Vehicle control device

Abstract

To provide a vehicle control device capable of preventing water from being sucked through an intake duct of an engine when traveling on a road with a high water level.SOLUTION: A vehicle control device for a vehicle mounted with an engine and a traveling motor as power sources comprises: a first acquisition section which acquires a water level on a road surface in a travel direction of a vehicle; a second acquisition section which acquires a travel speed of the vehicle; a third acquisition section which acquires a power storage amount of a battery supplying drive power to the traveling motor; and a control section which prohibits the activation of the engine when the water level is greater than or equal to a first threshold, the travel speed is greater than or equal to a second threshold, and the power storage amount is greater than or equal to a third threshold.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a control device for a vehicle equipped with an internal combustion engine (engine) and an electric motor (travel motor) as power sources. [Background technology]

[0002] Patent Document 1 discloses a vehicle control device that can prevent water from entering the exhaust passage. This control device describes a method of using exhaust pressure to prevent water from entering the exhaust passage by prohibiting the internal combustion engine from stopping when the internal combustion engine is operating and starting the internal combustion engine when the internal combustion engine is stopped when the water level around the vehicle is equal to or higher than a predetermined value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-218911 Summary of the Invention [Problem to be solved by the invention]

[0004] The vehicle control device described in Patent Document 1 is configured to prevent water from entering the exhaust passage by using exhaust pressure. However, with this control device configuration, the engine is operated when the water level is high, which raises the risk of water being drawn into the engine's intake duct. If water is drawn into the engine through the intake duct, it can damage the engine and reduce its durability.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a vehicle control device that can prevent water from being sucked into the engine intake duct when driving on a road with a high water level. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the disclosed technology is a control device for a vehicle equipped with an engine and a driving motor as power sources, comprising: a first acquisition unit that acquires the water level on the road surface in the direction of vehicle travel; a second acquisition unit that acquires the vehicle's traveling speed; a third acquisition unit that acquires the amount of stored electricity in a battery that supplies driving power to the driving motor; and a control unit that prohibits the engine from operating when the water level is equal to or greater than a first threshold, the traveling speed is equal to or greater than a second threshold, and the amount of stored electricity is equal to or greater than a third threshold. [Effects of the Invention]

[0007] According to the vehicle control device of the present disclosure, when the vehicle is traveling on a road surface with a high water level, it is possible to prevent water from being sucked into the engine intake duct. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a functional block diagram showing a schematic configuration of a vehicle control device according to an embodiment of the present invention. [Figure 2] A flowchart of a power source control process executed by a vehicle control device. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiment> [composition] 1 is a functional block diagram illustrating an outline of a vehicle control device 100 and its peripheral units according to an embodiment of the present disclosure. The control device 100 illustrated in FIG. 1 includes an acquisition unit 110 and a control unit 120.

[0010] The control device 100 of this embodiment can be used in vehicles such as hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs) that are equipped with an internal combustion engine 200 and a traction motor 300 as power sources (driving force sources).

[0011] The acquisition unit 110 can acquire information about the water level on the road surface in the traveling direction of the vehicle (first acquisition unit). Typically, the acquisition unit 110 acquires the depth and size of puddles (such as flooded underpasses) on the road ahead of the vehicle. When the vehicle is in reverse (the shift position is in the reverse (R) position), the acquisition unit 110 may acquire the water level on the road surface behind the vehicle. This water level on the road surface can be acquired using a detection device (not shown) such as a water level sensor or a water pressure sensor mounted on the vehicle, or various sensors capable of estimating the water level on the road surface (imaging devices such as cameras used for controlling advanced safety driving and autonomous driving).

[0012] The acquisition unit 110 can also acquire the vehicle's traveling speed (vehicle speed) (second acquisition unit). The vehicle's traveling speed can be acquired using a detection device such as a speed sensor (not shown) mounted on the vehicle.

[0013] Furthermore, the acquisition unit 110 can acquire the amount of stored power in a battery (not shown) that supplies power for driving the traction motor 300, i.e., the remaining battery capacity for EV driving (third acquisition unit). This battery is a secondary battery configured to be rechargeable, such as a lithium ion battery, and is a drive battery that supplies the power necessary to drive the traction motor 300. This amount of stored power (SOC: State Of Charge) can be acquired using detection devices (not shown), such as various sensors that monitor the physical quantities (current, voltage, temperature, etc.) of the battery.

[0014] The control unit 120 can control whether to permit or prohibit the driving of the engine 200 and the traction motor 300 based on the water level on the road surface, the vehicle's traveling speed, and the amount of electricity stored in the battery, all of which are acquired by the acquisition unit 110. Details of this control by the control unit 120 will be described later.

[0015] Note that part or all of the above-described control device 100 may be configured by an electronic control unit (ECU) that typically includes a processor such as a microcomputer, a memory, an input / output interface, etc. This electronic control unit can realize part or all of the functions performed by the above-described acquisition unit 110 and control unit 120 by having the processor read and execute a program stored in the memory.

[0016] [control] Next, the control performed by the vehicle control device 100 according to an embodiment of the present disclosure will be described with further reference to Fig. 2. Fig. 2 is a flowchart illustrating the processing procedure of power source control executed by each component of the vehicle control device 100.

[0017] The power source control illustrated in FIG. 2 is started, for example, when the power supply of the vehicle system is turned on (READY-ON), and is repeatedly executed until the power supply of the vehicle system is turned off (READY-OFF).

[0018] (Step S201) The acquisition unit 110 acquires the water level on the road surface in the traveling direction of the vehicle. Once the water level on the road surface is acquired by the acquisition unit 110, the process proceeds to step S202.

[0019] (Step S202) Control unit 120 determines whether the water level on the road surface acquired by acquisition unit 110 is equal to or higher than a predetermined reference water level (first threshold value). This determination is made to determine whether there is a possibility that water present on the road surface will flow into engine 200 through the intake port of the intake duct of engine 200. Therefore, the first threshold value, which is the reference water level, is appropriately set based on the water level on the road surface at which water from a puddle pushed up by a bumper or the like in front of the vehicle when driving (passing) the road surface with a puddle may reach the intake port of the intake duct of engine 200. For example, it can be inferred that the higher the water level, the greater the amount of water pushed up by a bumper or the like in front of the vehicle, and therefore the greater the possibility that water will flow into engine 200 through the intake port of the intake duct of engine 200.

[0020] If the water level on the road surface is equal to or greater than the first threshold (step S202, Yes), the process proceeds to step S203. On the other hand, if the water level on the road surface is less than the first threshold (step S202, No), the process proceeds to step S208.

[0021] (Step S203) The acquisition unit 110 acquires the traveling speed (vehicle speed) of the vehicle. Once the traveling speed of the vehicle is acquired by the acquisition unit 110, the process proceeds to step S204.

[0022] (Step S204) Control unit 120 determines whether the traveling speed (vehicle speed) of the vehicle acquired by acquisition unit 110 is equal to or greater than a predetermined reference speed (second threshold value). This determination is made to determine whether there is a possibility that water present on the road surface will flow into engine 200 through the intake port of the intake duct of engine 200. Therefore, the second threshold value, which is the reference speed, is appropriately set based on the vehicle speed at which water from a puddle pushed up by a bumper or the like in front of the vehicle when traveling (passing) over a puddled road surface or the like is likely to reach the intake port of the intake duct of engine 200. For example, it can be inferred that the faster the vehicle speed, the more likely water is pushed up to a higher position by a bumper or the like in front of the vehicle (water splashes up), and therefore the more likely it is that water will flow into engine 200 through the intake port of the intake duct of engine 200.

[0023] If the vehicle speed is equal to or greater than the second threshold (step S204, Yes), the process proceeds to step S205. On the other hand, if the vehicle speed is less than the second threshold (step S204, No), the process proceeds to step S208.

[0024] (Step S205) The acquisition unit 110 acquires the amount of power stored in the battery (remaining battery power for EV driving). Once the acquisition unit 110 acquires the amount of power stored in the battery, the process proceeds to step S206.

[0025] (Step S206) The control unit 120 determines whether the amount of stored power in the battery (remaining battery power for EV driving) acquired by the acquisition unit 110 is equal to or greater than a predetermined reference amount of stored power (third threshold). This determination is made to determine whether the vehicle can be driven stably continuously using only the power currently stored in the battery for EV driving. Therefore, the third threshold, which is the reference amount of stored power, is appropriately set based on various conditions such as the distance to the destination or charging point and the gradient of the driving route (whether regenerative charging is performed or not). For example, if the amount of stored power in the battery is lower than the control target value, it can be determined that charging by the engine 200 is necessary and that EV driving alone is not appropriate.

[0026] If the amount of stored power is equal to or greater than the third threshold (step S206, Yes), the process proceeds to step S207. On the other hand, if the amount of stored power is less than the third threshold (step S206, No), the process proceeds to step S208.

[0027] (Step S207) The control unit 120 determines that there is a possibility that water may reach the intake duct of the engine 200, and performs control to prohibit the operation of the engine 200 and permit the operation of the traction motor 300. This control allows the vehicle to run only in EV mode using the traction motor 300 (transition to EV running mode). Specifically, if the vehicle is running on fuel using the engine 200 at the time of the above determination, the engine 200 is stopped and the vehicle is switched to EV running using the traction motor 300. On the other hand, if the vehicle is running on EV mode using the traction motor 300 at the time of the above determination, the control unit 120 controls the vehicle so that it cannot subsequently switch to running the engine 200. When the operation of the engine 200 is prohibited and the operation of the traction motor 300 is permitted, the process proceeds to step S201.

[0028] When the process of step S207 is performed, the driving output may be reduced or the power consumption of on-board electrical equipment (such as an air conditioner) may be reduced in order to maintain the EV driving state. However, it is desirable that such reduction processes be performed after informing the driver that the mode has been forcibly switched to the EV driving mode so as not to cause the driver any discomfort.

[0029] (Step S208) The control unit 120 determines that there is no possibility of water reaching the intake duct of the engine 200, and performs control to permit the operation of both the engine 200 and the traction motor 300. This control enables the vehicle to perform hybrid driving using both the engine 200 and the traction motor 300 (transition to hybrid driving mode). When the operation of both the engine 200 and the traction motor 300 is permitted, the process proceeds to step S201.

[0030] The order in which the above-mentioned processes for obtaining the water level on the road surface and determining the height (steps S201-S202), the process for obtaining the vehicle's traveling speed and determining the speed (steps S203-S204), and the process for obtaining the battery's stored power and determining the capacity (steps S205-S206) are performed is not limited to that shown in Figure 2, and may be performed in any order.

[0031] <Actions and Effects> As described above, the vehicle control device 100 according to one embodiment of the present disclosure detects whether the water level on the road surface pushed up by the bumper in front of the vehicle while driving has reached a level that could potentially reach the intake port of the vehicle's internal combustion engine intake duct, based on information from a sensor installed in the vehicle that detects the water level on the road surface and information from a sensor that detects the vehicle speed.

[0032] This makes it possible to prohibit the operation of the internal combustion engine and switch to EV driving using only the electric motor, taking into account information on the remaining battery charge (amount of stored electricity) for EV driving, if it is determined that water pushed up by the bumper at the front of the vehicle while driving may flow into the engine intake path through the intake port of the internal combustion engine intake duct.

[0033] Therefore, for example, if a vehicle enters a road that has been flooded due to heavy rain, it is possible to prevent damage to the internal combustion engine caused by water being sucked into the engine's intake duct, reduce repair costs for the internal combustion engine, and ensure the vehicle's driving performance after escaping the flooded area.

[0034] <Application example> In the above embodiment, the water level on the road surface must fall below the first threshold value in order to return the drive of engine 200 from the prohibited state to the permitted state. However, even if the water level on the road surface is equal to or greater than the first threshold value, the drive of engine 200 may be forcibly permitted if, for example, the driver's accelerator pedal depression amount exceeds a certain value or there is an explicit instruction from the driver (such as pressing a physical switch or selecting on a display monitor). Such control ensures that the vehicle can escape from a point where the water level on the road surface is high.

[0035] Furthermore, in the above embodiment, the engine 200 is simply permitted to operate normally when there is no possibility of water entering through the intake port of the intake duct of the engine 200. However, if the amount of charge stored in the battery is lower than a predetermined value when the engine 200 is permitted to operate, the operating output of the engine 200 can be intentionally increased to ensure that the amount of charge stored in the battery is sufficient.

[0036] Furthermore, if the vehicle system forcibly prohibits the operation of engine 200, there is a possibility that the driver may feel uneasy that the vehicle will be unable to travel due to the stop of engine 200. Therefore, in order to alleviate this sense of uneasiness, the driver may be notified in advance that the operation of engine 200 will be stopped and the vehicle will switch to EV driving if the water level on the road surface rises further. Furthermore, after switching to EV driving, the driver may be notified in advance of the conditions under which the operation of engine 200 will resume (such as a drop in the water level on the road surface or a decrease in vehicle speed). [Industrial Applicability]

[0037] The vehicle control device of the present disclosure can be used in a vehicle equipped with an internal combustion engine (engine) and an electric motor (driving motor) as a power source. [Explanation of symbols]

[0038] 100 control device 110 Acquisition Department 120 control section 200 Engine 300 driving motor

Claims

[Claim 1] A control device for a vehicle equipped with an engine and a driving motor as power sources, a first acquisition unit that acquires a water level on a road surface in a traveling direction of the vehicle; a second acquisition unit that acquires a traveling speed of the vehicle; a third acquisition unit that acquires a stored charge amount of a battery that supplies power for driving the driving motor; a control unit that prohibits driving of the engine when the water level is equal to or greater than a first threshold, the traveling speed is equal to or greater than a second threshold, and the amount of stored electricity is equal to or greater than a third threshold. Vehicle control device.

Images