Vehicle control devices

Abstract

To make both suppression of vibration and attainment of torque responsiveness in accordance with a running mode compatible.SOLUTION: A vehicular control device is used in a vehicle provided with at least one power source that outputs power to a driving shaft connected to an axle, controls the power source so that the vehicle runs in one running mode selected out of a plurality of running modes, and also controls the power source so that torque outputted to the driving shaft when an accelerator is turned off gradually decreases over a target decreasing-time toward torque which is required when the accelerator is turned off. The vehicular control device sets the target decreasing-time so that the time is equal to n-times a reciprocal of resonant frequency of a driving system including the driving source, where n is an integer being one or more and is changed depending on the running mode.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a control device for a vehicle. [Background Art]

[0002] Conventionally, as this type of vehicle control device, one used in a vehicle including at least one power source that outputs driving power for traveling has been proposed (see, for example, Patent Document 1). In this device, the time for changing the magnitude of torque output by the drive source is set to the reciprocal of the lowest resonance frequency among the resonance frequencies of a plurality of resonant members in the transmission path from the power source to the vehicle body. This suppresses vehicle vibration. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2019-99059 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] By the way, in general, in a vehicle control device, when the accelerator is off, control is performed to gradually decrease the torque output to the drive shaft from positive driving torque toward negative required torque (braking torque) at accelerator off. In this control, when the torque output to the drive shaft changes from positive torque to negative torque, vibration may occur due to torsion of the drive shaft. In order to suppress such vibration, it is conceivable to reduce the rate at which the torque output to the drive shaft is changed, thereby suppressing torsion of the drive shaft to suppress vibration. However, in this case, since the torque output to the drive shaft changes slowly, torque responsiveness deteriorates. In particular, in a vehicle control device that controls a power source such that the vehicle travels in one travel mode selected from among a plurality of modes, desired torque responsiveness may not be obtained depending on the travel mode.

[0005] The vehicle control device disclosed herein primarily aims to achieve both vibration suppression and torque responsiveness according to the driving mode. [Means for solving the problem]

[0006] The vehicle control device of this disclosure employs the following means to achieve the main objective described above.

[0007] The vehicle control device disclosed herein is A vehicle control device used in a vehicle equipped with at least one power source that outputs power to a drive shaft connected to an axle, which controls the power source so that the vehicle runs in one driving mode selected from a plurality of modes, and controls the power source so that when the accelerator is released the torque output to the drive shaft gradually decreases over a target reduction time toward the required torque at the time of accelerator release, The target deceleration time is set to be n times the reciprocal of the resonant frequency of the drive system including the power source. The aforementioned n is an integer with a value of 1 or greater, and is changed according to the driving mode. This is the gist of it.

[0008] In the vehicle control device of this disclosure, the target reduction time is set to be n times the reciprocal of the resonant frequency of the drive system including the power source, where n is an integer of 1 or greater and is changed according to the driving mode. By setting n to an integer of 1 or greater, vibration can be suppressed. Furthermore, by changing n according to the driving mode, the torque output from the power source when the accelerator is released can be gradually reduced according to the target reduction time according to the driving mode. This makes it possible to achieve torque responsiveness according to the driving mode. As a result, it is possible to achieve both vibration suppression and torque responsiveness according to the driving mode.

[0009] In the vehicle control device of the present invention, the plurality of modes include a first mode and a second mode that places more emphasis on the output responsiveness of the driving torque compared to the first mode, and when the driving mode is the second mode, n may be smaller than when it is the first mode. In this way, when the driving mode is the second mode, the target reduction time can be shortened compared to when it is the first mode, and the torque output to the drive shaft can be reduced more quickly. As a result, torque responsiveness can be improved in the second mode.

[0010] In a vehicle control device according to the present disclosure, in an embodiment in which multiple modes include a first mode and a second mode that places more emphasis on the output responsiveness of the driving torque compared to the first mode, when the driving mode is the second mode, when a predetermined condition is met that prohibits rapidly reducing the torque output to the drive shaft, n may be made larger than when the predetermined condition is not met. In this way, when the predetermined condition is met, the time for reducing the torque output from the power source can be extended. [Brief explanation of the drawing]

[0011] [Figure 1] A diagram showing the general configuration of the hybrid vehicle 20. [Figure 2] A schematic diagram showing the general configuration of engine 22. [Figure 3] A flowchart illustrating an example of a control routine. [Figure 4] An explanatory diagram showing an example of the relationship between vehicle speed V and required torque Tout*. [Figure 5] A flowchart showing the relationship between axial torque (Tax*) and elapsed time (toff). [Modes for carrying out the invention]

[0012] Next, embodiments of the present disclosure will be described. Figure 1 is a schematic diagram showing the configuration of a hybrid vehicle 20 equipped with a vehicle control device as an embodiment of the present disclosure. Figure 2 is a schematic diagram showing the configuration of an engine 22 mounted on the hybrid vehicle 20. The hybrid vehicle 20 of the embodiment includes an engine 22 and a motor 30 as power sources, an inverter 32, a clutch K0, an automatic transmission 40, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70.

[0013] Engine 22, configured as an internal combustion engine using gasoline as fuel, has, as shown in Figure 2, a port injection valve 126 that injects fuel into the intake port and an in-cylinder injection valve 127 that injects fuel into the cylinder, and operates in one of three modes: port injection mode, in-cylinder injection mode, or shared injection mode. In port injection mode, air from the air cleaner 122 is drawn into the intake manifold 123, passes through the throttle valve 124 and surge tank 125, and fuel is injected from the port injection valve 126 downstream of the surge tank 125 in the intake manifold 123 to mix the air and fuel. This mixture is drawn into the combustion chamber 129 via the intake valve 128, and is combusted by an electric spark from the spark plug 130, converting the reciprocating motion of the piston 132, which is pushed down by the energy within the cylinder bore, into the rotational motion of the crankshaft 23. In the in-cylinder injection mode, air is drawn into the combustion chamber 129, fuel is injected from the in-cylinder injection valve 127 during the intake and compression strokes, and the fuel is combusted by an electric spark from the spark plug 130 to obtain rotational motion of the crankshaft 23. In the shared injection mode, fuel injection from the port injection valve 126 and fuel injection from the in-cylinder injection valve 127 are shared. The exhaust gas discharged from the combustion chamber 129 to the exhaust pipe 134 via the exhaust valve 133 is discharged through an exhaust system that includes a purification device 135 and a gasoline particulate filter (GPF) 136. The purification device 135 has a purification catalyst (three-way catalyst) 135a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in the exhaust gas. The GPF 136 is formed as a porous filter using ceramics or stainless steel, and collects particulate matter (PM) such as soot in the exhaust gas. Alternatively, a four-way catalyst combining the purification function of a three-way catalyst with the particulate matter collection function may be used instead of GPF136.

[0014] The engine 22 is controlled by an electronic engine control unit (hereinafter referred to as "engine ECU") 24. The engine ECU 24 receives, for example, the crank angle θcr from a crank position sensor 140 that detects the rotational position of the crankshaft 23 of the engine 22, and the coolant temperature Tw from a water temperature sensor 142 that detects the temperature of the coolant in the engine 22. The engine ECU24 also receives input from the cam position sensor 144, which detects the rotational position of the intake camshaft that opens and closes the intake valve 128 and the rotational position of the exhaust camshaft that opens and closes the exhaust valve 133, the throttle opening TH from the throttle valve position sensor 124a, which detects the position of the throttle valve 124, the intake air volume Qa from the airflow meter 123a installed upstream of the throttle valve 124 in the intake manifold 123, the intake air temperature Ta from the temperature sensor 123t installed upstream of the throttle valve 124 in the intake manifold 123, and the surge pressure Ps from the pressure sensor 125a installed in the surge tank 125. Furthermore, the engine ECU24 also receives input from the catalyst temperature Tcat from the temperature sensor 135b which detects the temperature of the purification catalyst 135a, the front air-fuel ratio AF1 from the front air-fuel ratio sensor 137 which is installed upstream of the purification device 135 in the exhaust pipe 134, the rear air-fuel ratio AF2 from the rear air-fuel ratio sensor 138 which is installed between the purification device 135 and the GPF136 in the exhaust pipe 134, and the differential pressure ΔP from the differential pressure sensor 136a which detects the differential pressure before and after the GPF136 (the differential pressure between the upstream and downstream sides).

[0015] The engine ECU24 outputs, for example, control signals to the throttle valve 124, the port injection valve 126, the in-cylinder injection valve 127, and the spark plug 130.

[0016] An engine ECU 24 calculates the rotational speed Ne of an engine 22 based on the crank angle θcr of the engine 22 from a crank position sensor 140. The engine ECU 24 also calculates a load factor KL, which is the ratio of the volume of air actually drawn in during one cycle to the stroke volume per cycle of the engine 22, based on the intake air amount Qa from an air flow meter 123a and the rotational speed Ne of the engine 22.

[0017] A motor 30 is configured as a synchronous generator-motor. A rotating shaft 31, to which a rotor of the motor 30 is fixed, is connected to a crankshaft 23 of the engine 22 via a clutch K0, and is also connected to an input shaft 41 of an automatic transmission 40. An inverter 32 is used for driving the motor 30 and is connected to a power line 61. The motor 30 is rotationally driven when a plurality of switching elements of the inverter 32 are switching-controlled by a motor electronic control unit (hereinafter referred to as "motor ECU") 34. The motor ECU 34 inputs the rotational position θmg from a rotational position sensor 30a that detects the rotational position of the rotor (rotating shaft 31) of the motor 30, the phase currents Iu and Iv from current sensors that detect the phase current of each phase of the motor 30, and the like, and outputs control signals and the like to the inverter 32. The motor ECU 34 calculates the rotational speed Nmg of the motor 30 based on the rotational position θmg of the rotor (rotating shaft 31) of the motor 30 from the rotational position sensor 30a.

[0018] The clutch K0 is configured, for example, as a hydraulically driven friction clutch, and is controlled by an HVECU 70 to connect and disconnect the connection between the crankshaft 23 of the engine 22 and the rotating shaft 31 of the motor 30.

[0019] The automatic transmission 40 includes a torque converter 43 and, for example, a 6-speed automatic transmission 45. The torque converter 43 is configured as a general fluid transmission device and transmits power from the input shaft 41 connected to the rotating shaft 31 of the motor 30 to the transmission input shaft 44, which is the input shaft of the automatic transmission 45, with amplified torque, or transmits the torque directly without amplification. The automatic transmission 45 includes the transmission input shaft 44, an output shaft 42 connected to the drive wheel 49 via a differential gear 48, a plurality of planetary gears, and a plurality of hydraulically driven friction engagement elements (clutch, brake). The automatic transmission 45 transmits power between the transmission input shaft 44 and the output shaft 42 by engaging and disengaging the plurality of friction engagement elements to form forward and reverse gears from the 1st to the 6th gear. The clutch K0 and automatic transmission 45 are supplied with hydraulic fluid from a mechanical oil pump or electric oil pump, with the hydraulic pressure regulated by a hydraulic control device (not shown).

[0020] The battery 60 is configured as, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery with a rated voltage of several hundred volts, and is connected to the power line 61 together with the inverter 32.

[0021] The HVECU 70 is configured as a microcomputer. The HVECU 70 receives, for example, the rotational speed Nin from a rotational speed sensor 41a attached to an input shaft 41 of an automatic transmission 40, the rotational speed Nmi from a rotational speed sensor 44a attached to a transmission input shaft 44 of the automatic transmission 40, and the rotational speed Nout from a rotational speed sensor 42a attached to an output shaft 42 of the automatic transmission 40 as inputs. The HVECU 70 also receives, as inputs, the voltage Vb of a battery 60 from a voltage sensor attached between terminals of the battery 60, and the current Ib of the battery 60 from a current sensor attached to an output terminal of the battery 60 (the value is positive when discharging from the battery 60). Furthermore, the HVECU 70 also receives, as inputs, an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects an operation position of a shift lever 81, an accelerator opening Acc from an accelerator pedal position sensor 84 that detects a depression amount of an accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 that detects a depression amount of a brake pedal 85, and a vehicle speed V from a vehicle speed sensor 87. An operation signal from a mode switch 88 can also be cited as an input. The mode switch 88 is a switch for, every time it is operated by a driver, instructing toggle-style switching of a travel mode in the order of a normal mode, a sports mode, and an eco mode. The sports mode (a second mode) is a mode that emphasizes output responsiveness of driving torque compared to the normal mode and the eco mode (a first mode). The eco mode is a mode that emphasizes energy efficiency compared to the normal mode and the sports mode.

[0022] The HVECU 70 outputs various control signals via an output port. For example, control signals to the clutch K0 and the automatic transmission 40 (hydraulic control device) can be mentioned. The HVECU 70 is connected to an engine ECU 24 and a motor ECU 34 via a communication port. The HVECU 70 calculates a state of charge SOC of the battery 60 and input / output limits Win and Wout, which are allowable maximum powers that can be input / output to / from the battery 60, based on the voltage Vb and the current Ib of the battery 60.

[0023] In the hybrid vehicle 20 of this embodiment, the HVECU 70, engine ECU 24, and motor ECU 34 coordinately control the engine 22, clutch K0, motor 30, and automatic transmission 40 so that the vehicle can run in hybrid driving mode (HV driving mode) or electric driving mode (EV driving mode).

[0024] In controlling the engine 22 and motor 30 in HV driving mode, the HVECU 70 first sets the required torque Tout* (a positive value is driving torque, and a negative value is braking torque) on the output shaft 42 as the drive shaft based on the accelerator opening Acc and vehicle speed V. Next, it sets the required torque Tin* of the input shaft 41 by dividing the required torque Tout* of the output shaft 42 by the rotational speed ratio Gt of the automatic transmission 40. Then, while charging and discharging the battery 60 within the range of input / output limits Win and Wout, it sets the target torque Te* of the engine 22 and the torque command Tm* of the motor 30 so that the required torque Tin* is output to the input shaft 41, and transmits the target torque Te* to the engine ECU 24 and the torque command Tm* to the motor ECU 34. The engine ECU 24 calculates the required load factor KL* from the target torque Te* and controls the operation of the engine 22 (such as intake air volume control, fuel injection control, and ignition control) so that the engine 22 operates at the target torque Te*. In ignition control, the engine ECU 24 sets the ignition timing of the engine 22 to the efficiency ignition timing Tfref for efficient operation of the engine 22. The motor ECU 34 controls the switching of multiple switching elements of the inverter 32 so that the motor 30 is driven by the torque command Tm*.

[0025] In controlling the engine 22 and motor 30 in EV driving mode, the HVECU 70 first sets the required torque Tout* in the same manner as in HV driving mode. Next, it sets the required torque Tin* of the input shaft 41 to the value obtained by dividing the required torque Tout* of the output shaft 42 by the rotational speed ratio Gt of the automatic transmission 40. Then, it sets the torque command Tm* of the motor 30 so that the battery 60 is charged and discharged within the range of input / output limits Win and Wout as the required torque Tin* is output to the input shaft 41, and sends a stop command for the engine 22 to the engine ECU 24 and the torque command Tm* to the motor ECU 34. The engine ECU 24 stops the engine 22. The motor ECU 34 controls the switching of multiple switching elements of the inverter 32 so that the motor 30 is driven by the torque command Tm*.

[0026] In the hybrid vehicle 20 of this embodiment, the engine ECU 24 performs ignition retardation control, which delays the ignition timing of the engine 22 from the efficiency ignition timing Tfref in order to raise the temperature of the purification catalyst 135a in the purification device 135; ignition retardation control, which delays the ignition timing of the engine 22 from the efficiency ignition timing Tfref in order to warm up the GPF 136; and ignition retardation control, which delays the ignition timing of the engine 22 from the efficiency ignition timing Tfref when the engine 22 is idle. Furthermore, when the catalyst temperature Tcat detected by the temperature sensor 135b exceeds the threshold Tcat1, the execution of these ignition retardation controls is prohibited in order to suppress the temperature rise of the purification catalyst 135a. The threshold Tcat1 is a threshold used to determine whether the purification catalyst 135a in the purification device 135 will reach a high temperature if ignition retardation control is executed. When the execution of ignition retardation control is prohibited, the ignition timing of the engine 22 is set to the efficiency ignition timing Tfref.

[0027] Next, the operation of the hybrid vehicle 20 equipped with the vehicle control device of the embodiment configured in this way will be described, in particular, the operation of the engine 22 and motor 30 when the accelerator pedal 83 is turned off. Figure 3 is a flowchart of an example of a control routine executed by the HVECU 70. This routine is executed when the accelerator is turned off. If the accelerator is turned on while this routine is being executed, the execution of this routine is stopped, and the control of the HV driving mode or EV driving mode described above is executed.

[0028] When this routine is executed, the HVECU70 performs the process of inputting the vehicle speed V (S100). The vehicle speed V is the value detected by the vehicle speed sensor 87.

[0029] Next, the required torque Tout* is set based on the input vehicle speed V (S110). Figure 4 is an explanatory diagram showing an example of the relationship between vehicle speed V and required torque Tout* when the accelerator is released. In the figure, the required torque Tout* is set to a positive value for the drive side torque and a negative value for the braking side torque. The required torque Tout* is the torque output to the output shaft 42 when the accelerator is released in a vehicle that runs on power from the engine without a drive motor, that is, a torque that simulates engine braking. As shown in the figure, when the vehicle speed V is less than the threshold Vref, the required torque Tout* is set to a predetermined torque Toref that is greater than the value of 0, and when the vehicle speed V is greater than or equal to the threshold Vref, it is set to be smaller than the value of 0 when the vehicle speed V is high compared to when it is low.

[0030] Next, the driving mode set by the mode switch 88 is checked (S120). When the driving mode is normal mode or eco mode, the coefficient n used when setting the target drop time td in S160 is set to a value of 2 (S140). Then, the target drop time td is set to the reciprocal of the resonant frequency f of the drive system including the engine 22, motor 30 and automatic transmission 40 multiplied by the coefficient n (here, a value of 2) (S160). Then, the elapsed time toff since the accelerator pedal 83 was turned off is input (S170). Next, using the following equation (1), the shaft torque Tax* output to the output shaft 42 is set so that the shaft torque Tax* is gradually reduced toward the required torque Tout* by the target drop time td, within a range that does not fall below the required torque Tout* (S180). In equation (1), "Tout_i" is the required torque Tout* that was set immediately before the accelerator pedal 83 was turned off. Figure 5 is an explanatory diagram showing the relationship between shaft torque Tax* and elapsed time toff. As shown by the dashed line in the figure, the axial torque Tax* decreases toward the required torque Tout* with a reduction time of twice the reciprocal of the resonant frequency f (=1 / f).

[0031] Tax*=max(Tout*,(Tout*-Tout_i) / td·toff+Tout_i) ···(1)

[0032] Once the shaft torque Tax* is set, the engine 22 and motor 30 are controlled so that torque based on the shaft torque Tax* is output to the output shaft 42 while charging and discharging the battery 60 within the range of input / output limits Win and Wout (S190). In this control, the value obtained by dividing the shaft torque Tax* by the rotational speed ratio Gt of the automatic transmission 40 is set as the required torque Tin* of the input shaft 41. Then, the torque command Tm* of the motor 30 is set to the smaller of the required torque Tin* and the output limit Wout, and the larger of the input limit Win. In other words, the torque command Tm* is set to the value obtained by limiting the required torque Tin* by the input / output limits Win and Wout. In HV driving mode, a fuel cut command to stop the fuel supply to the engine 22 is sent to the engine ECU 24, and the torque command Tm* is sent to the motor ECU 34. In EV driving mode, a stop command for the engine 22 is sent to the engine ECU 24, and the torque command Tm* is sent to the motor ECU 34. The engine ECU 24 stops the fuel supply to the engine 22 or stops the operation of the engine 22. The motor ECU 34 controls the switching of multiple switching elements of the inverter 32 so that the motor 30 is driven by the torque command Tm*. In this way, the torque output to the output shaft 42 is reduced over a period of time that is an integer multiple (in this case, 2 times) of the resonant frequency f of the drive system, thereby suppressing vibrations caused by the resonance of the drive system. Then, it is determined whether the shaft torque Tax* has reached the required torque Tout* (S200). If the shaft torque Tax* is not the required torque Tout*, the process returns to S170. If the shaft torque Tax* has reached the required torque Tout*, this routine is terminated.

[0033] When the driving mode in S120 is in sport mode, it is then determined whether a predetermined condition is met that prohibits rapidly reducing the torque output to the output shaft 42 (130). The predetermined condition includes a first and a second condition. The first condition is that the absolute value of the input limit Win (negative value) is smaller than the threshold Winref. The threshold Winref is a threshold for determining whether the absolute value of the input limit Win is small or not. The second condition is that the catalyst temperature Tcat detected by the temperature sensor 135b exceeds the threshold Tcat1, and the execution of the ignition retardation control described above is prohibited, that is, the ignition retardation is prohibited in order to suppress the temperature rise of the purification catalyst 135a. The predetermined condition is considered to be met when at least one of the first and second conditions is met.

[0034] If the predetermined conditions are not met in S130, the coefficient n is set to a value of 1, which is smaller than the coefficient n set in S140 (S150). Then, the target drop time td is set to the reciprocal of the resonant frequency f of the drive system multiplied by the coefficient n (here, a value of 1) (S160). Furthermore, the elapsed time toff is input (S170). Next, using the above equation (1), the shaft torque Tax* is set so that the shaft torque Tax* output to the output shaft 42 gradually decreases toward the required torque Tout* over the target drop time td, within a range that does not fall below the required torque Tout* (S180). Once the shaft torque Tax* is set in this way, the engine 22 and motor 30 are controlled so that the shaft torque Tax* is output to the output shaft 42 (S190), and it is determined whether the shaft torque Tax* is equal to the required torque Tout* (S200). If the shaft torque Tax* is not equal to the required torque Tout*, the process returns to S170. This routine terminates when the shaft torque Tax* is equal to the required torque Tout*. If the predetermined conditions are not met in S130, the shaft torque Tax* decreases toward the required torque Tout* at a rate equal to 1 times the reciprocal of the resonant frequency f (=1 / f), as shown by the solid line in Figure 5. Because it decreases at an integer multiple of the reciprocal of the resonant frequency f, vibrations in the drive system can be suppressed. Furthermore, compared to the shaft torque Tax* in normal mode or eco mode, as shown by the dashed line in Figure 5, the torque output to the output shaft 42 can be reduced more rapidly. In sport mode, output responsiveness is important, and because the torque output to the output shaft 42 can be reduced more rapidly, torque responsiveness appropriate for sport mode can be achieved. This makes it possible to achieve both vibration suppression and torque responsiveness appropriate for the driving mode.

[0035] If the predetermined conditions are met in S130, the coefficient n is set to a value of 2 (S140). Then, the target drop time td is set to the reciprocal of the resonant frequency f of the drive system multiplied by the coefficient n (here, a value of 1) (S160). Furthermore, the elapsed time toff is input (S170). Then, using the above equation (1), the shaft torque Tax* is set so that the shaft torque Tax* output to the output shaft 42 gradually decreases toward the required torque Tout* over the target drop time td, within a range that does not fall below the required torque Tout* (S180). Once the shaft torque Tax* is set in this way, the engine 22 and motor 30 are controlled so that the shaft torque Tax* is output to the output shaft 42 (S190), and it is determined whether the shaft torque Tax* is equal to the required torque Tout* (S200). If the shaft torque Tax* is not equal to the required torque Tout*, the process returns to S170. If the shaft torque Tax* is equal to the required torque Tout*, this routine is terminated. When the predetermined conditions are met in S130, the coefficient n is set to a value of 2, so the torque output to the output shaft 42 can be reduced at the same rate as the shaft torque Tax* in normal mode or eco mode, as shown by the dashed line in Figure 5.

[0036] When the first of the predetermined conditions is met in S130, if the shaft torque Tax* set using the above equation (1) suddenly drops to a negative value, the power (negative value) actually used to charge the battery 60 may become smaller than the input limit Win (negative value), meaning the battery 60 may be charged with power exceeding the input limit Win. When the first condition is met, the coefficient n is increased to lengthen the target drop time td, thereby suppressing a sudden drop in the torque output from the motor 30. This prevents the battery 60 from being charged with power exceeding the input limit Win, thus protecting the battery 60.

[0037] When the second of the predetermined conditions is met, rapidly reducing the torque output from the engine 22 when the accelerator is released will supply more intake air to the purification catalyst 135a, causing the purification catalyst 135a to overheat. When ignition retardation is prohibited, increasing the coefficient n and lengthening the target reduction time td will suppress the rapid decrease in torque output from the motor 30. This will suppress the overheating of the purification catalyst 135a and protect it.

[0038] According to the hybrid vehicle 20 equipped with the vehicle control device of the embodiment described above, by setting the target reduction time td to be 1 or 2 times the reciprocal of the resonant frequency f of the drive system, depending on the driving mode, it is possible to achieve both vibration suppression and torque responsiveness according to the driving mode.

[0039] Furthermore, the multiple modes include a normal mode, an eco mode, and a sport mode that prioritizes torque output responsiveness for driving compared to the normal and eco modes. When the driving mode is sport mode, the coefficient n is made smaller compared to the normal and eco modes, thus improving torque responsiveness in sport mode.

[0040] Furthermore, when the driving mode is in sport mode, if a predetermined condition is met that prohibits rapidly reducing the torque output to the output shaft 42 as a drive shaft, the time for reducing the torque output to the output shaft 42 is increased compared to when the predetermined condition is not met, thus making it possible to extend the time for reducing the torque output to the output shaft 42.

[0041] Furthermore, since the predetermined conditions include a first condition that limits the torque output from the motor 30 in order to prevent the discharge power of the battery 60 from exceeding the output limit Wout, the torque responsiveness can be improved.

[0042] Furthermore, since the predetermined conditions include a second condition in which ignition retardation of the engine 22 is prohibited in order to suppress the temperature rise of the purification catalyst 135a, the temperature rise of the purification catalyst 135a can be suppressed and the purification catalyst 135a can be protected.

[0043] In the above embodiment, the coefficient n is set to a value of 1 when the driving mode is sport mode and the predetermined conditions are not met, and the coefficient n is set to a value of 2 when the driving mode is normal mode or eco mode, or when the driving mode is sport mode but the predetermined conditions are met. However, the coefficient n is an integer greater than or equal to 1, and when the driving mode is sport mode and the predetermined conditions are not met, the coefficient n should be set to a smaller value than when the driving mode is normal mode or eco mode, or when the driving mode is sport mode but the predetermined conditions are met. For example, the coefficient n may be set to a value of 2 when the driving mode is sport mode and the predetermined conditions are not met, and the coefficient n may be set to a value of 4 when the driving mode is normal mode or eco mode, or when the driving mode is sport mode and the predetermined conditions are met.

[0044] In the above embodiment, when the driving mode is sport mode, the coefficient n is set to a value of 1 when the predetermined conditions are not met, and the coefficient n is set to a value of 2 when the predetermined conditions are met. However, when the driving mode is sport mode, the coefficient n may be uniformly set to a value of 1 regardless of whether the predetermined conditions are met or not.

[0045] In the embodiment described above, the predetermined conditions include both the first and second conditions, but they may include only one of the first or second conditions. Furthermore, the predetermined conditions may include conditions different from the first and second conditions, as long as they prohibit rapidly reducing the torque output to the output shaft 42 as a drive shaft.

[0046] In the embodiments described above, the vehicle control device of this disclosure is applied to a hybrid vehicle 20 having an engine 22 and a motor 30. However, it may also be applied to a hybrid vehicle having an engine 22, a first motor, a planetary gear to which a carrier is connected to the output shaft of the engine 22 and the first motor is connected to a sun gear, and a second motor connected to the ring gear of the planetary gear. It may also be applied to an automobile having an engine 22 but no motor to output power for driving, or to an automobile having a motor but no engine.

[0047] Furthermore, the correspondence between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem is merely an example to specifically explain the form in which the embodiment implements the invention described in the section on means for solving the problem, and does not limit the elements of the invention described in the section on means for solving the problem. In other words, the interpretation of the invention described in the section on means for solving the problem should be based on the description in that section, and the embodiment is merely one specific example of the invention described in the section on means for solving the problem.

[0048] While embodiments for implementing this disclosure have been described above, this disclosure is not limited in any way to these embodiments, and can of course be implemented in various forms without departing from the gist of this disclosure. [Industrial applicability]

[0049] This disclosure can be used in industries such as the manufacturing of vehicle control devices. [Explanation of Symbols]

[0050] 20 Hybrid vehicles, 22 Engines, 30 Motors, 44 Input shafts, 45 Automatic transmissions, 60 Batteries, 70 HVECUs.

Claims

1. A vehicle control device used in a vehicle equipped with at least one power source that outputs power to a drive shaft connected to an axle, which controls the power source so that the vehicle runs in one driving mode selected from a plurality of modes, and controls the power source so that when the accelerator is released the torque output to the drive shaft gradually decreases over a target reduction time toward the required torque at the time the accelerator is released, The target deceleration time is set to be n times the reciprocal of the resonant frequency of the drive system including the power source. The aforementioned n is an integer with a value of 1 or greater, and is changed according to the driving mode. The aforementioned plurality of modes include a first mode and a second mode that places more emphasis on the output response of torque for driving compared to the first mode. When the driving mode is the second mode, the value of n is reduced compared to when it is the first mode. When the driving mode is the second mode, if a predetermined condition is met that prohibits rapidly reducing the torque output to the drive shaft, then the value of n is increased compared to when the predetermined condition is not met. Vehicle control device.

2. A vehicle control device according to claim 1, The vehicle comprises a motor as a power source and a battery that exchanges power with the motor, The predetermined conditions include a condition in which the absolute value of the input limit, which is the maximum allowable power that can be input to the battery, is smaller than a predetermined threshold. Vehicle control device.

3. A vehicle control device according to claim 1, The aforementioned vehicle is equipped with an engine as a power source, which has a purification device having a purification catalyst for purifying exhaust gases attached to the exhaust system. The aforementioned predetermined conditions include conditions in which ignition retardation, which delays the ignition timing of the engine to suppress the temperature rise of the purification catalyst, is prohibited. Vehicle control device.

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