Fuel cell vehicle control device and fuel cell vehicle

Abstract

The present invention provides a control device for a fuel cell vehicle and a fuel cell vehicle. The control device for a fuel cell vehicle comprises: an output limiting unit for limiting the output of the fuel cell when a temperature-related value related to the temperature of the fuel cell indicates that the temperature is above a temperature threshold; a calculation unit for calculating the weight of a towed vehicle; a slope acquisition unit for acquiring the uphill slope at each point in a planned driving route; a prediction unit for predicting whether the output of the fuel cell is limited when the fuel cell vehicle travels on the planned driving route in a towing driving state; and a control unit for reporting a warning that there is a possibility that the vehicle speed of the fuel cell vehicle will decrease when the fuel cell vehicle travels on the planned driving route in the towing driving state, when it is predicted that the output of the fuel cell is limited.

Description

Technical Field

[0001] The present invention relates to a control device for a fuel cell vehicle and a fuel cell vehicle. Background Art

[0002] There are cases where the engine locomotive tows the towed vehicle to travel (for example, refer to Japanese Patent Application Laid-Open No. 2017-007442).

[0003] It is conceivable that the fuel cell vehicle tows the towed vehicle in the same manner as the engine vehicle. Here, if the fuel cell is maintained in a high output state, there is a possibility that the temperature of the fuel cell rises excessively. In such a case, the output of the fuel cell is limited in order to reduce the temperature of the fuel cell. Here, when the fuel cell vehicle tows a heavy towed vehicle while traveling on a steep uphill slope, there is a possibility that the fuel cell becomes hot and the output is limited, resulting in a reduction in vehicle speed. Summary of the invention

[0004] The present invention provides a fuel cell vehicle control device and a fuel cell vehicle capable of accurately predicting a decrease in vehicle speed of a fuel cell vehicle towing a towed vehicle and reporting the decrease in vehicle speed to a driver when the decrease in vehicle speed is predicted.

[0005] One embodiment of the present invention provides a control device for a fuel cell vehicle. The control device for a fuel cell vehicle is a control device for a fuel cell vehicle with a fuel cell as a power source and a motor as a driving source, wherein the control device comprises: an output limiting unit configured to limit the output of the fuel cell when a temperature-related value related to the temperature of the fuel cell indicates that the temperature is above a temperature threshold; a calculation unit configured to calculate the weight of a towed vehicle towed by the fuel cell vehicle; a slope acquisition unit configured to acquire the uphill slope at each point in a planned driving route of the fuel cell vehicle; a prediction unit configured to predict whether the output of the fuel cell is limited by the output limiting unit when the fuel cell vehicle travels on the planned driving route in a towing driving state in which the fuel cell vehicle tows the towed vehicle based on the weight of the towed vehicle and the uphill slope; and a control unit configured to report a warning that there is a possibility that the vehicle speed of the fuel cell vehicle will decrease when the fuel cell vehicle travels on the planned driving route in the towing driving state when the prediction unit predicts that the output of the fuel cell is limited through a reporting unit mounted on the fuel cell vehicle.

[0006] By predicting whether the output of the fuel cell of the fuel cell vehicle towing the towed vehicle is limited based on the weight of the towed vehicle and the uphill slope, the reduction in vehicle speed caused by the output limitation can be predicted with high accuracy. In addition, when a reduction in vehicle speed is predicted, it can be reported to the driver. In addition, "a warning reporting the possibility that the vehicle speed of the fuel cell vehicle may be reduced when the fuel cell vehicle is traveling on the predetermined driving route in the towing driving state" is not limited to the display and sound of such a message that must be output, and for example, it also includes outputting a buzzer indicating the above warning content from a speaker to the driver in advance, lighting a lighting device with a specified lighting pattern, and causing the display to display a specified symbol, etc.

[0007] In the above aspect, the prediction unit may be configured to predict that the output of the fuel cell is limited when the weight of the towed vehicle is equal to or greater than a weight threshold and at least one of the uphill gradients at each point is equal to or greater than a gradient threshold.

[0008] In the above-mentioned embodiment, there may be an information acquisition unit configured to acquire traction driving state information, the traction driving state information including the inclination angle of the road surface on which the fuel cell vehicle is driving in the traction driving state, and the torque of the motor when the fuel cell vehicle is driving on the road surface with the inclination angle in the traction driving state, and the calculation unit is configured to calculate the weight of the towed vehicle based on the traction driving state information.

[0009] In the above aspect, the towing running state information may include the vehicle speed of the fuel cell vehicle when the fuel cell vehicle is running on the road surface with the inclined angle in the towing running state.

[0010] In the above aspect, a storage unit may be provided that stores a map defining a relationship among the torque, the tilt angle, the vehicle speed, and the weight of the towed vehicle, and the calculation unit may be configured to calculate the weight of the towed vehicle with reference to the map.

[0011] In the above method, the traction driving state information may include the weight of the fuel cell vehicle, the air resistance of the fuel cell vehicle when the fuel cell vehicle is driving on the road surface with the above-mentioned inclined angle in the traction driving state, the acceleration of the fuel cell vehicle and the gear ratio of the transmission of the fuel cell vehicle.

[0012] In the above embodiment, a storage unit may be provided, which stores a calculation formula that specifies the relationship between the above torque, the above tilt angle, the weight of the above fuel cell vehicle, the above air resistance, the above acceleration, the above speed ratio and the weight of the above towed vehicle, and the above calculation unit is configured to calculate the weight of the above towed vehicle based on the above calculation formula.

[0013] In the above aspect, the control unit may be configured to issue a warning urging the vehicle to avoid the planned travel route through the reporting unit.

[0014] In the above aspect, the control unit may be configured to more emphatically issue a warning via the announcing unit as the weight of the towed vehicle increases.

[0015] In the above aspect, the control unit may be configured to more emphasize the warning by the notification unit as the upward slope gradient increases.

[0016] In the above aspect, the gradient acquisition unit may be configured to acquire the uphill gradient from a navigation device in which the planned travel route is set.

[0017] In the above aspect, the control unit may be configured to, when the prediction unit predicts that the output of the fuel cell is limited, cause the notification unit to notify a warning urging the user to change the planned travel route set in the navigation device.

[0018] In the above embodiment, the fuel cell vehicle may be a passenger car.

[0019] Another aspect of the present invention provides a fuel cell vehicle including a fuel cell, a motor, and a control device for the fuel cell vehicle.

[0020] According to the present invention, a fuel cell vehicle control device and a fuel cell vehicle can be provided which can accurately predict a decrease in vehicle speed of a fuel cell vehicle towing a towed vehicle and, when a decrease in vehicle speed is predicted, can report this to the driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Hereinafter, features, advantages, technical and industrial significance of exemplary embodiments of the present invention will be described with reference to the accompanying drawings, in which like reference numerals represent like components, wherein:

[0022] Figure 1 This is a structural diagram of a fuel cell vehicle.

[0023] Figure 2 The diagram shows a fuel cell vehicle and a towed vehicle towed by the fuel cell vehicle.

[0024] Figure 3 This is a flowchart showing an example of control executed by the ECU.

[0025] Figure 4 This is a flowchart showing an example of warning processing.

[0026] Figure 5A is an example of an image displayed on a dashboard display.

[0027] Figure 5B are other examples of images displayed on the instrument panel display.

[0028] Figure 5C are other examples of images displayed on the instrument panel display.

[0029] Figure 5D are other examples of images displayed on the instrument panel display.

[0030] Figure 5E are other examples of images displayed on the instrument panel display.

[0031] Figure 6 This is a diagram showing an example of an image displayed on the navigation display when a new guidance route is found.

[0032] Fig. 7A This is a flowchart showing a first modified example of the warning process.

[0033] Figure 7B This is a flowchart showing a second modified example of the warning process.

[0034] Fig. 8A are other examples of images displayed on the instrument panel display.

[0035] Figure 8B are other examples of images displayed on the instrument panel display.

[0036] Fig. 9 This is a flowchart showing an example of a calculation process of the towing weight.

[0037] Fig.10 This is a diagram showing an example of a plurality of maps that define the motor torque, vehicle speed, and traction weight for each inclination angle of the road surface. DETAILED DESCRIPTION

[0038] [Schematic Structure of Fuel Cell Vehicle 1]

[0039] Figure 1This is a structural diagram of a fuel cell vehicle 1. For the fuel cell vehicle 1, a fuel cell (hereinafter referred to as FC) 4 is a power source, and a motor 50 is a driving source. The fuel cell vehicle 1 includes an ECU (Electronic Control Unit) 3, FC4, a secondary battery (hereinafter referred to as BAT) 8, an oxidant gas supply system 10, a fuel gas supply system 20, a power control system 30, and a cooling system 40. In addition, the fuel cell vehicle 1 is provided with an accelerator opening sensor 6, an ignition switch 7, a dashboard display 9, a motor 50 for driving, a transmission 52, wheels 55, and a navigation device 60. The dashboard display 9 is provided at a position in the vehicle compartment that can be operated by the driver. The navigation device 60 has a touch panel navigation display 61 that can be operated by the driver.

[0040] FC4 receives the supply of oxidant gas and fuel gas to generate electricity. FC4 is stacked with multiple solid polymer electrolyte type single cells. The single cell has a power generation body, namely a membrane electrode assembly, in which electrodes are arranged on both sides of the electrolyte membrane, and a pair of separators that clamp the membrane electrode assembly. The electrolyte membrane is a solid polymer membrane formed by a fluorine resin material or a hydrocarbon resin material having a sulfonic acid group, and has good proton conductivity in a wet state. The electrode structure includes a carbon carrier and an ionomer that is a solid polymer having a sulfonic acid group and has good proton conductivity in a wet state. A catalyst (such as platinum or platinum-cobalt alloy, etc.) for promoting power generation reactions is carried on the carbon carrier. A manifold for supplying reaction gas and cooling water is provided in each single cell. The reaction gas flowing in the manifold is supplied to the power generation area of ​​each single cell via a gas flow path provided in each single cell.

[0041] The oxidant gas supply system 10 supplies air containing oxygen as an oxidant gas to FC4, and includes a supply pipe 11, an exhaust pipe 12, a bypass pipe 13, an air compressor 14, a bypass valve 15, an intercooler 16, and a back pressure valve 17. The supply pipe 11 is connected to the cathode inlet manifold of FC4. The exhaust pipe 12 is connected to the cathode outlet manifold of FC4. The bypass pipe 13 connects the supply pipe 11 and the exhaust pipe 12. The bypass valve 15 is provided at the connection portion between the supply pipe 11 and the bypass pipe 13. The bypass valve 15 switches the connection state between the supply pipe 11 and the bypass pipe 13. The air compressor 14, the bypass valve 15, and the intercooler 16 are sequentially arranged on the supply pipe 11 from the upstream side. The back pressure valve 17 is arranged on the exhaust pipe 12 at a position on the upstream side of the connection portion between the exhaust pipe 12 and the bypass pipe 13. The air compressor 14 supplies air containing oxygen as an oxidant gas to FC4 via the supply pipe 11. The oxidant gas supplied to FC4 is discharged through the discharge pipe 12. The intercooler 16 cools the oxidant gas supplied to FC4. The back pressure valve 17 adjusts the back pressure on the cathode side of FC4. The driving of the air compressor 14, the bypass valve 15 and the back pressure valve 17 is controlled by the ECU3. The ECU3 can adjust the flow rate of the oxidant gas supplied to FC4 by controlling the rotation speed of the air compressor 14. In addition, the ECU3 can adjust the flow rate of the oxidant gas supplied to FC4 and the flow rate of the bypassed oxidant gas by controlling the opening of the bypass valve 15 and the back pressure valve 17.

[0042] The fuel gas supply system 20 supplies hydrogen as fuel gas to FC4, and includes a tank 20T, a supply pipe 21, a discharge pipe 22, a circulation pipe 23, a tank valve 24, a pressure regulating valve 25, an injector (hereinafter referred to as INJ) 26, a gas-liquid separator 27, a drain valve 28, and a hydrogen circulation pump (hereinafter referred to as HP) 29. The tank 20T is connected to the anode inlet manifold of FC4 through the supply pipe 21. Hydrogen as fuel gas is stored in the tank 20T. The discharge pipe 22 is connected to the anode outlet manifold of FC4. The circulation pipe 23 communicates the gas-liquid separator 27 with the supply pipe 21. The tank valve 24, the pressure regulating valve 25 and INJ26 are arranged in sequence from the upstream side of the supply pipe 21. When the tank valve 24 is opened, the opening of the pressure regulating valve 25 is adjusted, and INJ26 injects fuel gas. Thus, fuel gas is supplied to FC4. A gas-liquid separator 27 and a drain valve 28 are arranged in the discharge pipe 22 in order from the upstream side. The gas-liquid separator 27 separates water from the fuel gas discharged from FC4 and stores it. The water stored in the gas-liquid separator 27 is discharged to the outside of the fuel cell vehicle 1 through the discharge pipe 22 due to the opening of the drain valve 28. The circulation pipe 23 is a pipe for refluxing the fuel gas to FC4. The end on the upstream side is connected to the gas-liquid separator 27 and is equipped with HP29. The fuel gas discharged from FC4 is appropriately pressurized by HP29 and guided to the supply pipe 21. The drive of the tank valve 24, the pressure regulating valve 25, INJ26, the drain valve 28 and HP29 is controlled by ECU3.

[0043] The power control system 30 includes a fuel cell DC / DC converter (hereinafter referred to as FDC) 32, a battery DC / DC converter (hereinafter referred to as BDC) 34, a motor inverter (hereinafter referred to as MINV) 38, and an auxiliary machine inverter (hereinafter referred to as AINV) 39. FDC32 controls the output current of FC4 based on the requested current value sent from ECU3, and adjusts the DC power from FC4 and outputs it to MINV38 and AINV39. BDC34 adjusts the DC power from BAT8 and outputs it to MINV38 and AINV39. The generated power of FC4 can be charged to BAT8. MINV38 converts the input DC power into three-phase AC power and supplies it to the motor 50. The motor 50 rotates the wheels 55 via the transmission 52, thereby allowing the fuel cell vehicle 1 to travel. The power of FC4 and BAT8 can be supplied to the load device via AINV39. The load device includes auxiliary machines for FC4 and auxiliary machines for the vehicle. The auxiliary machines for FC4 include the above-mentioned air compressor 14, bypass valve 15, back pressure valve 17, tank valve 24, pressure regulating valve 25, INJ 26, drain valve 28 and HP 29. The auxiliary machines for the vehicle include, for example, air conditioners, lighting devices, hazard warning lights and the like.

[0044] The cooling system 40 cools the FC4 by circulating the cooling water through a predetermined path. The cooling system 40 includes a supply pipe 41, a discharge pipe 42, a radiator 43, a water pump (hereinafter referred to as WP) 44, and a temperature sensor 4T. The supply pipe 41 is connected to the cooling water supply manifold of the FC4. The discharge pipe 42 is connected to the cooling water discharge manifold of the FC4. The radiator 43 is connected to the supply pipe 41 and the discharge pipe 42. The WP44 is arranged on the supply pipe 41. The WP44 circulates the cooling water as a refrigerant between the FC4 and the radiator 43 via the supply pipe 41 and the discharge pipe 42. The radiator 43 cools the cooling water discharged from the FC4 by exchanging heat with the outside air. The drive of the WP44 is controlled by the ECU3.

[0045] The temperature sensor 4T is provided on the discharge pipe 42, and detects the temperature of the cooling water before it is discharged from the FC4 and flows into the radiator 43. The ECU 3 obtains the detection result. As for the detection temperature of the temperature sensor 4T, since the temperature of the cooling water before it is discharged from the FC4 and flows into the radiator 43 is detected, the higher the detected temperature is, the higher the temperature of the FC4 is. The temperature of the cooling water detected by the temperature sensor 4T is an example of a temperature-related value related to the temperature of the FC4. In addition, as the temperature of the FC4, although the temperature of the cooling water detected by the temperature sensor 4T is used, it is not limited to this. For example, a sensor that directly detects the temperature of the FC4 may be provided, and the temperature of the FC4 is detected by the sensor.

[0046] ECU3 includes CPU (Central Processing Unit), ROM (Read Only Memory) and RAM (Random Access Memory). ECU3 is electrically connected to accelerator opening sensor 6, ignition switch 7, dashboard display 9, air compressor 14, bypass valve 15, back pressure valve 17, tank valve 24, pressure regulating valve 25, INJ26, drain valve 28, HP29, FDC32 and BDC34. ECU3 calculates the requested output to FC4 based on the detection value of accelerator opening sensor 6, the driving state of the auxiliary machine for the vehicle and the auxiliary machine for FC4, and the stored power of BAT8, and calculates the requested current value to FC4 based on the requested output. In addition, ECU3 controls the air compressor 14 and INJ26 according to the requested output to FC4 to control the flow rate of oxidant gas and fuel gas supplied to FC4, and controls FDC32 based on the requested current value of FC4, thereby controlling the output current of FC4. ECU3 is an example of a control device of fuel cell vehicle 1 that uniformly controls the entire fuel cell vehicle 1. The ECU 3 includes an output limiting unit, a calculation unit, a gradient acquisition unit, a prediction unit, and a control unit. In addition, the ECU 3 may include an information acquisition unit and a storage unit.

[0047] [Traction status]

[0048] Figure 2 1 is a diagram showing a fuel cell vehicle 1 and a towed vehicle 100 towed by the fuel cell vehicle 1. The fuel cell vehicle 1 is provided with a hook 2a protruding rearward at the rear end of the vehicle body 2. The hook 2a has, for example, a spherical hook ball 2b provided at the upper end of a columnar member erected in the vertical direction.

[0049] The towed vehicle 100 is also called a trailer, and includes a body 102, wheels 105, a coupling member 106, and a connector 108. The connector 108 is provided at the front end of the coupling member 106. A spherical recessed portion that covers the hook ball 2b is formed in the connector 108. The towed vehicle 100 is coupled to the fuel cell vehicle 1 so as to be able to turn by covering the hook ball 2b with the connector 108. The fuel cell vehicle 1 can travel in this state.

[0050] [Output Limit]

[0051] FC4 is cooled by cooling water as described above, but if FC4 is maintained in a high output state and the heat received by the cooling water from FC4 exceeds the heat dissipation capacity of the cooling water in the radiator 43, the temperature of the cooling water rises, and the temperature of FC4 also rises. If FC4 is too hot, there is a possibility of melting of the electrolyte membrane of FC4, etc. Therefore, when the detected temperature of the temperature sensor 4T becomes above a predetermined threshold, the ECU3 limits the output of FC4 so that the maximum output of FC4 is lower than the maximum rated output of FC4. This process is an example of a process performed by an output limiting unit that limits the output of FC4 when the temperature-related value related to the temperature of FC4 is expressed as the temperature of FC4 being above the temperature threshold. Specifically, ECU3 reduces the oxidant gas and fuel gas supplied to FC4 by reducing the rotation speed of the air compressor 14 and reducing the fuel gas injection amount of INJ26, etc., and limits the output of FC4 to reduce the temperature.

[0052] For example, when the fuel cell vehicle 1 tows the towed vehicle 100 as described above, the output of FC4 increases and becomes high temperature, and the output of FC4 is likely to be limited, depending on the weight of the towed vehicle 100 and the uphill slope of the road surface. As a result, the vehicle speed of the fuel cell vehicle 1 may be lower than when the output of FC4 is not limited. The ECU 3 in this embodiment performs control for making the driver of the fuel cell vehicle 1 towing the towed vehicle 100 recognize in advance that there is a possibility of a reduction in vehicle speed.

[0053] [Control of ECU 3]

[0054] Figure 3This is a flowchart showing an example of control executed by the ECU 3 . Figure 4 This is a flowchart showing an example of a warning process described later. Figure 5A to Figure 5E These are examples of images D1 to D5 displayed on the instrument panel display 9. When the instrument panel display 9 displays images D1 to D5, messages in the images may be outputted by sound from a speaker in the cabin of the fuel cell vehicle 1. The instrument panel display 9 and the speaker in the cabin are examples of a notification unit.

[0055] First, refer to Figure 3 The control performed by ECU3 is described. This control is repeatedly performed at predetermined intervals. ECU3 performs a calculation process (step S1) to calculate the weight of the towed vehicle that is expected to be towed by the fuel cell vehicle 1, that is, the towing weight f. The process of step S1 is an example of the process performed by the calculation unit. The specific calculation method of the towing weight f will be described later.

[0056] Next, the ECU 3 determines whether the fuel cell vehicle 1 is towing the towed vehicle based on the calculation result of the towing weight f (step S2). Specifically, if the calculated towing weight f is greater than a specified value, it is determined that the fuel cell vehicle 1 is towing the towed vehicle, and if the towing weight f is less than the specified value, it is determined that the fuel cell vehicle 1 is not towing the towed vehicle. Here, the specified value is set to a value greater than the maximum load of the fuel cell vehicle 1, for example. In the case of No in step S2, this control ends.

[0057] In the case of YES in step S2, ECU3 causes the dashboard display 9 to display an image D1 for urging the driver to check the towed vehicle 100 (step S3). The message "Trailer towing detected. Is there any error?" and "Yes", "No", and "Cancel" are displayed on the image D1. ECU3 determines whether the "Yes" area on the image D1 has been operated (step S4). In the case of NO in step S4, that is, when the "No" or "Cancel" area has been operated, ECU3 deletes the image D1 (step S5) and ends the control.

[0058] If the answer is yes in step S4, the ECU 3 determines whether the guidance route has been set for the navigation device 60 (step S6). If the answer is no in step S6, the ECU 3 displays an image D5 urging the driver to drive safely on the instrument panel display 9 (step S10). For example, the message "Please drive safely." is displayed on the image D5. The image D5 disappears after being displayed on the instrument panel display 9 for a predetermined time. Then, this control ends.

[0059] If YES in step S6, the ECU 3 acquires the uphill gradient r [%] at each point on the guidance route set by the navigation device 60 (step S7). The process of step S7 is an example of the process executed by the gradient acquisition unit.

[0060] Next, the ECU 3 determines whether the towing weight f is greater than or equal to a threshold value α (step S8). The threshold value α is, for example, 2000 kg. The threshold value α is an example of a weight threshold value. If the answer is NO in step S8, the process of step S10 is executed and the control ends.

[0061] In the case of yes in step S8, ECU3 determines whether there is a place on the guide route where the uphill slope r is greater than the threshold value β (step S9). The threshold value β is, for example, 8%. The threshold value β is an example of a slope threshold. Here, the threshold values ​​α and β in steps S8 and S9 are respectively set to the traction weight and the uphill slope that are predicted to limit the output of FC4 due to the temperature rise of FC4 when the fuel cell vehicle 1 is towing the towed vehicle on the guide route. For example, the threshold values ​​α and β are set based on experimental results. The processing of steps S8 and S9 is an example of the processing performed by the prediction unit that predicts whether the output of FC4 is limited by the output limiting unit when the guide route is being traveled. In the case of no in step S9, the processing of step S10 is executed and the control ends. In addition, the order of steps S8 and S9 is arbitrary.

[0062] If the answer is yes in step S9, the ECU 3 executes a warning process (step S11). The warning process is a process for notifying the driver of the possibility of a reduction in vehicle speed. As described above, the possibility of a reduction in vehicle speed due to the limitation of the output of FC4 can be predicted with high accuracy based on the traction weight f and the uphill slope r on the guidance route. When a reduction in vehicle speed is predicted, the situation can be reported to the driver in advance. The specific contents of the warning process are described in detail below.

[0063] [Warning handling]

[0064] like Figure 4As shown, during the warning process, the ECU 3 causes the dashboard display 9 to display an image D2 (step S21). Image D2 is an image that notifies the driver of the possibility of a reduction in vehicle speed on a slope and urges the driver to determine whether to change the guide route currently set in the navigation device 60. For example, the message "There is a possibility of a reduction in vehicle speed on a slope. Change the guide route?" and "Yes", "No" and "Cancel" are displayed in image D2. In this way, since the driver can be aware of the possibility of a reduction in vehicle speed in advance, the driver's sense of disharmony and uneasiness can be reduced even when the vehicle speed actually decreases. The processing of step S21 is an example of the processing performed by the control unit. Image D2 is an example of a warning of a situation in which there is a possibility that the fuel cell vehicle 1 will reduce its speed when traveling on a predetermined route in a towing driving state, and is also an example of a warning urging the driver to change the predetermined route set in the navigation device 60.

[0065] Next, ECU3 determines whether there is an instruction to change the guidance route (step S22). If step S22 is negative, that is, if the "No" or "Cancel" area of ​​image D2 is operated, ECU3 causes the instrument panel display 9 to display image D5 (step S29), and ends this control.

[0066] If the answer is YES in step S22 , that is, if the “YES” area of ​​the image D2 is operated, the ECU 3 outputs an instruction to the navigation device 60 to search again for a new guidance route that does not include a point with a slope r greater than or equal to the threshold β (step S23 ).

[0067] Next, the ECU 3 determines whether the navigation device 60 has found the guide route by communicating with the navigation device 60 (step S24). In the case of no in step S24, the ECU 3 causes the dashboard display 9 to display an image D3 notifying the driver that a new guide route cannot be found (step S25). For example, the message "Guide route cannot be found" is displayed on the image D3. Then, the ECU 3 executes the processing of step S29, and the control ends.

[0068] If the answer is yes in step S24, the ECU 3 causes the dashboard display 9 to display an image D4 urging the driver to change to a new guidance route (step S26). For example, the image D4 displays a message "A new guidance route has been retrieved. Please touch the guidance route you want to change." and "Cancel". The processing of step S26 is an example of the processing performed by the control unit. Figure 6 This is a diagram showing an example of an image displayed on the navigation display 61 when a new guidance route is found. Figure 6The already set guidance route R1 and the newly searched guidance routes R2 and R3 are displayed. The driver can change the guidance route by touching either of the guidance routes R2 and R3.

[0069] Next, the ECU 3 determines whether the “cancel” area of ​​the image D4 has been operated (step S27 ). If the answer is yes in step S27 , the ECU 3 executes the process of step S29 , and the present control ends.

[0070] If the answer is No in step S27, ECU3 determines whether the guidance route has been changed based on the signal from the navigation device 60 (step S28). If the answer is No in step S28, the process of step S27 is executed again. If the answer is Yes in step S28, ECU3 executes the process of step S29, and the control ends.

[0071] [Variation of warning processing]

[0072] Next, a plurality of modified examples of the warning process will be described. Fig. 7A This is a flowchart showing a first modified example of the warning process. Figure 7B This is a flowchart showing a second modified example of the warning process. Fig. 8A as well as Figure 8B These are examples of images D6 and D7 displayed on the instrument panel display 9. When the images D6 and D7 are displayed on the instrument panel display 9, messages in the images may be outputted by sound from a speaker in the vehicle cabin of the fuel cell vehicle 1.

[0073] First, the first variant of the warning process is described. Fig. 7AAs shown, the ECU3 determines whether the towing weight f is greater than the threshold value α1 (step S31). The threshold value α1 is a value greater than the above-mentioned threshold value α by a predetermined value. The threshold value α1 is, for example, 3000 kg. The threshold value α1 is an example of a weight threshold. In the case of yes in step S31, that is, when the towing weight f is relatively heavy, the ECU3 causes the instrument panel display 9 to display image D6 (step S32). In the case of no in step S31, that is, when the towing weight f is greater than the threshold value α but less than the threshold value α1, the ECU3 causes the instrument panel display 9 to display image D7 (step S33). In image D6, compared with image D7, the possibility of a reduction in vehicle speed is emphasized and the avoidance of driving on the guide route is also emphasized. For example, in image D6, a message "There is a possibility of a significant reduction in vehicle speed on a slope. Please try to avoid driving on the guide route." is displayed. For example, in image D7, a message "There is a possibility of a reduction in vehicle speed on a slope. It is recommended to avoid driving on the guide route." is displayed. In this way, the warning may be issued more emphatically as the towing weight f is larger, without prompting the driver to change the guidance route already set in the navigation device 60. The processing of step S32 is an example of processing executed by the control unit. Images D6 and D7 are an example of a warning that there is a possibility that the fuel cell vehicle 1 will reduce its speed when the fuel cell vehicle 1 is traveling on the planned driving route in the towing driving state, and are also an example of a warning that prompts the driver to avoid the planned driving route.

[0074] Next, a second variant of the warning process is described. Figure 7B As shown, ECU3 determines whether there is a place where the slope r is greater than the threshold value β1 on the guidance route already set in the navigation device 60 (step S31a). The threshold value β1 is a value greater than the above-mentioned threshold value β by a specified value. The threshold value β1 is an example of a slope threshold. The threshold value β1 is, for example, 12%. In the case of yes in step S31a, that is, when there is a place with a relatively steep uphill slope on the guidance route, ECU3 executes the processing of step S32. In the case of no in step S31a, that is, when the uphill slope r is greater than the threshold value β but less than the threshold value β1, ECU3 executes the processing of step S33. In this way, the guidance route already set in the navigation device 60 can be changed without being urged, but the steeper the uphill slope on the guidance route, the more emphasized the warning.

[0075] [Calculation process of traction weight f]

[0076] Next, the calculation process of the towing weight f will be described. Fig. 9It is a flowchart showing an example of the calculation process of the traction weight f. The ECU 3 determines whether the fuel cell vehicle 1 is in the forward travel driven by the motor 50 (step S41). This is because when the motor 50 is stopped or the motor 50 is in the regenerative operation state, the traction travel state information for calculating the traction weight f described later cannot be obtained. Here, the regenerative operation refers to the operation of operating the motor 50 as a generator when the fuel cell vehicle 1 is decelerating or going downhill to obtain the braking force of the fuel cell vehicle 1 and charging at least a part of the generated regenerative power to BAT8. Among them, the processing of step S41 is specifically based on the vehicle speed indicated by the vehicle speed sensor and the power consumption of the motor 50 to determine whether the fuel cell vehicle 1 is in the forward travel driven by the motor 50. If the vehicle speed indicated by the vehicle speed sensor is a value greater than zero and the power consumption of the motor 50 is a value greater than zero, it is determined that the fuel cell vehicle 1 is in the forward travel driven by the motor 50. The power consumption of the motor 50 can be calculated based on the driving current and rotation speed of the motor 50. In the case of no in step S41, this control is terminated.

[0077] If the answer is yes in step S41, the ECU 3 obtains the towing driving state information (step S42). The towing driving state information includes the inclination angle of the road surface on which the fuel cell vehicle 1 is traveling in the towing driving state in which the fuel cell vehicle 1 is towing the towed vehicle 100, the torque of the motor 50 when the fuel cell vehicle 1 is traveling on the road surface at the inclination angle in the towing driving state, and the vehicle speed of the fuel cell vehicle 1. The inclination angle [rad] of the road surface can be obtained from the inclination angle sensor of the fuel cell vehicle 1. The torque [N] of the motor 50 can be calculated, for example, by dividing the power consumption [W] of the motor 50 by the rotation speed [r / min] of the motor 50 and multiplying it by a predetermined coefficient. As described above, the power consumption of the motor 50 can be calculated based on the driving current and rotation speed of the motor 50. The driving current of the motor 50 can be obtained from the current sensor installed on the motor 50. The rotation speed of the motor 50 can be obtained by the rotation speed sensor provided on the motor 50. The vehicle speed [km / h] can be obtained from the vehicle speed sensor of the fuel cell vehicle 1. The processing of step S42 is an example of the processing performed by the information acquisition unit.

[0078] Next, the ECU 3 refers to the map and calculates the towing weight f based on the towing running state information (step S43 ). Fig.10 This is a diagram showing an example of a plurality of maps that define the torque of the motor 50, the vehicle speed, and the traction weight f for each inclination angle θ1, θ2, θ3, etc. of the road surface. These maps are pre-stored in the memory of the ECU 3. The memory of the ECU 3 is an example of a storage unit. The inclination angles θ1, θ2, θ3, etc. include both the case of an uphill slope and the case of a downhill slope. Fig.10In the map shown, the inclination angle θ1 represents the case of an uphill slope.

[0079] Torque contour lines T1 to T3 are shown in each map. Among the torque contour lines T1 to T3, torque contour line T1 indicates the maximum torque, and torque contour line T3 indicates the minimum torque. The inclination angle includes not only the uphill slope but also the downhill slope. For the map with the inclination angle being the uphill slope, the larger the torque of the motor 50, the slower the vehicle speed, and the smaller the inclination angle at the uphill slope, the larger the towing weight f is set. This is because there is a tendency that the larger the towing weight f, the larger the torque of the motor 50 required to tow the towed vehicle 100. In addition, there is a tendency that the vehicle speed decreases as the towing weight f increases. In addition, under the same conditions of the torque of the motor 50 and the vehicle speed, the smaller the inclination angle at the uphill slope, the larger the towing weight f is. In addition, the same is true for the map with the inclination angle being the gentle downhill slope. The larger the torque of the motor 50, the slower the vehicle speed, and the smaller the inclination angle at the downhill slope, the larger the towing weight f is set. In a downhill slope with a gentle inclination angle, the effect of gravity on acceleration is small and the rolling resistance is large, so it is the same as the case of an uphill slope. For the mapping of a downhill slope with a steep inclination angle, the smaller the torque of the motor 50, the faster the vehicle speed, and the smaller the inclination angle of the downhill slope, the larger the towing weight f is set. This is because in this case, the acceleration caused by the gravity becomes large and the rolling resistance becomes small, so the towed vehicle 100 can be towed even if the torque of the motor 50 is small. By using such a map to calculate the towing weight f, the processing load of the ECU 3 can be reduced.

[0080] [Modification of Calculation Process of Towing Weight f]

[0081] Alternatively, the towing weight f may be calculated using the following calculation formula (1).

[0082] f={(T×Gr÷D-Ra) / (g(μ+sinθ)+a)}-F…(1)

[0083] The calculation formula (1) is stored in the memory of ECU3. θ[rad] represents the inclination angle of the road surface on which the fuel cell vehicle 1 is traveling at the current moment. As described above, the inclination angle of the road surface can be obtained from the inclination angle sensor of the fuel cell vehicle 1. T[N·m] represents the torque of the motor 50 when the fuel cell vehicle 1 is traveling on the road surface at the inclination angle in the towing driving state. Gr[-] represents the speed ratio of the transmission 52 when the fuel cell vehicle 1 is traveling on the road surface at the inclination angle in the towing driving state. If the speed ratio of the transmission 52 is fixed, the speed ratio is always pre-stored in the memory of ECU3 as a constant value. If the transmission 52 is a multi-speed transmission that can be switched to multiple speed ratios, the speed ratio is detected from a sensor or the like. D[m] is the outer diameter of the wheel 55, which is pre-stored in the memory of ECU3 as an inherent value of the fuel cell vehicle 1. Ra[N] represents the air resistance of the fuel cell vehicle 1 when the fuel cell vehicle 1 is traveling on the road surface at the inclination angle in the towing driving state. The higher the vehicle speed, the more the air resistance increases exponentially. A map defining the relationship between air resistance and vehicle speed is stored in the memory of the ECU 3 , and the air resistance can be calculated from the current vehicle speed with reference to the map.

[0084] g[m / s 2 ] is the gravitational acceleration, which is pre-stored in the memory of the ECU 3. μ[-] represents the rolling resistance coefficient, which is pre-stored in the memory of the ECU 3 as a unique value of the fuel cell vehicle 1. a[m / s 2 ] represents the acceleration of the fuel cell vehicle 1 when the fuel cell vehicle 1 is traveling on the road with the inclined angle in the towing driving state. The acceleration can be detected by the acceleration sensor mounted on the fuel cell vehicle 1. F[kg] represents the weight of the fuel cell vehicle 1 and is pre-stored in the memory of the ECU 3 as an inherent value of the fuel cell vehicle 1. In this way, by using the calculation formula, the towing weight f can be calculated with high accuracy.

[0085] [other]

[0086] Although the instrument panel display 9 is used as the reporting unit to display the images D1 to D7, it is not limited to this. For example, the warning may be reported by using the navigation display 61 as the reporting unit to display the images D1 to D7. In addition, a speaker provided in the vehicle compartment or a speaker provided in the navigation device 60 may be used as the reporting unit, and the message displayed in the images D1 to D7 may be outputted by the speaker to thereby report the warning. The warning may also be reported only by the image display or the sound output. In addition, the warning may also be reported by displaying a predetermined symbol, graphic, mark, etc. on the instrument panel display 9 or the like. In addition, a lighting device such as an LED provided in the vehicle compartment may be used as the reporting unit, and the lighting device may be lit, or the lighting device may be flashed, etc., to thereby report the above-mentioned warning. In addition, the above-mentioned warning may also be reported by means of a buzzer through a speaker. In addition, in the case of emphasizing the reporting of the warning, the symbol displayed on the instrument panel display 9 or the like may be enlarged or flashed, the buzzer may be increased, or the type of buzzer may be changed, or the lighting pattern of the LED may be changed.

[0087] Although the traction weight f is calculated as in steps S1 and S2 and a determination is made as to whether the fuel cell vehicle 1 is towing the towed vehicle based on the size of the traction weight f, this is not limiting. For example, in a case where the fuel cell vehicle 1 is equipped with a camera for photographing the rear of the fuel cell vehicle 1, it is possible to determine whether the fuel cell vehicle 1 is towing the towed vehicle by performing image recognition processing on the image photographed by the camera. In addition, a sensor for detecting the engagement of the hook ball 2b with the connector 108 may be provided on the hook 2a around the hook ball 2b, and the sensor may be used to determine whether the fuel cell vehicle 1 is towing the towed vehicle. In either case, the traction weight f needs to be calculated independently of the determination as to whether the fuel cell vehicle 1 is towing the towed vehicle.

[0088] The above threshold values ​​α, α1, β, and β1 are fixed values, but are not limited thereto. For example, the larger the traction weight f, the smaller the threshold value β and β1. This is because the larger the traction weight f, the larger the output of FC4 and the higher the temperature even if the uphill slope is small, and there is a possibility that the output of FC4 is limited. In addition, the lower the outside air temperature, the larger the threshold value α, α1, β, and β1. This is because the lower the outside air temperature, the more the heat dissipation of the cooling water in the radiator 43 can be promoted to suppress the temperature increase of FC4, and the possibility that the output of FC4 is limited is reduced.

[0089] The ECU 3 can highlight a point where the uphill gradient is equal to or greater than the threshold value α or α1 by causing the navigation display 61 to flash, for example, so that the driver can easily avoid the point.

[0090] The ECU 3 may display the calculated towing weight f on the instrument panel display 9 or the like.

[0091] The fuel cell vehicle 1 is a passenger car, and may be any of a large passenger car, a medium passenger car, or a small passenger car. In addition, if the fuel cell vehicle is not provided with a sensor for directly detecting the towing weight, it may be a vehicle other than a passenger car.

[0092] As mentioned above, although the embodiment of the present invention is described in detail, the present invention is not limited to the above-mentioned specific embodiment, and various deformation|transformation and changes are possible within the scope of the summary of the present invention described in the claims.

Claims

1. A control device for a fuel cell vehicle, which is a control device for a fuel cell vehicle using a fuel cell as a power source and a motor as a driving source, It is characterized in that include: an output limiting unit configured to limit the output of the fuel cell when a temperature-related value related to the temperature of the fuel cell indicates that the temperature is equal to or greater than a temperature threshold; a calculation unit configured to calculate a weight of a towed vehicle towed by the fuel cell vehicle; a slope acquisition unit configured to acquire an uphill slope at each point in a planned travel route of the fuel cell vehicle; a prediction unit configured to predict, based on the weight of the towed vehicle and the uphill slope, whether the output of the fuel cell is limited by the output limiting unit when the fuel cell vehicle travels along the scheduled travel route in a towing travel state in which the fuel cell vehicle tows the towed vehicle; as well as a control unit configured to, when the prediction unit predicts that the output of the fuel cell is limited, issue a warning, through a reporting unit mounted on the fuel cell vehicle, that there is a possibility that the vehicle speed of the fuel cell vehicle will decrease when the fuel cell vehicle is traveling on the scheduled driving route in the towing driving state; The vehicle further includes an information acquisition unit configured to acquire traction driving state information, the traction driving state information including an inclination angle of a road surface on which the fuel cell vehicle is traveling in the traction driving state, and a torque of the motor when the fuel cell vehicle is traveling on the road surface at the inclination angle in the traction driving state. The calculation unit is configured to calculate the weight of the towed vehicle based on the towing driving state information. The towing running state information includes the weight of the fuel cell vehicle, the air resistance of the fuel cell vehicle when the fuel cell vehicle is running on the road surface at the inclined angle in the towing running state, the acceleration of the fuel cell vehicle, and the gear ratio of the transmission of the fuel cell vehicle.

2. The control device for a fuel cell vehicle according to claim 1, It is characterized in that The prediction unit is configured to predict that the output of the fuel cell is limited when the weight of the towed vehicle is equal to or greater than a weight threshold and when at least one of the uphill gradients at each point is equal to or greater than a gradient threshold.

3. The control device for a fuel cell vehicle according to claim 1, It is characterized in that The towing running state information includes the vehicle speed of the fuel cell vehicle when the fuel cell vehicle is running on the road surface at the inclined angle in the towing running state.

4. The control device for a fuel cell vehicle according to claim 3, It is characterized in that The apparatus further includes a storage unit storing a map defining a relationship among the torque, the tilt angle, the vehicle speed, and the weight of the towed vehicle. The calculation unit is configured to calculate the weight of the towed vehicle by referring to the map.

5. The control device for a fuel cell vehicle according to claim 1, It is characterized in that The vehicle further includes a storage unit storing a calculation formula that defines a relationship among the torque, the tilt angle, the weight of the fuel cell vehicle, the air resistance, the acceleration, the speed ratio, and the weight of the towed vehicle. Here, the calculation unit is configured to calculate the weight of the towed vehicle based on the calculation formula.

6. The control device for a fuel cell vehicle according to any one of claims 1 to 5, It is characterized in that The control unit is configured to issue a warning urging travel to avoid the planned travel route through the reporting unit.

7. The control device for a fuel cell vehicle according to any one of claims 1 to 5, It is characterized in that The control unit is configured to make the announcing unit announcing a warning more emphatically as the weight of the towed vehicle increases.

8. The control device for a fuel cell vehicle according to any one of claims 1 to 5, It is characterized in that The control unit is configured to more emphatically issue a warning via the notification unit as the upward slope gradient increases.

9. The control device for a fuel cell vehicle according to any one of claims 1 to 5, It is characterized in that The gradient acquisition unit is configured to acquire the uphill gradient from a navigation device in which the planned travel route is set.

10. The control device for a fuel cell vehicle according to claim 9, It is characterized in that The control unit is configured to, when the prediction unit predicts that the output of the fuel cell is limited, cause the notification unit to notify a warning urging a change in the planned travel route set in the navigation device.

11. The control device for a fuel cell vehicle according to any one of claims 1 to 5, It is characterized in that The fuel cell vehicle is a passenger car.

12. A fuel cell vehicle, It is characterized in that include: A fuel cell, a motor, and a control device for a fuel cell vehicle according to any one of claims 1 to 11.

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