Vehicle control device, vehicle, and control method

Abstract

A vehicle control device includes a water immersion state detection unit (104), which detects the water immersion state in the exhaust pipe (30) based on a first exhaust temperature measured at a first location on the upstream side of the exhaust pipe (30) of the engine (10), a second exhaust temperature measured at a second location on the downstream side of the exhaust pipe (30) of the engine (10), and the exhaust pressure in the exhaust pipe (30) of the engine (10). The water immersion state detection unit (104) determines that water has penetrated into the exhaust pipe (30) when the increase in exhaust pressure per unit time is greater than a first threshold value and the decrease in the second exhaust temperature relative to the first exhaust temperature per unit time is greater than a second threshold value.

Description

Technical Field

[0001] The present invention relates to a vehicle control device, a vehicle and a control method. Background Art

[0002] A vehicle including an internal combustion engine (hereinafter referred to as “engine”) is known (for example, refer to Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2007-270646 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] Vehicles are used in a variety of environments, and sometimes they have to be driven in a situation where the road is flooded and the vehicle is submerged due to heavy rain or the like. When the vehicle is driven in such a situation, water may enter the exhaust pipe of the engine, causing an unusual increase in the pressure on the exhaust side, which may cause the engine to stop (engine stall). In addition, water entering the exhaust pipe may also cause a malfunction of the exhaust purification device in the exhaust pipe.

[0008] Under this background, there is a demand for early detection of a flooded state in an exhaust pipe of an engine in a vehicle. In addition, when a flooded state in an exhaust pipe of an engine occurs, it is required to reduce the risk of stopping the engine and prevent the vehicle from being unable to drive itself.

[0009] The present invention is made in view of the above-mentioned problems, and its purpose is to provide a vehicle control device and a control method, according to which the vehicle control device and the control method can detect the flooding state of the exhaust pipe in the engine at an early stage. In addition, on the other hand, the present invention aims to provide a vehicle control device, a vehicle and a control method, according to which the engine stop can be suppressed when the flooding state in the exhaust pipe of the engine occurs.

[0010] Solutions to the problem

[0011] As a main content of the present invention to solve the above-mentioned problems, a control device in one embodiment is a control device for a vehicle having an internal combustion engine, including:

[0012] a first exhaust gas temperature information acquisition unit that acquires information related to a first exhaust gas temperature measured at a first location on an upstream side in the exhaust pipe of the internal combustion engine;

[0013] a second exhaust gas temperature information acquiring unit that acquires information related to a second exhaust gas temperature measured at a second location on the downstream side in the exhaust pipe;

[0014] an exhaust pressure information acquisition unit that acquires information related to the exhaust pressure measured in the exhaust pipe; and

[0015] a water intrusion state detecting unit for detecting a water intrusion state in the exhaust pipe based on the first exhaust temperature, the second exhaust temperature, and the exhaust pressure;

[0016] The water immersion state detection unit determines that the water immersion state has occurred when an increase in the exhaust pressure per unit time is equal to or greater than a first threshold and an decrease in the second exhaust temperature relative to the first exhaust temperature per unit time is equal to or greater than a second threshold.

[0017] In addition, another embodiment is a vehicle including the above-mentioned control device.

[0018] In addition, another embodiment is a control method for a vehicle having an internal combustion engine, comprising:

[0019] A first process of acquiring information related to a first exhaust gas temperature measured at a first location on an upstream side in an exhaust pipe of the internal combustion engine;

[0020] a second process of acquiring information related to a second exhaust gas temperature measured at a second location on the downstream side in the exhaust pipe;

[0021] a third process of acquiring information related to the exhaust pressure measured in the exhaust pipe; and

[0022] a fourth process of detecting a water intrusion state in the exhaust pipe based on the first exhaust temperature, the second exhaust temperature, and the exhaust pressure;

[0023] In the fourth process, it is determined that the immersion state has occurred when the increase amount of the exhaust pressure per unit time is equal to or greater than a first threshold and the decrease amount of the second exhaust temperature relative to the first exhaust temperature per unit time is equal to or greater than a second threshold.

[0024] Effects of the Invention

[0025] According to the vehicle control device of the present invention, it is possible to detect the water flooding state in the exhaust pipe of the engine at an early stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a diagram showing an example of the structure of a vehicle according to an embodiment.

[0027] Figure 2This is a diagram showing the temporal changes in the upstream exhaust temperature and the downstream exhaust temperature when water enters the exhaust pipe of the engine while the vehicle is running.

[0028] Figure 3 This is a diagram showing a change over time in the exhaust pressure when water enters the exhaust pipe of the engine while the vehicle is running.

[0029] Figure 4 This is a diagram showing an example of an operation flow of the ECU according to one embodiment. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that in this specification and the drawings, components having substantially the same functions are denoted by the same reference numerals and repeated descriptions are omitted.

[0031] [Vehicle structure]

[0032] Below, refer to Figure 1 A configuration of a vehicle according to an embodiment will be described. In this embodiment, a mode in which a vehicle control device according to the present invention is applied to a diesel engine vehicle will be described.

[0033] Figure 1 2 is a diagram showing a configuration of a vehicle U according to the present embodiment.

[0034] The vehicle U of this embodiment includes: an engine 10, a transmission 12, an intake pipe 20, an air filter 21, a turbocharger 22, an intake throttle valve 23, an exhaust pipe 30, an EGR (Exhaust Gas Recirculation) device 31, an exhaust brake valve 32, an exhaust purification device 40, various sensors 51~53 and an ECU (Electronic Control Unit) 100, etc.

[0035] The engine 10 is configured to include a combustion chamber and a fuel injection device (not shown) for supplying fuel to the combustion chamber. The engine 10 generates power by burning and expanding a mixture of fuel and air in the combustion chamber. The engine 10 is connected to an intake pipe 20 for introducing air into the combustion chamber and an exhaust pipe 30 for discharging the exhaust gas after combustion discharged from the combustion chamber to the outside of the vehicle. In addition, a crankshaft as an output shaft of the engine 10 is connected to a transmission 12 through a torque converter.

[0036] The operation of the engine 10 is controlled by a control signal from the ECU 100. That is, the engine 10 causes the fuel injection device to inject fuel according to the fuel injection amount and fuel injection timing determined by the control signal from the ECU 100.

[0037] The transmission 12 changes the speed of the rotational motion input from the engine 10 and transmits it to the drive wheel (not shown). The transmission 12 is, for example, a step-type transmission, and is configured to include a plurality of hydraulic friction engagement elements and a planetary gear device. By selectively engaging the plurality of friction engagement elements, a plurality of gears (shift gears) can be selectively achieved. It should be noted that the operation of the transmission 12 can be controlled by a control signal from the ECU 100.

[0038] The intake pipe 20 is a flow path that sucks fresh air (air) from the intake port 20a and supplies the fresh air to the engine 10. In the intake pipe 20, an air filter 21, a compressor of a turbocharger 22, and an intake throttle valve 23 are provided in order from the intake port 20a on the upstream side to the combustion chamber of the engine 10.

[0039] The air cleaner 21 is supplied with air sucked from the air intake port 20 a , removes impurities from the air, and then sends the air to the turbocharger 22 side.

[0040] The turbocharger 22 rotates a turbine using the pressure of the exhaust gas in the exhaust pipe 30 , and the rotation of the turbine activates a coaxial compressor to compress the air flowing through the intake pipe 20 and deliver it to the engine 10 side.

[0041] The intake throttle valve 23 adjusts the amount of air flowing through the intake pipe 20 from the intake port 20a to the combustion chamber of the engine 10. The intake throttle valve 23 is, for example, a butterfly-shaped electromagnetic valve provided in the intake pipe 20, and adjusts the degree of opening of the intake passage formed by the intake pipe 20 by a control signal from the ECU 100.

[0042] The exhaust pipe 30 is a flow path for discharging the exhaust gas after combustion from the engine 10 to the outside of the vehicle U. In the exhaust pipe 30 , an EGR device 31 , a turbine of the turbocharger 22 , and an exhaust purification device 40 are provided in this order from the engine 10 to the downstream side.

[0043] The EGR device 31 allows a portion of the exhaust gas flowing in the exhaust pipe 30 to circulate in the intake pipe 20. The EGR device 31 is configured to include: an EGR passage that connects the exhaust pipe 30 with the intake pipe 20 and allows a portion of the exhaust gas discharged from the combustion chamber 11 to the exhaust pipe 30 to flow to one side of the intake pipe 20; an EGR cooler that cools the exhaust gas flowing in the EGR passage; and an EGR valve that adjusts the flow rate of the exhaust gas flowing in the EGR passage.

[0044] The exhaust brake valve 32 blocks the exhaust passage formed by the exhaust pipe 30 as needed to apply braking force to the vehicle. The exhaust brake valve 32 is, for example, a butterfly-shaped solenoid valve disposed in the exhaust pipe 30 and adjusts the degree of opening of the exhaust passage formed by the exhaust pipe 30 by a control signal from the ECU 100.

[0045] The exhaust purification device 40 includes an oxidation catalyst 41, a PM (Particulate Matter) filter 42, an SCR (Selective Catalytic Reduction) catalyst 43, and a urea water injection device 43a. The oxidation catalyst 41, the PM filter 42, and the SCR catalyst 43 are arranged in the exhaust pipe 30 in this order from the upstream side to the downstream side.

[0046] The oxidation catalyst 41 oxidizes and removes HC and CO contained in the exhaust gas. For example, the oxidation catalyst 41 is formed by supporting an oxidation catalyst such as platinum or cerium oxide on a carrier such as cordierite or silicon carbide.

[0047] The oxidation catalyst 41 is disposed adjacent to the PM filter 42 on the upstream side of the PM filter 42 in the exhaust pipe 30. When the PM filter 42 is regenerated, the oxidation catalyst 41 also functions to oxidize HC exhausted from the engine 10 and increase the exhaust temperature by the oxidation heat.

[0048] The PM filter 42 captures PM (Particulate Matter) contained in the exhaust gas. The PM filter 42 has, for example, a structure in which a plurality of honeycomb-shaped flow paths are formed by a collection wall formed of porous ceramics (e.g., porous ceramics of cordierite or silicon carbide), and an inlet and an outlet are alternately blocked so that the exhaust gas passes through the collection wall.

[0049] The SCR catalyst 43 adsorbs ammonia generated by hydrolysis of urea water injected from an injection nozzle of a urea water injection device 43 a disposed at an upstream side thereof, and selectively reduces and purifies NOx from the exhaust gas using the adsorbed ammonia.

[0050] The various sensors 51 to 53 are provided to detect the state of each part of the vehicle U. Here, in order to detect the state of the exhaust gas discharged from the engine 10, a first temperature sensor 51, a second temperature sensor 52, and a pressure sensor 53 are provided as the various sensors 51 to 53.

[0051] The first temperature sensor 51 is disposed at a location on the upstream side of the exhaust pipe 30 (a location further upstream than the exhaust purification device 40, the same below) to detect the temperature of the exhaust gas flowing at the location. It should be noted that the first temperature sensor 51 of the present embodiment is disposed at a location of the exhaust manifold of the exhaust pipe 30.

[0052] The second temperature sensor 52 is disposed at a location on the downstream side of the exhaust pipe 30 (a location further downstream than the exhaust purification device 40, the same below) to detect the temperature of the exhaust gas flowing at the location. It should be noted that the second temperature sensor 52 of the present embodiment is disposed at a location near the outlet of the exhaust pipe 30.

[0053] The pressure sensor 53 detects the exhaust pressure of the exhaust gas flowing through the exhaust pipe 30. In addition, the pressure sensor 53 of the present embodiment is disposed at a location of the exhaust manifold of the exhaust pipe 30.

[0054] These various sensors 51 to 53 sequentially transmit information obtained by detection as detection signals to the ECU 100. In addition, these various sensors 51 to 53 can be realized by using well-known sensors.

[0055] ECU100 (equivalent to the "control device" of the present invention) performs overall control of the actions of various parts of the vehicle U. ECU100 is configured to include, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input port, and an output port. For example, the various functions of ECU100 described later are realized by the CPU referring to the control program and various data stored in the ROM, RAM, etc. However, this function is not limited to being realized by processing performed by software, and of course it can also be realized by a dedicated hardware circuit.

[0056] It should be noted that the ECU 100 controls the components of the vehicle U, such as the engine 10, or receives data from the components. In addition, the ECU 100 acquires sensor information from various sensors (such as the first temperature sensor 51, the second temperature sensor 52, and the pressure sensor 53) provided in the vehicle U to detect the states of the exhaust gas purification device 40 and the components of the vehicle U.

[0057] [ECU structure]

[0058] Next, refer to Figure 1 to Figure 4 , an example of the structure of ECU 100 according to the present embodiment is described.

[0059] The ECU 100 includes a first exhaust temperature information acquisition unit 101 , a second exhaust temperature information acquisition unit 102 , an exhaust pressure information acquisition unit 103 , a flooded state detection unit 104 , a vehicle control unit 105 , and a notification unit 106 .

[0060] The first exhaust temperature information acquisition unit 101 acquires information related to the exhaust temperature measured at a location on the upstream side in the exhaust pipe 30 of the engine 10 (hereinafter referred to as "upstream exhaust temperature"). In the present embodiment, the first exhaust temperature information acquisition unit 101 acquires information related to the upstream exhaust temperature from a first temperature sensor 51 provided in the exhaust manifold of the exhaust pipe 30.

[0061] The second exhaust gas temperature information acquisition unit 102 acquires information related to the exhaust gas temperature measured at a location on the downstream side in the exhaust pipe 30 of the engine 10 (hereinafter referred to as "downstream exhaust gas temperature"). In the present embodiment, the second exhaust gas temperature information acquisition unit 102 acquires information related to the downstream exhaust gas temperature from a second temperature sensor 52 disposed at a location near the outlet of the exhaust pipe 30.

[0062] The exhaust pressure information acquisition unit 103 acquires information on the exhaust pressure measured in the exhaust pipe 30 of the engine 10. In the present embodiment, the exhaust pressure information acquisition unit 103 acquires information on the exhaust pressure from the pressure sensor 53 disposed in the exhaust pipe 30.

[0063] The water immersion state detection unit 104 detects the water immersion state in the exhaust pipe 30 of the engine 10 based on the information related to the upstream exhaust temperature obtained by the first exhaust temperature information acquisition unit 101, the information related to the downstream exhaust temperature obtained by the second exhaust temperature information acquisition unit 102, and the information related to the exhaust pressure obtained by the exhaust pressure information acquisition unit 103.

[0064] Specifically, the water immersion state detection unit 104 determines that water has penetrated into the exhaust pipe 30 of the engine 10 when the increase in exhaust pressure per unit time is greater than a first threshold value and the decrease in downstream exhaust temperature relative to upstream exhaust temperature per unit time is greater than a second threshold value; when this condition is not met, it is determined that no water has penetrated into the exhaust pipe 30 of the engine 10.

[0065] Figure 2 1 is a diagram showing the temporal changes of the upstream exhaust gas temperature and the downstream exhaust gas temperature when water intrudes into the exhaust pipe 30 of the engine 10 while the vehicle U is traveling. Figure 3 1 is a diagram showing the change over time of the exhaust pressure when water enters the exhaust pipe 30 of the engine 10 while the vehicle U is traveling. Figure 2 , Figure 3 2 shows a situation where water intrudes into the exhaust pipe 30 at time T1.

[0066] When the vehicle U is running, the exhaust temperature changes slowly in a normal state (a steady-state operation state in which no water is immersed in the exhaust pipe 30. The same applies below) according to the operation state of the engine 10. Moreover, the temperature difference between the upstream exhaust temperature and the downstream exhaust temperature usually depends mainly on the heat dissipation in the exhaust purification device 40 and the exhaust pipe 30 during the period from when the exhaust gas discharged from the engine 10 reaches the downstream position. In a normal state, for example, the upstream exhaust temperature is about 500°C and the downstream exhaust temperature is about 300°C. In addition, when the vehicle U is running, the exhaust pressure usually changes slowly in accordance with the change in the engine load.

[0067] In this regard, when water enters the exhaust pipe 30 ( Figure 2 At the time T1, the temperature on the downstream side of the exhaust pipe 30 drops rapidly due to the influence of the surrounding water. Shortly after the water enters the exhaust pipe 30, the water has not yet reached the upstream side of the exhaust pipe 30, so the exhaust temperature on the upstream side of the exhaust pipe 30 is kept at a substantially constant temperature. In addition, at this time, a part of the exhaust passage in the exhaust pipe 30 is blocked by water, so the exhaust pressure rises sharply.

[0068] Thus, by focusing on the exhaust temperature and the exhaust pressure, it is possible to detect the intrusion of water into the exhaust pipe 30. However, if it is determined whether the intrusion of water into the exhaust pipe 30 has occurred based only on the change in the exhaust pressure, the ECU 100 may erroneously determine that water has intruded into the exhaust pipe 30 when the exhaust brake valve 32 is actuated. In addition, if it is determined whether the intrusion of water into the exhaust pipe 30 has occurred based only on the change in the exhaust temperature, the ECU 100 may erroneously determine that water has intruded into the exhaust pipe 30 when ice and snow are attached to the periphery of the exhaust pipe 30. In addition, when the turbocharger 22 is actuated or when the filter regeneration control of the PM filter 42 is performed, the exhaust temperature and the exhaust pressure also vary greatly. Therefore, if only one of the exhaust temperature or the exhaust pressure is focused on, an erroneous determination may be made by the ECU 100.

[0069] From this point of view, the flooding state detection unit 104 determines that water has entered the exhaust pipe 30 only when the following two conditions are simultaneously satisfied: a first condition of whether the amount of increase in the exhaust pressure per unit time is greater than a first threshold value and a second condition of whether the amount of decrease in the downstream exhaust temperature relative to the upstream exhaust temperature per unit time is greater than a second threshold value. For example, the flooding state detection unit 104 determines that water has entered the exhaust pipe 30 only when the amount of increase in the exhaust pressure during a period of 1 second is greater than 2 to 4 times the exhaust pressure immediately before, and the amount of decrease in the downstream exhaust temperature relative to the upstream exhaust temperature during a period of 10 seconds is greater than 100° C. to 300° C.

[0070] Here, the reason why the water flooding state detection unit 104 observes the time change amount per unit time is to detect the water flooding state in the exhaust pipe 30 at an early stage and to ensure the detection accuracy.

[0071] It should be noted that, preferably, once the flooded state detection unit 104 determines that water has entered the exhaust pipe 30 in the above-mentioned determination process, the mark indicating the flooded state is not removed for a period of time even if the above-mentioned conditions are no longer satisfied. Specifically, preferably, the flooded state detection unit 104 does not remove the mark indicating the flooded state for a period of time from when the switch is turned off during the current driving to when the switch is turned on during the next driving, or for a period of time (for example, several minutes) from when the above-mentioned conditions are no longer satisfied, even if the above-mentioned conditions are no longer satisfied. This is because the situation in which water enters the exhaust pipe 30 depends on the conditions of the road itself on which the vehicle U is traveling.

[0072] When the flooding state detection unit 104 detects the occurrence of the flooding state, the vehicle control unit 105 operates the vehicle U in the flooding emergency mode in order to avoid stopping the engine 10 due to the blockage of the exhaust pipe 30. It should be noted that when the flooding state detection unit 104 does not detect the occurrence of the flooding state (i.e., the normal state), the vehicle control unit 105 operates the vehicle U in, for example, the best fuel efficiency mode (a normal operation mode that gives priority to energy efficiency and exhaust gas reduction).

[0073] Specifically, the vehicle control unit 105 instructs the engine 10 to increase the engine speed from the operating state in the optimal fuel efficiency mode in the flooding emergency mode. As a result, the exhaust flow rate discharged from the engine 10 is increased, and the intrusion of water into the exhaust pipe 30 is suppressed. In other words, the flooding state in the exhaust pipe 30 is prevented from further deteriorating, and the risk of the engine 10 stopping is reduced. It should be noted that at this time, the vehicle control unit 105 may also change the control map (for example, a control map based on torque) used to determine the engine speed in the optimal fuel efficiency mode (a normal operation mode that prioritizes energy efficiency) to a control map for the flooding emergency mode to achieve such control.

[0074] In addition, the vehicle control unit 105 prohibits the transmission 12 from upshifting in the flooding emergency mode, and makes it perform downshifting from the speed ratio set in the best fuel efficiency mode. In this way, the engine load for ensuring the driving force for driving the vehicle U is reduced, and the risk of the engine 10 stopping is reduced. It should be noted that at this time, if the speed ratio of the transmission 12 is already the minimum (that is, in the first gear), the vehicle control unit 105 does not perform any special processing.

[0075] In addition, in the flooding emergency mode, the vehicle control unit 105 increases the opening of the intake throttle valve 23 and / or the exhaust brake valve 32 from the opening of the intake throttle valve 23 and / or the exhaust brake valve 32 set in the best fuel efficiency mode. As a result, the engine load for ensuring the driving force for driving the vehicle U is reduced, and the risk of the engine 10 stopping is reduced. It should be noted that at this time, if the opening of the intake throttle valve 23 or the exhaust brake valve 32 is already in a fully open state, the vehicle control unit 105 does not perform any special processing.

[0076] In addition, the vehicle control unit 105 stops the operation of auxiliary machines (referring to air conditioning devices and oil pumps, etc., which are auxiliary devices operated by the driving force of the engine 10. The same applies hereinafter) (not shown) mounted on the vehicle U in the flood emergency mode. In other words, by stopping the operation of auxiliary machines that are not necessary for the vehicle U to travel, the engine load is reduced and the risk of the engine 10 stopping is reduced.

[0077] It should be noted that the vehicle control unit 105 may execute only any one of the above-mentioned controls in the flood emergency mode, or may execute all of the controls in order to more effectively reduce the risk of the engine 10 stopping.

[0078] When the flooding detection unit 104 detects the occurrence of the flooding state, the notification unit 106 notifies the occupants of the vehicle U and / or the outside of the vehicle U of the situation of the vehicle U (ie, the situation where there is a risk of engine stopping). Here, the notification unit 106 may use any notification method.

[0079] The notification unit 106 may, for example, use an indicator display device mounted on the vehicle U to notify the passengers of the vehicle U of the situation of the vehicle U. In addition, the notification unit 106 may, for example, use a communication device mounted on the vehicle U to notify a traffic management system outside the vehicle U of the situation of the vehicle U. In addition, the notification unit 106 may, for example, use a lighting device (e.g., a hazard warning light or a brake light) mounted on the vehicle U to notify pedestrians around the vehicle U of the situation of the vehicle U. In addition, the notification unit 106 may perform all of these notification processes.

[0080] As a result, for example, it is possible to encourage passengers of vehicle U to avoid the current driving path of vehicle U, or to make pedestrians around vehicle U or a traffic management system outside vehicle U understand that vehicle U is performing emergency driving.

[0081] [ECU operation flow]

[0082] Figure 4 1 is a diagram showing an example of an operation flow of the ECU 100 according to the present embodiment. Figure 4 The flowchart shown is, for example, a process that the ECU 100 repeatedly executes at predetermined intervals (for example, every 100 msec) according to a computer program.

[0083] In step S1 , the ECU 100 (the first exhaust temperature information acquisition unit 101 ) acquires the sensor value of the first temperature sensor 51 in order to grasp the exhaust temperature on the upstream side in the exhaust pipe 30 .

[0084] In step S2 , the ECU 100 (the second exhaust temperature information acquisition unit 102 ) acquires the sensor value of the second temperature sensor 52 in order to grasp the downstream exhaust temperature in the exhaust pipe 30 .

[0085] In step S3 , the ECU 100 (exhaust pressure information acquisition unit 103 ) acquires the sensor value of the pressure sensor 53 in order to grasp the exhaust pressure in the exhaust pipe 30 .

[0086] In step S4, the ECU 100 (water immersion state detection unit 104) determines whether the increase in exhaust pressure per unit time is greater than the first threshold value. Here, if the increase in exhaust pressure per unit time is greater than the first threshold value (S4: Yes), the ECU 100 proceeds to step S5. If the increase in exhaust pressure per unit time is less than the first threshold value (S4: No), the ECU 100 does not perform any special processing and ends. Figure 4 Flowchart of the process.

[0087] In step S5, the ECU 100 (waterlogging state detection unit 104) determines whether the amount of decrease in the downstream exhaust temperature relative to the upstream exhaust temperature per unit time is greater than the second threshold value. Here, if the amount of decrease in the downstream exhaust temperature relative to the upstream exhaust temperature per unit time is greater than the second threshold value (S5: Yes), the ECU 100 proceeds to step S6. If the amount of decrease in the downstream exhaust temperature relative to the upstream exhaust temperature per unit time is less than the second threshold value (S5: No), the ECU 100 does not perform any special processing and ends. Figure 4 Flowchart of the process.

[0088] In step S6, the ECU 100 (water immersion state detection unit 104) determines that water has entered the exhaust pipe 30, and sets a water immersion state flag indicating the immersion state. It should be noted that, preferably, once the ECU 100 sets the water immersion state flag, even if it is determined as "no" in step S4 or step S5 of the subsequent routine, the water immersion state flag is not released until a predetermined time has passed.

[0089] In step S7, the ECU 100 (vehicle control unit 105) causes each part of the vehicle U to operate in the flooding emergency mode. At this time, the ECU 100 issues the following instructions, for example: an increase instruction for the engine speed of the engine 10, a downshift execution instruction for the transmission 12, an increase instruction for the opening of the intake throttle valve 23 and / or the exhaust brake valve 32, and an operation stop instruction for auxiliary machines.

[0090] In step S8 , the ECU 100 (notification unit 106 ) uses a communication device, an indicator display device, a lighting device, etc. mounted on the vehicle U to notify passengers of the vehicle U and / or the outside of the vehicle U of the situation of the vehicle U (ie, the situation where there is a risk of engine stopping).

[0091] The ECU 100 of the present embodiment can detect the flooding of the exhaust pipe 30 at an early stage through such processing, and can suppress the vehicle from becoming unable to travel autonomously due to the stop of the engine 10 when the flooding of the exhaust pipe 30 occurs.

[0092] [Effect]

[0093] As described above, the ECU 100 of the present embodiment has a function of detecting the water intrusion state in the exhaust pipe 30 based on the upstream exhaust temperature, the downstream exhaust temperature and the exhaust pressure. At this time, the ECU 100 determines whether the increase in exhaust pressure per unit time is above a first threshold value, and determines whether the decrease in the downstream exhaust temperature relative to the upstream exhaust temperature per unit time is above a second threshold value. Only when these two conditions are met is it determined that water has intruded in the exhaust pipe 30.

[0094] This makes it possible to detect early and accurately the state in which water has entered the exhaust pipe 30. This detection method is also useful in that the vehicle U can detect the state in which water has entered the exhaust pipe 30 using an existing temperature sensor and pressure sensor.

[0095] Furthermore, the ECU 100 of the present embodiment operates the vehicle U in the flooding emergency mode when water enters the exhaust pipe 30 . Thus, even when water enters the exhaust pipe 30 , the risk of the engine 10 stopping can be reduced.

[0096] In the above embodiment, the ECU 100 is applied to a diesel engine vehicle as an example of the vehicle U to which the ECU 100 is applied. However, the ECU 100 of the present invention can also be applied to a gasoline engine vehicle.

[0097] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the claims. The technology described in the claims includes various modifications and changes made to the specific examples described above.

[0098] This application is based on Japanese patent application (Japanese Patent Application No. 2020-140169) filed on August 21, 2020, the contents of which are incorporated herein by reference.

[0099] Industrial Applicability

[0100] According to the vehicle control device of the present invention, it is possible to detect the flooding state of the exhaust pipe of the engine at an early stage.

[0101] Description of Reference Numerals

[0102] U Vehicle

[0103] 10 Engine

[0104] 12 Transmission

[0105] 20 Intake pipe

[0106] 20a Air inlet

[0107] 21 Air filter

[0108] 22 Turbocharger

[0109] 23 Intake throttle valve

[0110] 30 Exhaust pipe

[0111] 31 EGR device

[0112] 32 Exhaust brake valve

[0113] 40 Exhaust purification device

[0114] 41 Oxidation Catalyst

[0115] 42 PM filter

[0116] 43 SCR catalyst

[0117] 51 First temperature sensor

[0118] 52 Second temperature sensor

[0119] 53 Pressure sensor

[0120] 100ECU

[0121] 101 First exhaust gas temperature information acquisition unit

[0122] 102 Second exhaust gas temperature information acquisition unit

[0123] 103 Exhaust pressure information acquisition unit

[0124] 104 Water immersion detection unit

[0125] 105 Vehicle Control Unit

[0126] 106 Notification Department

Claims

1. A control device for a vehicle having an internal combustion engine, characterized in that: include: a first exhaust gas temperature information acquisition unit that acquires information related to a first exhaust gas temperature measured at a first location on the upstream side of the exhaust gas purification device in the exhaust pipe of the internal combustion engine; a second exhaust gas temperature information acquiring unit that acquires information related to a second exhaust gas temperature measured at a second location on the downstream side of the exhaust gas purification device in the exhaust pipe; an exhaust pressure information acquisition unit, which acquires information related to the exhaust pressure measured in the exhaust pipe; as well as a water intrusion state detecting unit for detecting a water intrusion state in the exhaust pipe based on the first exhaust temperature, the second exhaust temperature, and the exhaust pressure; The water submersion state detection unit determines that the water submersion state has occurred when an increase in the exhaust pressure per unit time is equal to or greater than a first threshold and a decrease in the second exhaust temperature relative to the first exhaust temperature per unit time is equal to or greater than a second threshold.

2. The control device according to claim 1, wherein: A vehicle control unit is provided for operating the vehicle in a flooding emergency mode in order to suppress the internal combustion engine from stopping when the flooding state is detected by the flooding state detection unit.

3. The control device according to claim 2, wherein: In the flooding emergency mode, the vehicle control unit increases the engine speed of the internal combustion engine.

4. The control device according to claim 2, wherein: In the flooding emergency mode, the vehicle control unit causes a transmission of the vehicle to perform a downshift.

5. The control device according to claim 2, wherein: In the flooding emergency mode, the vehicle control unit increases the opening of a valve provided in an intake pipe of the internal combustion engine and / or a valve provided in an exhaust pipe.

6. The control device according to claim 2, wherein: In the flooding emergency mode, the vehicle control unit stops the operation of auxiliary machines mounted on the vehicle.

7. The control device according to claim 1, wherein: A notification unit is provided for notifying a passenger of the vehicle and / or an outside of the vehicle that water has entered the exhaust pipe when the water entry detection unit detects the entry state.

8. The control device according to claim 7, wherein: The notification unit notifies a passenger of the vehicle and / or an exterior of the vehicle that water has entered the exhaust pipe using at least one of a communication device, an indicator display device, or a lighting device mounted on the vehicle.

9. A vehicle, characterized in that: Comprising the control device as claimed in claim 1.

10. A control method for a vehicle having an internal combustion engine, characterized in that: include: a first process of acquiring information related to a first exhaust gas temperature measured at a first location on an upstream side of an exhaust gas purification device in an exhaust pipe of the internal combustion engine; a second process of acquiring information related to a second exhaust gas temperature measured at a second location on the downstream side of the exhaust gas purification device in the exhaust pipe; a third process of acquiring information related to the exhaust pressure measured in the exhaust pipe; as well as a fourth process of detecting a water intrusion state in the exhaust pipe based on the first exhaust temperature, the second exhaust temperature, and the exhaust pressure; In the fourth process, it is determined that the immersion state has occurred when the increase amount of the exhaust pressure per unit time is equal to or greater than a first threshold and the decrease amount of the second exhaust temperature relative to the first exhaust temperature per unit time is equal to or greater than a second threshold.

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