Vehicle control device

Abstract

To suppress deterioration of NV in a vehicle.SOLUTION: During execution of NV suppression control for suppressing noise or vibration in a vehicle by changing an operating point of a power source, execution of turning-behavior control to control a vehicular behavior by changing torque of the power source at the vehicle turning is inhibited, thus avoiding an event that the operating point of the power source from entering a given zone in which NV tends to occur as a result of a change in torque of the power source in association with turning-behavior control, that is, the change of the operating point of the power source or an event that the NV suppression control is not appropriately executed. Therefore, it is possible to suppress deterioration of the NV in a vehicle.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a control device for a vehicle equipped with a power source. [Background technology]

[0002] Control devices for vehicles equipped with a power source are well known. For example, a vehicle driving force control device is described in Patent Document 1. Patent Document 1 discloses that an engine is provided as a power source, that a target value for the yaw rate is set at the beginning of a turn when the steering angle starts to change, that a yaw moment is calculated as an operation amount for controlling the yaw rate to the target value, and that a correction amount for a torque command value for the engine corresponding to the yaw moment is calculated and that the engine is operated so as to achieve the torque command value corrected by the correction amount. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-133811 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the torque of the power source is corrected, for example, reduced, to control the vehicle behavior during cornering, the operating point of the power source is changed. As a result, the operating point of the power source may be placed within a predetermined region where NV is likely to occur, or the operation of the power source may not be properly controlled to suppress NV. This may worsen NV. "NV" is a general term for noise and vibration generated by a vehicle, and refers to at least one of noise and vibration in a vehicle.

[0005] The present invention has been made in light of the above circumstances, and an object of the present invention is to provide a vehicle control device that can suppress deterioration of NV in a vehicle. [Means for solving the problem]

[0006] The gist of a first invention is (a) a control device for a vehicle equipped with a power source, (b) The vehicle includes an engine that functions as the power source, an electric transmission mechanism that has a differential mechanism to which the engine is connected so as to be able to transmit power, and a first electric motor that is connected so as to be able to transmit power to the differential mechanism, and in which the differential state of the differential mechanism is controlled by controlling the operating state of the first electric motor, and a second electric motor that functions as the power source and is connected so as to be able to transmit power to drive wheels, and (c) an NV suppression control unit that performs NV suppression control to suppress noise or vibration in the vehicle by changing an operating point represented by the rotation speed and torque of the power source; d ) a turning behavior control unit that performs turning behavior control to control the behavior of the vehicle by changing the torque of the power source when the vehicle is turning; e a control prohibition determination unit that prohibits the execution of the turning behavior control while the NV suppression control is being executed. (f) the NV suppression control is a control for moving the operating point of the engine out of a predetermined region where the noise or the vibration is likely to occur, or a control for operating the second electric motor so as to cancel out the vibration. The reason is that. [Effects of the Invention]

[0007] According to the first aspect of the present invention, the execution of turning behavior control is prohibited during execution of NV suppression control, so that it is possible to prevent the operating point of the power source from entering a predetermined region where NV is likely to occur due to a change in the torque of the power source, i.e., a change in the operating point of the power source, accompanying the turning behavior control, and to prevent the NV suppression control from being performed inappropriately, thereby suppressing the deterioration of NV in the vehicle. In addition, the NV suppression control is a control that moves the engine operating point out of a predetermined region where NV is likely to occur, or a control that operates the second electric motor so as to cancel out vibrations, so that NV is appropriately suppressed. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a schematic configuration of a vehicle to which the present invention is applied, and is also a diagram illustrating main parts of control functions and control systems for various controls in the vehicle. [Figure 2] FIG. 10 is a diagram showing an example of a time chart when line tracing control is activated. [Figure 3] 1 is a flowchart illustrating a main part of the control operation of an electronic control device, and is a flowchart illustrating the control operation for suppressing deterioration of NV in a vehicle. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. [Example]

[0010] Fig. 1 is a diagram illustrating the schematic configuration of a vehicle 10 to which the present invention is applied, as well as a diagram illustrating the main parts of the control functions and control systems for various controls in the vehicle 10. In Fig. 1, the vehicle 10 is a hybrid vehicle equipped with an engine 12 as a power source and a second electric motor MG2, which is also an electric motor as a power source. The vehicle 10 also has drive wheels 14, a power transmission device 16 provided in a power transmission path between the engine 12 and the drive wheels 14, and a first electric motor MG1.

[0011] The engine 12 is a known internal combustion engine. An electronic control device 80 (described later) controls an engine control device 50, which includes a throttle actuator, a fuel injection device, an ignition device, and the like, provided in the vehicle 10, thereby controlling the engine torque Te of the engine 12.

[0012] The first electric motor MG1 and the second electric motor MG2 are known rotating electric machines, so-called motor generators, that function as both a motor that generates mechanical power from electric power and a generator that generates electric power from mechanical power. Each electric motor is connected to a battery 54 provided in the vehicle 10 via an inverter 52 provided in the vehicle 10. The inverter 52 is controlled by an electronic control device 80 (described later), thereby controlling the MG1 torque Tg of the first electric motor MG1 and the MG2 torque Tm of the second electric motor MG2. The torque of each electric motor is a positive torque, which is the acceleration side that generates power from the supplied electric power, when the electric motor rotates in the forward direction, which is the same direction as the engine 12 when it is operating. The torque of each electric motor is a negative torque, which is the deceleration side that generates electric power from the input power, when it rotates in the forward direction, which is a regenerative torque. The first electric motor MG1 and the second electric motor MG2 are mounted in a case 18, which is a non-rotating member attached to the vehicle body. The term "electric power" also refers to electrical energy unless otherwise specified. Unless otherwise specified, the power also includes driving force, torque, and force.

[0013] The power transmission device 16 includes, within a case 18, a damper 20, an input shaft 22, a transmission unit 24, a drive gear 26, a driven gear 28, a driven shaft 30, a final gear 32, a differential gear 34, a reduction gear 36, and the like. The input shaft 22 functions as an input rotating member of the transmission unit 24 and is connected to the crankshaft 12a of the engine 12 via the damper 20 and the like. The transmission unit 24 is connected to the input shaft 22. The drive gear 26 is an output rotating member of the transmission unit 24. The driven gear 28 meshes with the drive gear 26. The driven shaft 30 fixedly mounts the driven gear 28 and the final gear 32 so that they cannot rotate relative to each other. The final gear 32 has a smaller diameter than the driven gear 28 and meshes with a differential ring gear 34a of the differential gear 34. The reduction gear 36 has a smaller diameter than the driven gear 28 and is in mesh with the driven gear 28. A rotor shaft of the second electric motor MG2 is connected to the reduction gear 36, and the second electric motor MG2 is connected to the reduction gear 36 so as to be able to transmit power. The power transmission device 16 also includes a pair of drive shafts 38 connected to the differential gear 34.

[0014] The power transmission device 16 configured in this manner is suitable for use in FF (front engine, front drive) or RR (rear engine, rear drive) vehicles. The power transmission device 16 transmits the power output from the engine 12 and the second electric motor MG2 to the driven gear 28, and then from the driven gear 28 to the drive wheels 14 via the final gear 32, differential gear 34, drive shaft 38, etc. In this manner, the second electric motor MG2 is connected to the drive wheels 14 so as to be able to transmit power.

[0015] The transmission unit 24 constitutes part of the power transmission device 16 and transmits the power of the engine 12 to the driven gear 28. The transmission unit 24 includes a first electric motor MG1 and a differential mechanism 40. The differential mechanism 40 is configured as a known single-pinion planetary gear device and includes a sun gear S, a carrier CA, and a ring gear R. The carrier CA is a rotating element to which the engine 12 is connected via the input shaft 22 or the like so as to be able to transmit power. The sun gear S is a rotating element to which the first electric motor MG1 is connected so as to be able to transmit power. The ring gear R is integrally connected to the drive gear 26 and is a rotating element connected to the drive wheels 14 so as to be able to transmit power. The differential mechanism 40 is a power split mechanism that mechanically splits the power of the engine 12 input to the carrier CA between the first electric motor MG1 and the drive gear 26.

[0016] In the differential mechanism 40, when the MG1 torque Tg, which is a negative reaction torque against the engine torque Te, which is a positive torque, input to the carrier CA, is input to the sun gear S, a positive direct torque Td appears in the ring gear R. The direct torque Td is expressed as "Te / (1+ρ)", i.e., "-(1 / ρ)×Tg", where "ρ" is the gear ratio of the differential mechanism 40 (= number of teeth of the sun gear / number of teeth of the ring gear). Then, the combined torque of the direct torque Td and the MG2 torque Tm, which are respectively transmitted to the driven gear 28 in accordance with the required drive torque Trdem, is transmitted to the drive wheels 14 as the drive torque Tr of the vehicle 10. At this time, the transmission 24 can be operated as a continuously variable transmission in which the speed ratio γ (= input rotational speed Ni / output rotational speed No) can be changed continuously. That is, in the HEV driving mode, the transmission unit 24 can be operated as an electric transmission, for example, an electric continuously variable transmission, in which the differential state of the differential mechanism 40 is controlled by controlling the operating state of the first electric motor MG1. The HEV driving mode is a driving mode in which at least engine driving using the engine 12 as a power source, i.e., hybrid driving (=HEV driving), is possible. Therefore, in the HEV driving mode, it is possible to control the engine operating point to be set to an efficient operating point. The operating point is a driving point expressed by rotation speed and torque, and the engine operating point is a driving point of the engine 12 expressed by the engine rotation speed Ne and the engine torque Te. Note that controlling the operating state of the first electric motor MG1 is equivalent to controlling the operation of the first electric motor MG1. The engine rotation speed Ne is the rotation speed of the engine 12. The input rotation speed Ni is the rotation speed of the input shaft 22 and is equal to the engine rotation speed Ne. The output rotation speed No is the rotation speed of the drive gear 26.

[0017] On the other hand, in the power transmission device 16, in the BEV driving mode, the first electric motor MG1 is in an unloaded state and is allowed to idle at negative rotation, and the carrier CA is set to zero rotation, i.e., the engine rotation speed Ne is set to zero. In this state, the MG2 torque Tm, which is a positive torque transmitted to the driven gear 28, is transmitted to the drive wheels 14 as a drive torque Tr in the forward direction of the vehicle 10. The BEV driving mode is a driving mode in which the vehicle can run on its own motor (=BEV driving) using the second electric motor MG2 as a power source while the engine 12 is stopped.

[0018] The vehicle 10 further includes an electronic control device 80 as a controller including control devices for the vehicle 10 related to the control of the engine 12, the first electric motor MG1, the second electric motor MG2, etc. The electronic control device 80 includes a so-called microcomputer equipped with, for example, a CPU, RAM, ROM, an input / output interface, etc. The CPU executes various controls of the vehicle 10 by performing signal processing in accordance with programs stored in the ROM in advance while utilizing the temporary storage function of the RAM. The electronic control device 80 includes computers for engine control, electric motor control, etc. as necessary.

[0019] The electronic control device 80 receives various signals (for example, an engine rotation speed Ne that is the same as the input rotation speed Ni, an output rotation speed No corresponding to the vehicle speed V, an MG1 rotation speed Ng that is the rotation speed of the first electric motor MG1, a rotation speed Ng of the second electric motor MG2, a rotation speed Ng of the first electric motor MG1, a rotation speed Ng of the second electric motor MG2, a rotation speed Ng of the second electric motor MG3, a rotation speed Ng of the first electric motor MG4, a rotation speed Ng of the second electric motor MG5, a rotation speed Ng of the second electric motor MG6, a rotation speed Ng of the first electric motor MG7, a rotation speed Ng of the second electric motor MG8, a rotation speed Ng of the second electric motor MG9, a rotation speed Ng ...1, a rotation speed Ng of the second electric motor MG2, a rotation speed Ng of the first electric motor MG1, a rotation speed Ng of the second electric motor MG2, a rotation speed Ng of the first electric motor MG1, a rotation speed Ng of the second electric motor MG2, a rotation speed Ng of the first electric motor MG1, a rotation speed Ng of the second electric motor MG2, a rotation speed Ng of the first electric motor MG1, a rotation speed Ng of the second electric motor MG2 The vehicle 10 is supplied with the following parameters: MG2 rotation speed Nm, which is the rotation speed of the vehicle 10; accelerator opening θacc, which is the amount of acceleration operation by the driver that indicates the magnitude of the driver's acceleration operation; throttle valve opening θth, which is the opening of an electronic throttle valve driven by a throttle actuator; steering angle θsw and steering direction Dsw of a steering wheel provided on the vehicle 10; longitudinal acceleration Gx and lateral acceleration Gy of the vehicle 10; yaw rate Ryaw, which is the rotation angular velocity of the vehicle 10 about the vertical axis; battery temperature THbat, battery charge / discharge current Ibat, battery voltage Vbat, etc. of the battery 54.

[0020] The electronic control device 80 outputs various command signals (e.g., an engine control command signal Se for controlling the engine 12, an MG control command signal Smg for controlling each of the first electric motor MG1 and the second electric motor MG2, etc.) to each device (e.g., an engine control device 50, an inverter 52, etc.) provided in the vehicle 10.

[0021] In order to realize various controls in the vehicle 10, the electronic control unit 80 is equipped with a power source control means, i.e., a power source control unit 82, an NV suppression control means, i.e., an NV suppression control unit 84, and a turning behavior control means, i.e., a turning behavior control unit 86.

[0022] The power source control unit 82 includes a function for controlling the operation of the engine 12 and a function for controlling the operation of the first electric motor MG1 and the second electric motor MG2, and performs hybrid drive control using the engine 12, the first electric motor MG1, and the second electric motor MG2 using these control functions.

[0023] The power source control unit 82 calculates the amount of driving demanded by the driver for the vehicle 10, for example, by applying the accelerator opening θacc and the vehicle speed V to a driving demand map. The driving demand map is a relationship for calculating the driving demand that is determined and stored in advance experimentally or by design, i.e., a predetermined relationship. The driving demand is, for example, the driving torque Tr required for the vehicle 10, i.e., the required driving torque Trdem [Nm] at the drive wheels 14. In other words, the required driving torque Trdem is the required driving power Prdem [W] at the vehicle speed V at that time. The driving demand may also be the required driving force Frdem [N] at the drive wheels 14, or the like.

[0024] The power source control unit 82 outputs the engine control command signal Se and the MG control command signal Smg to realize the required driving power Prdem, taking into consideration, for example, transmission loss, auxiliary load, and the chargeable / dischargeable power of the battery 54. For example, when the transmission unit 24 is operated as a continuously variable transmission, the engine control command signal Se is a command value for the engine power Pe of the engine 12 that outputs the engine torque Te at the engine rotation speed Ne at that time, taking into consideration, for example, the engine's optimum fuel economy point. The MG control command signal Smg is a command value for the generated power Wg of the first electric motor MG1 that outputs the MG1 torque Tg at the MG1 rotation speed Ng when a command is output as a reaction torque of the engine torque Te. The MG control command signal Smg is a command value for the consumed power Wm of the second electric motor MG2 that outputs the MG2 torque Tm at the MG2 rotation speed Nm when a command for the generated power Wg is output. The engine optimum fuel economy point is predetermined as the engine operating point that provides the best overall fuel economy for the vehicle 10, taking into account factors such as the fuel economy of the engine 12 alone, the charging and discharging efficiency of the battery 54, and the transmission efficiency of the power transmission device 16, i.e., the optimum engine operating point.

[0025] When the required driving power Prdem is in a BEV driving range where the required driving power Prdem is smaller than a predetermined threshold, the power source control unit 82 sets the driving mode of the vehicle 10 to the BEV driving mode. On the other hand, when the required driving power Prdem is in an HEV driving range where the required driving power Prdem is equal to or greater than a predetermined threshold, the power source control unit 82 sets the driving mode of the vehicle 10 to the HEV driving mode. On the other hand, even when the required driving power Prdem is in the motor driving range, the power source control unit 82 establishes the HEV driving mode when, for example, the battery 54 needs to be charged or the engine 12 needs to be warmed up.

[0026] The power source control unit 82 executes start control of the engine 12 to start the engine 12. For example, if the HEV driving mode is established while the engine 12 is stopped, the power source control unit 82 executes start control of the engine 12. The power source control unit 82 starts the engine 12 by, for example, increasing the engine rotation speed Ne using the first electric motor MG1 and igniting the engine when the engine rotation speed Ne reaches or exceeds a predetermined rotation speed at which ignition is possible. In other words, the power source control unit 82 starts the engine 12 by cranking the engine 12 using the first electric motor MG1.

[0027] The power source control unit 82 executes stop control of the engine 12 to stop the engine 12. For example, if the BEV driving mode is established while the engine 12 is operating, the power source control unit 82 executes stop control of the engine 12. The power source control unit 82 stops the engine 12 by stopping the supply of fuel to the engine 12. At this time, the power source control unit 82 may control the MG1 torque Tg to apply to the engine 12 a torque that reduces the engine rotation speed Ne, for example, in order to quickly reduce the engine rotation speed Ne and stop the engine 12.

[0028] The NV suppression control unit 84 performs NV suppression control to suppress NV in the vehicle 10 by changing the operating point of the power source (12, MG2). Examples of NV suppression control include rattle avoidance control, NV deterioration region avoidance control, low rotation muffled noise avoidance control, vibration suppression control during engine start transition, and vibration suppression control during engine stop transition.

[0029] The "rattle noise avoidance control" will now be described. In the power transmission device 16, backlash, or play, exists at the meshing portions between the meshing gears. When the MG2 torque Tm is near or equal to zero, there is a meshing portion where the force pressing the tooth flanks against each other is weakened. When the MG2 torque Tm is near or equal to zero and explosive fluctuations in the engine torque Te are transmitted to this meshing portion, the tooth flanks repeatedly collide and separate from each other, potentially generating a rattle noise (i.e., rattle). The NV suppression control unit 84 performs rattle noise avoidance control, for example, when the MG2 torque Tm is near or equal to zero. In rattle noise avoidance control, the NV suppression control unit 84, for example, changes the engine operating point from the optimal engine fuel efficiency point at a constant power. The NV suppression control unit 84 changes the engine operating point, for example, by increasing the engine rotation speed Ne to a predetermined value or above and decreasing the engine torque Te to a predetermined value or below. This shortens the explosion interval of the engine 12, reducing explosion fluctuations in the engine torque Te and suppressing the excitation torque of the engine 12. In addition, the NV suppression control unit 84 compensates for the decrease in direct torque Td that accompanies a decrease in engine torque Te by increasing the MG2 torque Tm. This increases the force that presses the tooth surfaces of the meshing portions against each other. The rattle avoidance control suppresses or avoids the occurrence of rattle. In the rattle avoidance control, the engine operating point is changed, and the MG2 operating point, which is the operating point of the second electric motor MG2, is also changed. The rattle avoidance control is a control that moves the engine operating point out of a predetermined region where NV is likely to occur.

[0030] The "NV deterioration region avoidance control" will now be described. The power transmission 16 has a predetermined resonant frequency, i.e., natural frequency, based on, for example, mass and torsional rigidity. When engine 12 combustion fluctuations, which are stronger than the force pressing the tooth surfaces together, are transmitted to the meshing portions of the gears in the power transmission 16, the combustion fluctuations act as a forcing force, amplifying the fluctuations and potentially generating gear rattle noise due to drive torsional resonance. This drive torsional resonance occurs when the frequency of the engine 12 combustion fluctuations matches the resonant frequency of the power transmission 16. For this reason, the NV suppression control unit 84 performs NV deterioration region avoidance control, for example, when the engine's optimal fuel economy point falls within a predetermined engine operating point range that generates drive torsional resonance. In NV deterioration region avoidance control, the NV suppression control unit 84, for example, shifts the engine operating point from the engine's optimal fuel economy point by a constant power. NV deterioration region avoidance control suppresses or avoids the occurrence of resonance. NV deterioration region avoidance control changes the engine operating point. NV worsening region avoidance control is a control to move the engine operating point out of a predetermined region where NV is likely to occur.

[0031] The "low rotation booming noise avoidance control" will now be described. The explosion fluctuations of the engine 12 act as a forcing force, and vibrations may be amplified by resonance of the power transmission device 16 that occurs at a specific engine rotation speed Ne. In this case, the amplified explosion fluctuations are transmitted to the suspension via the drive shaft 38, etc., which may cause the vehicle body to vibrate and generate booming noise inside the vehicle. The NV suppression control unit 84 performs low rotation booming noise avoidance control, for example, when the engine operating point is in a predetermined booming noise generation region. In the low rotation booming noise avoidance control, the NV suppression control unit 84, for example, changes the engine operating point from the engine optimum fuel efficiency point at a constant power. The NV suppression control unit 84 changes the engine operating point, for example, by increasing the engine rotation speed Ne by a predetermined rotation amount and decreasing the engine torque Te by a predetermined torque amount. This prevents the engine torque Te from increasing. The low rotation booming noise avoidance control suppresses booming noise caused by the engine torque Te. In the low rotation booming noise avoidance control, the engine operating point is changed. Low-speed muffled noise avoidance control is control that moves the engine operating point outside a predetermined region where NV is likely to occur. Gear rattles are likely to occur when the MG2 torque Tm is near zero, and muffled noise is likely to be lost in background noise at high vehicle speeds. Therefore, muffled noise is likely to become a problem when the MG2 torque Tm is near zero and the vehicle speed is in the low vehicle speed range. Low-speed muffled noise avoidance control may be limited to a region where muffled noise is likely to become a problem, i.e., an unacceptable region.

[0032] The following describes "vibration damping control during engine startup transient." During the engine startup transient, coupled vibrations of the drive and suspension system that occur as the engine 12 starts may be transmitted to the vehicle body. The coupled vibrations of the drive and suspension system transmitted to the vehicle body may be perceived by the driver as a start-up shock of the engine 12. The coupled vibrations of the drive and suspension system include, for example, the vibrations of the drive shaft 38, the vibrations of the damper 20, and the vibrations of the power plant, such as the engine 12 and components housed in the case 18, that are suspended on the vehicle body via mounts. The NV suppression control unit 84 uses the second electric motor MG2 to perform vibration damping control to suppress the coupled vibrations of the drive and suspension system that are transmitted to the vehicle body during the engine startup transient. In the vibration damping control during the engine startup transient, the NV suppression control unit 84 uses feedback control to generate vibrations that are opposite in phase to the coupled vibrations of the drive and suspension system during the engine startup transient, so as to cancel out the coupled vibrations. This suppresses the coupled vibrations of the drive and suspension system. The vibration damping control during the engine startup transition reduces the startup shock of the engine 12. The vibration damping control during the engine startup transition changes the MG2 operating point. The vibration damping control during the engine startup transition is a control that operates the second electric motor MG2 to cancel out the vibration.

[0033] The "vibration damping control during engine stop transition" will now be described. During engine stop transition, coupled vibrations of the drive suspension system that occur as the engine 12 stops may be transmitted to the vehicle body. The coupled vibrations of the drive suspension system transmitted to the vehicle body may be perceived by the driver as a stop shock of the engine 12. The NV suppression control unit 84 uses the second electric motor MG2 to perform vibration damping control that suppresses the coupled vibrations of the drive suspension system that are transmitted to the vehicle body during engine stop transition. The control content of the vibration damping control during engine stop transition is the same as that of the vibration damping control during engine start transition, so a detailed description will be omitted. Vibration damping control during engine stop transition suppresses coupled vibrations of the drive suspension system, thereby suppressing the stop shock of the engine 12.

[0034] The turning behavior control unit 86 performs turning behavior control to control the behavior of the vehicle 10 by changing the torque of the power source (12, MG2) when the vehicle 10 turns.

[0035] It has been experimentally determined that if the pitch behavior is slower than the roll behavior that occurs after the vehicle 10 starts turning, the ground movement seen from the vehicle body will be perceived as unsteady, and a delay will be felt in the turning behavior of the vehicle 10 in response to a turning operation. The roll behavior is, for example, the rotational behavior of the vehicle 10 about a longitudinal axis that passes through the center of the vehicle 10 from front to rear. The pitch behavior is, for example, the rotational behavior of the vehicle 10 about a lateral axis that passes through the center of gravity of the vehicle 10 from left to right, and is the behavior of the vehicle 10 in which the front and rear ends of the vehicle 10 move in approximately vertical directions and in opposite phases.

[0036] Therefore, in the turning behavior control, the turning behavior control unit 86 reduces the time difference of the pitch behavior with respect to the roll behavior at the beginning of the turn. In other words, in the turning behavior control, the turning behavior control unit 86 performs phase advance compensation to advance the phase of the pitch behavior with respect to the roll behavior during the turn. The turning behavior control unit 86 performs phase advance compensation of the pitch behavior at the start of the turn by torque down, which reduces the torque of the power source (12, MG2). The MG2 torque Tm can be reduced with better responsiveness than the engine torque Te. The turning behavior control unit 86 reduces the torque of the power source (12, MG2) by reducing the MG2 torque Tm.

[0037] The turning behavior control is a control that advances the phase of the pitch behavior so as to reduce the phase difference between the roll behavior and the pitch behavior that occurs after the vehicle 10 starts turning by reducing the torque of the power source (12, MG2), for example, the MG2 torque Tm. In this embodiment, this turning behavior control is referred to as line tracing control.

[0038] FIG. 2 is a diagram showing an example of a time chart when line tracing control is activated. In FIG. 2, time tst indicates the time when the vehicle 10 starts turning in response to a turning operation by the driver. After the start of the turn, torque is reduced by controlling the drive torque Tr, that is, line tracing control is performed to reduce the MG2 torque Tm (see time tst and after). The solid line for the drive torque Tr is the drive torque Tr when the line tracing control is not activated, and indicates the drive torque Tr corresponding to the required drive torque Trdem. The dashed line for the drive torque Tr is the drive torque Tr when the line tracing control is activated, and indicates the drive torque Tr reduced by an amount that advances the phase of the pitch behavior relative to the required drive torque Trdem. The roll behavior in the behavior is a normalized version of the roll behavior that occurs after the start of the turn. The pitch behavior in the behavior is a normalized version of the pitch behavior that occurs after the start of the turn, with the solid line being when the control is off and the dashed line being when the control is on. The line tracing control improves the response of the pitch behavior. In other words, line tracing control advances or speeds up the phase of the pitch behavior, thereby reducing the phase difference between the roll behavior and the pitch behavior. This reduces unnecessary fluctuation in the vehicle's line of sight by changing the vehicle's attitude perspective, realizing a turn that feels integrated with the turning operation and improving the turning feeling. In other words, the roll behavior and pitch behavior are synchronized, resulting in a comfortable turning feeling.

[0039] However, when NV suppression control and line tracing control are executed simultaneously, the torque reduction of the power source (12, MG2) due to the line tracing control may cause the operating point of the power source to fall within a region that worsens NV, or the NV suppression control may not be executed appropriately. For example, since the line tracing control reduces the MG2 torque Tm, if the line tracing control is executed while the NV suppression control is being executed, the MG2 torque Tm may be forced to approach zero, which may worsen rattle noise. When the MG2 torque Tm is reduced to reduce the drive torque Tr in the line tracing control, if it is difficult to change the power balance in the battery 54, the engine power Pe is reduced. In this case, if the line tracing control is executed while the NV suppression control is being executed, the engine operating point may be forced within a predetermined region where NV is likely to occur, which may worsen NV. Alternatively, if vibration damping control and line tracing control are executed in an overlapping manner during engine start transition, functional interference between the function of reducing the MG2 torque Tm and the function of vibration damping control by the second electric motor MG2 may cause a start shock or worsen the power balance between the input and output power of the battery 54. The same applies to the case where vibration damping control and line tracing control are executed in an overlapping manner during engine stop transition, which may cause a stop shock or worsen the power balance of the battery 54.

[0040] Therefore, in order to suppress deterioration of NV in the vehicle 10, the electronic control unit 80 further includes a control prohibition determination means, that is, a control prohibition determination unit 88.

[0041] The control prohibition determination unit 88 prohibits the execution of turning behavior control while NV suppression control is being executed. For example, the control prohibition determination unit 88 determines whether NV suppression control is being executed. If the control prohibition determination unit 88 determines that NV suppression control is not being executed, it turns on the line tracing control permission flag and permits, i.e., does not prohibit, the execution of line tracing control. If the control prohibition determination unit 88 determines that NV suppression control is being executed, it turns off the line tracing control permission flag and does not permit, i.e., prohibits, the execution of line tracing control.

[0042] FIG. 3 is a flowchart illustrating the main control operations of the electronic control unit 80, which are executed repeatedly, for example, to suppress deterioration of NV in the vehicle 10.

[0043] 3, each step in the flowchart corresponds to a function of the control prohibition determination unit 88. In step (hereinafter, "step" is omitted) S10, it is determined whether NV suppression control (rattle noise avoidance control, NV deterioration region avoidance control, low-speed booming noise avoidance control, vibration suppression control during engine start transition, vibration suppression control during engine stop transition, etc.) is being executed. If the determination in S10 is negative, this routine is terminated. If the determination in S10 is positive, turning behavior control, for example, line tracing control, is prohibited in S20.

[0044] As described above, according to this embodiment, the execution of turning behavior control is prohibited while NV suppression control is being executed, so that it is possible to prevent the operating point of the power source (12, MG2) from entering a predetermined region where NV is likely to occur due to a change in the torque of the power source (12, MG2), i.e., a change in the operating point of the power source, caused by the turning behavior control, and to prevent the NV suppression control from being performed inappropriately. Therefore, it is possible to prevent the NV in the vehicle 10 from worsening.

[0045] Furthermore, according to this embodiment, the turning behavior control is a control that advances the phase of the pitch behavior so as to reduce the phase difference between the roll behavior and the pitch behavior that occurs after the vehicle 10 starts turning, by reducing the torque of the power source (12, MG2), i.e., line tracing control, so that a turning that feels integrated with the turning operation is realized, improving the turning feeling.

[0046] Furthermore, according to this embodiment, the NV suppression control is control to move the engine operating point out of a predetermined region where NV is likely to occur, or control to operate the second electric motor MG2 to cancel out vibrations, so that NV is appropriately suppressed. Furthermore, by prohibiting the execution of turning behavior control during the execution of NV suppression control, worsening rattle noise is suppressed or avoided, worsening low-speed muffled noise is suppressed or avoided, and starting shock, stopping shock, and deterioration of the power balance of the battery 54 are suppressed or avoided.

[0047] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the present invention can also be applied to other embodiments.

[0048] For example, in the above-described embodiment, line tracing control is exemplified as the turning behavior control, but the present invention is not limited to this. For example, the turning behavior control may be a turning behavior control that sets a target value for the yaw rate at the beginning of a turn, calculates a yaw moment for controlling the yaw rate to the target value, calculates a correction amount for a torque command value for a power source according to the yaw moment, and controls the behavior of the vehicle by changing the torque of the power source so that the torque command value becomes the corrected torque command value. The present invention can also be applied to such turning behavior control.

[0049] In the above-described embodiment, a hybrid vehicle including an engine 12, a transmission 24, a second electric motor MG2, etc., has been described as an example of a vehicle to which the present invention is applied, but the present invention is not limited to this. For example, the present invention can be applied to an engine vehicle that has only an engine as a power source, an electric vehicle that has no engine and only an electric motor as a power source, a parallel or series hybrid vehicle that has an engine and an electric motor as a power source, a so-called plug-in hybrid vehicle that can charge the battery from an external power source such as a charging station or a household power source, etc. In engine vehicles, NV suppression control is performed according to the type of vehicle, such as when rattle avoidance control or vibration suppression control using an electric motor is not available.

[0050] It should be noted that the above is merely one embodiment, and the present invention can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. [Explanation of symbols]

[0051] 10: Vehicle 12: Engine (power source) 14: Drive wheel 24: Transmission section (electric transmission mechanism) 40: Differential mechanism 80: Electronic control device (control device) 84:NV suppression control section 86: Turning behavior control unit 88: Control prohibition determination unit MG1: 1st electric motor MG2: 2nd electric motor (power source)

Claims

1. A control device for a vehicle equipped with a power source, The vehicle includes an engine that functions as the power source, an electric transmission mechanism that has a differential mechanism to which the engine is connected so as to be able to transmit power, and a first electric motor that is connected so as to be able to transmit power to the differential mechanism, and in which the differential state of the differential mechanism is controlled by controlling the operating state of the first electric motor, and a second electric motor that functions as the power source and is connected so as to be able to transmit power to drive wheels, an NV suppression control unit that performs NV suppression control to suppress noise or vibration in the vehicle by changing an operating point represented by the rotational speed and torque of the power source; a turning behavior control unit that performs turning behavior control to control the behavior of the vehicle by changing the torque of the power source when the vehicle is turning; a control prohibition determination unit that prohibits execution of the turning behavior control while the NV suppression control is being executed; Including, A vehicle control device characterized in that the NV suppression control is control to move the operating point of the engine out of a predetermined area where the noise or vibration is likely to occur, or control to operate the second electric motor so as to cancel out the vibration.

2. 2. The vehicle control device according to claim 1, wherein the turning behavior control is a control for advancing the phase of the pitch behavior so as to reduce a phase difference between the roll behavior and the pitch behavior that occurs after the vehicle starts turning by reducing the torque of the power source.

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