Vehicle control system

Abstract

This invention suppresses the occurrence of hunting, which is a phenomenon in which torque-up control, which increases the output torque of an internal combustion engine in response to atmospheric pressure, is frequently executed and stopped during idle operation of the internal combustion engine. [Solution] The vehicle control device of the present disclosure is a control device that performs torque-up control to increase the output torque of an internal combustion engine in accordance with atmospheric pressure during idle operation of the internal combustion engine, and performs torque-up control on the condition that at least the target idle speed of the internal combustion engine is less than or equal to a predetermined permitted speed, and the difference between the target idle speed and the actual speed of the internal combustion engine is within a predetermined allowable deviation range.

Description

Technical Field

[0001] The present disclosure relates to a control device for a vehicle including an internal combustion engine.

Background Art

[0002] Conventionally, a vehicle including an internal combustion engine having a supercharger, an automatic transmission connected to the internal combustion engine via a torque converter, and a control device for controlling the internal combustion engine and the automatic transmission is known (see, for example, Patent Document 1). The control device of this vehicle sets the temperature threshold higher as the atmospheric pressure is lower, and closes the waste gate valve of the supercharger so that the intake air amount increases when the temperature of the hydraulic oil is lower than the temperature threshold. As a result, the output torque of the internal combustion engine can be made sufficiently larger than the friction torque of the torque converter during idling operation. As a result, even when the vehicle is stopped at a low temperature highland or the like where the intake air amount of the internal combustion engine decreases and the friction torque of the torque converter increases, when the shift lever is switched from the non-driving range to the driving range during idling operation, it is possible to suppress the internal combustion engine from stalling.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the vehicles described above, it is preferable to release the wastegate valve in order to suppress noise and vibration when the actual rotational speed increases in response to the closing of the wastegate valve during idle operation of the internal combustion engine. However, since the actual rotational speed of the internal combustion engine fluctuates during idle operation due to combustion variations (combustion variations) between multiple cylinders, releasing the wastegate valve in response to an increase in the actual rotational speed of the internal combustion engine may cause hunting, in which the wastegate is frequently opened and closed.

[0005] Therefore, the primary objective of this disclosure is to effectively suppress the occurrence of hunting, which occurs when torque-up control, which increases the output torque of an internal combustion engine in accordance with atmospheric pressure, is frequently executed and stopped during idle operation of the internal combustion engine. [Means for solving the problem]

[0006] The vehicle control device of this disclosure is a vehicle control device that performs torque-up control to increase the output torque of an internal combustion engine mounted on a vehicle in accordance with atmospheric pressure during idle operation of the internal combustion engine, and performs the torque-up control on the condition that the target idle speed of the internal combustion engine is less than or equal to a predetermined permitted speed, and the difference between the target idle speed and the actual speed of the internal combustion engine is within a predetermined allowable deviation range.

[0007] The vehicle control device of this disclosure performs torque-up control during idle operation of the internal combustion engine, provided that the target idle speed is below a predetermined permitted speed and the difference between the target idle speed and the actual speed of the internal combustion engine is within a predetermined allowable deviation range, thereby increasing the output torque of the internal combustion engine in accordance with atmospheric pressure. In this way, by allowing or denying the execution of torque-up control by comparing the target idle speed and the permitted speed without transient changes while the actual speed of the internal combustion engine is following the target idle speed, it is possible to effectively suppress the occurrence of hunting, where the execution and stopping of torque-up control are frequently repeated in response to fluctuations in the actual speed during idle operation, and to properly execute torque-up control in accordance with atmospheric pressure.

[0008] Furthermore, the internal combustion engine may include at least one of a variable valve timing mechanism and a supercharger, and the torque-up control may increase the output torque of the internal combustion engine by advancing the opening timing of the intake valve and closing the wastegate valve of the supercharger. This makes it possible to ensure a good amount of intake air during idle operation of the internal combustion engine and increase the output torque of the internal combustion engine, even when the atmospheric pressure around the vehicle is low.

[0009] Furthermore, the internal combustion engine may include a supercharger, and the permitted operating speed may be set to keep the noise emitted from the supercharger during idle operation of the internal combustion engine within an acceptable range. This makes it possible to suppress the discomfort caused to the vehicle occupants by noise from the supercharger when torque-up control is performed during idle operation.

[0010] Furthermore, the control device may perform the torque-up control on the condition that the required torque for the internal combustion engine is greater than or equal to a torque threshold that is set to be smaller as the atmospheric pressure decreases and as the target idle speed decreases. This makes it possible to perform the torque-up control appropriately without excess or deficiency.

[0011] Furthermore, the vehicle may include a generator capable of generating electricity using at least a portion of the power from the internal combustion engine, and a battery that can be charged by the electricity from the generator.

[0012] In other words, the control device of this disclosure can effectively suppress the occurrence of the hunting described above while appropriately performing torque-up control in accordance with atmospheric pressure, so that the battery can be properly charged with electricity from a generator that generates electricity using at least a portion of the power from the internal combustion engine during idle operation. Furthermore, the vehicle to which the control device of this disclosure is applied may be a hybrid vehicle that includes a motor generator as the generator, which can charge a high-voltage battery with electricity generated using at least a portion of the power from the internal combustion engine and also output power for driving, or it may be a vehicle that includes an alternator that can charge an auxiliary battery with electricity generated using at least a portion of the power from the internal combustion engine. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic diagram showing an example of a vehicle including the control device of the vehicle described herein. [Figure 2] This flowchart shows the routines executed by the control system of the vehicle of this disclosure. [Figure 3] This is a schematic diagram showing other vehicles to which the vehicle control system of this disclosure may be applied. [Modes for carrying out the invention]

[0014] Next, with reference to the drawings, embodiments for carrying out the invention of this disclosure will be described.

[0015] Figure 1 is a schematic diagram showing a vehicle 1 including the control device of the present disclosure. The vehicle 1 shown in the figure is a hybrid electric vehicle (HEV) including an engine (internal combustion engine) 2, a motor generator (electric motor) MG, a transmission 3, a clutch K0 and WSC, a battery (high-voltage battery) 4, a power control unit (hereinafter referred to as "PCU") 5 that drives the motor generator MG, and hydraulic control devices 6 and 7. Furthermore, the vehicle 1 includes an engine electronic control unit (hereinafter referred to as "EGECU") 20 as the control device of the present disclosure that controls the engine 2, a transmission electronic control unit (hereinafter referred to as "TMECU") 30 that controls the transmission 3, a motor electronic control unit (hereinafter referred to as "MGECU") 50 that controls the PCU 5, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 100. The HVECU 100 exchanges information with the EGECU 20, TMECU 30 and MGECU 50 to comprehensively control the vehicle 1.

[0016] Engine 2 is a multi-cylinder gasoline engine that converts the reciprocating motion of pistons resulting from the combustion of a mixture of gasoline (hydrocarbon fuel) and air in multiple combustion chambers (cylinders) into rotational motion of a crankshaft (output shaft) CS. However, Engine 2 may be a diesel engine or an LPG engine, etc. Engine 2 includes an electronically controlled throttle valve, multiple intake valves and exhaust valves, a variable valve timing (VVT) mechanism that changes the opening timing and lift amount of the intake and exhaust valves, multiple fuel injectors, multiple spark plugs, an exhaust gas purification device, a supercharger (TC) that compresses intake air using the energy of the exhaust gas, and an intercooler that cools the air compressed by the supercharger (TC).

[0017] In this embodiment, the supercharger TC is a turbocharger and includes a turbine wheel Wt rotatably disposed in a turbine housing formed in the exhaust pipe of the engine 2, a compressor wheel Wc rotatably disposed in a compressor housing formed in the intake pipe of the engine 2, a turbine shaft St integrally connecting the turbine wheel Wt and the compressor wheel Wc, a wastegate valve WGV, and an air bypass valve ABV. The crankshaft CS of the engine 2 is connected to an input member of a damper mechanism D (e.g., a flywheel damper), as shown in the figure.

[0018] The motor-generator MG is a synchronous regenerative motor (three-phase AC motor) that includes a rotor with embedded permanent magnets and a stator around which three-phase coils are wound, and exchanges power with the battery 4 via the PCU 5. The motor-generator MG operates as an electric motor that generates driving torque when powered by the battery 4, and also outputs regenerative braking torque when braking the vehicle 1. In addition, the motor-generator MG also operates as a generator that generates electricity using at least a portion of the power from the engine 2. As shown in Figure 1, the rotor of the motor-generator MG is fixed to the rotor shaft RS.

[0019] The transmission 3 is a multi-speed transmission, for example, a 4-speed to 10-speed transmission, including an input shaft 3i, an output shaft 3o, multiple planetary gears, and multiple clutches and brakes (shifting engagement elements) for each. The transmission 3 shifts the power transmitted to the input shaft 3i in multiple stages and outputs it from the output shaft 3o to the left and right wheels (rear wheels) W via the differential gear DF ​​and drive shaft DS. The clutches and brakes of the transmission 3 are hydraulic engagement elements driven by hydraulic pressure supplied from the hydraulic control device 6.

[0020] Clutch K0 connects the output member of the damper mechanism D, i.e., the crankshaft CS of the engine 2, and the rotor shaft RS, i.e., the rotor of the motor generator MG, and releases the connection between the two. When clutch K0 engages, the engine 2 (crankshaft CS) is connected to the motor generator MG via the clutch K0. Clutch WSC connects the rotor shaft RS, i.e., the rotor of the motor generator MG, and the input shaft 3i of the transmission 3, and releases the connection between the two. When clutch WSC engages, the motor generator MG is connected to the transmission 3 via the clutch WSC.

[0021] That is, in the vehicle 1, the engine 2 is connected to the left and right wheels W via the damper mechanism D, clutch K0, rotor shaft RS (motor generator MG), clutch WSC, transmission 3, differential gear DF, etc. In this embodiment, clutches K0 and WSC are, for example, normally open multi-plate hydraulic clutches driven by hydraulic pressure supplied from a hydraulic control device 7 different from the hydraulic control device 6. Note that clutches K0 and WSC may be arranged inside the rotor of the motor generator MG.

[0022] The battery 4 is, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery having a rated output voltage of about 200 - 800V. However, the battery 4 may be a capacitor, or may include both a secondary battery and a capacitor. The PCU 5 includes an inverter that drives the motor generator MG, a boost converter, a DC / DC converter, etc. (all not shown), and is connected to the battery 4 via the system main relay SMR. The inverter includes, for example, six transistors as switching elements and six diodes connected in parallel in the reverse direction to these transistors. The boost converter boosts the voltage from the battery 4 and supplies it to the inverter, and also降压 the voltage from the inverter and supplies it to the battery 4. The DC / DC converter降压 the power from the battery 4 or the inverter and supplies it to the auxiliary battery and various auxiliary devices (all not shown).

[0023] The hydraulic control devices 6 and 7 each include a valve body in which a plurality of oil passages are formed, a plurality of regulator valves, a plurality of linear solenoid valves, and the like. The hydraulic control device 6 regulates the hydraulic oil (hydraulic pressure) from an electric oil pump (not shown) and supplies it to the clutches and brakes of the transmission 3. The hydraulic control device 7 regulates the hydraulic oil (hydraulic pressure) from the electric oil pump and supplies it to the clutches K0 and WSC. However, the clutches and brakes of the transmission 3, and the clutches K0 and WSC may be driven by a single hydraulic control device.

[0024] The EGECU 20 that controls the engine 2 includes a microcomputer having a CPU, ROM, RAM, input / output interfaces, etc. not shown, various drive circuits, various logic ICs, and the like. Further, the EGECU 20 acquires the detection values of various sensors such as a crank angle sensor, an air flow meter, a throttle opening sensor, an air-fuel ratio sensor, a water temperature sensor, an atmospheric pressure sensor 25 that detects the atmospheric pressure Pa, an accelerator pedal position sensor, and a vehicle speed sensor, and receives a command signal etc. from the HVECU 100. Furthermore, the EGECU 20 calculates the rotational speed Ne of the engine 2 (crankshaft CS) based on the detection value of the crank angle sensor, and calculates the load factor KL based on the rotational speed Ne of the engine 2 and the intake air amount detected by the air flow meter. Then, the EGECU 20 controls a throttle valve, a variable valve mechanism VVT, a fuel injection valve, a spark plug, etc. based on the detection values of various sensors, the calculated values such as the rotational speed Ne, and the command signal etc. from the HVECU 100.

[0025] The TMECU30 includes a microcomputer with a CPU, ROM, RAM, input / output interfaces, etc. (not shown), various drive circuits, various logic ICs, etc. The TMECU30 also acquires detection values ​​from various sensors (all not shown), such as a shift position sensor, an accelerator pedal position sensor, an input rotation speed sensor that detects the rotation speed of the input shaft 3i, an output rotation speed sensor that detects the rotation speed of the output shaft 3o, and a vehicle speed sensor, and receives command signals from the HVECU100. The TMECU30 controls the transmission 3, or hydraulic control device 6, based on the detection values ​​from the various sensors and command signals from the HVECU100.

[0026] The MGECU50 includes a microcomputer with a CPU, ROM, RAM, input / output interfaces, etc. (not shown), various drive circuits, various logic ICs, etc. The MGECU50 acquires the pre-boost and post-boost voltages of the boost converter, the rotational position of the rotor (rotor shaft RS) of the motor generator MG detected by a rotational position sensor (resolver) (not shown), the phase current applied to the motor generator MG, etc., and also receives command signals from the HVECU100. The MGECU50 switches and controls the inverter and boost converter based on these detected values ​​and command signals from the HVECU100.

[0027] The HVECU100 includes a microcomputer with a CPU, ROM, RAM, input / output interfaces, etc. (not shown), various drive circuits, various logic ICs, etc. The HVECU100 acquires signals from the start switch (IG switch), accelerator pedal position Acc (amount of accelerator pedal depression) detected by the accelerator pedal position sensor, vehicle speed V detected by the vehicle speed sensor, gear γ of the transmission 3 corresponding to accelerator pedal position Acc and vehicle speed V, and rotational speed Nm of the motor generator MG from the MGECU50. Furthermore, the HVECU100 acquires the State of Charge (SOC) of the battery 4 calculated by the power management device (power management ECU) (not shown), target charge / discharge power Pb* based on the SOC, allowable charge power Win, allowable discharge power Wout, etc. from the power management device (power management ECU) (not shown). When vehicle 1 is in motion, the HVECU 100 sets the required torque Te* for engine 2, the torque command value Tm* for motor generator MG, the command value for transmission 3 (hydraulic control device 6), etc., based on the accelerator opening Acc and vehicle speed V, and controls the clutch K0 and WSC, i.e., the hydraulic control device 7.

[0028] Furthermore, while vehicle 1 is stopped, HVECU100 determines whether or not it is necessary to charge battery 4 based on the SOC calculated by the power management device. If it is necessary to charge battery 4, HVECU100 puts engine 2 into idle operation and causes motor generator MG to generate electricity using at least a portion of the power from engine 2 in idle operation, and charges battery 4 with the electricity generated by motor generator MG. In this case, HVECU100 sets the target idle speed Ne* of engine 2, the required torque Te* for engine 2, and the torque command value Tm* for motor generator MG at predetermined intervals (minute intervals) based on the SOC of battery 4. In addition, HVECU100 transmits the target idle speed Ne* and the required torque Te* to EGECU20, and transmits the torque command value Tm* to MGECU50. The EGECU20 controls the engine 2 so that it outputs torque corresponding to the requested torque Te* and the crankshaft CS rotates at the target idle speed Ne*, while the MGECU50 controls the PCU5 based on the torque command value Tm*. In addition, the EGECU20 performs torque-up control to increase the output torque of the engine 2 as needed during idle operation. In this embodiment, the torque-up control advances the opening timing of the intake valve using the variable valve timing mechanism (VVT) and closes the wastegate valve WGV of the supercharger TC.

[0029] Figure 2 is a flowchart showing a routine that is repeatedly executed by the EGECU20 at predetermined time intervals (minute intervals) to determine whether torque-up control is necessary during idle operation of engine 2.

[0030] When the execution timing for the routine in Figure 2 arrives, the EGECU20 obtains the separately calculated rotational speed Ne of the engine 2, the target idle rotational speed Ne* and required torque Te* from the HVECU100, the vehicle speed V from the vehicle speed sensor, and the atmospheric pressure Pa from the atmospheric pressure sensor 25 (step S100). Next, the EGECU20 determines whether the target idle rotational speed Ne* obtained in step S100 is less than or equal to a predetermined execution permission rotational speed Nref (step S110). The execution permission rotational speed Nref, used as a threshold in step S110, is determined through experiments and analyses to keep the noise emitted from the supercharger TC with the wastegate valve WGV closed during idle operation of the engine 2 within an acceptable range, and is set to a value of approximately 900-1000 rpm, for example. If the target idle speed Ne* exceeds the permitted execution speed Nref (step S110: NO), the EGECU20 turns off the torque-up control flag (step S115) to prohibit the execution of torque-up control from the standpoint of suppressing noise from the supercharger TC, and terminates the routine shown in Figure 2.

[0031] If the target idle speed Ne* is less than or equal to the permitted rotational speed Nref (step S110: YES), the EGECU20 determines whether the absolute value |ΔNe| of the difference ΔNe between the target idle speed Ne* obtained in step S100 and the rotational speed Ne corresponding to the actual rotational speed of the engine 2 is less than or equal to a predetermined allowable rotational speed difference ΔNref, that is, whether the difference ΔNe between the target idle speed Ne* and the rotational speed Ne is within a predetermined allowable deviation range (the range from -ΔNref to ΔNref) (step S120). In this embodiment, the allowable rotational speed difference ΔNref used in step S120 is set to a value of, for example, about 20-50 rpm. If the absolute value |ΔNe| of the difference ΔNe between the target idle speed Ne* and the actual speed Ne exceeds the allowable speed difference ΔNref, and the difference ΔNe is not within the allowable deviation range (step S120: NO), the EGECU20 considers that the actual speed's ability to follow (converge) the target idle speed Ne* is insufficient, and in order to prohibit the execution of torque-up control, it turns off the torque-up control flag (step S115) and terminates the routine shown in Figure 2.

[0032] On the other hand, if the difference ΔNe between the target idle speed Ne* and the rotation speed (actual rotation speed) Ne falls within the above-mentioned allowable deviation range (step S120: YES), the EGECU20 increments counter C (step S130) and determines whether counter C is greater than or equal to a predetermined threshold Cref (step S140). In this embodiment, the threshold Cref used in step S140 is set such that the product of the execution period of the routine in Figure 2 and the threshold Cref is, for example, about 1 second. If counter C is less than the threshold Cref (step S140: NO), the EGECU20 turns off the torque-up control flag (step S115) to prohibit the execution of torque-up control and terminates the routine in Figure 2.

[0033] Furthermore, if counter C exceeds the threshold Cref (step S140: YES), EGECU20 sets the torque threshold Tref based on the atmospheric pressure Pa and target idle speed Ne* acquired in step S100 (step S150). In step S150, EGECU20 derives the torque threshold Tref corresponding to the atmospheric pressure Pa and target idle speed Ne* acquired in step S100 from a pre-created torque threshold setting map (not shown). The torque threshold setting map is created through experimentation and analysis to define the correlation between the atmospheric pressure Pa and target idle speed Ne* around the vehicle 1 and the required torque for the engine 2 when it is necessary to stabilize the engine speed Ne of the idled engine 2 by torque-up control, and is stored in a ROM (not shown) of EGECU20. In this embodiment, the torque threshold setting map is created to set the torque threshold Tref to be smaller as atmospheric pressure Pa decreases and as the target idle speed Ne* decreases.

[0034] After setting the torque threshold Tref, EGECU20 determines whether the requested torque Te* obtained in step S100 is greater than or equal to the torque threshold Tref (step S160). If the requested torque Te* is less than the torque threshold Tref (step S160: NO), EGECU20 considers that torque-up control is unnecessary and turns off the torque-up control flag to prohibit the execution of torque-up control (step S115), and terminates the routine shown in Figure 2. If the requested torque Te* is greater than or equal to the torque threshold Tref (step S160: YES), EGECU20 determines whether the vehicle speed V obtained in step S100 is less than a predetermined vehicle speed threshold Vref (step S170). The vehicle speed threshold Vref used in step S170 is used to determine whether vehicle 1 is stopped, and is, for example, a vehicle speed of about 2-3 km / h.

[0035] If the vehicle speed V obtained in step S100 is greater than or equal to the vehicle speed threshold Vref (step S170: NO), the EGECU20 considers that vehicle 1 has started moving and turns off the torque-up control flag (step S115) to prohibit the execution of torque-up control, and terminates the routine in Figure 2. On the other hand, if the vehicle speed V obtained in step S100 is less than the vehicle speed threshold Vref (step S170: YES), the EGECU20 considers that vehicle 1 is stopped and turns on the torque-up control flag (step S180) to allow the execution of torque-up control, and terminates the routine in Figure 2. While the torque-up control flag is turned on in step S180, the EGECU20 executes torque-up control, advancing the opening timing of the intake valve by a predetermined amount using the variable valve timing mechanism (VVT), and closing the wastegate valve WGV of the supercharger TC. As a result, even when the atmospheric pressure Pa around vehicle 1 is low, a sufficient amount of intake air can be secured during idle operation of engine 2, thereby increasing the output torque of engine 2. Consequently, in vehicle 1, while engine 2 is idle, the actual rotational speed of engine 2 can be stabilized, and the battery 4 can be charged with electricity generated by the motor generator MG.

[0036] As described above, the EGECU20, the control device of vehicle 1, executes torque-up control to increase the output torque of engine 2 in accordance with atmospheric pressure Pa during idle operation of engine 2, provided that the target idle speed Ne* is less than or equal to a predetermined permitted execution speed Nref (step S110: YES) and the difference ΔN between the target idle speed Ne* and the rotational speed (actual rotational speed) Ne is within a predetermined allowable deviation range (range from -ΔNref to ΔNref) (step S120: YES). In this way, while the rotational speed Ne of engine 2 is following (converging) the target idle speed Ne*, the torque-up control is permitted or denied by comparing the target idle speed Ne* and the permitted execution speed Nref without transient changes, thereby effectively suppressing the occurrence of hunting, where the execution and stopping of torque-up control is frequently repeated in response to fluctuations in the rotational speed Ne during idle operation, and enabling the torque-up control to be properly executed in accordance with atmospheric pressure Pa. As a result, it becomes possible to stabilize the rotational speed Ne of the engine 2, which is running at idle, while charging the battery 4 with electricity generated by the motor generator MG.

[0037] Furthermore, in vehicle 1, engine 2 includes a variable valve timing mechanism (VVT) and a supercharger (TC), and torque-up control increases the output torque of engine 2 by advancing the opening timing of the intake valves using the variable valve timing mechanism (VVT) and closing the wastegate valve (WGV) of the supercharger (TC). This makes it possible to ensure a good intake air volume during idle operation of engine 2 and increase the output torque of engine 2, even when the atmospheric pressure Pa around vehicle 1 is low. However, engine 2 does not necessarily need to include both the variable valve timing mechanism (VVT) and the supercharger (TC); it is sufficient if it includes at least one of the two.

[0038] Furthermore, in vehicle 1, the permitted operating speed Nref used as a threshold in step S110 is set to a value that keeps the noise emitted from the supercharger TC with the wastegate valve WGV closed during idle operation of engine 2 within an acceptable range. This makes it possible to suppress the discomfort caused to the occupants of vehicle 1 by the noise from the supercharger TC when torque-up control is performed during idle operation.

[0039] Furthermore, the EGECU20 performs torque-up control on the condition that the required torque Te* for engine 2 is greater than or equal to the torque threshold Tref, which is set to be smaller as atmospheric pressure Pa decreases and as the target idle speed Ne* decreases (step S160: YES). This makes it possible to perform torque-up control appropriately without excessive or insufficient control.

[0040] In addition, in the above vehicle 1, the clutch WSC may be omitted, and the input shaft 3i of the transmission 3 may be connected to the rotor shaft RS of the motor generator MG via a lock-up clutch and torque converter. Furthermore, as shown in Figure 1, the vehicle 1 may be a rear-wheel drive vehicle, a front-wheel drive vehicle, or a four-wheel drive vehicle that includes a transfer or other motor generator for driving wheels other than the wheels W (front wheels) not shown. Moreover, the EGECU 20 control device of this disclosure may be applied to a series hybrid vehicle, as long as it includes a motor generator MG capable of generating electricity using at least a portion of the power from the engine 2 and a battery (high-voltage battery) 4 that can be charged by the power from the motor generator MG.

[0041] Furthermore, the EGECU 20 control device of this disclosure may be applied to a vehicle 1B that includes only an engine 2 as a power source for driving, as shown in Figure 3. As shown in the figure, the engine 2 of the vehicle 1B includes a starter 11 that outputs cranking torque to the crankshaft CS to start the engine 2, and an alternator 12 that is driven by the engine 2 to generate electricity. In addition, the vehicle 1B includes an auxiliary battery 40, such as a lead-acid battery having a rated output voltage of about 12-14V. The auxiliary battery 40 is charged by power from the alternator 12 and supplies power to various auxiliary components of the engine 2, including the starter 11, and on-board electrical equipment.

[0042] In addition, in vehicle 1B, the input shaft 3i of the transmission 3 is connected to the crankshaft CS of the engine 2 via a starting device 8. The starting device 8 is a torque converter with a torque amplification function and includes a lock-up clutch 8c and a damper mechanism 8d. In such vehicle 1B, by executing the routine in Figure 2, the occurrence of the hunting described above can be suppressed well, and torque-up control can be properly executed according to the atmospheric pressure Pa, so that the auxiliary battery 40 can be properly charged with electricity from the alternator 12 driven and generated by the engine 2 during idle operation. Note that the transmission 3 is not limited to a multi-stage transmission including multiple planetary gears and multiple clutches and brakes, but may also be a mechanical continuously variable transmission (CVT) or a dual-clutch transmission.

[0043] Furthermore, the invention disclosed herein is not limited in any way to the embodiments described above, and it goes without saying that various modifications can be made within the scope of this disclosure. Moreover, the embodiments described above are merely one specific form of the invention described in the summary of the invention, and do not limit the elements of the invention described in the summary of the invention. [Industrial applicability]

[0044] The invention disclosed herein can be used in the vehicle manufacturing industry and the like. [Explanation of symbols]

[0045] 1,1B Vehicle, 2 Engine, 3 Transmission, 4 Battery, 40 Auxiliary Battery, 5 Power Control Unit (PCU), 6,7 Hydraulic Control Unit, 8 Launching Device, 11 Starter, 12 Alternator, 20 Engine Electronic Control Unit (EGECU), 25 Atmospheric Pressure Sensor, 30 Transmission Electronic Control Unit (TMECU), 50 Motor Electronic Control Unit (MGECU), 100 Hybrid Electronic Control Unit (HVECU), MG Motor Generator, TC Supercharger, VVT Variable Valve Timing, WGV Wastegate Valve.

Claims

1. A vehicle control device that performs torque-up control to increase the output torque of an internal combustion engine mounted on a vehicle in accordance with atmospheric pressure during idle operation of the internal combustion engine, A vehicle control device that performs the torque-up control, provided that at least the target idle speed of the internal combustion engine is less than or equal to a predetermined permitted rotational speed, and the difference between the target idle speed and the actual rotational speed of the internal combustion engine falls within a predetermined allowable deviation range.

2. In the vehicle control device according to claim 1, The internal combustion engine includes at least one of a variable valve timing mechanism and a supercharger. The torque-up control is a vehicle control device that increases the output torque of the internal combustion engine by advancing the opening timing of the intake valve and closing the wastegate valve of the supercharger, by at least one of the two.

3. In the vehicle control device according to claim 2, The internal combustion engine includes the supercharger, The aforementioned permitted rotational speed is determined to keep the noise emitted from the supercharger during idle operation of the internal combustion engine within an acceptable range for a vehicle control device.

4. In the vehicle control device according to claim 3, A vehicle control device that performs the torque-up control on the condition that the required torque for the internal combustion engine is greater than or equal to a torque threshold that is set to be smaller as the atmospheric pressure decreases and as the target idle speed decreases.

5. In a vehicle control device according to any one of claims 1 to 4, The vehicle includes a control device for the vehicle, which includes a generator capable of generating electricity using at least a portion of the power from the internal combustion engine, and a battery that can be charged by the electricity from the generator.

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