the present invention is an in-vehicle solar charging control method implemented by an in-vehicle solar charging control system, the in-vehicle solar charging control system including: a solar panel mounted on a vehicle; a solar DC-DC converter to which power generated by the solar panel is input; a first DC-DC converter capable of switching between a first operating state in which voltage is reduced and power is output when power of the output power output from the solar DC-DC converter is input, and a first stopped state in which no power is output; a first battery capable of charging the power output from the first DC-DC converter in the first operating state; and a path switching unit provided in parallel with the first DC-DC converter on a circuit connecting the solar DC-DC converter and the first battery and through which the electric power having the output power flows, and capable of switching between a first state in which the output power is supplied to the first battery instead of being input to the first DC-DC converter, and a second state in which the output power is allowed to be input to the first DC-DC converter in the first operating state, wherein the in-vehicle solar charging control method includes: a step of determining whether the power amount of the output power is equal to or less than a threshold value; and a step of switching the path switching unit to the first state and switching the first DC-DC converter to the first stopped state when the power amount of the output power is equal to or less than the threshold value.

[0017] The recording medium according to the third aspect of the present invention stores a program that enables an in-vehicle solar charging control system to perform the following processes: The in-vehicle solar charging control system includes: a solar panel mounted on a vehicle; a solar DCDC converter to which the electric power generated by the solar panel is input; a first DCDC converter that can be switched to a first operating state in which the voltage is reduced and the electric power is output when the output electric power that is the output of the solar DCDC converter is input, and a first stop state in which no electric power is output; a first battery that can charge the electric power output by the first DCDC converter in the first operating state; and a path switching unit disposed in an electric circuit that connects the solar DCDC converter and the first battery and through which the electric current having the output electric power flows in parallel with the first DCDC converter. The path switching unit can be switched to a first state in which the output electric power is supplied to the first battery instead of being input to the first DCDC converter, and a second state in which the output electric power is allowed to be input to the first DCDC converter in the first operating state. The processes include: a process of determining whether the amount of the output electric power is equal to or less than a threshold; and a process of switching the path switching unit to the first state and switching the first DCDC converter to the first stop state when the amount of the output electric power is equal to or less than the threshold.

[0018] As described above, the in-vehicle solar charging control system, the in-vehicle solar charging control method, and the recording medium according to the present invention have an excellent effect of being able to reduce the power loss caused by the DCDC converter although there is a configuration in which two DCDC converters are provided between the solar panel and the battery.

[0019] Hereinafter, with reference to the accompanying drawings, the features, advantages, and technical and industrial significance of the exemplary embodiments of the present invention will be described. In the drawings, the same reference numerals denote the same elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of a vehicle equipped with the in-vehicle solar charging control system according to the embodiment.

[0021] Figure 2 is Figure 1 an overall view of the in-vehicle solar charging control system shown.

[0022] Figure 3 is Figure 2 a control block diagram of the solar ECU shown.

[0023] Figure 4 isFigure 1 Functional block diagram of the battery ECU shown

[0024] Figure 5 It represents Figure 2 Flowchart of the processing executed by the solar ECU shown

[0025] Figure 6 Overall diagram of the in-vehicle solar charging control system of the modified example Detailed implementation manners

[0026] Hereinafter, the implementation manners of the in-vehicle solar charging control system 10 (hereinafter, simply referred to as system 10), the in-vehicle solar charging control method, and the recording medium according to the present invention will be described with reference to the accompanying drawings

[0027] As Figure 1 and Figure 2 shown, the system 10 is mounted on the vehicle 12. The system 10 includes a solar panel 14, an auxiliary battery (first battery) 16, an auxiliary machine 17, a high-voltage battery (second battery) 18, a driving device, a solar ECU (Electronic Control Unit) 20, and a battery ECU 40

[0028] The solar panel 14 mounted on the roof of the vehicle 12 is a power generation device that generates electricity when receiving sunlight. The solar panel 14 is a solar cell module that is an aggregate of many solar cell units. The amount of power generation (kwh) and the output voltage of the power generated by the solar panel 14 have at least a correlation with the solar irradiance. The power generated by the solar panel 14 is output to the solar ECU 20 (solar DCDC converter 22). The maximum output voltage of the solar panel 14 in this embodiment is approximately 60V

[0029] The auxiliary battery 16 is a secondary battery that can be charged and discharged, for example, a lithium-ion battery or a lead-acid battery. If the power generated by the solar panel 14 is supplied to the auxiliary battery 16 via the solar ECU 20, the power is charged (stored) in the auxiliary battery 16. The auxiliary battery 16 is connected to at least one auxiliary machine 17 provided in the vehicle 12. These auxiliary machines 17 include, for example, headlights, interior lights, and air conditioners. Each auxiliary machine 17 operates by receiving power supply from the auxiliary battery 16. The rated voltage of the auxiliary battery 16 in this embodiment is, for example, 13V

[0030] The high-voltage battery 18 is a secondary battery capable of charging and discharging, such as a lithium-ion battery or a nickel-metal hydride battery. If the electric power generated by the solar panel 14 is supplied to the high-voltage battery 18 via the solar ECU 20, the high-voltage battery 18 is charged (electricity is stored). The high-voltage battery 18 is connected to various driving devices provided in the vehicle 12. These driving devices include, for example, a starter motor and an electric motor that serves as a driving source of the vehicle. These devices operate by receiving power supply from the high-voltage battery 18. The rated voltage of the high-voltage battery 18 in the present embodiment is a voltage higher than the maximum output voltage of the solar panel 14 (for example, 350V).

[0031] The solar ECU 20 connects the solar panel 14 to the auxiliary battery 16 and the high-voltage battery 18. The solar ECU 20 can supply the electric power generated by the solar panel 14 to the auxiliary battery 16 and the high-voltage battery 18. As Figure 3 described, the solar ECU 20 is configured to include a CPU (Central Processing Unit: processor) 20A, a ROM (Read Only Memory: read-only memory) 20B, a RAM (Random Access Memory: random access memory) 20C, a storage mechanism 20D, a communication I / F (InterFace: interface) 20E, and an input / output I / F 20F. The CPU 20A, the ROM 20B, the RAM 20C, the storage mechanism 20D, the communication I / F 20E, and the input / output I / F 20F are communicably connected to each other via a bus 20Z. The solar ECU 20 can obtain information about time from a timer (not shown).

[0032] The CPU 20A is a central processing unit that executes various programs and controls each part. That is, the CPU 20A reads a program from the ROM 20B or the storage mechanism 20D and executes the program using the RAM 20C as a work area. The CPU 20A controls each structure and performs various arithmetic processes according to the program recorded in the ROM 20B or the storage mechanism 20D.

[0033] The ROM 20B stores various programs and various data. The RAM 20C temporarily stores a program or data as a work area. The storage mechanism 20D is composed of a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive) and stores various programs and various data. The communication I / F 20E is an interface for the solar ECU 20 to communicate with other devices. The input / output I / F 20F is an interface for communicating with various devices. For example, the solar panel 14 is connected to the input / output I / F 20F.

[0034] In Figure 2An example of the functional structure of the solar ECU 20 is shown in a block diagram. The solar ECU 20 has a power amount acquisition unit 201, a comparison unit 202, a solar DCDC converter control unit 203, a first converter control unit (converter control unit) 204, a second converter control unit (converter control unit) 205, a switch control unit (switching unit control unit) 206, a vehicle state determination unit 207, and a solar panel control unit 208 as its functional structure. The power amount acquisition unit 201, the comparison unit 202, the solar DCDC converter control unit 203, the first converter control unit 204, the second converter control unit 205, the switch control unit 206, the vehicle state determination unit 207, and the solar panel control unit 208 are realized by the CPU 20A reading and executing a program stored in the ROM 20B. The solar DCDC converter control unit 203 controls the solar DCDC converter 22, the first converter control unit 204 controls the accessory DCDC converter (first DCDC converter) 26, the second converter control unit 205 controls the high-voltage DCDC converter (second DCDC converter) 28, and the switch control unit 206 controls the bypass circuit (path switching unit) 30.

[0035] As Figure 2 shown, the solar ECU 20 is configured to include a solar DCDC converter 22, a capacitor 24, an accessory DCDC converter 26, a high-voltage DCDC converter 28, and a bypass circuit 30. The solar ECU 20 has an electrical circuit 20X. The electrical circuit 20X has a first wiring 20X1 connected to the solar DCDC converter 22, and a second wiring 20X2 and a third wiring 20X3 branched from the first wiring 20X1. In the following description, the electrical power output from the solar DCDC converter 22 and flowing in the first wiring 20X1 is referred to as "output power Em".

[0036] The solar DC-DC converter 22 performs MPPT (Maximum Power Point Tracking) control and supplies the power generated in the solar panel 14 to the capacitor 24, the accessory DC-DC converter 26, the high-voltage DC-DC converter 28, and the bypass circuit 30. The solar DC-DC converter 22 adjusts (boosts or steps down) the voltage of the power input from the solar panel 14 to a specified voltage based on an instruction from the solar DC-DC converter control unit 203 and outputs it. The solar DC-DC converter 22 is a non-insulated type DC-DC converter in which the primary side and the secondary side are not insulated. During the power generation operation of the solar panel 14, the solar DC-DC converter 22 always continues to operate. In addition, a small power loss occurs in the solar DC-DC converter 22. Therefore, the amount of power Eme of the output power Em is slightly smaller than the amount of power of the power input from the solar panel 14 to the solar DC-DC converter 22. In addition, power losses also occur in the accessory DC-DC converter 26 and the high-voltage DC-DC converter 28.

[0037] The capacitor 24 can store the power generated by the solar panel 14 and voltage-converted by the solar DC-DC converter 22. The capacitor 24 is provided between the second wiring 20X2 and the ground potential. If the power flowing in the second wiring 20X2 in a state where the stored charge of the capacitor 24 is zero is supplied to the capacitor 24, the stored charge and voltage of the capacitor 24 gradually increase. And when the stored charge of the capacitor 24 reaches a specified amount, the intermediate voltage Vm, which is the voltage of the first wiring 20X1, the second wiring 20X2, and the third wiring 20X3, is maintained at a specified magnitude (about 25V in this embodiment).

[0038] The accessory DC-DC converter 26 is provided on the second wiring 20X2. During the power generation operation of the solar panel 14, the accessory DC-DC converter 26 switches between a first operating state in which the power input from the second wiring 20X2 is output to the accessory battery 16 while reducing the voltage based on an instruction from the first converter control unit 204, and a first stop state in which no power is output to the accessory battery 16. The accessory DC-DC converter 26 is a non-insulated type DC-DC converter in which the primary side and the secondary side are not insulated.

[0039] The high-voltage DCDC converter 28 is provided on the third wiring 20X3. During the power generation operation of the solar panel 14, the high-voltage DCDC converter 28 switches between a second operating state in which the voltage is increased and the power input from the third wiring 20X3 is output, and a second stop state in which no power is output, based on an instruction from the second converter control unit 205. The high-voltage DCDC converter 28 is an isolated type DCDC converter that insulates the primary side and the secondary side through a transformer. For the isolated type high-voltage DCDC converter 28 using a transformer, the boost ratio (the ratio of the primary side voltage to the secondary side voltage) at which the efficiency is maximized is determined by the turns ratio of the transformer (the ratio of the number of turns of the primary side coil to the number of turns of the secondary side coil). Specifically, if the boost ratio is made consistent with the number of turns of the transformer, the efficiency of the isolated type high-voltage DCDC converter 28 is maximized.

[0040] The bypass circuit 30 is provided on the second wiring 20X2 in parallel with the accessory DCDC converter 26. The bypass circuit 30 has a switch 31 that can move between an open position (refer to the solid line in Figure 2 ) and a closed position (refer to the hypothetical line in Figure 2 ). The switch 31 is, for example, a semiconductor relay. The position of the switch 31 is controlled by the switch control unit 206. When the switch 31 is in the open position, the power flowing in the electrical circuit 20X does not flow through the bypass circuit 30. On the other hand, when the switch 31 is in the closed position, the power flowing in the electrical circuit 20X is supplied to the accessory battery 16 via the bypass circuit 30. The state of the bypass circuit 30 when the switch 31 is in the closed position is referred to as the "first state", and the state of the bypass circuit 30 when the switch 31 is in the open position is referred to as the "second state". The initial state of the bypass circuit 30 is the first state.

[0041] Figure 1 The battery ECU 40 shown is connected to the accessory battery 16 and the high-voltage battery 18. The battery ECU 40 is configured to include a CPU, a ROM, a RAM, a storage mechanism, a communication I / F, and an input / output I / F. The CPU, ROM, RAM, storage mechanism, communication I / F, and input / output I / F are communicably connected to each other via a bus. The battery ECU 40 can obtain information about time from a timer (not shown).

[0042] In Figure 4An example of the functional structure of the battery ECU 40 is shown in a block diagram. The battery ECU 40 has a power information acquisition unit (required power amount acquisition unit) 401 as a functional structure. The power information acquisition unit 401 is implemented by the CPU reading and executing a program stored in the ROM. The power information acquisition unit 401 of the battery ECU 40 can acquire the current state of charge (SOC), capacity, upper limit value of the state of charge, voltage, and temperature of the auxiliary battery 16 and the high-voltage battery 18. The power information acquisition unit 401 calculates the required power amount Er (threshold value) of the auxiliary battery 16 based on the information about the SOC, capacity, upper limit value of the state of charge, voltage, and temperature. When supplying power less than or equal to the required power amount Er to the auxiliary battery 16, the auxiliary battery 16 will not become overcharged. Also, the solar ECU 20 and the battery ECU 40 are communicably connected via an in-vehicle network (not shown) so that they can exchange data with each other. That is, the information about the SOC, capacity, upper limit value of the state of charge, voltage, and temperature of the auxiliary battery 16 and the high-voltage battery 18 acquired by the power information acquisition unit 401, and the information about the required power amount Er of the auxiliary battery 16 are sent from the battery ECU 40 to the solar ECU 20.

[0043] (Function and effect)

[0044] Next, the function and effect of this embodiment will be described.

[0045] Use Figure 5 the flowchart of Figure 5 to describe the processing flow of the solar ECU 20 of this embodiment. The solar ECU 20 repeatedly executes the processing of the flowchart of

[0046] First, in step S10, the power amount acquisition unit 201 of the solar ECU 20 acquires the power amount Eme of the output power Em flowing in the first wiring 20X1. And the comparison unit 202 determines whether the power amount Eme acquired by the power amount acquisition unit 201 is less than or equal to the required power amount Er of the auxiliary battery 16 acquired by the power information acquisition unit 401 and sent to the solar ECU 20.

[0047] When it is determined to be yes in step S10, the solar ECU 20 proceeds to step S11, the first converter control unit 204 switches the auxiliary DCDC converter 26 to the first stop state, and the second converter control unit 205 switches the high-voltage DCDC converter 28 to the second stop state.

[0048] The solar ECU 20 that has completed the process of step S11 proceeds to step S12, and the switch control unit 206 sets the bypass circuit 30 to the first state. As a result, the voltages of the first wiring 20X1 and the second wiring 20X2 and the voltage of the capacitor 24 become equal to the voltage of the auxiliary battery 16 (e.g., 13V). Then, the output power Em is supplied to the auxiliary battery 16 through the first wiring 20X1, the second wiring 20X2, and the bypass circuit 30 (switch 31), and the power is stored in the auxiliary battery 16.

[0049] On the other hand, when the determination in step S10 is NO, the solar ECU 20 proceeds to step S13. In this case, the surplus power amount Esr, which is the power amount obtained by subtracting the required power amount Er of the auxiliary battery 16 from the power amount Eme of the output power Em, is greater than zero.

[0050] The vehicle state determination unit 207 of the solar ECU 20 that has proceeded to step S13 determines whether the vehicle 12 is in a parked state. For example, the vehicle state determination unit 207 determines whether the vehicle 12 is in a parked state based on at least one of the information about the position of the shift lever (not shown) received from a shift position sensor (not shown) and the information about the vehicle speed received from a vehicle speed sensor (not shown).

[0051] When the determination in step S13 is YES, the solar ECU 20 proceeds to step S14. The first converter control unit 204 of the solar ECU 20 that has proceeded to step S14 switches the auxiliary DCDC converter 26 to the first operating state, and the second converter control unit 205 switches the high-voltage DCDC converter 28 to the second operating state.

[0052] The solar ECU 20 that has completed the process of step S14 proceeds to step S15, and the switch control unit 206 switches the bypass circuit 30 to the second state. As a result, the power having the intermediate voltage Vm maintained at approximately 25V by the capacitor 24 is input from the second wiring 20X2 to the auxiliary DCDC converter 26 and input from the third wiring 20X3 to the high-voltage DCDC converter 28.

[0053] The voltage of the power supplied from the second wiring 20X2 to the auxiliary DCDC converter 26 is stepped down to approximately 13V by the auxiliary DCDC converter 26 and supplied to the auxiliary battery 16. The power amount of the power supplied from the second wiring 20X2 to the auxiliary DCDC converter 26 (auxiliary battery 16) is substantially the same as the required power amount Er. And the surplus power amount Esr of power is supplied from the third wiring 20X3 to the high-voltage DCDC converter 28.

[0054] When the determination in step S13 is NO, the solar ECU 20 proceeds to step S11.

[0055] When the processing of step S12 or S15 is completed, the solar ECU 20 temporarily ends Figure 5 the processing of the flowchart.

[0056] As described above, in the system 10 of the present embodiment, when the amount of power Eme obtained by the power amount acquisition unit 201 is less than or equal to the required power amount Er of the auxiliary battery 16 (step S10: YES), the first converter control unit 204 switches the auxiliary DCDC converter 26 to the first stop state, and the second converter control unit 205 switches the high-voltage DCDC converter 28 to the second stop state (step S11), and the switch control unit 206 switches the bypass circuit 30 (switch 31) to the first state (step S12). When the system 10 becomes this state, after the power (output power Em) generated by the solar panel 14 is output from the solar DCDC converter 22, it is supplied to the auxiliary battery 16 via the bypass circuit 30. In other words, after the power (output power Em) generated by the solar panel 14 is output from the solar DCDC converter 22, it is supplied to the auxiliary battery 16 without passing through the auxiliary DCDC converter 26. Therefore, although the system 10 has a configuration in which two DCDC converters (solar DCDC converter 22, auxiliary DCDC converter 26) are provided between the solar panel 14 and the auxiliary battery 16, power loss caused by the DCDC converter can be reduced.

[0057] Moreover, when the system 10 is in this state, power with an amount of power less than or equal to the required power amount Er is supplied to the auxiliary battery 16. When power with an amount of power less than or equal to the required power amount Er is supplied to the auxiliary battery 16, the auxiliary battery 16 does not become overcharged. Therefore, when the system 10 is in this state, the auxiliary battery 16 is not easily deteriorated.

[0058] Moreover, when the system 10 is in this state, the voltage of the output power Em output from the solar panel 14 varies according to the change in the sunshine amount. On the other hand, the voltages of the first wiring 20X1 and the second wiring 20X2 and the voltage of the capacitor 24 are maintained at a value equal to the voltage of the auxiliary battery 16 (for example, 13V). Therefore, compared with the case where the voltage of the first wiring 20X1 (and the voltages of the second wiring 20X2 and the capacitor 24) varies, the solar DCDC converter 22 can easily perform MPPT control.

[0059] Also in the system 10, when the amount of power Eme is greater than the required amount of power Er of the auxiliary battery 16 and the vehicle 12 is in a parked state (step S10: No, step S13: Yes), the specified condition is satisfied. And when this specified condition is satisfied, the first converter control unit 204 switches the auxiliary DCDC converter 26 to the first operating state, the second converter control unit 205 switches the high-voltage DCDC converter 28 to the second operating state (step S14), and the switch control unit 206 switches the bypass circuit 30 (switch 31) to the second state (step S15). Thereby, the high-voltage DCDC converter 28 switched to the second operating state inputs the power of the surplus power amount Esr obtained by subtracting the required power amount Er from the power amount Eme of the output power Em to the high-voltage battery 18. Therefore, a part of the power generated by the solar panel 14 can be stored in the high-voltage battery 18. And in this case, the power amount of the power below the required power amount Er is supplied to the auxiliary battery 16, so the auxiliary battery 16 is not easily deteriorated.

[0060] And in the case where the above-mentioned specified condition is not satisfied (step S10: Yes or step S13: No), the first converter control unit 204 switches the auxiliary DCDC converter 26 to the first stopped state, the second converter control unit 205 switches the high-voltage DCDC converter 28 to the second stopped state (step S11), and the switch control unit 206 switches the bypass circuit 30 (switch 31) to the first state (step S12). For example, when the vehicle 12 is in a traveling state (step S13: No), the power consumption of each auxiliary machine 17 supplied with power from the auxiliary battery 16 is likely to be greater than the case where the vehicle 12 is in a parked state. Therefore, in this case, even if the power of the power amount exceeding the required power amount Er is supplied to the auxiliary battery 16, the risk of the auxiliary battery 16 being over-supplied with power is small.

[0061] As described above, the system 10, the in-vehicle solar charging control method, and the program according to the embodiment have been described, but within the scope not departing from the gist of the present invention, the system 10, the in-vehicle solar charging control method, and the program can be appropriately designed and changed.

[0062] For example, step S10 can also be changed to a step of determining whether the power amount Eme of the output power Em is equal to or less than a specified value (threshold value). For example, in the case of less solar radiation, the power amount Eme becomes less than this specified value. Therefore, for example, when the power amount Eme of the output power Em is small due to less solar radiation, all the generated power is supplied only to one battery (auxiliary battery 16). Therefore, the power generated by the solar panel 14 can be efficiently charged to the auxiliary battery 16.

[0063] It can also be Figure 6The form of the illustrated modification implements the present invention. The system 10 of this modification includes two solar panels 14 and two solar DCDC converters 22. The power generated by one solar panel 14 is input to one solar DCDC converter 22, and the power generated by the other solar panel 14 is input to the other solar DCDC converter 22.

Claims

1. A vehicle-mounted solar charging control system, wherein, the vehicle-mounted solar charging control system includes: a solar panel mounted on a vehicle; a solar DCDC converter to which the electric power generated by the solar panel is input; a first DCDC converter capable of inputting the output power that is the output power of the solar DCDC converter; a converter control unit that switches the first DCDC converter to a first operating state in which the voltage is reduced and power is output when the output power is input, and a first stop state in which no power is output; a first battery capable of charging the power output by the first DCDC converter in the first operating state; a path switching unit provided in parallel with the first DCDC converter on an electrical circuit that connects the solar DCDC converter and the first battery and through which the electric current having the output power flows; a switching unit control unit that switches the path switching unit to a first state in which the output power is supplied to the first battery instead of being input to the first DCDC converter, and a second state in which the output power is allowed to be input to the first DCDC converter switched to the first operating state by the converter control unit; and a power amount acquisition unit that acquires the power amount of the output power, when the power amount of the output power acquired by the power amount acquisition unit is equal to or less than a threshold value, the switching unit control unit switches the path switching unit to the first state, and the converter control unit switches the first DCDC converter to the first stop state.

2. The vehicle-mounted solar charging control system according to claim 1, wherein, it includes: a required power amount acquisition unit that acquires the required power amount of the first battery as the threshold value; and a comparison unit that compares the power amount of the output power acquired by the power amount acquisition unit with the required power amount acquired by the required power amount acquisition unit, when power equal to or less than the required power amount is supplied to the first battery, the first battery will not be overcharged, when the comparison unit determines that the power amount of the output power is greater than the required power amount, the switching unit control unit switches the path switching unit to the second state, and the converter control unit switches the first DCDC converter to the first operating state.

3. The vehicle-mounted solar charging control system according to claim 2, wherein, it includes: a second DCDC converter capable of inputting the output power, which is switched by the converter control unit to a second operating state in which the voltage is increased and power is output when the output power is input, and a second stop state in which no power is output; a second battery capable of charging the power output by the second DCDC converter in the second operating state; and at least one auxiliary machine supplied with power from the first battery When a specified condition that holds when the vehicle is in a parked state and the generated power of the output power is greater than the required power amount holds, the second DC-DC converter switched to the second operating state by the converter control unit outputs the power of the excess power amount obtained by subtracting the required power amount from the power amount of the output power to the second battery. When the specified condition does not hold, the converter control unit switches the first DC-DC converter to the first stopped state, switches the second DC-DC converter to the second stopped state, and the switching control unit switches the path switching unit to the first state.

4. A vehicle-mounted solar charging control method is a vehicle-mounted solar charging control method implemented by a vehicle-mounted solar charging control system, and the vehicle-mounted solar charging control system includes: A solar panel mounted on a vehicle; A solar DC-DC converter to which the power generated by the solar panel is input; A first DC-DC converter that can be switched to a first operating state in which the voltage is reduced and power is output when the output power, which is the power output by the solar DC-DC converter, is input, and a first stopped state in which no power is output; The first battery is capable of charging the power output by the first DC-DC converter in the first operating state; And A path switching unit provided in parallel with the first DC-DC converter on an electrical circuit that connects the solar DC-DC converter and the first battery and through which the electrical power having the output power flows. The path switching unit can be switched to a first state in which the output power is supplied to the first battery instead of being input to the first DC-DC converter, and a second state in which the output power is allowed to be input to the first DC-DC converter in the first operating state. Wherein, The vehicle-mounted solar charging control method includes: A step of determining whether the power amount of the output power is below a threshold value; And A step of switching the path switching unit to the first state and switching the first DC-DC converter to the first stopped state when the power amount of the output power is below the threshold value.

5. A recording medium stores a program that enables a vehicle-mounted solar charging control system to execute the following processing, wherein The vehicle-mounted solar charging control system includes: A solar panel mounted on a vehicle; A solar DC-DC converter to which the power generated by the solar panel is input; A first DC-DC converter that can be switched to a first operating state in which the voltage is reduced and power is output when the output power, which is the power output by the solar DC-DC converter, is input, and a first stopped state in which no power is output; A first battery that can charge the power output by the first DC-DC converter in the first operating state; And A path switching unit is arranged in parallel with the first DC-DC converter on an electrical circuit that connects the solar DC-DC converter to the first battery and through which electricity with the output power flows. The path switching unit can be switched to a first state in which the output power is supplied to the first battery instead of being input to the first DC-DC converter, and a second state in which the output power is allowed to be input to the first DC-DC converter in the first operating state. The processing includes: processing for determining whether the amount of the output power is below a threshold; and processing for switching the path switching unit to the first state and switching the first DC-DC converter to the first stopped state when the amount of the output power is below the threshold.

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