Solar cell systems and vehicle systems

Abstract

To provide a solar cell system and a vehicle system that can protect a pedestrian from an electrical shock at the time of vehicle collision.SOLUTION: A solar cell system includes a first solar cell, a first electric circuit and a control unit. The first solar cell is installed to an engine hood of a vehicle. The first electric circuit is connected to the first solar cell. The control unit electrically connects the first solar cell to the first electric circuit when a travel speed of the vehicle is less than a first threshold and electrically disconnects the first solar cell from the first electric circuit when the travel speed of the vehicle is equal to or larger than the first threshold.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] FIELD Embodiments of the present invention relate to a solar cell system and a vehicle system. [Background technology]

[0002] In recent years, electric vehicles (EVs) and plug-in hybrid EVs (PHEVs) have gradually become more popular. The solar cell systems including solar cells installed in these vehicles are controlled specifically to increase power generation efficiency, but are not controlled to protect pedestrians from electric shock in the event of a vehicle collision, for example. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6183607 [Patent Document 2] Patent No. 5971175 [Non-patent literature]

[0004] [Non-Patent Document 1] "World's first! Volvo's pedestrian airbag explained." [online] [Retrieved September 5, 2022], Internet<URL: sweden-cars.jp / blog / > Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a solar cell system and a vehicle system that can protect pedestrians from electric shock in the event of a vehicle collision. [Means for solving the problem]

[0006] A solar cell system according to one embodiment includes a first solar cell, a first electric circuit, and a control unit. , a third solar cell, and a third electric circuit; The first solar cell is provided on a hood of a vehicle. The first electric circuit is connected to the first solar cell. The control unit electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold. The third solar cell is provided on a dashboard of the vehicle. The third electric circuit is connected to the third solar cell. The control unit electrically disconnects the third solar cell from the third electric circuit when there is an occupant in the vehicle when the vehicle is stopped, and electrically connects the third solar cell to the third electric circuit when there is no occupant in the vehicle when the vehicle is stopped. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram showing a schematic configuration example of a vehicle system according to the first embodiment. [Figure 2] FIG. 2 is a diagram for explaining control of the solar cell system according to the embodiment. [Figure 3] FIG. 3 is a flowchart showing an example of the operation of the control unit that performs the control shown in FIG. [Figure 4] FIG. 4 is a diagram for explaining control of the solar cell system according to the embodiment. [Figure 5] FIG. 5 is a flowchart showing an example of the operation of the control unit that performs the control shown in FIG. [Figure 6] FIG. 6 is a diagram for explaining the mounting location of the solar cell according to the embodiment. [Figure 7] FIG. 7 is a diagram for explaining control of the solar cell system according to the embodiment. [Figure 8] FIG. 8 is a block diagram showing a schematic configuration example of a vehicle system according to the second embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing a schematic configuration example of a tandem solar cell according to the same embodiment. [Figure 10] FIG. 10 is a diagram for explaining control of the solar cell system according to the embodiment. [Figure 11] FIG. 11 is a diagram illustrating a solar cell system according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment will be described with reference to the drawings. It should be noted that the disclosure is merely an example, and the invention is not limited to the contents described in the following embodiments. Modifications that can be easily conceived by a person skilled in the art are naturally included in the scope of the disclosure. For clearer explanation, the size, shape, etc. of each part may be changed from the actual embodiment and shown schematically in the drawings. In multiple drawings, corresponding elements may be given the same reference numerals, and detailed explanations may be omitted.

[0009] (First embodiment) 1 is a block diagram showing a schematic configuration example of a vehicle system 1 according to a first embodiment. As shown in FIG. 1, the vehicle system 1 includes a vehicle 2, a solar cell system 3 provided in the vehicle 2, and a sensor group 4 provided in the vehicle 2.

[0010] The vehicle 2 includes a drive battery 21 and a motor 22. The drive battery 21 is connected to, for example, the motor 22 and supplies power to drive the motor 22.

[0011] The solar cell system 3 includes a control unit 10, a solar cell 31, a circuit breaker 32, and a DC / DC converter 33 (electrical circuit). The control unit 10 is a general-purpose microcomputer equipped with a CPU, memory, input / output units, etc., and may be referred to as an ECU (Electronic Control Unit). The control unit 10 controls the operations of the circuit breaker 32 and the DC / DC converter 33.

[0012] The solar cell 31 is, for example, a single-layer solar cell that generates electricity with one cell. The solar cell 31 is configured by laminating multiple layers including a wide-gap light absorption layer (photoelectric conversion layer). Examples of the wide-gap light absorption layer include transparent oxide semiconductors (specifically, cuprous oxide (CuO) and the like), compound semiconductors, perovskite compounds, amorphous silicon, and the like. Note that the solar cell 31 in this embodiment may have any configuration as long as it can generate electricity in response to incident light. The solar cell 31 is provided, for example, on the hood of the vehicle 2.

[0013] The DC / DC converter 33 is connected to the drive battery 21 of the vehicle 2. The DC / DC converter 33 may be wirelessly connected to the drive battery 21 of the vehicle 2. The DC / DC converter 33 increases or decreases the voltage of the power generated by the solar cell 31, and supplies the increased or decreased voltage to the drive battery 21 to charge the drive battery 21. The circuit breaker 32 is provided between the solar cell 31 and the DC / DC converter 33, and as described above, its operation is controlled by the control unit 10. In accordance with instructions from the control unit 10, the circuit breaker 32 switches between electrically connecting the solar cell 31 and the DC / DC converter 33 and electrically disconnecting the solar cell 31 and the DC / DC converter.

[0014] The sensor group 4 provided in the vehicle 2 includes a collision detection sensor 41, a vehicle speed sensor 42, a precipitation sensor 43, a pressure sensor 44, and a seat belt sensor 45. The collision detection sensor 41 is, for example, an acceleration sensor that detects the acceleration of the vehicle 2 in the longitudinal direction, and is configured to detect a collision of the vehicle 2. The vehicle speed sensor 42 is a sensor that detects the traveling speed of the vehicle 2. The precipitation sensor 43 is, for example, a water droplet sensor that is configured to detect the presence or absence of precipitation. The pressure sensor 44 is provided in each seat in the vehicle 2, and is configured to detect whether an occupant is seated in the seat. The seat belt sensor 45 is configured to detect the fastening and unfastening state of a seat belt provided in each seat of the vehicle 2. The control unit 10 acquires the detection results of the sensor group 4 and controls the operation of the solar cell system 3 based on the detection results. In this embodiment, the sensor group 4 provided in the vehicle 2 includes a collision detection sensor 41, a vehicle speed sensor 42, a precipitation sensor 43, a pressure sensor 44, and a seat belt sensor 45, but the various sensors provided in the vehicle 2 are not limited to these, and other sensors may also be provided in the vehicle 2.

[0015] Incidentally, the solar cell 31 provided on the hood of the vehicle 2 may be damaged when the vehicle 2 collides with a pedestrian. In this case, if the live part of the solar cell 31 becomes exposed and comes into contact with the pedestrian, the pedestrian may receive an electric shock. Even if the exposed live part does not come into direct contact with the pedestrian, the live part may come into indirect contact with the pedestrian via the vehicle body, resulting in the pedestrian receiving an electric shock.

[0016] For this reason, the solar cell system 3 according to this embodiment switches between connection and disconnection between the solar cell 31 and the DC / DC converter 33 depending on the traveling speed of the vehicle 2 to prevent the pedestrian from receiving the electric shock. Specifically, as shown in FIG. 2 , when the traveling speed of the vehicle 2 is below a preset first threshold, the solar cell 31 is unlikely to be damaged even if the vehicle 2 comes into contact with a pedestrian. Therefore, the solar cell system 3 electrically connects the solar cell 31 to the DC / DC converter 33 and charges the drive battery 21 provided in the vehicle 2. On the other hand, when the traveling speed of the vehicle 2 is equal to or greater than the preset first threshold, the solar cell 31 is likely to be damaged when the vehicle 2 comes into contact with a pedestrian. There is also a high possibility that a live part of the solar cell 31 will be exposed and come into contact with the pedestrian or the vehicle body. Therefore, the solar cell system 3 electrically disconnects the solar cell 31 from the DC / DC converter 33 to prevent the pedestrian from receiving the electric shock. Note that this embodiment assumes that the first threshold is set to 20 km / h (20 km per hour), but the first threshold is not limited to this value.

[0017] Fig. 3 is a flowchart showing an example of the operation of the control unit 10 that performs the control shown in Fig. 2. As shown in Fig. 3, when the control unit 10 acquires speed information from the vehicle speed sensor 42 provided in the vehicle 2 (step S1), it determines whether the traveling speed of the vehicle 2 indicated by the acquired speed information is equal to or greater than a first threshold value (step S2).

[0018] If it is determined as a result of the processing in step S2 that the traveling speed of the vehicle 2 is less than the first threshold value (No in step S2), the control unit 10 controls the operation of the breaker device 32 so that the solar cell 31 and the DC / DC converter 33 are electrically connected (step S3). That is, the power generated by the solar cell 31 is stepped up or down by the DC / DC converter 33 and supplied to the drive battery 21. This allows the drive battery 21 to be charged.

[0019] On the other hand, as a result of the processing in step S2, if it is determined that the traveling speed of the vehicle 2 is equal to or greater than the first threshold value (Yes in step S2), the control unit 10 controls the operation of the circuit breaker 32 so that the solar cell 31 and the DC / DC converter 33 are electrically disconnected (step S4). This prevents voltage and current from being generated between the solar cell 31 and the DC / DC converter 33, so that even if the vehicle 2 collides with a pedestrian and a live part of the solar cell 31 is exposed and comes into contact with the pedestrian or the vehicle body, the pedestrian can be prevented from receiving an electric shock.

[0020] In the above-described embodiment, the control unit 10 switches the connection / disconnection state between the solar cell 31 and the DC / DC converter 33 depending on the traveling speed of the vehicle 2. However, the control unit 10 may switch the connection / disconnection state between the solar cell 31 and the DC / DC converter 33 taking into consideration not only the traveling speed of the vehicle 2 but also the presence or absence of precipitation.

[0021] FIG. 4 is a diagram illustrating the control of the solar cell system 3 based on the traveling speed of the vehicle 2 and the presence or absence of precipitation. When precipitation is present, the possibility of a pedestrian being electrocuted increases if the vehicle 2 collides with the pedestrian, and the power generation efficiency of the solar cell 31 is also reduced due to the influence of rain clouds. For this reason, as shown in FIG. 4(a), the solar cell system 3 electrically disconnects the solar cell 31 from the DC / DC converter 33 regardless of the traveling speed of the vehicle 2 to prevent the pedestrian from being electrocuted. On the other hand, as shown in FIG. 4(b), when there is no precipitation, the solar cell system 3 performs control according to the traveling speed of the vehicle 2. Specifically, similar to the control shown in FIG. 2, when the traveling speed of the vehicle 2 is less than a first threshold, the solar cell 31 and the DC / DC converter 33 are electrically connected, and when the traveling speed of the vehicle 2 is equal to or greater than the first threshold, the solar cell 31 and the DC / DC converter 33 are electrically disconnected.

[0022] Fig. 5 is a flowchart showing an example of the operation of the control unit 10 that performs the control shown in Fig. 4. As shown in Fig. 5, when the control unit 10 acquires precipitation information from the precipitation sensor 43 provided in the vehicle 2 (step S11), it determines whether or not precipitation is occurring based on the acquired precipitation information (step S12).

[0023] As a result of the processing in step S12, if it is determined that precipitation is occurring (Yes in step S12), the control unit 10 controls the operation of the circuit breaker 32 so that the solar cell 31 and the DC / DC converter 33 are electrically disconnected (step S13). This prevents voltage and current from occurring between the solar cell 31 and the DC / DC converter 33, thereby preventing the above-mentioned electric shock to pedestrians.

[0024] On the other hand, if it is determined as a result of the processing in step S12 that there is no precipitation (No in step S12), the control unit 10 acquires speed information from the vehicle speed sensor 42 installed in the vehicle 2 (step S14), and determines whether the traveling speed of the vehicle 2 indicated by the acquired speed information is equal to or greater than the first threshold value (step S15).

[0025] As a result of the processing in step S15, if it is determined that the traveling speed of the vehicle 2 is equal to or greater than the first threshold value (Yes in step S15), the control unit 10 executes the processing in step S13 described above. That is, the control unit 10 controls the operation of the circuit breaker 32 so that the solar cell 31 and the DC / DC converter 33 are electrically disconnected.

[0026] On the other hand, if the processing result of step S15 determines that the traveling speed of the vehicle 2 is less than the first threshold value (No in step S15), the control unit 10 controls the operation of the circuit breaker 32 so that the solar cell 31 and the DC / DC converter 33 are electrically connected (step S16), and ends this series of operations.

[0027] In the above-described embodiment, it is assumed that the solar cell 31 is provided on the hood of the vehicle 2, and the control of the solar cell system 3 including the solar cell 31 provided on the hood of the vehicle 2 has been described. However, as shown in Fig. 6 , the solar cell 31 may be further provided on the roof or back door of the vehicle 2, the dashboard inside the vehicle, etc. In the following, for convenience, the elements included in the solar cell system 3 including the solar cell 31 provided on the hood of the vehicle 2 will be described with the suffix "a" added to the end, the elements included in the solar cell system 3 including the solar cell 31 provided on the roof or back door of the vehicle 2 will be described with the suffix "b" added to the end, and the elements included in the solar cell system 3 including the solar cell 31 provided on the dashboard of the vehicle 2 will be described with the suffix "c" added to the end.

[0028] FIG. 7 is a diagram illustrating the control of the solar cell system 3a including the solar cell 31a provided on the hood of the vehicle 2, the control of the solar cell system 3b including the solar cell 31b provided on the roof or back door of the vehicle 2, and the control of the solar cell system 3c including the solar cell 31c provided on the dashboard of the vehicle 2. Note that FIG. 7 assumes a case in which, in addition to the first threshold described above, a second threshold higher than the first threshold is set as a threshold for the traveling speed of the vehicle 2. The second threshold is set to, for example, 50 km / h (50 km per hour). By setting multiple thresholds in this way, it is possible to more precisely control the switching between the connected / disconnected state of the solar cell 31 and the DC / DC converter 33, thereby achieving more efficient power generation than when a single threshold is set.

[0029] First, the control of the solar cell system 3a including the solar cell 31a provided on the hood of the vehicle 2 will be described. As already explained, when the traveling speed of the vehicle 2 is less than the first threshold (including when the vehicle 2 is stopped), the solar cell 31a is unlikely to be damaged even if the vehicle 2 collides with a pedestrian. Therefore, the solar cell system 3a electrically connects the solar cell 31a to the DC / DC converter 33a to charge the drive battery 21 provided in the vehicle 2.

[0030] If the traveling speed of the vehicle 2 is equal to or greater than the first threshold and less than the second threshold, there is a high possibility that the solar cell 31a will be damaged if the vehicle 2 comes into contact with a pedestrian, and that the live part of the solar cell 31a will be exposed and come into contact with the pedestrian or the vehicle body. Therefore, the solar cell system 3a electrically disconnects the solar cell 31a from the DC / DC converter 33a to prevent the pedestrian from receiving an electric shock.

[0031] When the traveling speed of vehicle 2 is equal to or greater than the second threshold, there is a high possibility that vehicle 2 is not on a road where pedestrians can travel, but on a motorway or expressway where pedestrians do not travel. In other words, when the traveling speed of vehicle 2 is equal to or greater than the second threshold, there is a low possibility that vehicle 2 will collide with a pedestrian. For this reason, solar cell system 3a electrically connects solar cell 31a and DC / DC converter 33a to charge drive battery 21 provided in vehicle 2.

[0032] Next, the control of the solar cell system 3b including the solar cells 31b provided on the roof or back door of the vehicle 2 will be described. Unlike the solar cell 31a mounted on the hood, the solar cell 31b mounted on the roof or back door of the vehicle 2 is unlikely to come into contact with the pedestrian even if the vehicle 2 collides with a pedestrian and the live part of the solar cell 31b is exposed. However, there is a possibility that the exposed live part may come into contact with the vehicle body, and the live part may come into indirect contact with the passengers inside the vehicle via the vehicle body. This could result in electric shock to the passengers. For this reason, the solar cell system 3b, including the solar cell 31b mounted on the roof or back door of the vehicle 2, performs control to prevent electric shock to the passengers inside the vehicle.

[0033] Specifically, when the traveling speed of the vehicle 2 is less than the first threshold (including when the vehicle 2 is stopped), the solar cell 31b is unlikely to be damaged even if the vehicle 2 collides with a pedestrian. Therefore, the solar cell system 3b electrically connects the solar cell 31b to the DC / DC converter 33b, and charges the drive battery 21 provided in the vehicle 2.

[0034] If the traveling speed of the vehicle 2 is equal to or greater than the first threshold and less than the second threshold, there is a high possibility that the solar cell 31b will be damaged if the vehicle 2 comes into contact with a pedestrian, and that the live parts of the solar cell 31b will be exposed and come into indirect contact with passengers inside the vehicle. For this reason, the solar cell system 3b electrically disconnects the solar cell 31b from the DC / DC converter 33b to prevent the passengers from receiving an electric shock.

[0035] When the traveling speed of vehicle 2 is equal to or greater than the second threshold, as described above, vehicle 2 is likely to be on a motorway or expressway where pedestrians do not travel, and the likelihood of vehicle 2 colliding with a pedestrian is low. However, there is a possibility that vehicle 2 may collide with a predetermined object other than a pedestrian (for example, another vehicle traveling in front of vehicle 2, an obstacle on the road, etc.). If vehicle 2 collides with a predetermined object while traveling at the second threshold or greater, solar cell 31b is likely to be damaged, and live parts of solar cell 31b are likely to be exposed and come into indirect contact with passengers inside the vehicle. For this reason, solar cell system 3b electrically disconnects solar cell 31b from DC / DC converter 33b to prevent the passengers from receiving an electric shock.

[0036] If the vehicle 2 collides with a predetermined object while the traveling speed is equal to or greater than the second threshold, the solar cell 31a mounted on the hood of the vehicle 2 is likely to be damaged, as are the solar cells 31b mounted on the roof or back door, and live parts of the solar cell 31a may be exposed and come into contact with the vehicle body. However, the solar cell 31a mounted on the hood is located farther from the passengers inside the vehicle than the solar cells 31b mounted on the roof or back door. Therefore, even if live parts of the solar cell 31a are exposed and come into contact with the vehicle body, the passengers are unlikely to receive an electric shock. Therefore, as described above, in the solar cell system 3a including the solar cell 31a mounted on the hood, the solar cell 31a and the DC / DC converter 33a are electrically connected to charge the drive battery 21, even when the traveling speed of the vehicle 2 is equal to or greater than the second threshold.

[0037] Furthermore, the control of the solar cell system 3c including the solar cell 31c provided on the dashboard of the vehicle 2 will be described. If the solar cell 31c installed on the dashboard of the vehicle 2 generates electricity while there are passengers inside the vehicle, there is a risk of electric shock to the passengers, regardless of whether the vehicle 2 has collided with a pedestrian. For this reason, the solar cell system 3c including the solar cell 31c performs control based on the presence or absence of passengers inside the vehicle, regardless of the traveling speed of the vehicle 2.

[0038] Specifically, when there are passengers inside the vehicle 2, the solar cell system 3c electrically disconnects the solar cell 31c from the DC / DC converter 33c to prevent the passengers from getting electric shock. On the other hand, when there are no passengers inside the vehicle 2, the solar cell system 3c electrically connects the solar cell 31c to the DC / DC converter 33c to charge the drive battery 21. The presence or absence of passengers is determined based on pressure information acquired from a pressure sensor 44 provided in each seat inside the vehicle, for example.

[0039] 7, when it is detected that the vehicle 2 has collided with a pedestrian or a predetermined object, all solar cell systems 3 electrically disconnect the solar cells 31 from the DC / DC converters 33 to prevent the pedestrian and passengers from getting electric shock. The collision of the vehicle 2 is detected based on collision information acquired from the collision detection sensor 41, for example.

[0040] According to the first embodiment described above, the solar cell system 3 is equipped with a control unit 10 that controls the operation of the circuit breaker 32 to electrically disconnect the solar cell 31 and the DC / DC converter 33 in situations where there is a risk of electric shock to pedestrians and passengers, thereby making it possible to protect pedestrians and passengers from electric shock (ensuring the safety of pedestrians and passengers).

[0041] (Second embodiment) Next, a second embodiment will be described. The vehicle system 1 according to the second embodiment differs from the first embodiment in that the solar cell 31 provided in the vehicle 2 is a tandem solar cell including a top cell and a bottom cell. Below, differences from the first embodiment will be mainly described, and descriptions of similar parts to the first embodiment will be omitted.

[0042] As shown in FIG. 8, the solar cell system 3 of this embodiment includes a control unit 10, a top cell 31T constituting a solar cell 31, a circuit breaker 32T connected to the top cell 31T, a DC / DC converter 33T connected to the circuit breaker 32T, a bottom cell 31B constituting the solar cell 31, a circuit breaker 32B connected to the bottom cell 31B, and a DC / DC converter 33B connected to the circuit breaker 32B.

[0043] Both DC / DC converters 33T, 33B are connected to the drive battery 21 of the vehicle 2. The DC / DC converter 33T corresponding to the top cell 31T and the DC / DC converter 33B corresponding to the bottom cell 31B may be connected to multiple batteries of different voltages provided in the vehicle 2. For example, the DC / DC converter 33B corresponding to the bottom cell 31B may be connected to the drive battery, and the DC / DC converter 33T corresponding to the top cell 31T may be connected to a battery with a lower voltage than the drive battery. Alternatively, the DC / DC converter 33T corresponding to the top cell 31T may be connected to the drive battery, and the DC / DC converter 33B corresponding to the bottom cell 31B may be connected to a battery with a lower voltage than the drive battery.

[0044] The tandem solar cell 31 includes a top cell 31T and a bottom cell 31B, each of which generates electricity. The light absorption layer of the top cell 31T is made of, for example, cuprous oxide (CuO). The light absorption layer of the bottom cell 31B is made of, for example, crystalline silicon.

[0045] Fig. 9 is a cross-sectional view showing a schematic configuration example of a tandem solar cell 31. As shown in Fig. 9, the tandem solar cell 31 includes a top cell 31T and a bottom cell 31B, and the top cell 31T and the bottom cell 31B are bonded together with an insulating adhesive film F. If the top cell 31T is damaged and an active part of the top cell 31T is exposed, the insulating adhesive film F can prevent the active part from coming into contact with the bottom cell 31B or the vehicle body. Similarly, if the bottom cell 31B is damaged and an active part of the bottom cell 31B is exposed, the insulating adhesive film F can prevent the active part from coming into contact with the top cell 31T or a pedestrian.

[0046] The top cell 31T and the adhesive film F are formed of a transparent material to allow light to enter the bottom cell 31B. The power generated in each of the top cell 31T and the bottom cell 31B is supplied to the drive battery 21, charging the drive battery 21. As described above, the top cell 31T and the bottom cell 31B may each supply power to a plurality of batteries having different voltages provided in the vehicle 2.

[0047] As described in the first embodiment, if the vehicle 2 collides with a pedestrian and is damaged, the solar cell 31 provided on the hood of the vehicle 2 may cause an electric shock to the pedestrian. Also, if the vehicle 2 collides with a pedestrian and is damaged, the solar cell 31 provided on the roof or back door of the vehicle 2 may cause an electric shock to passengers inside the vehicle.

[0048] When the solar cell 31 installed in the vehicle 2 is a tandem type, it is the top cell 31T of the two cells constituting the solar cell 31 installed on the hood that is most likely to come into contact with pedestrians and cause electric shock to the pedestrians. When the solar cell 31 installed in the vehicle 2 is a tandem type, it is the bottom cell 31B of the two cells constituting the solar cell 31 installed on the roof or back door that is most likely to come into contact with the vehicle body and cause electric shock to passengers inside the vehicle. For this reason, the solar cell system 3 according to this embodiment performs different controls on the top cell 31T and the bottom cell 31B depending on the installation location of the tandem type solar cell 31. This makes it possible to generate electric power efficiently while preventing the above-mentioned electric shock to pedestrians and electric shock to passengers.

[0049] 10 is a diagram for explaining the control of the solar cell system 3 including the tandem solar cell 31. In the following, for convenience, the elements included in the solar cell system 3 including the solar cell 31 provided on the hood of the vehicle 2 will be described with the suffix "a" added to the end, the elements included in the solar cell system 3 including the solar cell 31 provided on the roof or back door of the vehicle 2 will be described with the suffix "b" added to the end, and the elements included in the solar cell system 3 including the solar cell 31 provided on the dashboard of the vehicle 2 will be described with the suffix "c" added to the end.

[0050] First, the control of the solar cell system 3a including the solar cell 31a provided on the hood of the vehicle 2 will be described. When the traveling speed of the vehicle 2 is below the first threshold (including when the vehicle 2 is stopped), the solar cell 31a is unlikely to be damaged even if the vehicle 2 collides with a pedestrian. For this reason, the solar cell system 3a including the solar cell 31a electrically connects the top cell 31Ta constituting the solar cell 31a to the DC / DC converter 33Ta, and electrically connects the bottom cell 31Ba constituting the solar cell 31a to the DC / DC converter 33Ba (that is, electrically connects both the top cell and the bottom cell to the corresponding DC / DC converter), to charge the drive battery 21 provided in the vehicle 2.

[0051] When the traveling speed of the vehicle 2 is equal to or greater than the first threshold and less than the second threshold, there is a high possibility that the solar cell 31a will be damaged if the vehicle 2 comes into contact with a pedestrian, and that an active portion of the top cell 31Ta constituting the solar cell 31a will be exposed and come into contact with the pedestrian. Therefore, the solar cell system 3a electrically disconnects the top cell 31Ta constituting the solar cell 31a from the DC / DC converter 33Ta to prevent the pedestrian from receiving an electric shock. On the other hand, because there is a low possibility that the bottom cell 31Ba constituting the solar cell 31a will come into contact with a pedestrian, the solar cell system 3a electrically connects the bottom cell 31Ba to the DC / DC converter 33Ba to charge the drive battery 21 provided in the vehicle 2.

[0052] When the traveling speed of the vehicle 2 is equal to or greater than the second threshold, as already described in the first embodiment, there is a high possibility that the vehicle 2 is on a motorway or expressway where pedestrians are not traveling. In other words, when the traveling speed of the vehicle 2 is equal to or greater than the second threshold, there is a low possibility that the vehicle 2 will collide with a pedestrian. For this reason, the solar cell system 3a including the solar cell 31a electrically connects the top cell 31Ta of the solar cell 31a to the DC / DC converter 33Ta, and electrically connects the bottom cell 31Ba of the solar cell 31a to the DC / DC converter 33Ba, to charge the drive battery 21 provided in the vehicle 2.

[0053] Next, the control of the solar cell system 3b including the solar cells 31b provided on the roof or back door of the vehicle 2 will be described. When the traveling speed of the vehicle 2 is below the first threshold (including when the vehicle 2 is stopped), the solar cell 31b is unlikely to be damaged even if the vehicle 2 collides with a pedestrian. For this reason, the solar cell system 3b electrically connects the top cell 31Tb constituting the solar cell 31b to the DC / DC converter 33Tb, and electrically connects the bottom cell 31Bb constituting the solar cell 31b to the DC / DC converter 33Bb (that is, electrically connects both the top cell and the bottom cell to the corresponding DC / DC converter), and charges the drive battery 21 provided in the vehicle 2.

[0054] When the traveling speed of the vehicle 2 is equal to or greater than the first threshold and less than the second threshold, there is a high possibility that the solar cell 31b will be damaged if the vehicle 2 comes into contact with a pedestrian, and that the live portion of the bottom cell 31Bb constituting the solar cell 31b will be exposed and come into indirect contact with passengers inside the vehicle. Therefore, the solar cell system 3b electrically disconnects the bottom cell 31Bb constituting the solar cell 31b from the DC / DC converter 33Bb to prevent the passengers from receiving an electric shock. Meanwhile, because there is a low possibility that the top cell 31Tb constituting the solar cell 31b will come into contact with the vehicle body, the solar cell system 3b electrically connects the top cell 31Tb to the DC / DC converter 33Tb to charge the drive battery 21 provided in the vehicle 2.

[0055] When the traveling speed of vehicle 2 is equal to or greater than the second threshold, as described above, vehicle 2 is likely to be on a motorway or expressway where pedestrians do not travel, and vehicle 2 is unlikely to collide with a pedestrian. However, vehicle 2 may collide with a predetermined object other than a pedestrian (e.g., another vehicle traveling in front of vehicle 2, an obstacle on the road, etc.). If vehicle 2 collides with a predetermined object while traveling at the second threshold or greater, solar cell 31b is likely to be damaged, and the live part of bottom cell 31Bb constituting solar cell 31b is likely to be exposed and come into indirect contact with passengers inside the vehicle. For this reason, solar cell system 3b electrically disconnects bottom cell 31Bb constituting solar cell 31b from DC / DC converter 33Bb to prevent the passengers from receiving an electric shock. On the other hand, since the top cell 31Tb constituting the solar cell 31b is unlikely to come into contact with the vehicle body, the solar cell system 3b electrically connects the top cell 31Tb to the DC / DC converter 33Tb and charges the drive battery 21 provided in the vehicle 2.

[0056] If the vehicle 2 collides with a predetermined object while the traveling speed is equal to or greater than the second threshold, the solar cell 31a mounted on the hood of the vehicle 2 is likely to be damaged, as are the solar cells 31b mounted on the roof or back door, and live parts of the top cell 31Ta and bottom cell 31Ba constituting the solar cell 31a may be exposed and come into contact with the vehicle body. However, since the solar cell 31a mounted on the hood is located farther from the passengers inside the vehicle than the solar cells 31b mounted on the roof or back door, even if the live parts of the top cell 31Ta and bottom cell 31Ba constituting the solar cell 31a are exposed and come into contact with the vehicle body, the passengers are unlikely to receive an electric shock as described above. Therefore, as described above, in the solar cell system 3a including the solar cell 31a mounted on the hood, even if the traveling speed of the vehicle 2 is equal to or higher than the second threshold, the top cell 31Ta constituting the solar cell 31a is electrically connected to the DC / DC converter 33Ta, and the bottom cell 31Ba constituting the solar cell 31a is electrically connected to the DC / DC converter 33Ba, thereby charging the drive battery 21.

[0057] Furthermore, the control of the solar cell system 3c including the solar cell 31c provided on the dashboard of the vehicle 2 will be described. If the solar cell 31c installed on the dashboard of the vehicle 2 generates electricity while there are passengers inside the vehicle, there is a risk of electric shock to the passengers, regardless of whether the vehicle 2 has collided with a pedestrian. For this reason, the solar cell system 3c including the solar cell 31c performs control based on the presence or absence of passengers inside the vehicle, regardless of the traveling speed of the vehicle 2.

[0058] Specifically, when there is an occupant inside the vehicle 2, the solar cell system 3c electrically disconnects the top cell 31Tc and the DC / DC converter 33Tc that constitute the solar cell 31c, and electrically disconnects the bottom cell 31Bc and the DC / DC converter 33Bc that constitute the solar cell 31c, to prevent the occupant from getting electric shock. On the other hand, when there is no occupant inside the vehicle 2, the solar cell system 3c electrically connects the top cell 31Tc and the DC / DC converter 33Tc that constitute the solar cell 31c, and electrically connects the bottom cell 31Bc and the DC / DC converter 33Bc that constitute the solar cell 31c, to charge the drive battery 21. The presence or absence of an occupant is determined based on pressure information acquired from a pressure sensor 44 provided in each seat inside the vehicle, for example.

[0059] 10, when it is detected that the vehicle 2 has collided with a pedestrian or a predetermined object, the top cells 31T and bottom cells 31B constituting the solar cells 31 included in all of the solar cell systems 3 are electrically disconnected from the corresponding DC / DC converters 33 to prevent the pedestrian and passengers from getting electric shock. The collision of the vehicle 2 is detected based on collision information acquired from the collision detection sensor 41, for example.

[0060] According to the second embodiment described above, the solar cell system 3 includes a tandem solar cell 31, and is equipped with a control unit 10 that controls the operation of the circuit breaker 32 so that, of the top cell 31T and bottom cell 31B constituting the solar cell 31, cells that may pose a risk of electric shock to pedestrians or passengers are electrically disconnected from the DC / DC converter 33, and cells that are unlikely to pose a risk of electric shock to pedestrians or passengers are electrically connected to the DC / DC converter 33. This makes it possible to achieve efficient power generation while protecting pedestrians and passengers from electric shock.

[0061] The following describes a modified example. (Variation) FIG. 11 is a diagram illustrating a solar cell system 3 according to a modified example. As shown in FIG. 11, the solar cell system 3 according to the modified example includes a solar cell 31 including multiple strings ST1 to ST3, each of which has a multiple number of solar cells connected in series; multiple blocking diodes 34 connected to each of the strings ST1 to ST3; a switch circuit 35; and a DC / DC converter 33. The switch circuit 35 is installed between the multiple blocking diodes 34 and the DC / DC converter 33, and switches between connecting the multiple strings ST1 to ST3 in parallel as shown in FIG. 11(a) and connecting the multiple strings ST1 to ST3 in series as shown in FIG. 11(b). The switch circuit 35 performs the above-described switching operation in accordance with an instruction from the control unit 10. Note that a breaker 32 may be further provided between the switch circuit 35 and the DC / DC converter 33.

[0062] When multiple strings ST1 to ST3 are connected in parallel, it is possible to reduce the output voltage of the solar cell 31 compared to when multiple strings ST1 to ST3 are connected in series. Therefore, for example, instead of "electrically disconnecting the solar cell 31 from the DC / DC converter 33" in the first and second embodiments, "switching to a parallel connection of the multiple strings ST1 to ST3" can be performed to reduce the output voltage of the solar cell 31 and protect pedestrians and passengers from electric shock. Alternatively, multiple strings ST1 to ST3 may be connected in parallel when there are passengers inside the vehicle 2, and may be connected in series when there are no passengers inside the vehicle 2, thereby protecting pedestrians and passengers from electric shock.

[0063] In this specification, it is assumed that the vehicle 2 is an EV or a PHEV, but the vehicle 2 may also be a railway vehicle, an automatic guided vehicle (AGV), construction machinery, etc. Furthermore, the bonnet of the vehicle 2 includes the engine compartment of the vehicle 2 and the front of the railway vehicle.

[0064] According to at least one of the embodiments described above, it is possible to provide a solar cell system and a vehicle system that can protect pedestrians from electric shock in the event of a vehicle collision.

[0065] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims.

[0066] The following are examples of solar cell systems and vehicle systems that can be obtained from this specification. [1] a first solar cell provided on a hood of the vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold. Solar cell system. [2] a second solar cell provided on at least one of a roof or a back door of the vehicle; a second electrical circuit connected to the second solar cell; The control unit electrically connecting the second solar cell and the second electric circuit when the traveling speed of the vehicle is less than the first threshold; When the traveling speed of the vehicle is equal to or greater than the first threshold, electrically disconnecting the second solar cell and the second electric circuit. [1] The solar cell system according to [1]. [3] a third solar cell provided on a dashboard of the vehicle; a third electrical circuit connected to the third solar cell; The control unit When the vehicle is stopped and there is a passenger in the vehicle, the third solar cell and the third electric circuit are electrically disconnected; When the vehicle is stopped and there is no passenger inside the vehicle, the third solar cell and the third electric circuit are electrically connected. The solar cell system according to [1] or [2]. [4] The first solar cell is a single-layer solar cell or a tandem solar cell. The solar cell system according to any one of [1] to [3]. [5] the first solar cell is a tandem solar cell including a top cell and a bottom cell, The control unit When the vehicle's traveling speed is less than the first threshold, electrically connecting both the top cell and the bottom cell to a first electric circuit corresponding to each cell; When the traveling speed of the vehicle is equal to or greater than the first threshold, electrically disconnecting the top cell from a corresponding first electric circuit and electrically connecting the bottom cell to the corresponding first electric circuit. The solar cell system according to any one of [1] to [4]. [6] The control unit When precipitation occurs, the first solar cell and the first electric circuit are electrically disconnected regardless of the traveling speed of the vehicle. The solar cell system according to any one of [1] to [5]. [7] The control unit a second threshold value that is greater than the first threshold value as a threshold value related to the traveling speed of the vehicle, and when the traveling speed of the vehicle is equal to or greater than the first threshold value and less than the second threshold value, electrically disconnecting the first solar cell and the first electric circuit; When the traveling speed of the vehicle is equal to or greater than the second threshold, electrically connect the first solar cell and the first electric circuit. The solar cell system according to any one of [1] to [6]. [8] the first solar cell is a tandem solar cell including a top cell and a bottom cell, The top cell and the bottom cell are bonded together via an insulating adhesive film. The solar cell system according to any one of [1] to [7]. [9] the first electric circuit is wirelessly connected to a drive battery provided in the vehicle; The solar cell system according to any one of [1] to [8].

[10] the first solar cell is a tandem solar cell including a top cell and a bottom cell, a first electric circuit corresponding to the top cell is connected to a first battery having a first voltage provided in the vehicle; a first electric circuit corresponding to the bottom cell is connected to a second battery provided in the vehicle and having a second voltage different from the first voltage; The solar cell system according to any one of [1] to [9].

[11] The control unit When a collision of the vehicle is detected, the first solar cell and the first electric circuit are electrically disconnected regardless of the traveling speed of the vehicle. The solar cell system according to any one of [1] to

[10] .

[12] the first solar cell includes a plurality of strings each including a plurality of solar cells; The control unit When there are passengers in the vehicle, the plurality of strings are connected in parallel; When there are no passengers in the vehicle, the plurality of strings are connected in series. The solar cell system according to any one of [1] to

[11] .

[13] Vehicles and a vehicle speed sensor capable of measuring the traveling speed of the vehicle; a first solar cell provided on a hood of the vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle measured by the vehicle speed sensor is lower than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle measured by the vehicle speed sensor is equal to or higher than the first threshold. Vehicle systems. [Explanation of symbols]

[0067] 1...vehicle system, 2...vehicle, 3...solar cell system, 4...sensor group, 10...control unit, 21...drive battery, 22...motor, 31...solar cell, 32...shutoff device, 33...DC / DC converter, 41...collision detection sensor, 42...vehicle speed sensor, 43...precipitation sensor, 44...pressure sensor, 45...seat belt sensor

Claims

1. a first solar cell provided on a hood of the vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold; a third solar cell provided on a dashboard of the vehicle; a third electric circuit connected to the third solar cell; The control unit When the vehicle is stopped and there is a passenger in the vehicle, the third solar cell and the third electric circuit are electrically disconnected; When the vehicle is stopped and there is no passenger inside the vehicle, the third solar cell and the third electric circuit are electrically connected. Solar cell system.

2. a second solar cell provided on at least one of a roof or a back door of the vehicle; a second electrical circuit connected to the second solar cell; The control unit When the traveling speed of the vehicle is less than the first threshold, electrically connecting the second solar cell and the second electric circuit; When the traveling speed of the vehicle is equal to or greater than the first threshold, electrically disconnecting the second solar cell and the second electric circuit. The solar cell system according to claim 1 .

3. The first solar cell is a single-layer solar cell or a tandem solar cell. The solar cell system according to claim 1 or 2.

4. A first solar cell provided on a hood of a vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold, the first solar cell is a tandem solar cell including a top cell and a bottom cell, The control unit When the vehicle's traveling speed is less than the first threshold, electrically connecting both the top cell and the bottom cell to a first electric circuit corresponding to each cell; When the traveling speed of the vehicle is equal to or greater than the first threshold, electrically disconnecting the top cell from a corresponding first electric circuit and electrically connecting the bottom cell to the corresponding first electric circuit. Solar cell system.

5. A first solar cell provided on a hood of a vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold, The control unit When precipitation is detected, the first solar cell and the first electric circuit are electrically disconnected regardless of the traveling speed of the vehicle. Solar cell system.

6. A first solar cell provided on a hood of a vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold, The control unit a second threshold value that is greater than the first threshold value as a threshold value related to the traveling speed of the vehicle, and when the traveling speed of the vehicle is equal to or greater than the first threshold value and less than the second threshold value, electrically disconnecting the first solar cell and the first electric circuit; When the traveling speed of the vehicle is equal to or greater than the second threshold, electrically connecting the first solar cell and the first electric circuit. Solar cell system.

7. the first solar cell is a tandem solar cell including a top cell and a bottom cell, The top cell and the bottom cell are bonded together via an insulating adhesive film. The solar cell system according to claim 1 or 2.

8. the first electric circuit is wirelessly connected to a drive battery provided in the vehicle; The solar cell system according to claim 1 or 2.

9. A first solar cell provided on a hood of a vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold, the first solar cell is a tandem solar cell including a top cell and a bottom cell, a first electric circuit corresponding to the top cell is connected to a first battery having a first voltage provided in the vehicle; a first electric circuit corresponding to the bottom cell is connected to a second battery provided in the vehicle and having a second voltage different from the first voltage; Solar cell system.

10. The control unit When a collision of the vehicle is detected, the first solar cell and the first electric circuit are electrically disconnected regardless of the traveling speed of the vehicle. The solar cell system according to claim 1 or 2.

11. A first solar cell provided on a hood of a vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle is less than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle is equal to or greater than the first threshold, the first solar cell includes a plurality of strings each including a plurality of solar cells; The control unit When there are passengers in the vehicle, the plurality of strings are connected in parallel; When there are no passengers in the vehicle, the plurality of strings are connected in series. Solar cell system.

12. Vehicles and a vehicle speed sensor capable of measuring the traveling speed of the vehicle; a first solar cell provided on a hood of the vehicle; a first electrical circuit connected to the first solar cell; a control unit that electrically connects the first solar cell and the first electric circuit when the traveling speed of the vehicle measured by the vehicle speed sensor is lower than a first threshold, and electrically disconnects the first solar cell and the first electric circuit when the traveling speed of the vehicle measured by the vehicle speed sensor is equal to or higher than the first threshold; a third solar cell provided on a dashboard of the vehicle; a third electric circuit connected to the third solar cell; The control unit When the vehicle is stopped and there is a passenger in the vehicle, the third solar cell and the third electric circuit are electrically disconnected; When the vehicle is stopped and there is no passenger inside the vehicle, the third solar cell and the third electric circuit are electrically connected. Vehicle systems.

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