Hybrid vehicle

Abstract

To further appropriately deal with a case where a driving force of a vehicle is limited due to a restriction on an output of an engine.SOLUTION: A hybrid vehicle includes: an engine with a port injection valve capable of outputting power for driving; an electric motor capable of outputting power for driving; an electricity storage device that exchanges electric power with the electric motor; and a control device that limits engine output when the engine is cold in order to warm up an exhaust purification device attached to an exhaust system of the engine. The control device prohibits driving for a predetermined time when a system is started in a state where an engine coolant temperature is below a predetermined temperature while the vehicle is parked in a parking area on a highway or within a predetermined distance from a merging point on a main highway.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to hybrid vehicles. [Background technology]

[0002] Conventionally, hybrid vehicles of this type have been proposed that limit engine output until the engine has finished warming up (see, for example, Patent Document 1). In these hybrid vehicles, when engine output is limited, the engine is controlled within the output limit range relative to the required output, and the motor is controlled so that the remaining output is covered by output from the motor. This limits engine output to prevent emissions from worsening and also prevents a shortage of total vehicle output. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-146789 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the hybrid vehicle described above, when the engine output is limited, there are cases where the driving force is insufficient even when the motor output is taken into consideration. On ordinary roads that do not require a large driving force, it is possible to drive normally even with the engine output limited. However, when merging onto a highway, if the engine output is limited, the driving force is insufficient and sufficient acceleration cannot be obtained.

[0005] The hybrid vehicle of the present disclosure has a primary objective of more appropriately dealing with a situation in which the driving force of the vehicle is limited due to a restriction on the engine output. [Means for solving the problem]

[0006] The hybrid vehicle of the present disclosure employs the following measures to achieve the above-mentioned main object.

[0007] The hybrid vehicle disclosed herein is a hybrid vehicle including an engine having a port injection valve capable of outputting power for running, an electric motor capable of outputting power for running, an electricity storage device that exchanges electric power with the electric motor, and a control device that limits the output of the engine when the engine is cold in order to warm up an exhaust purification device attached to an exhaust system of the engine, The control device is characterized in that when the vehicle is stopped within a predetermined distance from a parking area on a highway or a merging point on the main highway and the system is started in a state where the temperature of the engine cooling water is below a predetermined temperature, the control device prohibits driving for a predetermined time.

[0008] In the hybrid vehicle disclosed herein, when the vehicle is parked within a predetermined distance from a highway parking area or a highway merging point and the engine coolant temperature is below a predetermined temperature, the system prohibits the vehicle from traveling for a predetermined period of time. This prevents insufficient acceleration due to a lack of driving force when merging onto the highway. As a result, the system can more appropriately deal with the limitation of vehicle driving force due to the limited engine output. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram showing an outline of the configuration of a hybrid vehicle 20 according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a diagram showing the outline of the configuration of an engine 22. [Figure 3] 10 is a flowchart showing an example of a system startup process executed by the HVECU 70. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, an embodiment for carrying out the present disclosure will be described. Fig. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as one embodiment of the present disclosure. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50 as an electricity storage device, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70. The engine 22 and the HVECU 70 correspond to the engine device.

[0011] The engine 22 is an internal combustion engine that uses gasoline or other fuel to output power, and is connected to a carrier 34 of a planetary gear 30 via a damper 28. FIG. 2 is a schematic diagram illustrating the configuration of the engine 22. As shown in the figure, the engine 22 draws air purified by an air cleaner 122 into an intake pipe 123, passes the air through a throttle valve 124, and injects fuel from a fuel injection valve 126 attached to an intake port to mix the air and fuel. The mixture is then drawn into a combustion chamber 129 via an intake valve 128. The drawn mixture is then explosively combusted by an electric spark generated by an ignition plug 130, and the resulting energy pushes down a piston 132, which then moves in a reciprocating motion, converting it into rotational motion of the crankshaft (output shaft) 26. Exhaust gas is discharged from the combustion chamber 129 via an exhaust valve 131 into an exhaust pipe 133, where it is discharged into the outside air via a purification device 134 and a PM filter 136. The purification device 134 has a purification catalyst (three-way catalyst) 134a that purifies harmful components in the exhaust gas, such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).

[0012] The engine ECU 24 is configured as a microcomputer centered around a CPU (not shown). The engine ECU 24 receives inputs such as a crank angle θcr from a crank position sensor 140 that detects the rotational position of the crankshaft 26 of the engine 22 and a coolant temperature Tw from a water temperature sensor 142 that detects the temperature of the coolant for the engine 22. Other inputs include cam angles θci and θco from a cam position sensor 144 that detects the rotational positions of an intake camshaft that opens and closes the intake valve 128 and an exhaust camshaft that opens and closes the exhaust valve 131, a throttle opening TH from a throttle position sensor 124a that detects the position of the throttle valve 124, an intake air amount Qa from an air flow meter 148 attached to the intake pipe 123, an intake air temperature Ta from a temperature sensor 149 attached to the intake pipe 123, an air-fuel ratio AF from an air-fuel ratio sensor 135a attached to the exhaust pipe 133, and an oxygen signal O2 from an oxygen sensor 135b attached to the exhaust pipe 133.

[0013] The engine ECU 24 outputs a control signal to a throttle motor 124b that adjusts the position of the throttle valve 124, a control signal to a fuel injection valve 126, a control signal to an ignition plug 130, and the like. The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 140, and calculates the temperature (catalyst temperature) Tc of the purification catalyst 134a of the purification device 134 based on the cooling water temperature Tw from the water temperature sensor 142, etc. The engine ECU 24 also calculates an integrated value Ga of the intake air amount Qa from the air flow meter 148 since the start of the engine 22, and a load factor KL (the ratio of the volume of air actually taken in one cycle to the stroke volume per cycle of the engine 22) based on the intake air amount Qa and the rotation speed Ne of the engine 22. The engine ECU 24 also calculates a filter temperature Tf as the temperature of the PM filter 136 based on the rotation speed Ne of the engine 22 and the load factor KL.

[0014] 1, the planetary gear 30 is configured as a single-pinion planetary gear mechanism. A rotor of a motor MG1 is connected to a sun gear of the planetary gear 30, and a drive shaft 36, which is coupled to drive wheels 39a, 39b via a differential gear 38, is connected to a ring gear. The carrier is also connected to the crankshaft 26 of the engine 22 via a damper 28.

[0015] The motor MG1 is configured, for example, as a synchronous generator motor, and as described above, its rotor is connected to the sun gear 31 of the planetary gear 30. The motor MG2 is configured, for example, as a synchronous generator motor, and its rotor is connected to the drive shaft 36. The inverters 41 and 42 are used to drive the motors MG1 and MG2 and are connected to a battery 50 via a power line 54. A smoothing capacitor 57 is attached to the power line 54. The motors MG1 and MG2 are rotated and driven by a motor electronic control unit (hereinafter referred to as "motor ECU") 40 that controls the switching of multiple switching elements (not shown) of the inverters 41 and 42. The motor ECU 40 is configured as a microcomputer centered around a CPU (not shown). The motor ECU 40 receives inputs such as rotational positions θm1, θm2 from rotational position detection sensors 43, 44 that detect the rotational positions of the rotors of motors MG1, MG2, and phase currents Iu1, Iv1, Iu2, Iv2 from current sensors (not shown) that detect currents flowing through each phase of motors MG1, MG2. The motor ECU 40 outputs switching control signals to multiple switching elements of inverters 41, 42. The motor ECU 40 calculates electrical angles θe1, θe2, angular velocities ωm1, ωm2, and rotation speeds Nm1, Nm2 of motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of motors MG1, MG2 from the rotational position detection sensors 43, 44.

[0016] The battery 50 is configured as, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery, and is connected to a power line 54. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as "battery ECU") 52. Although not shown, the battery ECU 52 is configured as a microcomputer centered around a CPU. The battery ECU 52 receives inputs such as the voltage Vb of the battery 50 from a voltage sensor 51a attached between the terminals of the battery 50, the current Ib of the battery 50 from a current sensor 51b attached to the output terminal of the battery 50, and the temperature Tb of the battery 50 from a temperature sensor 51c attached to the battery 50. The battery ECU 52 calculates the power storage rate SOC based on the integrated value of the current Ib of the battery 50 from the current sensor 51b.

[0017] Although not shown, the HVECU 70 is configured as a microcomputer centered around a CPU. The HVECU 70 receives inputs such as an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operating position of a shift lever 81, an accelerator opening Acc from an accelerator pedal position sensor 84 that detects the depression amount of an accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 that detects the depression amount of a brake pedal 85, and a vehicle speed V from a vehicle speed sensor 88. The HVECU 70 outputs a control signal to a display device 90 that is incorporated in an installation panel in front of the driver's seat and is capable of audio output and display. The HVECU 70 communicates with the engine ECU 24, the motor ECU 40, the battery ECU 52, and the navigation device 60.

[0018] The navigation device 60 includes a main body 62 with a built-in control unit, a GPS antenna 64 that receives information about the current location of the vehicle, and a display 66. The display 66 can also serve as the display device 90. The control unit of the main body 62 has a storage medium (e.g., a hard disk or SSD) that stores map information and the like. The map information includes service information (e.g., tourist information, parking lots, etc.) and road information for each driving section (e.g., between traffic lights and between intersections) stored as a database. The road information includes distance information, road width information, number of lanes information, area information (urban or suburban), type information (general road or expressway), gradient information, legal speed limit, number of traffic lights, turning radius of each curve, etc. The display 66 displays various information such as information about the current location of the vehicle and the planned driving route to the destination, and is configured as a touch panel display that allows the user to input various instructions. When a destination is set by a user operating the display 66, the main body 62 of the navigation device 60 sets a planned driving route from the current location of the vehicle to the destination based on map information stored in the main body 62 and the current location and destination of the vehicle obtained from the GPS antenna 64, and displays the set planned driving route on the display 66 to provide route guidance.

[0019] In the hybrid vehicle 20 of the embodiment configured as described above, when the temperature Tw of the coolant of the engine 22 is below a predetermined temperature Tref at the time of system startup, in order to prevent the purification catalyst 134a of the purification device 134 from being unable to fully function and thereby causing emissions to deteriorate, the engine 22 is started to perform a catalyst warm-up operation, and a limit is imposed on the driving force of the vehicle (the output of the engine 22) until a predetermined time (for example, 60 seconds) required for the purification catalyst 134a to be able to function to a certain extent has elapsed. Note that the predetermined temperature Tref can be 0°C, 10°C, or the like.

[0020] Next, the operation of the hybrid vehicle 20 of this embodiment configured as described above, particularly the operation when the system is started up in a cold state at a service area or parking area on a highway, etc. will be described. Figure 3 is a flowchart showing an example of a system start-up process executed by the HVECU 70.

[0021] When the system startup process is executed, the HVECU 70 acquires the vehicle position (step S100) and the coolant temperature Tw (step S110). The vehicle position detected by the GPS antenna 64 of the navigation device 60 can be acquired, and the coolant temperature Tw detected by the water temperature sensor 142 can be acquired.

[0022] Then, it is determined whether the coolant temperature Tw is less than a predetermined temperature Tref (step S120). If it is determined that the coolant temperature Tref is equal to or greater than the predetermined temperature Tref, then travel is permitted (step S180), and the process ends. On the other hand, if it is determined that the coolant temperature Tw is less than the predetermined temperature, then it is determined whether the vehicle is located in a service area or parking area on a highway, or within a predetermined distance from an entrance to the highway (step S130). This determination can be made based on map information from the navigation device 60. If it is determined that the vehicle is not located in a service area or parking area on a highway, or within a predetermined distance from an entrance to the highway, then travel is permitted (step S180), and the process ends. In this case, as described above, the engine 22 is started, catalyst warm-up operation is performed, and restrictions are imposed on the vehicle's driving force until the predetermined time has elapsed.

[0023] If step S130 determines that the vehicle is located in a service area or parking area on a highway, or is within a predetermined distance from a highway entrance, the process prohibits driving (step S140), notifies the driver that driving is prohibited (step S150), and waits for a predetermined time to elapse (step S160). After the predetermined time has elapsed, the process notifies the driver that driving is permitted (step S170), permits driving (step S180), and terminates the process. Prohibiting driving can be achieved, for example, by masking the signal from shift lever 81 even when the shift lever is operated to D, R, S, B, or the like. The notification that driving is prohibited can be provided by audio output and visual output on display device 90, such as, "The engine is cold and cannot accelerate sufficiently, making it unsuitable for merging onto the highway main lane. Please wait 60 seconds until driving is permitted." The notification that driving is permitted can be made by outputting a message such as "Sorry to keep you waiting. Driving is now permitted" by voice and visual output on the display device 90.

[0024] In the hybrid vehicle 20 of the embodiment described above, when the system is started, if the engine 22 coolant temperature Tw is below the predetermined temperature Tref and the vehicle is located in a service area or parking area on a highway, or within a predetermined distance from the highway entrance, driving is prohibited for a predetermined time. This prevents insufficient acceleration due to insufficient driving force when merging onto a main lane on a highway. As a result, it is possible to more appropriately deal with a situation in which the vehicle's driving force is restricted because the engine 22 coolant temperature Tw is below the predetermined temperature Tref when the system is started. Furthermore, when driving is prohibited, a notification to that effect is provided, thereby informing the driver that driving is prohibited.

[0025] The present disclosure has been described above using embodiments, but the present disclosure is not limited to these embodiments in any way, and it goes without saying that the present disclosure can be embodied in various forms within the scope that does not deviate from the gist of the present disclosure. [Industrial Applicability]

[0026] The present disclosure is applicable to the hybrid vehicle manufacturing industry and the like. [Explanation of symbols]

[0027] 20 Hybrid vehicle, 22 Engine, 50 Battery, 60 Navigation device, 70 HVECU, 90 Display device, 134 Purification device, 142 Water temperature sensor, MG1, MG2 motor.

Claims

[Claim 1] A hybrid vehicle comprising an engine having a port injection valve capable of outputting power for running, an electric motor capable of outputting power for running, an electricity storage device that exchanges electric power with the electric motor, and a control device that limits the output of the engine when the engine is cold in order to warm up an exhaust purification device attached to an exhaust system of the engine, the control device prohibits the vehicle from traveling for a predetermined time when the system is started in a state where the temperature of the engine cooling water is below a predetermined temperature while the vehicle is stopped in a parking area on an expressway or within a predetermined distance from a merging point on a main line of the expressway, A hybrid vehicle characterized by

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