JP2010167803A - Controller for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a hybrid vehicle, which suppresses input rotation speed of a transmission from being excessively reduced during torque-down due to a slip of a driving wheel, and suppresses resultant engine stop and generation of reverse rotation of the engine and a motor. <P>SOLUTION: In the controller for a hybrid vehicle, an engine Eng and a motor generator MG are connected to an input shaft IPS side of an automatic transmission AT. A traction controller 30 performs torque-down upon detection of a slip of the driving wheel, and an integrated controller 10 performs torque distribution between the engine Eng and the motor generator MG so that total input torque of the engine Eng and the motor generator MG is not smaller than a torque threshold value at torque-down when a gear stage of the automatic transmission AT is a gear stage where a one-way clutch is interposed, during the torque-down. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control apparatus for a hybrid vehicle that has an engine and a motor as drive sources and executes torque-down processing for reducing drive torque output to drive wheels when drive wheels slip.

  Conventionally, in a control device for a hybrid vehicle, a control device that reduces the torque between the engine and the motor and suppresses the slip of the drive wheel when the drive wheel slips is known from, for example, Patent Document 1 or the like. .

JP 2000-274269 A

  However, in a conventional hybrid vehicle control apparatus, when this control is performed, in a system using a stepped transmission, if the torque reduction amount is large in the gear stage where the one-way clutch is interposed, the input rotation of the transmission There has been a problem that the number may decrease, and the engine may stop or reverse rotation may occur in the engine and the motor. In particular, when a motor generator capable of generating power is used as the motor and power is generated in the HEV mode in which the engine and the motor generator are directly connected, such a problem is likely to occur because the motor generator has a negative torque. .

  The present invention has been made paying attention to the above-mentioned problem, and suppresses an excessive decrease in the input rotational speed of the transmission when executing the torque-down process accompanying the drive wheel slip, and causes the engine to stop. Another object of the present invention is to provide a hybrid vehicle control apparatus that can suppress the occurrence of reverse rotation of the engine and the motor.

  In order to achieve the above object, in the hybrid vehicle control device of the present invention, when the gear stage of the transmission is a gear stage with a one-way clutch interposed, when the torque reduction process accompanying the drive wheel slip is performed, the transmission Torque-down limiting means for distributing torque between the engine and the motor is provided so that the total input torque of the engine and motor to the input shaft of the engine does not become a value smaller than a preset torque-down torque threshold. A control device for a hybrid vehicle is provided.

  In the control apparatus for a hybrid vehicle of the present invention, when a drive wheel slip occurs at the time of starting acceleration or the like, the torque control means executes a torque down process to reduce the input torque to the transmission. This reduces the slip amount of the drive wheel.

  Furthermore, when such a torque-down process is performed, if the gear stage of the transmission is a gear stage with a one-way clutch interposed, the torque-down limiting means inputs the total input from the engine and motor to the transmission. Torque is distributed between the engine and the motor so that the torque does not become smaller than a preset torque-down torque threshold.

  Therefore, when the torque reduction process associated with the drive wheel slip is executed, it is possible to suppress an excessive decrease in the input rotational speed of the transmission, and it is possible to suppress the engine stop and the reverse rotation of the engine and the motor caused by this.

1 is an overall system diagram showing an FR hybrid vehicle (an example of a hybrid vehicle) by rear wheel drive to which a hybrid vehicle control device of Embodiment 1 is applied. It is a control block diagram which shows the arithmetic processing performed in the integrated controller 10 of the FR hybrid vehicle to which the control apparatus of Example 1 was applied. It is a figure which shows the target drive force map used when calculating the target drive force tFo0 with the integrated controller 10 of the FR hybrid vehicle to which the control apparatus of Example 1 was applied. It is a figure which shows the EV-HEV selection map used when performing the mode selection process with the integrated controller 10 of the FR hybrid vehicle to which the control apparatus of Example 1 is applied. It is a figure which shows the target charging / discharging amount map used when performing battery charging / discharging process with the integrated controller 10 of the FR hybrid vehicle to which the control apparatus of Example 1 was applied. 1 is a skeleton diagram illustrating an example of an automatic transmission AT used in Embodiment 1. FIG. FIG. 6 is a collinear diagram illustrating a first-speed torque transmission state in the automatic transmission AT used in Embodiment 1, and (a) illustrates a state in which positive torque is input to the input shaft IPS of the automatic transmission AT. (B) shows a state in which negative torque is input to the input shaft IPS of the automatic transmission AT. 4 is a flowchart illustrating a flow of processing of drive wheel slip control by the control device of the first embodiment. In calculating the target engine torque in the operating point command unit 400 of the control apparatus of the first embodiment, it is selected that torque reduction by fuel cut and torque reduction by ignition timing adjustment are selected according to the battery charge amount SOC. It is a characteristic view which shows F / C non-permission SOC threshold value and F / C permission SOC threshold value which are demonstrated. FIG. 3 is a block diagram illustrating a configuration for determining torque distribution of an engine Eng and a motor generator MG in the control device of the first embodiment. 6 is a time chart showing an operation example in the case where a driver performs a sudden acceleration operation and a drive wheel slip occurs from a state where power is generated in the HEV mode while the vehicle is stopped in the control device of the first embodiment.

    Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  In the control apparatus for a hybrid vehicle of the present embodiment, an engine (Eng) and a motor (MG) are connected to the input shaft (IPS) side of a transmission (AT) having a gear stage in which a one-way clutch is interposed. A control apparatus for a hybrid vehicle, wherein when the slip detection means detects drive wheel slip, torque control means for executing torque down processing for reducing drive wheel slip by reducing input torque of the transmission (AT) (30) and the engine (Eng) to the input shaft (IPS) when the gear stage of the transmission (AT) is a gear stage with the one-way clutch interposed at the time of execution of the torque reduction process. And the motor (MG) so that the total input torque does not become smaller than a preset torque-down torque threshold. It is a control apparatus for a hybrid vehicle according to claim which includes an engine torque reduction limiting means for performing torque distribution (Eng) and the motor (MG) (10).

  A control apparatus for a hybrid vehicle according to a first embodiment of the best mode for carrying out the invention will be described with reference to FIGS.

  FIG. 1 is an overall system diagram showing a rear-wheel drive FR hybrid vehicle (an example of a hybrid vehicle) to which the control device of the first embodiment is applied.

  As shown in FIG. 1, the drive system of the FR hybrid vehicle in the first embodiment includes an engine Eng, a flywheel FW, a first clutch CL1, a motor generator MG, a second clutch CL2, and an automatic transmission AT. , A propeller shaft PS, a differential DF, a left drive shaft DSL, a right drive shaft DSR, a left rear wheel RL (drive wheel), and a right rear wheel RR (drive wheel). Note that FL is the left front wheel and FR is the right front wheel.

  The engine Eng is a gasoline engine or a diesel engine, and performs engine start control, engine stop control, and throttle valve opening control based on an engine control command from the engine controller 1. The engine output shaft is provided with a flywheel FW.

  The first clutch CL1 is a clutch interposed between the engine Eng and the motor generator MG, and is based on the first clutch control command from the first clutch controller 5 and is generated by the first clutch hydraulic unit 6. Engagement / release including half clutch state is controlled by one clutch control oil pressure. As the first clutch CL1, for example, a dry single-plate clutch whose engagement / release is controlled by a hydraulic actuator 14 having a piston 14a is used.

  Motor generator MG is a synchronous motor generator in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator, and three-phase alternating current generated by inverter 3 is applied based on a control command from motor controller 2. Is controlled. The motor generator MG can operate as an electric motor that is driven to rotate by receiving power supplied from the battery 4 (hereinafter, this state is referred to as “powering”), and the rotor receives rotational energy from the engine Eng or driving wheels. , The battery 4 can be charged by functioning as a generator that generates electromotive force at both ends of the stator coil (hereinafter, this operation state is referred to as “regeneration”). The rotor of motor generator MG is connected to input shaft IPS of automatic transmission AT via a damper.

  The second clutch CL2 is a clutch interposed between the motor generator MG and the left and right rear wheels RL, RR, and is generated by the second clutch hydraulic unit 8 based on the second clutch control command from the AT controller 7. The fastening / release including slip fastening and slip releasing is controlled by the control hydraulic pressure. As the second clutch CL2, for example, a wet multi-plate clutch or a wet multi-plate brake capable of continuously controlling the oil flow rate and hydraulic pressure with a proportional solenoid is used. The first clutch hydraulic unit 6 and the second clutch hydraulic unit 8 are incorporated in an AT hydraulic control valve unit CVU attached to the automatic transmission AT.

  The automatic transmission AT is a stepped transmission that automatically switches, for example, stepped gears such as forward 5 speed / reverse 1 speed according to vehicle speed, accelerator opening, etc., and the second clutch CL2 includes: It is not newly added as a dedicated clutch, but an optimum clutch or brake arranged in the torque transmission path is selected from a plurality of frictional engagement elements that are engaged at each gear stage of the automatic transmission AT. The output shaft of the automatic transmission AT is connected to the left and right rear wheels RL and RR via a propeller shaft PS, a differential DF, a left drive shaft DSL, and a right drive shaft DSR.

  The hybrid drive system of the first embodiment includes an electric vehicle travel mode (hereinafter referred to as “EV mode”), a hybrid vehicle travel mode (hereinafter referred to as “HEV mode”), and a drive torque control travel mode (hereinafter referred to as “ It has a travel mode such as “WSC mode”.

  The “EV mode” is a mode in which the first clutch CL1 is disengaged and the vehicle travels only with the power of the motor generator MG.

  In the first embodiment, in the EV mode, EV traveling mode in which the motor generator MG is driven with the driving force of the motor generator MG with the torque of the motor generator MG being positive as the power running operation state, and the motor generator MG is decelerated with the torque of the motor generator MG being negative by regeneration. EV decelerating running mode can be formed.

  The “HEV mode” is a mode in which the first clutch CL1 is engaged and the vehicle travels with the driving force of the engine Eng and the motor generator MG. In the first embodiment, in the HEV mode, an engine travel mode, a motor assist travel mode, a travel power generation mode, and an HEV deceleration travel mode can be formed.

  The engine running mode is a mode in which the torque of the motor generator MG is set to 0 and the engine runs at a positive torque of the engine Eng.

  The motor assist travel mode is a mode in which the engine Eng torque and the motor generator MG torque are both positive.

  The traveling power generation mode is a mode of traveling while generating power by the motor generator MG as a regenerative operation state in which the torque of the engine Eng is positive while the torque of the motor generator MG is negative.

  In contrast to the travel power generation mode, the HEV decelerating travel mode is a power running operation state in which the torque of the motor generator MG is positive, while the torque of the engine Eng is a negative value having a larger absolute value than the torque of the motor generator MG due to friction. In this mode, the vehicle travels at a reduced speed.

  In the “WSC mode”, for example, when starting from the “EV mode” or starting from the “HEV mode”, the clutch transmission torque that causes the second clutch CL2 to be in the slip engagement state and the second clutch CL2 elapses is set. In this mode, the vehicle starts while controlling the clutch torque capacity so that the required driving torque is determined according to the vehicle state and the driver's operation. “WSC” is an abbreviation for “Wet Start clutch”.

  Next, the control system of the hybrid vehicle will be described.

  The control system of the FR hybrid vehicle in the first embodiment includes an engine controller 1, a motor controller 2, an inverter 3, a battery 4, a first clutch controller 5, a first clutch hydraulic unit 6, an AT controller 7, The second clutch hydraulic unit 8, the brake controller 9, the integrated controller 10, and the traction controller 30 are configured. The engine controller 1, the motor controller 2, the first clutch controller 5, the AT controller 7, the brake controller 9, the integrated controller 10, and the traction controller 30 are CAN communication lines 11 that can mutually exchange information. Connected through.

  The engine controller 1 inputs the engine speed information from the engine speed sensor 12, the target engine torque command from the integrated controller 10, and other necessary information. Then, a command for controlling the engine operating point (Ne, Te) is output to the throttle valve actuator of the engine Eng.

  The motor controller 2 inputs information from the resolver 13 that detects the rotor rotational position of the motor generator MG, a target MG torque command and a target MG rotational speed command from the integrated controller 10, and other necessary information. Then, a command for controlling the motor operating point (Nm, Tm) of motor generator MG is output to inverter 3. The motor controller 2 monitors the battery charge amount SOC indicating the charge capacity of the battery 4, and this battery charge amount SOC information is used for control information of the motor generator MG and via the CAN communication line 11. To the integrated controller 10.

  The first clutch controller 5 inputs sensor information from the first clutch stroke sensor 15 that detects the stroke position of the piston 14a of the hydraulic actuator 14, the target CL1 torque command from the integrated controller 10, and other necessary information. Then, a command for controlling the engagement / release of the first clutch CL1 is output to the first clutch hydraulic unit 6 in the AT hydraulic control valve unit CVU.

  The AT controller 7 inputs information from an accelerator opening sensor 16, a vehicle speed sensor 17, and other sensors 18 (transmission input rotation speed sensor, inhibitor switch, etc.). Then, when traveling with the D range selected, a control command for searching for the optimum gear position based on the position where the operating point determined by the accelerator opening Apo and the vehicle speed Vsp exists on the shift map and obtaining the searched gear position is issued. Output to the AT hydraulic control valve unit CVU to control the engagement and release of each frictional engagement element (not shown). The shift map is a map in which an upshift line and a downshift line are written according to the accelerator opening and the vehicle speed. In addition to the automatic shift control, the AT controller 7 sends a command for controlling the engagement / release of the second clutch CL2 to the second clutch in the AT hydraulic control valve unit CVU when the target CL2 torque command is input from the integrated controller 10. Second clutch control to be output to the hydraulic unit 8 is performed.

  The brake controller 9 inputs a wheel speed sensor 19 that detects the wheel speeds of the four wheels, sensor information from the brake stroke sensor 20, a regenerative cooperative control command from the integrated controller 10, and other necessary information. And, for example, at the time of brake depression, if the regenerative braking force is insufficient for the required braking force obtained from the brake stroke BS, the shortage is compensated by the mechanical braking force (hydraulic braking force or motor braking force) Perform regenerative cooperative brake control.

  The traction controller 30 monitors the slip of the left and right rear wheels RL and RR, which are drive wheels, based on the wheel speed Wsp and the vehicle speed (vehicle speed) Vsp, and if the left and right rear wheels RL and RR slip, the integrated controller 10 Request torque down.

  The integrated controller 10 manages the energy consumption of the entire vehicle and has a function for running the vehicle with the highest efficiency. From the motor rotation speed sensor 21 that detects the motor rotation speed Nm and other sensors and switches 22. Necessary information and information are input via the CAN communication line 11. Then, the integrated controller 10 selects an operation mode that can realize the driving force desired by the driver according to the accelerator opening Apo, the battery charge amount SOC, and the vehicle speed Vsp (proportional to the transmission output shaft rotation speed). Then, the target MG torque or target MG rotational speed command is output to the motor controller 2, the target engine torque command is output to the engine controller 1, the target CL1 torque command is output to the first clutch controller 5, and the AT controller 7 The target CL2 torque command is output to and a regenerative cooperative control command is output to the brake controller 9.

  FIG. 2 is a control block diagram illustrating arithmetic processing executed by the integrated controller 10 of the FR hybrid vehicle to which the control device of the first embodiment is applied. FIG. 3 is a diagram illustrating a target driving force map used when calculating the target driving force tFo0 in the integrated controller 10 of the FR hybrid vehicle to which the control device of the first embodiment is applied. FIG. 4 is a diagram showing an EV-HEV selection map used when mode selection processing is performed in the integrated controller 10 of the FR hybrid vehicle to which the control device of the first embodiment is applied. FIG. 5 is a diagram illustrating a target charge / discharge amount map used when battery charge control is performed by the integrated controller 10 of the FR hybrid vehicle to which the control device of the first embodiment is applied. Hereinafter, based on FIGS. 2-5, the arithmetic processing performed in the integrated controller 10 of Example 1 is demonstrated.

  As shown in FIG. 2, the integrated controller 10 includes a target driving force calculation unit 100, a mode selection unit 200, a target charge / discharge calculation unit 300, and an operating point command unit 400.

  The target driving force calculation unit 100 calculates a target driving force tFo0 from the accelerator opening Apo and the vehicle speed Vsp using the target driving force map shown in FIG.

  The mode selection unit 200 selects “EV mode” or “HEV mode” as the target travel mode from the accelerator opening Apo and the vehicle speed Vsp using the EV-HEV selection map shown in FIG. However, if the battery charge SOC is equal to or less than the predetermined value, the “HEV mode” is forcibly set as the target travel mode. Further, when starting from the “EV mode” or “HEV mode”, the “WSC mode” is selected as the target travel mode until the vehicle speed Vsp reaches the first set vehicle speed Vsp1.

  The target charge / discharge calculation unit 300 calculates the target charge / discharge power tP from the battery SOC using the target charge / discharge amount map shown in FIG.

  In the operating point command unit 400, the operating point reaching target is based on input information such as the accelerator opening Apo, the target driving force tFo0, the target travel mode, the vehicle speed Vsp, the target charging / discharging power tP, and the battery charge amount SOC. As described above, a transient target engine torque, a target MG torque, a target CL2 torque capacity, a target AT shift, and a CL1 solenoid current command are calculated. Then, the target engine torque command, the target MG torque command, the CL1 solenoid current command, the target CL2 torque capacity, and the target AT shift are output to the controllers 1, 2, 5, and 7 via the CAN communication line 11.

  2 constitutes a part of the AT controller 7, and the shift control unit 500 uses the automatic transmission to achieve this from the target CL2 torque capacity and the target AT shift. Drive control of solenoid valve in AT.

  FIG. 6 is a skeleton diagram showing an example of the automatic transmission AT.

  This automatic transmission AT includes three planetary gears 601, 602, 603, seven fastening elements F / B, I / C, D / C, H & LR / C, Rev / B, Fwd / B, each of which includes a clutch or a brake. LC / B, three one-way clutches 3rdOWC, 1stOWC, and FwdOWC are provided.

  In this automatic transmission AT, the gear stages in which the one-way clutch OWC is interposed are the first and second gear stages. In the automatic transmission AT, the first speed is formed by fastening the fastening element Fwd / B, and the second speed is formed by fastening the fastening elements Fwd / B and D / C.

  Therefore, for example, when the engine Eng and the motor generator MG accelerate by outputting a positive torque at the first gear, the respective engagement elements F / B, Fwd / B and the one-way clutch FwdOWC receive the torque. Torque is transmitted to the output shaft (propeller shaft PS). When the total torque of engine Eng and motor generator MG is negative and negative torque is input to input shaft IPS of automatic transmission AT, one-way clutch FwdOWC is disengaged, and torque is output to output shaft (propeller shaft PS). Will not be transmitted and the input rotation will decrease.

  This state is shown by the alignment chart of FIG. That is, FIG. 7A shows a state in which the gear stage of the automatic transmission AT is at the first speed and a positive torque is input to the input shaft IPS, and FIG. This shows a state in which a negative torque is being input to the input shaft IPS at high speed.

  That is, when negative torque is input to the input shaft IPS and the one-way clutch FwdOWC is disengaged, the sun gears S2 and S3 of the planetary gear 602 are in a free state. There is a possibility that the rotational speed is lowered and the rotational speed of the ring gear R1 is lowered. Since the ring gear R1 is connected to the input shaft IPS of the automatic transmission AT, the input shaft rotational speed IPSm also decreases. When the input shaft rotational speed IPSm decreases excessively, the engine Eng stalls. There is also a possibility that the engine Eng and the motor generator MG may rotate in reverse.

  Therefore, the integrated controller 10 executes torque distribution processing between the engine Eng and the motor generator MG when executing the drive wheel slip control to prevent the input shaft rotational speed IPSm from excessively decreasing. Hereinafter, the flow of processing of the drive wheel slip control will be described based on the flowchart of FIG.

  This drive wheel slip control is executed at a preset control cycle. In the first step S1, it is determined whether or not the wheel slip amount of the left and right rear wheels RL, RR that are drive wheels has exceeded a preset slip threshold value. When the threshold value is not exceeded, one flow is finished without executing the drive wheel slip control.

  In step S2, a torque down target value is determined, and the process proceeds to next step S3. Here, the torque down target value is set as the upper limit value of the input torque of the automatic transmission AT. At this time, the look-down target value may be determined as an input torque of the automatic transmission AT, an output torque of the automatic transmission AT, a propeller shaft torque, or a drive shaft torque. Good.

  In step S3, it is determined whether or not the current gear is a gear that receives torque by the one-way clutch OWC. Specifically, in the first embodiment, it is determined whether or not the first gear or the second gear. In the case of the first speed or the second speed, the process proceeds to step S4, and in the case of other gear stages, the process proceeds to step S5.

  In step S4, an input torque lower limit value (torque threshold value at torque down) of the automatic transmission AT at a gear stage that receives torque by the one-way clutch OWC is set. In this case, the input torque lower limit value is set to a value at which the input torque of the automatic transmission AT is not negative, and is set to “± 0” in the first embodiment.

  In step S5, it is determined whether or not the torque-down target value is smaller than a preset target value threshold value. If the target value threshold value is smaller than the target value threshold value, the process proceeds to step S6. Proceed to S7.

  In step S6, a power generation amount limiting process is performed, and the process proceeds to step S7. In this power generation amount limiting process, as the torque down target value decreases, the power generation torque is decreased so that the absolute value of the negative torque of the motor generator MG due to power generation decreases.

  In step S7, torque distribution of engine Eng and motor generator MG is determined. In determining the torque distribution, as shown in FIG. 10, the comparator 701 selects a larger value between the torque down target value and the input torque lower limit value of the automatic transmission AT, and the subtractor 702 compares the values. A value obtained by subtracting the target engine torque (the target engine torque is a torque obtained by adding the power generation amount in the motor generator MG) from the output of the controller 701 is set as a motor torque command value. The target engine torque is directly used as the engine torque command value.

  Here, the target engine torque is calculated by the operating point command unit 400. In the first embodiment, the target engine torque is determined by the torque cut by the fuel cut and the torque by the ignition timing adjustment according to the battery charge amount SOC. Either down is selected. That is, as shown in FIG. 9, when the battery charge amount SOC is equal to or less than the F / C non-permitted SOC threshold based on the F / C non-permitted SOC threshold having hysteresis and the F / C permissible SOC threshold, the fuel cut is performed. Torque down is prohibited, torque reduction is performed by adjusting the ignition timing, and a target engine torque corresponding to this is set. On the other hand, when the battery charge amount SOC is equal to or greater than the F / C permission SOC, the fuel cut is permitted, the torque is reduced by the fuel cut, and the target engine torque corresponding to this is set.

  That is, torque reduction by adjusting the ignition timing has a smaller torque reduction amount than torque reduction by fuel cut. As the torque reduction amount is reduced, the torque reduction amount (power generation amount) based on the motor torque command value is set larger based on the configuration shown in FIG.

  Next, an operation example will be described based on the time chart shown in FIG. In addition, this time chart has shown the operation example when a driver | operator performs sudden acceleration operation from the state which is generating electric power as HEV mode, and a driving wheel slip arises during a stop.

  In this example, while the vehicle is stopped from the time point t0 to the time point t1, the engine torque (positive) and the motor torque (negative) are balanced, and the motor generator MG generates power.

  At time t1, the driver performs an acceleration operation to depress an accelerator pedal (not shown). As a result, the engine torque increases rapidly, slipping occurs on the left and right rear wheels RL, RR, which are drive wheels, and the wheel speed is Transition to a state that greatly exceeds the speed (Vsp).

  At this time, when the wheel speed Wsp exceeds the vehicle speed (vehicle speed Vsp) by a predetermined value and the drive wheel slip exceeds the slip threshold, the process proceeds from step S1 to S2 in the drive wheel slip control flow shown in FIG. A torque down target value that suppresses the occurrence of drive wheel slip is determined. This torque down target value is determined by the traction controller 30, for example, and this torque down target value is set as the upper limit value of the transmission input torque. Accordingly, thereafter, the target driving force set for the driver's acceleration (torque) request will not exceed the torque-down target value.

  By setting the torque reduction target value, the engine torque is reduced immediately after time t2. Furthermore, the gear stage at the time of start from the stop state is controlled to the first speed. In the first speed, the transmission input torque lower limit value (= 0) is set based on the processing of steps S3 → S4 because the gear stage includes the one-way clutch OWC for torque transmission.

  Thereafter, in the example shown in this time chart, since the wheel slip amount is large, the torque-down target value becomes a negative value at time t3. Then, when the torque down target value becomes a negative value in this way, the torque reduction target value becomes smaller than the target value threshold value in step S5, and thus the power generation amount limiting process in step S6 is executed. By this power generation amount limiting process, the power generation torque, that is, the absolute value of the negative torque of the motor generator MG is limited so as to decrease as the torque down target value decreases. The method of limiting the power generation torque at this time may be set so that the power generation torque decreases as the slip amount increases, or the power generation torque decreases as the engine speed decreases. You may set so that a torque may become small.

  As a result of the above processing, the engine torque reduction is executed from the time point t2, and the lower limit of the transmission input torque set in step S4 while the torque reduction target value is a negative value after the time point t3. Based on the value, the engine torque is limited to 0 after time t4, and at the same time, the power generation torque of the motor generator MG is limited to 0 based on the power generation amount limitation in step S6.

  Thereafter, as the wheel speed Wsp decreases based on the torque down control, as the torque down target value increases from “negative” to “positive”, the engine torque rises at time t5, By starting the power generation by the motor generator MG to generate negative torque and controlling the distribution of engine torque and motor torque to an appropriate amount, the wheel speed Wsp further approaches the vehicle body speed (Vsp).

  When the drive wheel slip becomes smaller, the torque down target value changes from “negative” to “positive” (at time t6). Thereafter, at time t7 just before the wheel speed Wsp falls below the vehicle speed (Vsp), the torque is reduced. The total target torque obtained by adding the engine torque and the motor generator torque is controlled to a value that forms an acceleration state in which the wheel speed Wsp slightly exceeds the vehicle body speed (Vsp).

  As described above, the total input torque of the engine Eng and the motor generator MG does not become a negative value of “0” or less at the time point between t3 and t6 when the torque down target value becomes negative. Be controlled.

  Therefore, even if torque transmission is performed via the one-way clutch OWC, the one-way clutch OWC can be prevented from being released. As a result, the input shaft rotation speed IPSm of the automatic transmission AT can be prevented from extremely decreasing, and the engine stop and the reverse rotation of the engine Eng and the motor generator MG due to the decrease in the input shaft rotation speed IPSm can be prevented. it can.

As described above, in the apparatus of the first embodiment, the following effects can be obtained.
a) In a device that performs torque-down control by the traction controller 30 when drive wheel slip occurs, the torque is reduced when the automatic transmission AT is in a gear stage (first speed, second speed) in which the one-way clutch OWC is interposed for torque transmission. Regardless of the target value, the torque-down limiting process is performed so that the total input torque of engine Eng and motor generator MG does not become a negative value equal to or lower than the lower limit (0).

  Therefore, torque reduction is performed in the HEV mode, and the one-way clutch OWC is released, so that the input shaft rotational speed IPSm of the automatic transmission AT is not extremely reduced. Therefore, it is possible to prevent the engine from stopping due to the input shaft rotation speed IPSm of the automatic transmission AT being extremely lowered, and the reverse rotation of the engine Eng and the motor generator MG.

  b) The power generation amount limiting process for reducing the power generation amount of the motor generator MG is performed during the torque reduction limiting process in the HEV mode.

  Therefore, compared with the case where the power generation amount of the motor generator MG is not reduced, it becomes easier to control the input torque of the automatic transmission AT so as not to become negative, and the input shaft rotational speed is extremely high as in the above a). Therefore, it is possible to more reliably prevent the occurrence of problems such as engine stoppage due to a decrease in the speed.

  c) Since the decrease in the power generation amount of the motor generator MG in the above b) is set according to the torque down target value, the power generation amount, that is, the negative torque of the motor generator MG, is accurately matched to the torque reduction amount. Can be reduced.

  Further, the power generation amount decrease can be set not only according to the torque down target value, but also according to any or all of the slip amount of the drive wheel and the engine speed.

  As a result, the input shaft torque of the automatic transmission AT can be prevented from becoming negative due to variations in torque of the engine Eng, the motor generator MG, and the fastening elements.

  d) The power generation amount limiting process performed in step S6 is executed when the torque-down target value, which is the target value of the total input torque at the time of executing the torque-down process, is smaller than a preset target value threshold value. . For this reason, at the time of executing the torque-down process, normally, it is possible to achieve a large torque reduction by using the power generation amount of the motor generator MG without limiting the power generation amount, while the input shaft rotational speed IPSm is stopped. In a situation where the engine speed is likely to decrease, the amount of torque reduction can be accurately limited to prevent the engine from stopping and the engine Eng and the motor generator MG from rotating in reverse.

  e) In reducing the engine torque, the engine torque is reduced by fuel cut or by adjusting the ignition timing based on the F / C permission SOC threshold and the F / C non-permission SOC threshold according to the battery charge amount SOC. I switched it.

  For this reason, when the battery charge amount SOC is high, it is easy to obtain torque reduction effect by performing torque reduction by fuel cut. In addition, motor generator MG not only performs regeneration (power generation), but also performs power running and is free to prevent the torque reduction amount from becoming excessive.

  Further, when the battery charge amount SOC decreases, the fuel cut of the engine Eng is prohibited, the motor generator MG can easily generate power, and the battery charge amount can be increased.

  f) The integrated controller 10 performs a process of giving a target engine torque command value to the engine Eng for the torque distribution between the engine Eng and the motor generator MG in the torque down restriction process, while the torque down target value is transmitted to the motor generator MG. A process of giving a command value obtained by subtracting the target engine torque command value from the larger value of the transmission input torque lower limit value is performed.

  For this reason, the total input torque can be prevented from falling below the transmission input torque lower limit value.

  As mentioned above, although the control apparatus of the hybrid vehicle of this invention was demonstrated based on Example 1, it is not restricted to this Example 1 about a concrete structure, The invention which concerns on each claim of a claim Design changes and additions are permitted without departing from the gist of the present invention.

  In the first embodiment, the configuration including the engine Eng, the first clutch CL1, the motor generator MG, and the second clutch CL2 (built in the automatic transmission AT) is shown as the configuration of the hybrid vehicle. However, the configuration is not limited to the configuration illustrated in FIG. 1. For example, a configuration in which the second clutch CL <b> 2 is not used may be employed. Further, the first clutch CL1 may be omitted and the vehicle may travel only in the HEV mode.

  In the first embodiment, the target value threshold value and the transmission input torque lower limit value are both set to “0”. However, there is a possibility that the input rotational speed of the transmission may stop the engine. The value is not limited to “0” as long as it can prevent a decrease to the rotational speed, and may be set to a positive value or a negative value.

  In the first embodiment, an FR hybrid vehicle using the left and right rear wheels RL and RR as drive wheels is shown as the hybrid vehicle, but an FF hybrid vehicle using the left and right front wheels as drive wheels and a 4WD hybrid vehicle using four wheels as drive wheels. Can also be applied.

3rdOWC One-way clutch 1stOWC One-way clutch FwdOWC One-way clutch 10 Integrated controller (torque-down limiting means)
30 Traction controller (torque control means)
AT automatic transmission Eng Engine IPS Input shaft IPSm Input shaft speed MG Motor generator (motor)
RL Left rear wheel (drive wheel)
RR Right rear wheel

Claims (7)

A control device for a hybrid vehicle in which an engine and a motor are connected to an input shaft side of a transmission having a gear stage in which a one-way clutch is interposed,
Torque control means for executing torque down processing for reducing drive wheel slip by reducing input torque of the transmission when the slip detection means detects drive wheel slip; and
The total input torque of the engine and the motor to the input shaft is set in advance when the gear stage of the transmission is a gear stage with the one-way clutch interposed during execution of the torque down process. A control device for a hybrid vehicle, comprising: a torque-down limiting unit that distributes torque between the engine and the motor so that the torque threshold is not smaller than a torque threshold value. As the motor, a motor generator capable of forming a power running state driven by power supply and a regenerative state receiving power generated by rotation energy is used,
The hybrid vehicle control device according to claim 1, wherein the torque-down limiting process of the torque-down limiting unit includes a power generation amount limiting process for limiting a power generation amount of the motor generator.   The power generation amount limiting process is executed when a torque-down target value, which is a target value of the total input torque at the time of executing the torque-down process, is smaller than a preset target value threshold value. Item 2. The hybrid control device according to Item 1.   The torque control means performs the power generation amount based on at least one of an input torque of the transmission, a driving wheel slip amount, and an engine speed in the power generation amount limiting process. The control apparatus of the hybrid vehicle of Claim 2 or Claim 3.   The said torque control means includes the process which sets the preset lower limit to the said total input torque in the said torque down restriction | limiting process, The any one of Claims 1-4 characterized by the above-mentioned. Hybrid vehicle control device.   The torque control means performs a process of giving a target engine torque command value to the engine for torque distribution between the engine and the motor in the torque-down limiting process, while the torque-down target value and the lower limit are applied to the motor. 5. The control apparatus for a hybrid vehicle according to claim 4, further comprising a process of giving a command value obtained by subtracting the target engine torque command value from a larger value.   The torque control means permits the torque reduction by the fuel supply cut to the engine when the battery charge amount is larger than a preset charge amount threshold according to the battery charge amount in the torque down restriction process. In addition, when the charging amount is smaller than the threshold value, it includes a process of prohibiting torque reduction by cutting fuel supply to the engine and performing torque reduction by adjusting ignition timing. The hybrid vehicle control device according to claim 6.

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