Vehicle control device

Abstract

This invention suppresses unexpected forward lurching sensations for the driver. When driving in Mode 1 and using motor-driven operation, the engine and motor are controlled to drive at the required torque within a first upper limit torque range. When driving in Mode 1 and using hybrid operation, and in Mode 2 (different from Mode 1), the engine and motor are controlled to drive at the required torque within a second upper limit torque range greater than the first upper limit torque. When switching from motor-driven to hybrid operation or from Mode 1 to Mode 2 during driving in Mode 1, the engine and motor are controlled to drive at the required torque within the first upper limit torque range while the accelerator pedal opening remains constant.

Description

Technical Field

[0001] This invention relates to a vehicle control device. Background Technology

[0002] Conventionally, as such vehicle control devices, a vehicle control device for vehicles equipped with a motor and an engine has been proposed, which controls the motor and engine (for example, refer to Patent Document 1). In this device, the engine and motor are controlled to enable the vehicle to operate in multiple modes, including a first mode in which the motor operates without using engine power, taking precedence over hybrid driving using engine power. In this vehicle control device, in the first mode, the motor and engine are controlled to operate at a driving-required torque within a first upper limit torque range. Furthermore, in a second mode different from the first mode, the motor and engine are controlled to operate at a driving-required torque within a second upper limit torque range greater than the first upper limit torque.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2018-70760 Summary of the Invention

[0004] In the aforementioned vehicle control device, when driving in the first mode, if the driving torque is limited by the first upper limit torque, and the system switches from the first mode to the second mode, the actual driving torque increases because the second upper limit torque is greater than the first upper limit torque, which will give the driver an unexpected sense of forward momentum.

[0005] The main purpose of the vehicle control device of the present invention is to suppress the unexpected forward lurch that may cause the driver to lurch forward.

[0006] To achieve the aforementioned main objectives, the vehicle control device of the present invention employs the following means. The main purpose of the vehicle control device of the present invention is that it is used in a vehicle and controls an engine and an inverter to enable the vehicle to operate in multiple modes. The vehicle includes: an engine; a motor; an inverter that drives the motor; a battery connected to the inverter via a power line; and a charger connected to the power line and charging the battery using external power. The multiple driving modes include a first mode in which the motor operates without the engine's power, taking precedence over hybrid driving (using the engine's power) in favor of motor driving. In the vehicle control device, when operating in the first mode and using the motor, the engine and the motor are controlled to achieve a first upper limit torque. Within the range of driving, the engine and the motor are controlled to drive at the driving torque required during driving. When driving in the first mode and in the hybrid driving mode, and when driving in the second mode which is different from the first mode, the engine and the motor are controlled to drive at the driving torque within the range of the second upper limit torque which is greater than the first upper limit torque. In the first mode of driving, when switching from motor driving to hybrid driving, or when switching from the first mode of driving to the second mode of driving, when the opening of the accelerator pedal is constant, the engine and the motor are controlled to drive at the driving torque within the range of the first upper limit torque.

[0007] In the vehicle control device of this invention, when driving in a first mode using motor-driven operation, the engine and motor are controlled to drive at the required driving torque within a first upper limit torque range. When driving in a first mode using hybrid operation, and in a second mode different from the first mode, the engine and motor are controlled to drive at the required driving torque within a second upper limit torque range greater than the first upper limit torque. When switching from motor-driven to hybrid operation or from the first mode to the second mode during driving in the first mode, the engine and motor are controlled to drive at the required driving torque within the first upper limit torque range when the accelerator pedal opening is constant. When the accelerator pedal opening is constant, it is assumed that the driver desires a constant speed. Therefore, by controlling the engine and motor to drive at the required driving torque within the first upper limit torque range when the accelerator pedal opening is constant, unexpected forward lurching sensations to the driver can be suppressed.

[0008] In this vehicle control device of the present invention, during the first driving mode, when switching from motor-driven to hybrid driving, or when switching from the first driving mode to the second driving mode, when the accelerator pedal is depressed from a constant opening, the engine and the motor can be controlled such that the driving torque for driving increases within a predetermined time interval within the range of the second upper limit torque. When the accelerator pedal is depressed, it is assumed that the driver intends to accelerate. Therefore, during the first driving mode, when switching from motor-driven to hybrid driving, or when switching from the first driving mode to the second driving mode, when the accelerator pedal is depressed from a constant opening, controlling the engine and the motor such that the driving torque for driving increases within a predetermined time interval within the range of the second upper limit torque, thereby suppressing vehicle behavior contrary to the driver's intention.

[0009] Furthermore, in the vehicle control device of the present invention, during the first mode of driving, when switching from motor-driven operation to hybrid driving, or when switching from the first mode of driving to the second mode of driving, the engine and the motor can be controlled to reduce the driving torque within the range of the first upper limit torque by a predetermined time interval before the accelerator pedal is released from its constant opening state. This reduces the driving torque within the range of the first upper limit torque. When the accelerator pedal is released, it is assumed that the driver intends to decelerate. Therefore, during the first mode of driving, when switching from motor-driven operation to hybrid driving, or when switching from the first mode of driving to the second mode of driving, the engine and the motor are controlled to reduce the driving torque within the range of the first upper limit torque by a predetermined time interval before the accelerator pedal is released from its constant opening state, thereby suppressing any unexpected forward lurch to the driver. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of a hybrid electric vehicle equipped with a vehicle control device according to an embodiment of the present invention.

[0011] Figure 2 This is a flowchart representing an example of a transfer control routine executed by the HVECU.

[0012] Figure 3 This is an explanatory diagram illustrating an example of the time-varying changes in throttle opening (Acc), driving request torque (Td*), maximum torque (Tmax), and driving mode. Detailed Implementation

[0013] Embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a schematic configuration diagram of a hybrid electric vehicle 20 equipped with a vehicle control device according to an embodiment of the present invention. As shown, the hybrid electric vehicle 20 of the embodiment includes: an engine 22; a planetary gear 30; motors MG1 and MG2; inverters 41 and 42; a battery 50; a charger 60; and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70.

[0014] The engine 22 is configured as an internal combustion engine that outputs power using gasoline, light oil, or the like as fuel. The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as the engine ECU) 24.

[0015] Although not illustrated, the engine ECU 24 is configured as a CPU-centric microprocessor. In addition to the CPU, it includes a ROM for storing processing programs, RAM for temporary data storage, input / output ports, and a communication port. Signals from various sensors required to control the operation of the engine 22 are input to the engine ECU 24 via the input ports. Examples of signals input to the engine ECU 24 include the crankshaft angle θcr from the crankshaft position sensor 23 (which detects the rotational position of the crankshaft 26 of the engine 22) or the throttle opening TH from the throttle valve position sensor (which detects the position of the throttle valve). Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 via the output ports. The engine ECU 24 is connected to the HVECU 70 via a communication port, controlling the engine 22 based on control signals from the HVECU 70, and outputting data related to the operating state of the engine 22 to the HVECU 70 as needed. The engine ECU 24 calculates the rotational speed of the crankshaft 26, i.e., the rotational speed Ne of the engine 22, based on the crankshaft angle θcr from the crankshaft position sensor 23.

[0016] Planetary gear 30 is configured as a single-pinion planetary gear mechanism. The rotor of motor MG1 is connected to the sun gear of planetary gear 30. A drive shaft 36, which is connected to drive wheels 38a and 38b via differential gear 37, is connected to the internal gear ring of planetary gear 30. The crankshaft 26 of engine 22 is connected to the planet carrier of planetary gear 30 via damper 28.

[0017] Motor MG1 is configured, for example, as a synchronous generator motor, with its rotor connected to the sun gear of planetary gear 30 as described above. Motor MG2 is configured, for example, as a synchronous generator motor, with its rotor connected to drive shaft 36. Inverters 41 and 42 are connected to battery 50 via power line 54. Motors MG1 and MG2 are driven to rotate by switching control of multiple switching elements (not shown) of inverters 41 and 42 via motor electronic control unit (hereinafter referred to as "motor ECU") 40.

[0018] Although not shown, the motor ECU 40 is configured as a CPU-centric microprocessor. In addition to the CPU, it also includes a ROM for storing processing programs, RAM for temporary data storage, input / output ports, and a communication port. Signals from various sensors required for driving and controlling motors MG1 and MG2 are input to the motor ECU 40 via the input ports. Examples of signals input to the motor ECU 40 include rotational position sensors 43 and 44 (θm1 and θm2) that detect the rotational position of the rotors of motors MG1 and MG2, or phase current sensors that detect the current flowing through each phase of motors MG1 and MG2. The motor ECU 40 outputs switching control signals to multiple switching elements (not shown) of inverters 41 and 42 via the output ports. The motor ECU 40 is connected to the HVECU 70 via the communication port, driving and controlling motors MG1 and MG2 using control signals from the HVECU 70, and outputting data related to the driving state of motors MG1 and MG2 to the HVECU 70 as needed. The motor ECU 40 calculates the rotational speeds Nm1 and Nm2 of motors MG1 and MG2 based on the rotational positions θm1 and θm2 of the rotors of motors MG1 and MG2 obtained from the rotational position detection sensors 43 and 44.

[0019] The battery 50 is configured as, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery. As described above, the battery 50 is connected to the inverters 41 and 42 via power lines 54. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as "battery ECU") 52.

[0020] Although not shown, the battery ECU 52 is configured as a CPU-centric microprocessor. In addition to the CPU, it also includes a ROM for storing processing programs, RAM for temporary data storage, input / output ports, and a communication port. Signals from various sensors required for managing the battery 50 are input to the battery ECU 52 through the input ports. Examples of signals input to the battery ECU 52 include the battery voltage Vb from the voltage sensor 51a located between the terminals of the battery 50, the battery current Ib from the current sensor 51b mounted on the output terminals of the battery 50, and the battery temperature Tb from the temperature sensor 51c mounted on the battery 50. The battery ECU 52 is connected to the HVECU 70 via the communication port and outputs data related to the state of the battery 50 to the HVECU 70 as needed. The battery ECU 52 calculates the state of charge (SOC) based on the accumulated value of the battery current Ib from the current sensor 51b. The SOC is the ratio of the capacity of electricity that can be discharged from the battery 50 to the total capacity of the battery 50.

[0021] The charger 60 is connected to the power line 54, configured to charge the battery 50 using power from the external power source 69 when the power plug 61 is connected to an external power source 69 such as a household power supply. The charger 60 includes an AC / DC converter and a DC / DC converter. The AC / DC converter converts the alternating current (AC) power supplied from the external power source 69 via the power plug 61 into direct current (DC). The DC / DC converter converts the voltage of the DC power from the AC / DC converter and supplies it to the battery 50. In this charger 60, when the power plug 61 is connected to the external power source 69, the AC / DC converter and DC / DC converter are controlled by the HVECU 70, thereby supplying power from the external power source 69 to the battery 50.

[0022] Although not shown, the HVECU70 is configured as a CPU-centric microprocessor. In addition to the CPU, it also includes a ROM for storing processing programs, RAM for temporary data storage, flash memory 72, input / output ports, and a communication port. Signals from various sensors are input to the HVECU70 via the input ports. Examples of signals input to the HVECU70 include the ignition signal from the ignition switch 80, the shift position SP from the shift position sensor 82 (detecting the operating position of the shift lever 81), the throttle opening Acc from the throttle pedal position sensor 84 (detecting the amount of pressure applied to the accelerator pedal 83), and the brake pedal position BP from the brake pedal position sensor 86 (detecting the amount of pressure applied to the brake pedal 85). Also included is the vehicle speed V from the vehicle speed sensor 88. Furthermore, examples include the connection signal SWC from the connection switch 62 installed on the power plug 61 and used to determine whether the power plug 61 is connected to an external power source 69. The HVECU70 outputs control signals to the charger 60 via the output ports. As described above, HVECU70 is connected to engine ECU24, motor ECU40, and battery ECU52 via a communication port, and exchanges various control signals or data with engine ECU24, motor ECU40, and battery ECU52.

[0023] In the hybrid vehicle 20 configured in this way, in EV priority mode (mode 1) or hybrid mode (mode 2), it can drive in hybrid mode (HV driving) with the engine 22 running, or drive in motor mode (EV driving) with the power from the motor MG2 without the engine 22 running.

[0024] In this implementation, when the vehicle is parked with the system shut down (system stopped) at a charging point such as a residence or charging station, if the power plug 61 is connected to an external power source 69, the HVECU 70 controls the charger 60 to charge the battery 50 using power from the external power source 69. Furthermore, if the system is turned on (system started), the temporary driving mode becomes hybrid mode. However, when the battery 50's state of charge (SOC) is greater than a threshold Shv1 (e.g., 45%, 50%, 55%) when the system is turned on (system started), the vehicle drives in EV priority mode until the battery 50's SOC reaches or falls below a threshold Shv2 (e.g., 25%, 30%, 35%). After the battery 50's SOC reaches or falls below the threshold Shv2, the vehicle drives in hybrid mode until the system is turned off. Additionally, when the battery 50's SOC is below the threshold Shv1 when the system is turned on, the vehicle drives in hybrid mode until the system is turned off.

[0025] When the motor is running in EV priority mode or hybrid mode, HVECU70 first sets the required driving torque Td* based on the throttle opening Acc and vehicle speed V. Next, the smaller of the upper limit torque Tmax and the driving torque Td* is set as the required torque Tr* to drive shaft 36. The upper limit torque Tmax is set as the first upper limit torque Tmax1 in EV priority mode and as the second upper limit torque Tmax2, which is larger than the first upper limit torque Tmax1, in hybrid mode. Then, the value 0 is set as the torque command Tm1* for motor MG1, and the torque command Tm2* for motor MG2 is set so that the required torque Tr* is output to drive shaft 36. Finally, the torque commands Tm1* and Tm2* for motors MG1 and MG2 are sent to motor ECU40. If the motor ECU40 receives torque commands Tm1* and Tm2* from motors MG1 and MG2, it will control the switching elements of inverters 41 and 42 to drive motors MG1 and MG2 according to the torque commands Tm1* and Tm2*.

[0026] When driving in EV priority mode or hybrid mode, the HVECU70 first sets the required driving torque Td* based on the throttle opening Acc and vehicle speed V. Next, the smaller of the upper limit torque Tmax and the driving torque Td* is set as the required torque Tr* to the drive shaft 36. The set torque Tr* is multiplied by the rotational speed Nr of the drive shaft 36 to calculate the required driving power Pr*. The upper limit torque Tmax is set as the second upper limit torque Tmax2 in hybrid driving. Here, the rotational speed Nr of the drive shaft 36 can be the rotational speed Nm2 of the motor MG2, or the speed obtained by multiplying the vehicle speed V by a conversion factor, etc. Then, the required power Pe* of the vehicle is calculated by subtracting the charging / discharging power Pb* of the battery 50 (which is positive when discharging from the battery 50) from the driving power Pr*. Here, in hybrid mode, the charge / discharge request power Pb* is set to 0 when the state of charge (SOC) of the battery 50 is at the target ratio SOC* (a specified value or the SOC when switching from EV priority mode, etc.), a negative value (for charging) is set when the SOC is less than the target ratio SOC*, and a positive value (for discharging) is set when the SOC is greater than the target ratio SOC*. Furthermore, in EV priority mode, the charge / discharge request power Pb* is set to 0 regardless of the SOC. Next, the target speed Ne* and target torque Te* of the engine 22 are set using the requested power Pe* and the operating line for effectively operating the engine 22. The target speed Ne* and target torque Te* are generally larger when the requested power Pe* is large than when it is small. Next, the torque command Tm1* of the motor MG1 is set by speed feedback control to make the speed Ne of the engine 22 the target speed Ne*, and the torque command Tm2* of the motor MG2 is set so that the requested torque Tr* is output to the drive shaft 36. Then, the target speed Ne* and target torque Te* of engine 22 are sent to engine ECU 24, and the torque commands Tm1* and Tm2* of motors MG1 and MG2 are sent to motor ECU 40. If engine ECU 24 receives the target speed Ne* and target torque Te* of engine 22, it performs intake air volume control, fuel injection control, ignition control, etc., of engine 22 to operate engine 22 based on the received target speed Ne* and target torque Te*. If motor ECU 40 receives the torque commands Tm1* and Tm2* of motors MG1 and MG2, it performs switching control of multiple switching elements of inverters 41 and 42 to drive motors MG1 and MG2 according to the torque commands Tm1* and Tm2*.

[0027] When the motor drives in EV priority mode, the HVECU 70 starts the engine 22 and switches to hybrid driving in EV priority mode when a request for the engine 22 to operate to ensure the performance (heating performance) of the air conditioning system that uses the engine 22 as a heat source is made. When hybrid driving in EV priority mode, the HVECU 70 stops the engine 22 and switches to motor driving when a request for the engine 22 to operate to ensure the performance (heating performance) of the air conditioning system that uses the engine 22 as a heat source is not made.

[0028] Next, the operation of the hybrid vehicle 20 equipped with the vehicle control device configured in this way will be explained, especially the operation when setting the requested torque Tr* when switching from motor driving in EV priority mode to hybrid driving. Figure 2 This is a flowchart illustrating an example of a transfer control routine executed by the HVECU70. This routine is executed by the CPU of the HVECU70 when switching from motor-driven operation in EV-priority mode to hybrid operation.

[0029] If this routine is executed, the HVECU70 determines whether the throttle opening Acc from the throttle pedal position sensor 84 is constant (S100). When the throttle opening Acc is constant, the HVECU70 sets the upper limit torque Tmax to the first upper limit torque Tmax1 (S110). Moreover, the HVECU70 sets the smaller of the driving request torque Td* based on the throttle opening Acc and the vehicle speed V and the upper limit torque Tmax as the request torque Tr* (S120). When the request torque Tr* is set in this way, the HVECU70 uses the request torque Tr* to control the engine 22 and motors MG1 and MG2 with the same processing as the hybrid driving in the EV priority mode described above (S190), and ends this routine. Thus, when the throttle opening Acc is constant, the HVECU70 can control the engine 22 and motors MG1 and MG2 to drive within the upper limit torque Tmax (=Tmax1) at the driving request torque Td*.

[0030] When the throttle opening Acc is not constant in S100, HVECU70 determines whether the throttle opening Acc has increased (S130). When the throttle opening Acc increases, HVECU70 sets the upper limit torque Tmax to the second upper limit torque Tmax2 (S140). Then, HVECU70 sets the smaller of the torque obtained by adding the time change ΔTr of the previously set requested torque Tr* (previous Tr*) and the upper limit torque Tmax to the requested torque Tr* (S150). The time change ΔTr is a preset value used to make the requested torque Tr* change rapidly to a degree that does not cause a shock to the vehicle. When the requested torque Tr* is set in this way, HVECU70 uses the requested torque Tr* to control the engine 22 and motors MG1 and MG2 with the same processing as the hybrid driving in the EV priority mode described above (S190), and ends this routine. Thus, when the throttle opening Acc increases, that is, when the throttle pedal 83 is pressed, the HVECU70 controls the engine 22 and motors MG1 and MG2 to request an increase in torque Td* within the range of the upper limit torque Tmax (=Tmax2).

[0031] When the throttle opening Acc does not increase in S130, i.e., when the throttle opening Acc decreases, the HVECU70 determines whether the driving request torque Td* is below the first upper limit torque Tmax1 (S160). When the driving request torque Td* exceeds the first upper limit torque Tmax1, the HVECU70 sets the upper limit torque Tmax to the first upper limit torque Tmax1 (S110). Moreover, the HVECU70 sets the smaller of the driving request torque Td* and the upper limit torque Tmax based on the throttle opening Acc and the vehicle speed V as the request torque Tr* (S120). At this time, since the driving request torque Td* exceeds the first upper limit torque Tmax1, the upper limit torque Tmax (= Tmax1) is set as the request torque Tr*. When the request torque Tr* is set in this way, the HVECU70 uses the request torque Tr* to control the engine 22 and motors MG1 and MG2 with the same processing as the hybrid driving in the EV priority mode described above (S190), and ends this routine. Thus, when the throttle opening Acc decreases and the driving request torque Td* exceeds the first upper limit torque Tmax1, the HVECU70 controls the engine 22 and motors MG1 and MG2 to drive within the upper limit torque Tmax (= Tmax1) at the driving request torque Td* (here, driving at the upper limit torque Tmax).

[0032] When the driving request torque Td* in S160 is below the first upper limit torque Tmax1, the upper limit torque Tmax is set to the second upper limit torque Tmax2 (S170). Then, HVECU70 sets the smaller of the previously set request torque Tr* (previous Tr*) and the upper limit torque Tmax as the request torque Tr* (S180). When the request torque Tr* is set in this way, HVECU70 uses the request torque Tr* to control the engine 22 and motors MG1 and MG2 with the same processing as the hybrid driving in EV priority mode described above (S190), and ends this routine. Thus, when the throttle opening Acc decreases, that is, when the accelerator pedal 83 is released, HVECU70 controls the engine 22 and motors MG1 and MG2 to reduce the driving request torque Td* within the upper limit torque Tmax (=Tmax2).

[0033] Figure 3 This is an explanatory diagram illustrating an example of the time-varying changes in throttle opening Acc, driving request torque Td*, upper limit torque Tmax, and driving mode. At time t0, when the hybrid vehicle 20 system is activated (system starts), the driving mode is temporarily set to hybrid mode. When the state of charge (SOC) of the battery 50 is greater than the threshold Shv1 at system activation (system starts) (time t1), the driving mode becomes motor-driven in EV priority mode. At this time, the upper limit torque Tmax is set to the first upper limit torque Tmax1. At time t2, if a request is made to operate the engine 22 to ensure the performance (heating performance) of the air conditioning unit, the driving mode becomes hybrid driving in EV priority mode. At this time, with the throttle opening Acc constant, the upper limit torque Tmax remains at the first upper limit torque Tmax1 (S100, S110). With the throttle opening Acc constant, it is assumed that the driver desires to drive at a constant speed. Therefore, when the throttle opening Acc is constant, by controlling the engine 22 and the motors MG1 and MG2, the vehicle can be driven within the range of the upper limit torque Tmax (=Tmax1) at the driving request torque Td*, thereby suppressing the unexpected forward lurch that may cause the driver.

[0034] When the accelerator pedal 83 is depressed at time t3 (when the throttle opening Acc increases), the upper limit torque Tmax is set to the second upper limit torque Tmax2. The torque obtained by adding the time change ΔTr of the previously set requested torque Tr* (previous Tr*) and the smaller torque between the upper limit torque Tmax is set as the requested torque Tr*. Using the requested torque Tr*, the engine 22 and motors MG1 and MG2 are controlled in the same way as in the hybrid driving in EV priority mode (S130~S150). When the accelerator pedal is depressed, it is assumed that the driver intends to accelerate. Therefore, in the case of switching from motor driving to hybrid driving in EV priority mode, when the accelerator pedal 83 is depressed from a constant throttle opening Acc, the engine 22 and motors MG1 and MG2 are controlled so that the driving torque (the torque output to the drive shaft 36) increases with a time change ΔTr within the range of the upper limit torque Tmax (=Tmax2), thereby suppressing vehicle behavior contrary to the driver's intention.

[0035] If, at time t4, the throttle opening Acc remains constant and the engine 22, used to ensure the performance of the air conditioning system (heating performance), requests to stop operation, the driving mode becomes motor-driven in EV priority mode, and the upper limit torque Tmax is set to the first upper limit torque Tmax1. If, at time t5, the engine 22, used to ensure the performance of the air conditioning system (heating performance), requests to operate again, the driving mode becomes hybrid driving in EV priority mode again. At this time, if the accelerator pedal 83 is released (throttle opening Acc decreases), the driving request torque Td* decreases, but the upper limit torque Tmax is set to the first upper limit torque Tmax1, until the driving request torque Td* falls below the first upper limit torque Tmax1 (S160, S110). When the accelerator pedal 83 is released, it is assumed that the driver intends to decelerate. Therefore, when switching from motor-driven driving to hybrid driving in EV priority mode, when the accelerator pedal 83 is released from a constant throttle opening (Acc), before the driving request torque Td* becomes below the first upper limit torque Tmax1, the engine 22 and motors MG1 and MG2 are controlled so that the driving torque (torque output to drive shaft 36) decreases by a time change ΔTr within the range of the upper limit torque Tmax (=Tmax1), thereby suppressing the unexpected forward lurch that may cause the driver to experience.

[0036] According to the hybrid electric vehicle 20 equipped with the vehicle control device of this embodiment described above, when switching from motor driving to hybrid driving in EV priority mode, and when the throttle opening Acc is constant, the engine 22 and motors MG1 and MG2 are controlled to drive within the range of the upper limit torque Tmax (=Tmax1) with the driving request torque Td*, thereby suppressing the unexpected forward lurch to the driver.

[0037] Furthermore, in EV priority mode, when the engine 22 is started from motor driving and the hybrid driving mode is switched, when the accelerator pedal 83 is pressed from a constant throttle opening Acc, the engine 22 and motors MG1 and MG2 are controlled so that the driving torque (the torque output to the drive shaft 36) increases with a time change ΔTr within the range of the upper limit torque Tmax (=Tmax2), thereby suppressing vehicle behavior contrary to the driver's intention.

[0038] Furthermore, when switching from motor-driven driving to hybrid driving in EV priority mode, when the accelerator pedal 83 is released from a constant throttle opening (Acc), before the driving request torque Td* falls below the first upper limit torque Tmax1, the engine 22 and motors MG1 and MG2 are controlled so that the driving torque (torque output to the drive shaft 36) decreases by a time variation ΔTr within the range of the upper limit torque Tmax (=Tmax1), thereby suppressing any unexpected forward lurch to the driver.

[0039] In the above implementation, when switching from motor driving in EV priority mode to hybrid driving, the following is executed: Figure 2 The transition control routine. However, it can also be executed instead of the transition from motor drive to hybrid drive in EV priority mode, or simultaneously with the transition from motor drive to hybrid drive in EV priority mode, when transitioning from EV priority mode to hybrid mode. Figure 2 The transfer control routine.

[0040] In the above embodiments, S120 and S190 can be executed after setting the upper limit torque Tmax to the second upper limit torque Tmax2 without executing S160 to S180 and when the throttle opening Acc does not increase in S130. Furthermore, S160 can be executed without executing S130 to S150 and when the throttle opening Acc is not constant in S100. Additionally, S120 and S190 can be executed after setting the upper limit torque Tmax to the second upper limit torque Tmax2 without executing S130 to S180 and when the throttle opening Acc is not constant in S100.

[0041] In the above embodiments, the vehicle control device of the present invention is used in a hybrid electric vehicle 20 comprising an engine 22, motors MG1 and MG2, planetary gears 30, inverters 41 and 42, a battery 50, and a charger 60. However, the vehicle control device of the present invention can be used in any vehicle as long as it comprises an engine, a motor, an inverter that drives the motor, a battery connected to the inverter via a power line, and a charger connected to the power line and using external power to charge the battery.

[0042] Furthermore, the correspondence between the principal elements of the implementation method and the principal elements of the invention described in the "Means for Solving the Problem" column is merely an example of how the implementation method is used to carry out the invention described in the "Means for Solving the Problem" column, and therefore does not limit the elements of the invention described in the "Means for Solving the Problem" column. That is, the interpretation of the invention described in the "Means for Solving the Problem" column should be based on the description in that column, and the implementation method is simply a specific example of the invention described in the "Means for Solving the Problem" column.

[0043] The present invention has been described above using embodiments, but the present invention is not limited to such embodiments and can of course be implemented in various ways without departing from the spirit of the present invention.

[0044] Industrial availability

[0045] This invention can be used in industries such as the manufacturing of vehicle control devices.

[0046] Symbol Explanation

[0047] 20 - Hybrid vehicle, 22 - Engine, 24 - Engine ECU, 40 - Motor ECU, 41, 42 - Inverter, 50 - Battery, 60 - Charger, 70 - HVECU, MG1, MG2 - Motor.

Claims

1. A vehicle control device for a vehicle, controlling an engine and an inverter to enable the vehicle to operate in multiple modes, the vehicle comprising: an engine; a motor; an inverter driving the motor; a battery connected to the inverter via a power line; and a charger connected to the power line and charging the battery using external power, the multiple modes of operation including a first mode of motor-driven operation that prioritizes hybrid operation using the power of the engine over hybrid operation, the vehicle control device being characterized in that... When driving in the first mode and using the motor, the engine and the motor are controlled to drive at the required driving torque within a first upper limit torque range. When driving in the first mode and using the hybrid driving mode, and when driving in a second mode different from the first mode, the engine and the motor are controlled to drive at the required driving torque within a second upper limit torque range greater than the first upper limit torque. In the first mode of driving, when switching from motor driving to hybrid driving, or when switching from the first mode of driving to the second mode of driving, when the accelerator pedal opening is constant, the engine and the motor are controlled to drive at the driving request torque within the range of the first upper limit torque.

2. The vehicle control device according to claim 1, characterized in that, In the first mode of driving, when switching from the motor-driven engine to the hybrid driving mode, or when switching from the first mode of driving to the second mode of driving, when the accelerator pedal is depressed from a constant opening, the engine and the motor are controlled such that the driving torque for driving increases within the range of the second upper limit torque by a predetermined amount of time.

3. The vehicle control device according to claim 1, characterized in that, In the first mode of driving, when switching from motor-driven driving to hybrid driving, or when switching from the first mode of driving to the second mode of driving, the accelerator pedal is released from a constant opening state and the engine and the motor are controlled such that the driving torque for driving decreases within the range of the first upper limit torque by a predetermined amount of time before the driving request torque becomes below the first upper limit torque.

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