JP2013043459A - Controller of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller of a hybrid vehicle that runs by powers from an engine and a motor, the controller being able to stably implementing vehicle stabilizing control, such as ABS control or slip rate control.SOLUTION: The controller (18) of the hybrid vehicle includes a drive wheel condition determining means (22) which determines whether the vehicle is in a slip state or not, a vehicle stabilizing control means (24) which, when the vehicle is determined to be in the slip state, controls an operation state of at least either of an engine (2) and a motor (4), thereby restores the vehicle from the slip state to a normal state, a vehicle stabilizing control determination means (27) which determines whether the vehicle stabilizing control means is in operation or not, and a clutch control means (28) which, when the vehicle stabilizing control means is in operation, sets a clutch (3) to a disconnected state.

Description

  The present invention relates to a technical field of a control device for a hybrid vehicle that travels by transmitting power output from at least one of an engine and a motor to drive wheels via a transmission.

  In recent years, attention has been focused on a hybrid vehicle that travels using at least one of an internal combustion engine such as a gasoline engine or a diesel engine and a motor (electric motor) operable with electric power stored in a battery as a power source. The hybrid vehicle regeneratively drives a motor during deceleration to generate electric power, and the obtained electric power is charged in a battery and stored. Then, by driving the electric motor using the charged electric power, the fuel consumption of the internal combustion engine is reduced and the fuel efficiency is improved.

  In this type of hybrid vehicle, vehicle stability control such as anti-lock brake control (hereinafter referred to as “ABS control”) and slip ratio control is executed in order to restore the vehicle behavior to a stable state when it falls into a slip state. May be. In these controls, when the slip ratio of the drive wheel is detected and it is determined that the detected slip ratio value exceeds a predetermined threshold value set in advance and is in a slip state, in ABS control, a hydraulic brake, an air brake, etc. The vehicle behavior is restored by reducing the braking force of the braking means. On the other hand, in the slip ratio control, a predetermined torque is output from a motor that is a driving power source to prevent the driving wheels from being locked and to recover the vehicle behavior.

  Such vehicle stability control is performed by controlling the braking means and the traveling motor in accordance with a control signal transmitted from a control unit such as an ECU. At this time, extra torque is output from the engine or motor to the drive wheels under vehicle stability control according to the driver request torque (for example, output torque required for the engine or motor according to the amount of depression of the accelerator pedal). If so, there is a problem that the vehicle behavior governed by the vehicle stability control is disturbed. With respect to such a problem, for example, in Patent Document 1, when ABS control which is a kind of vehicle stability control is being executed, the regenerative torque by the motor is reduced (stepwise to zero), thereby improving the braking effectiveness. The reduction is prevented and the vehicle behavior is stabilized.

Japanese Patent Laid-Open No. 10-297462

  As described above, when the vehicle stability control is underway, the vehicle behavior can be stabilized by setting the driver request torque to zero. However, the engine speed in the traveling vehicle varies in various values, and it is realistic to perform engine control so that the output torque of the engine having the engine speed that changes sequentially in this way becomes completely zero. It is difficult. Therefore, even if the driver request torque is set to zero on the ECU side, in actuality, not a little positive or negative torque is output from the engine.

  When the clutch for transmitting the engine power to the drive wheel is connected while the ABS control or the slip ratio control is being executed, even if the engine required torque is set to zero, the above is actually There is a risk that the engine torque as described will be transmitted to the drive wheel side, and the running stability of the vehicle may be reduced. For example, when the engine required torque is set to zero and the torque actually output from the engine is a negative torque, the deceleration torque is added to the drive wheels by the action of the engine brake. Therefore, especially when the traveling road surface is a low μ road or the like, the driving wheels tend to show a tendency to lock, and the traveling stability of the vehicle is lowered. Conversely, when the engine required torque is set to zero and the torque actually output from the engine is a positive torque, the drive torque acts on the vehicle even though the engine required torque is zero. As a result, the deceleration force of the vehicle becomes insufficient. As a result, the braking performance is deteriorated, for example, the braking distance becomes long, and the running stability of the vehicle is lowered.

  The present invention has been made in view of the above problems, and is a hybrid vehicle control device capable of stably performing vehicle stability control such as ABS control and slip ratio control in a hybrid vehicle that travels by power from an engine and a motor. The purpose is to provide.

  In order to solve the above problems, the hybrid vehicle control device according to the present invention is provided with a clutch between the engine and the motor, and travels by transmitting the power generated at least one of the engine and the motor to the drive wheels. A control device for a hybrid vehicle that performs determination of whether or not the drive wheel is in a slip state, and the drive wheel state determination unit determines that the drive wheel is in a slip state. Sometimes, by controlling the operating state of at least one of the engine and the motor, a vehicle stability control means for recovering the driving wheel from the slip state, and whether or not the vehicle stability control means is operating is determined. Vehicle stability control determining means, and the vehicle stability control determining means determines that the vehicle stability control means is operating. In, characterized in that a clutch control means for setting the clutch in a disconnected state.

  According to the present invention, when the vehicle stability control is activated due to the drive wheel falling into the slip state, the clutch is set to the disengaged state so that the output torque of the engine is not transmitted to the drive wheel side. In particular, it is difficult to accurately control the running engine torque to zero based on the driver's requested torque. By thus disengaging the clutch, the engine torque is mechanically transmitted to the drive wheels. Can be prevented. Thereby, it is possible to effectively prevent the stability of the vehicle behavior from being lost by transmitting the output torque of the engine during the operation of the vehicle stability control such as ABS control or slip ratio control.

  As one aspect of the present invention, the vehicle stability control means is configured such that the slip ratio of the drive wheel becomes a target slip ratio when the drive wheel state determination means determines that the drive wheel is in a slip state. In addition, it is preferable that the driving wheel is recovered from the slip state by performing ABS control for controlling the braking torque of the driving wheel, and the output torque of the motor is set to zero. In this aspect, the vehicle stability control is so-called ABS control, and the influence received from the engine by actually disengaging the clutch as described above under vehicle stability control (actually when the driver request torque is set to zero). The influence of the torque output from the engine) can be eliminated, and the control accuracy of the vehicle stability control can be improved. On the other hand, since the motor has better controllability than the engine, the output torque can be easily set to zero. As a result, the vehicle stability control can be accurately performed without being affected by the engine or the motor, and the vehicle behavior can be quickly stabilized from the slip state.

  As another aspect of the present invention, the vehicle stability control means is configured such that when the drive wheel state determination means determines that the drive wheel is in a slip state, the slip ratio of the drive wheel becomes a target slip ratio. As described above, the driving wheel may be recovered from the slip state by applying the driving torque or the regenerative torque to the motor and performing the slip ratio control for suppressing the slip state of the driving wheel. In this aspect, the vehicle stability control is a so-called slip ratio control, and the influence of the engine is eliminated and the control accuracy of the vehicle stability control is improved by disengaging the clutch as described above under the vehicle stability control. can do. On the other hand, by applying drive torque or regenerative torque from a motor with excellent controllability, the vehicle behavior in the slip state can be recovered.

  The power of the engine is transmitted to the drive wheels via a dual clutch transmission, and the dual clutch transmission includes a first power transmission system capable of transmitting power of the engine and the motor to the drive wheels, A first clutch provided between the engine and the motor of the first power transmission system; a second power transmission system capable of transmitting the power of the engine to the drive wheels; and the second power transmission system. A second clutch provided to transmit power to the drive wheel via either the first power transmission system or the second power transmission system, and the clutch control means is configured to control the vehicle stability control. The first clutch and the second clutch may be set to a disengaged state when the determination means determines that the vehicle stability control means is operating. . This aspect is a case where the present invention is applied to a hybrid vehicle equipped with a dual clutch transmission, which has been attracting attention in recent years because there is little energy loss during shifting. Even in this case, by setting the first clutch and the second clutch to the disengaged state, it is mechanically prevented that the engine torque is transmitted to the drive wheel side when the vehicle stability control is activated. As a result, the vehicle behavior can be stabilized.

  According to the present invention, when the vehicle stability control is activated due to the drive wheel falling into the slip state, the clutch is set to the disengaged state so that the output torque of the engine is not transmitted to the drive wheel side. In particular, it is difficult to accurately control the running engine torque to zero based on the driver's requested torque. By thus disengaging the clutch, the engine torque is mechanically transmitted to the drive wheels. Can be prevented. Thereby, it is possible to effectively prevent the stability of the vehicle behavior from being lost by transmitting the output torque of the engine during the operation of the vehicle stability control such as ABS control or slip ratio control.

1 is a block diagram conceptually showing an overall configuration of a hybrid electric vehicle according to a first embodiment. It is a graph which shows transition of the brake depression force by the depression amount of the brake pedal at the time of ABS control action | operation, the slip ratio of a driving wheel, and a mechanical brake. It is a graph which shows transition of the slip ratio and motor output torque in slip ratio control. It is a functional block diagram of ECU. It is a flowchart figure which shows the control content of a hybrid vehicle in case ABS control is operated as vehicle stability control. It is a flowchart figure which shows the control content in the hybrid vehicle by which slip ratio control is operated as vehicle stability control. It is a block diagram which shows notionally the whole structure of the hybrid vehicle which concerns on 2nd Example.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.

(First embodiment)
FIG. 1 is a block diagram conceptually showing the overall structure of the hybrid vehicle 1 according to the first embodiment. The hybrid vehicle 1 is a parallel hybrid electric vehicle having an engine 2 and a motor 4 as driving power sources. When the output shaft of the engine 2 and the rotating shaft of the motor 4 are connected via the clutch 3 and the transmission of power is switched according to the connection state of the clutch 3, and the clutch 3 is connected, When the engine 2 or the engine 2 and the motor 4 are used together as a power source and the clutch 3 is disengaged, the motor 4 is used as the power source and the transmission 5 is attached to the propeller shaft 6 at a predetermined gear ratio. Communicated. The motive power transmitted to the propeller shaft 6 is driven by the drive wheels 9 via the differential device 7 and the drive shaft 8 so that the hybrid vehicle 1 travels.

  The engine 2 is an internal combustion engine that functions as one of the power sources of the hybrid vehicle 1, and may be a gasoline engine or a diesel engine. In the case of a gasoline engine, a so-called direct injection type gasoline engine that directly injects fuel into the combustion chamber may be used.

  The clutch 3 is a power transmission mechanism that switches a connection state between the output shaft of the engine 2 and the rotation shaft of the motor 4. When the clutch 3 is in the connected state, the output torques of the engine 2 and the motor 4 are both transmitted to the drive wheel 9 side. On the other hand, when the clutch 3 is in the disengaged state, the output torque of the engine 2 is not transmitted to the motor 4 side, and therefore, only the output torque from the motor 4 is transmitted to the drive wheel 9 side.

  The motor 4 is an electric motor including a stator (stator) that generates a predetermined magnetic field and a rotor (rotor) that rotates so as to cross the magnetic field generated by the stator. The motor 4 is driven by power supplied from the battery 11 via the inverter 10 to generate drive torque, and functions as one of the power sources of the hybrid electric vehicle 1. When the motor 4 is regeneratively driven, it generates electric power by generating regenerative energy and also functions as a regenerative brake by generating braking torque. The electric power generated by the motor 4 is DC converted by the inverter 10 and then charged to the battery 11.

  The transmission 5 is a manual transmission or an automatic transmission having a plurality of shift stages, and the shift stages may be changed stepwise or continuously.

  A wheel speed sensor 12 is provided on each drive wheel 9 provided on the left and right of the hybrid vehicle 1. The wheel speed detected by the wheel speed sensor 12 is transmitted to the ECU 18 and converted into the slip ratio of each drive wheel 9. The slip rate conversion method is well known and will not be described. However, the hybrid vehicle 1 performs vehicle stability control such as ABS control and slip rate control based on the converted slip rate, thereby stabilizing the vehicle behavior. I am trying.

  The battery 11 is a storage battery composed of secondary battery cells that store electric power for powering the motor 4. The battery 11 is charged with DC power in advance, and the DC power output at the time of discharging is AC converted by the inverter 10 and consumed for powering driving of the motor 4. On the other hand, when the motor 4 is regeneratively driven, AC power generated by the motor 4 is converted into DC by the inverter 10 and the battery 11 is charged.

  The upper limit charge amount and the lower limit charge amount of the battery 11 are defined in advance by various conditions such as the type and number of secondary battery cells constituting the battery 11. The charge amount of the battery is controlled by the electronic device so as to be within the range of the upper limit charge amount to the lower limit charge amount, and by preventing the battery 11 from falling into an overcharge / overdischarge state, the life of the battery 11 can be extended. It is illustrated.

  When the clutch 3 is in the connected state, the output shaft of the engine 2 is mechanically connected to the rotating shaft of the motor 4. At this time, when the motor 4 is driven by power running, output torque from both the engine 2 and the motor 4 is transmitted to the drive wheels 9. That is, a part of the torque for driving the drive wheels 9 is supplied from the engine 2 and the rest is supplied from the motor 4. Further, when the charge amount of the battery 11 decreases during traveling, the motor 4 is regeneratively driven using the remaining output torque of the engine 2 while driving the drive wheels 9 using a part of the output torque of the engine 2. The battery 11 can be charged with the generated power.

  On the other hand, when the clutch is in the disconnected state, the output shaft of the engine 2 is mechanically disconnected from the rotating shaft of the motor 4. At this time, when the motor 4 is driven by power running, the output torque from the engine 2 is not transmitted to the drive wheels 9, but only the output torque from the motor 4 is transmitted. That is, the hybrid electric vehicle 1 travels exclusively by driving the motor 4 using the electric power stored in the battery 11.

  The brake pedal 13 transmits the amount of depression by the driver to the ECU 18, and the ECU 18 operates the mechanical brake 14 provided on each drive wheel 9 based on the control signal to generate a braking torque and decelerate the hybrid vehicle 1. . Particularly in this embodiment, the mechanical brake 14 is a hydraulically controlled brake, and the braking torque can be controlled by applying a hydraulic pressure corresponding to a control signal from a braking ECU (not shown) by a hydraulic control mechanism (not shown). It is configured. The hydraulic value applied to the mechanical brake 14 is detected by a hydraulic sensor (not shown) and transmitted to the ECU 18 to be used for various controls.

  The amount of depression by the driver of the accelerator pedal 16 is also transmitted to the ECU 18, and the ECU 18 controls the engine 2 and the motor 4 which are power sources based on the control signal to accelerate the vehicle.

  The ECU 18 operates the hybrid vehicle 1 based on detection values of various sensors provided in the hybrid vehicle 1 and information on acceleration / deceleration requests from the driver obtained from the accelerator pedal 16 and the brake pedal 13 (each depression amount). It is an electronic control unit that controls the whole. For example, the ECU 18 controls the torque to be output from the engine 2 based on the driver request torque calculated based on the various information described above, or controls the inverter 10 to power drive or regenerate the motor 4. In addition, the ECU 18 performs various controls necessary for traveling of the hybrid vehicle 1 such as checking the remaining charge of the battery 11.

  The ECU 18 is an electronic control unit that includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and performs various controls described later according to a control program stored in the ROM. Is configured to be able to execute. The physical, mechanical and electrical configurations of these various controls are not limited to this.

  In the hybrid vehicle 1 according to the present embodiment, ABS control and slip ratio control are performed as vehicle stability control. Here, the ABS control and the slip ratio control will be specifically described.

  FIG. 2 is a graph showing changes in the slip ratio S of the drive wheels 9, the amount of depression of the brake pedal 13, and the brake braking force by the mechanical brake 14 during the ABS control operation. The slip ratio of the drive wheel 9 shown in FIG. 2A is a value obtained by converting the wheel speed detected by the wheel speed sensor 12 by the ECU 18. FIG. 2B shows the depression amount detected by the ECU 18 from the brake pedal 13. The brake braking force shown in FIG. 2C indicates a braking torque value that is finally generated by the mechanical brake 14 by a control signal from a braking ECU (not shown).

  First, it is assumed that the hybrid vehicle 1 is in a steady state where the vehicle travels at a constant speed, and a situation in which the driver attempts to decelerate the hybrid vehicle 1 by depressing the brake pedal 13 at time t0. In this deceleration operation, the driver depresses the depression amount of the brake pedal 13 so as to gradually increase from time t0 to time t1, and keeps a constant value after time t1. At this time, since the slip ratio S is less than the predetermined threshold value S1 at times t0 to t1, the ABS control does not operate, and the braking torque from the mechanical brake 14 gradually increases according to the depression amount of the brake pedal 13. To increase.

  When the time t1 is reached, the slip ratio S exceeds the predetermined threshold S1, indicating that the hybrid vehicle 1 has fallen into a slip state. Then, the ABS control is activated, and the braking torque is controlled by a braking ECU (not shown) as follows.

  After the time t1, the amount of depression of the brake pedal 13 is constant, but if the braking torque is maintained with the slip ratio S being high, the driving wheel 9 exhibits a tendency to lock and the vehicle behavior cannot be recovered. Therefore, the braking ECU (not shown) alleviates the locking tendency of the drive wheels 9 by reducing the braking torque of the mechanical brake 14 after the slip ratio S exceeds the predetermined threshold S1 regardless of the depression amount of the brake pedal 13. Then, the slip ratio S is reduced. Note that the braking torque of the mechanical brake 14 is controlled with a slight delay from the slip ratio S. When the slip rate S falls below the predetermined threshold S1 at time t2, the braking torque is controlled so that the braking force corresponding to the depression amount of the brake pedal 13 is obtained again.

  After the time t2, the slip ratio S is greater than the predetermined threshold value S1 at the times t3 to t4 and t5 to 6, so that the braking torque is reduced by a braking ECU (not shown) in these periods as well. By controlling, the vehicle behavior is recovered.

  As described above, in the ABS control, the vehicle behavior is stabilized by reducing the braking torque by a braking ECU (not shown). At this time, in order to stabilize the vehicle behavior by the braking torque control by the braking ECU (not shown), it is preferable that the output torque from the engine 2 or the motor 4 is zero. Therefore, in the hybrid vehicle 1 according to the present embodiment, the ECU 18 performs control so that the output torque from the engine 2 and the motor 4 becomes zero during the operation of the ABS control (however, as will be described later, the engine 2). It is technically difficult to make the output torque of zero exactly zero, and in fact, a positive or negative torque is output in a small amount).

  FIG. 3 is a graph showing the transition of the slip ratio of the drive wheel 9 and the output torque of the motor 4 in the slip ratio control. The slip rate shown in FIG. 3A is a value obtained by converting the wheel speed detected by the wheel speed sensor 12 installed in each drive wheel 9 by the ECU 18 as in FIG. 2A. I use it. The motor output torque shown in FIG. 3B is a control value by the ECU 18.

  First, when the hybrid vehicle 1 starts decelerating after releasing the accelerator from a state where the driver depresses the accelerator pedal 16 by a certain amount, the slip ratio S increases due to the road surface approaching the low μ road at time t0. Assume the situation. When the slip ratio S increases from time t0 to time t1 and exceeds the predetermined threshold value S1 at time t1, slip ratio control is activated when the hybrid vehicle 1 falls into a slip state. At this time, since the drive wheels 9 of the hybrid vehicle 1 show a locking tendency, the ECU 18 switches the motor 4 to the power running driving or reduces the regenerative driving so as to alleviate the locking tendency. As a result, the slip ratio S decreases, and when it falls below the predetermined threshold value S1 at time t2, the drive control of the motor 4 is returned to the normal regenerative drive. Even after time t2, since the slip ratio S becomes larger than the predetermined threshold value S1 at times t3 to t4 and t5 to 6, the output torque of the motor 4 is controlled by the ECU 18 in the same manner as described above. Thus, recovery of the vehicle behavior is achieved.

  Next, a specific operation of the hybrid vehicle 1 configured as described above will be described. FIG. 4 is a functional block diagram of the ECU 18.

  The wheel speed detected by the wheel speed sensor 12 is input to the slip ratio conversion unit 21 of the ECU 18 so that the corresponding slip ratio S is calculated. The slip ratio S is transmitted to the drive wheel state determination unit 22 and is compared with a predetermined threshold value S1 stored in advance in the storage unit 23 to determine whether the hybrid vehicle 1 is in a slip state. The vehicle stability control unit 24 performs vehicle stability control (ABS control or slip rate control) according to the determination result in the drive wheel state determination unit 22.

  The output torque calculation unit 25 calculates the output torque to the engine 2 and the motor 4 based on the depression amount of the accelerator pedal 16 and the command from the vehicle stability control unit 24, and controls the output torque of the engine 2 and the motor 4. I do. The braking torque calculation unit 26 calculates the braking torques of the engine 2 (engine brake) and the motor 4 (regenerative brake) based on the depression amount of the brake pedal 13 and the command from the vehicle stability control unit 24, respectively. The braking torque control of the engine 2 and the motor 4 is performed. At this time, the vehicle stability control determination unit 27 determines whether or not the vehicle stability control unit 24 is operating, and the clutch control unit 28 determines whether the clutch 3 is operated according to the operating state and ABS operation information from a braking ECU (not shown). Switch and control connection status.

  FIG. 5 is a flowchart showing the control contents of the hybrid vehicle 1 when the ABS control is operated as the vehicle stability control.

  The ECU 18 determines whether or not the ABS control is operating in the vehicle stability control unit 24 (step S101). When the ABS control is not in operation (step S101: NO), the clutch engagement state, engine operation state, and motor drive state are controlled as usual (step S105).

  On the other hand, when the ABS control is operating (step S101: YES), the vehicle ECU 18 determines whether or not the clutch 3 is in an engaged state by accessing the clutch control unit 28 (step S102). As described above, when the vehicle is under ABS control, the output torque requested from the output torque calculation unit 25 to the engine 2 is set to zero, thereby stabilizing the vehicle behavior. However, the engine speed in the traveling vehicle changes in various values, and it is a reality to perform engine control so that the output torque of the engine 2 having the engine speed that sequentially changes in this way becomes completely zero. Is difficult. For this reason, even when the output torque from the engine 2 is set to zero on the output torque calculation unit 25 side, in actuality, not a little positive or negative torque is output from the engine 2.

  If the clutch 3 is in the engaged state at this time, the output torque from the engine 2 is transmitted to the drive wheel 9 side, and the controllability of the ABS control is deteriorated, and the stability of the vehicle behavior may be deteriorated. There is. Therefore, when the clutch 3 is in the engaged state during the operation of the ABS control (step S102: YES), the clutch control unit 28 forcibly switches the clutch 3 to the disengaged state, so that the output torque from the engine 2 is increased to the driving wheel. Transmission to the 9 side is prevented (step S103). By disengaging the clutch 3 in this manner, it is possible to prevent the output torque from being mechanically transmitted from the engine 2 to the drive wheels 9, so that the stability of the vehicle behavior is effectively lost. Can be prevented.

  On the other hand, when the clutch 3 is in the disengaged state during the operation of the ABS control (step S102: NO), the disengaged state of the clutch 3 is continued (step S104). At this time, the operating state of the engine 2 is set to an idling state, and the driving state of the motor 4 is set to a zero torque state.

  FIG. 6 is a flowchart showing the control contents in the hybrid vehicle 1 in which the slip ratio control is operated as the vehicle stability control. Here, steps S201 and S202 in FIG. 6 are the same as steps S101 and S102 in FIG.

  During the operation of the slip ratio control, the drive torque or the regenerative torque is applied to the motor 4 so that the slip ratio of the drive wheel 9 becomes the target slip ratio, and the slip state of the drive wheel 9 is suppressed. At this time, the output torque calculation unit 25 performs control so that the output torque from the engine 2 becomes zero, but actually, as described above, not a little positive or negative torque is output from the engine 2. If the clutch 3 is in the engaged state at this time, the output torque from the engine 2 is transmitted to the drive wheel 9 side, and the controllability of the slip ratio control is deteriorated and the stability of the vehicle behavior is deteriorated. There is a fear. Therefore, when the clutch 3 is in the connected state during the operation of the slip ratio control (step S202: YES), the clutch control unit 28 forcibly switches the clutch 3 to the disconnected state, thereby driving the output torque from the engine 2. Transmission to the wheel 9 side is prevented (step S203).

  Since the clutch 3 is in the disengaged state in this way, the output torque from the engine 2 can be prevented from being mechanically transmitted to the drive wheels 9, so that it is effective that the stability of the vehicle behavior is impaired. Can be prevented. On the other hand, when the clutch 3 is in the disconnected state during the operation of the slip ratio control (step S202: NO), the disconnected state of the clutch 3 is continued (step S204). At this time, the operating state of the engine 2 is set to an idling state, and the driving state of the motor 4 is controlled according to slip ratio control as shown in FIG.

(Second embodiment)
Next, an example in which the present invention is applied to a hybrid vehicle 1 ′ having a dual clutch transmission 30 having a plurality of clutches will be described. FIG. 7 is a block diagram conceptually showing the overall structure of the hybrid vehicle 1 ′ according to the second embodiment. Note that portions common to the first embodiment are denoted by common reference numerals, and detailed description thereof is omitted as appropriate.

  The dual clutch transmission 30 has a first power transmission system and a second power transmission system as a path for transmitting the output torque of the engine 2 to the drive wheel 9 side. FIG. 7A illustrates the case where the power of the engine 2 is transmitted to the drive wheels 9 via the first power transmission system. The first power transmission system includes a first clutch 31 for switching the connection state between the engine 2 and the drive wheels 9, a motor 4 that functions as a driving power source together with the engine 2, and an even-numbered speed stage (second speed, And a transmission gear group 30a in charge of 4th speed and 6th speed).

  FIG. 7B illustrates a case where the power of the engine 2 is transmitted to the drive wheels 9 via the second power transmission system. The second power transmission system includes a second clutch 32 for switching the connection state between the engine 2 and the drive wheel 9, and a transmission gear group 30 b in charge of odd gears (first speed, third speed, and fifth speed). Consists of.

  As shown in FIG. 7A, when the power of the engine 2 is transmitted to the drive wheel 9 side via the first power transmission system, the even-numbered speed stage 30a is connected. In the odd-numbered shift stage 30b of the power transmission system, a shift stage to be shifted at the next timing is selected (pre-shifted) in advance. Thereby, in the dual clutch transmission 30, the time required for the shift operation can be shortened, and energy loss such as torque loss can be reduced. As described above, the hybrid vehicle 1 ′ switches either the first power transmission system or the second power transmission system by alternately switching the connection state of the first clutch 31 and the second clutch 32 to connection / disconnection. Travel through while selecting the appropriate gear.

  At this time, when vehicle stability control such as ABS control or slip ratio control is activated, the first clutch 31 and the second clutch 32 are set so that the behavior of the drive wheels 9 is not affected by the engine 2 side. Forced switch to disconnected state. That is, in the hybrid vehicle 1 ′ of the present embodiment, either the first clutch 31 or the second clutch 32 is basically in a connected state during traveling (except for a part during deceleration), but the vehicle is stable. By switching to the disconnected state at the timing when the control is activated, the engine 2 is mechanically isolated from the drive wheel 9 side to ensure the controllability of the vehicle stability control.

  As in the first embodiment, when the vehicle stability control to be operated is ABS control, the engine 2 is idling, the output torque of the motor 4 is set to zero, and the vehicle stability control is slip ratio control. Only the output torque of the engine 2 is set to the idling state.

  As described above, according to the present embodiment, the clutch 3 is set to the disconnected state so that the engine torque is not transmitted to the drive wheel 9 side when the vehicle stability control is activated due to the slip state. Although it is difficult to control the engine torque to zero by the driver request torque, the engine torque can be prevented from being mechanically transmitted to the drive wheels 9 by disengaging the clutch 3 in this manner. Thereby, it is possible to effectively prevent the stability of the vehicle behavior from being impaired by transmitting the engine torque during the operation of the vehicle stability control such as the ABS control or the slip ratio control.

  INDUSTRIAL APPLICABILITY The present invention can be used for a control device for a hybrid vehicle that travels by transmitting power output from at least one of an engine and a motor to drive wheels via a transmission.

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 2 Engine 3 Clutch 4 Motor 5 Transmission 6 Propeller shaft 7 Differential device 8 Drive shaft 9 Drive wheel 10 Inverter 11 Battery 12 Wheel speed sensor 13 Brake pedal 14 Mechanical brake 16 Accelerator pedal 18 ECU
DESCRIPTION OF SYMBOLS 21 Slip ratio conversion part 22 Drive wheel state determination part 23 Storage part 24 Vehicle stability control part 25 Output torque calculation part 26 Braking torque calculation part 27 Vehicle stability control determination part 28 Clutch control part 30 Dual clutch transmission 31 1st clutch 32 1st clutch 2 clutch

Claims (4)

A control device for a hybrid vehicle, in which a clutch is provided between an engine and a motor, and travels by transmitting power generated at least one of the engine and the motor to drive wheels,
Driving wheel state determining means for determining whether or not the driving wheel is in a slip state;
When the driving wheel state determining means determines that the driving wheel is in a slip state, the vehicle stability is achieved by controlling the driving state of at least one of the engine and the motor to recover the driving wheel from the slip state. Control means;
Vehicle stability control determining means for determining whether or not the vehicle stability control means is operating;
A hybrid vehicle control device comprising: clutch control means for setting the clutch to a disengaged state when the vehicle stability control determination means determines that the vehicle stability control means is operating.   The vehicle stability control means is configured such that when the driving wheel state determination means determines that the driving wheel is in a slip state, the braking torque of the driving wheel is set so that the slip ratio of the driving wheel becomes a target slip ratio. The hybrid vehicle control device according to claim 1, wherein the driving wheel is recovered from a slip state by performing ABS control for controlling the motor, and the output torque of the motor is set to zero.   The vehicle stability control means applies a drive torque or regeneration to the motor so that the slip ratio of the drive wheel becomes a target slip ratio when the drive wheel state determination means determines that the drive wheel is in a slip state. The control apparatus for a hybrid vehicle according to claim 1, wherein the drive wheel is recovered from the slip state by applying slip ratio control that suppresses the slip state of the drive wheel by applying torque. The power of the engine and the motor is transmitted to the drive wheel via a dual clutch transmission,
The dual clutch transmission includes a first power transmission system capable of transmitting power of the engine and the motor to the drive wheels, and a first clutch provided between the engine and the motor of the first power transmission system. And a second power transmission system capable of transmitting the power of the engine to the drive wheels, and a second clutch provided in the second power transmission system, the first power transmission system and the first power transmission system Power is transmitted to the drive wheel via one of the power transmission systems of 2;
The clutch control means sets the first clutch and the second clutch to a disengaged state when the vehicle stability control determination means determines that the vehicle stability control means is operating. The control device for a hybrid vehicle according to any one of claims 1 to 3.

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