JP2010143512A - Control apparatus for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control apparatus for a hybrid vehicle which can suppress variations in torque, at low cost, when switching from EV mode to HEV mode, by suppressing the discrepancy between the target engine torque and the actual engine torque by obtaining the target engine torque during travelling in HEV mode from the actual motor torque of a motor, when travelling in the EV mode. <P>SOLUTION: The integrated control apparatus 10 is for the hybrid vehicle which carries out calculation processes for the target engine torque that corrects the target engine torque during HEV travelling, based on the difference between the actual engine torque and the target engine torque by obtaining the actual motor torque in EV, at a point when the vehicle speed is converged to the target vehicle speed during traveling in the EV mode with automatic cruising control and obtaining the actual engine torque from the actual motor torque in HEV, when traveling in the HEV mode, thereafter. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control apparatus for a hybrid vehicle including an engine and a motor as drive sources, and more particularly to an apparatus for executing auto-cruise control for converging a vehicle speed to a target vehicle speed.

Conventionally, in a hybrid vehicle including an engine and a motor, what performs so-called auto-cruise control for maintaining the vehicle speed at a target vehicle speed is described in, for example, Patent Document 1.
In this conventional technology, during auto-cruise control, the vehicle travels in a first mode in which only the motor is driven (this mode is hereinafter referred to as the EV mode), and a second mode in which the motor and the engine are driven (this mode is Hereinafter, the torque control is performed using a different control map.
JP 2001-191814 A

However, in a conventional hybrid vehicle control device, there may be a difference between the actual engine torque actually output from the engine and the target engine torque commanded from the control device to the engine.
In this case, during the execution of the auto-cruise control, the traveling mode is changed from the first mode in which only the motor is driven (this mode is hereinafter referred to as the EV mode) to the second mode in which the motor and the engine are driven ( When this mode is switched to the HEV mode), a torque fluctuation based on the difference between the target engine torque and the engine actual torque occurs, and a shock due to the torque fluctuation occurs in the vehicle.

  The present invention has been made paying attention to the above problem, and by obtaining the target engine torque during HEV mode travel from the actual motor torque of the motor during EV mode travel, the difference between the target engine torque and the engine actual torque is obtained. An object of the present invention is to provide a control device for a hybrid vehicle that can reduce the torque fluctuation at the time of switching from the EV mode to the HEV mode at low cost.

  In order to achieve the above object, in the hybrid vehicle control device of the present invention, the control means is configured to control the motor at the time when the vehicle speed has converged to the target vehicle speed during the first mode driving in which the motor is driven only during motor cruise control. First-mode motor actual torque, which is torque, is obtained, and target engine torque calculation processing is performed for obtaining the target engine torque based on the first-mode motor actual torque during the second mode running in which the motor and the engine are driven. A control device for a hybrid vehicle is provided.

In the control device for a hybrid vehicle of the present invention, the control means performs the first mode motor actuality when the vehicle speed converges to the target vehicle speed when traveling in the first mode (EV mode) during auto-cruise control. Find the torque. And a control means calculates | requires a target engine torque based on the motor actual torque at the time of 1st mode in a target engine torque calculation process at the time of the 2nd mode driving | running which drives an engine and a motor.
Here, the motor actual torque in the first mode is an actual torque necessary for causing the vehicle to travel at the target vehicle speed. Therefore, the target engine torque required for converging the vehicle speed to the target vehicle speed during the second mode traveling is obtained based on the first mode motor actual torque, so that the target engine torque is obtained as the first mode motor actual torque. It is possible to suppress the deviation between the target engine torque and the actual engine torque, as compared with the setting regardless of whether or not.
Therefore, it is possible to suppress the occurrence of torque fluctuation at the time of transition from the first mode to the second mode, and it is possible to suppress the occurrence of a shock due to this torque fluctuation in the vehicle.
In addition, since this torque correction is performed based on the actual torque of the motor, the above-described shock suppression can be achieved at a lower cost compared with a case where correction is performed by separately providing a sensor for detecting engine torque.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the hybrid vehicle control device according to the embodiment of the present invention, a first clutch (CL1) is interposed between an engine (Eng) and a motor / generator (MG), and the motor / generator (MG) is driven wheels. A control device for a hybrid vehicle connected to the vehicle, the vehicle state detecting means including a vehicle speed detecting means (17) for detecting the vehicle speed, and the auto cruise commanding the auto cruise running to run at a constant vehicle speed The operation of the command means (23), the engine (Eng), the motor / generator (MG), and the first clutch (CL1) is controlled, and the travel mode is set to release the first clutch (CL1). A first mode in which only the motor / generator (MG) is driven and the engine (Emg) is engaged by engaging the first clutch (CL1). And the second mode in which the motor / generator (MG) is driven to drive, and at the time of command by the auto-cruise command means (23), the auto-cruise control is performed to converge the vehicle speed to the target vehicle speed. Control means (10) for controlling the motor / generator (MG) at the time when the vehicle speed converges to the target vehicle speed during the first mode traveling during the auto-cruise control. A hybrid that performs a target engine torque calculation process for obtaining a motor actual torque in the first mode, which is a torque, and obtaining a target engine torque based on the motor actual torque in the first mode during the second mode traveling. A control device for a vehicle.

Based on FIGS. 1-8, the hybrid vehicle control apparatus of Example 1 of the best mode for carrying out the invention will be described.
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 engine start control, engine stop control, and throttle valve opening control are performed 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 generated by the first clutch hydraulic unit 6 based on a first clutch control command from the first clutch controller 5. Engagement / release is controlled by the first clutch control hydraulic pressure including the half clutch state. 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.

  The 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 a three-phase AC generated by an inverter 3 based on a control command from the motor controller 2. It is controlled by applying. 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 rotates from the engine Eng or the driving wheel. When receiving energy, the battery 4 can be charged by functioning as a generator that generates electromotive force at both ends of the stator coil (this operation state is hereinafter referred to as “regeneration”). The rotor of the motor / generator MG is connected to the transmission input shaft of the 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. Based on a second clutch control command from the AT controller 7, the second clutch hydraulic unit 8 The fastening / release including slip fastening and slip releasing is controlled by the control hydraulic pressure generated by the above. 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, for example, a stepped transmission that automatically switches stepped speeds such as forward 7 speed / reverse 1 speed according to vehicle speed, accelerator opening, etc., and the second clutch CL2 However, it is not newly added as a dedicated clutch, but the most suitable clutch or brake arranged in the torque transmission path is selected from among a plurality of friction 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, the motor / generator MG torque is positive by power running and the motor / generator MG is driven by the driving force, and the motor / generator MG torque is negative by regeneration to decelerate. EV traveling mode in which the vehicle travels 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 travel mode is a mode in which the torque of the motor / generator MG is 0 and the vehicle travels with the 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. Is a mode in which 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, and the integrated controller 10 are included. The engine controller 1, the motor controller 2, the first clutch controller 5, the AT controller 7, the brake controller 9, and the integrated controller 10 are connected via a CAN communication line 11 that can mutually exchange information. ing.

  The engine controller 1 inputs engine speed information from the engine speed sensor 12, a 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 representing 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 is connected to 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, a 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 driving point determined by the accelerator pedal opening AP 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 for detecting 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 integrated controller 10 manages the energy consumption of the entire vehicle and has a function for running the vehicle with the highest efficiency. The motor rotation number sensor 21 for detecting the motor rotation number Nm and other sensors and switches 22 Necessary information and information via the CAN communication line 11 are input. Then, the target engine torque command to the engine controller 1, the target MG torque command and the target MG rotational speed command to the motor controller 2, the target CL1 torque command to the first clutch controller 5, the target CL2 torque command to the AT controller 7, and the brake controller 9 Regenerative cooperative control command is output.

Furthermore, the integrated controller 10 performs auto-cruise control. The auto-cruise control is a control for keeping the vehicle at the target vehicle speed by converging the vehicle speed to a set target vehicle speed. At this time, the driving torque of the motor / generator MG and the driving torque of the engine Eng are controlled.
The integrated controller 10 is connected to an auto-cruise operation switch 23 that commands execution of the auto-cruise control and a gradient sensor 24 that detects the gradient of the traveling road surface based on the gravitational acceleration.

  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 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. 4 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. 2-4, 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 tFoO from the accelerator opening AP and the vehicle speed VSP using the target driving force map.

  The mode selection unit 200 selects “EV mode” or “HEV mode” as the target travel mode from the accelerator opening AP and the vehicle speed VSP using the EV-HEV selection map shown in FIG. 3. 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.

  Next, target engine torque calculation processing during HEV mode traveling, which is a feature of the first embodiment, executed by the integrated controller 10 of the first embodiment will be described.

In this target engine torque calculation process, an engine torque correction process for obtaining an engine torque correction coefficient in the EV mode, and a process for calculating a target engine torque based on the engine torque correction coefficient obtained in the engine torque correction process include: Executed.
FIG. 5 shows the flow of engine torque correction processing, and FIG. 6 shows the flow of target engine torque calculation processing.

  FIG. 5 shows the flow of processing during EV mode traveling. The actual motor torque in the EV mode, which is the actual motor torque during EV mode traveling, is obtained, and the motor is switched to the HEV mode forcibly. The HEV motor actual torque that is the actual torque is obtained, and a process for obtaining the torque correction coefficient based on these is performed.

  That is, in step S1, it is determined whether or not the travel mode is the EV mode. If the travel mode is the EV mode, the process proceeds to the next step S2, and if the travel mode is a mode other than the EV mode, the process returns to the start. The EV mode is determined to be the EV mode when both the first clutch CL1 and the second clutch CL2 are engaged.

  In step S2, it is determined whether or not auto-cruise control is being executed (ASCD = ON). When auto-cruise control is executed, the process proceeds to the next step S3, and when it is not executed, the process returns to the start.

  In step S3, based on the auto cruise control, it is determined whether or not the vehicle speed has converged to the target vehicle speed Vmsp of the auto cruise control. If so, the process proceeds to the next step S4. If not, the process proceeds to step S2. Return to.

In the next step S4, the torque of the motor / generator MG at that time, that is, at the time when the vehicle speed converges to the target vehicle speed (motor actual torque in the first mode, hereinafter referred to as EV MG actual torque), vehicle speed. VSP and gradient θ data are acquired.
In the next step S5, based on the gradient θ, the EV MG actual torque is corrected to a value in the 0% gradient state.

Based on the processing of steps S1 to S5 described above, an EV MG actual torque value, which is the torque of the motor / generator MG during auto-cruise traveling in the EV mode, is acquired, and this EV MG actual torque is set to a 0% gradient. The process which correct | amends to the equivalent value of is performed.
In the next step S6, the traveling mode is forcibly shifted to the HEV mode. That is, the first clutch CL1 is engaged and the engine Eng is started.

  In the next step S7, it is determined whether or not the vehicle speed VSP has converged to the target vehicle speed Vmsp for auto-cruise control. If the vehicle speed VSP has converged, the process proceeds to the next step S8, and if it has not converged, the process returns to step S6.

  In step S8, the convergence target engine torque MTS, the engine speed Em, the vehicle speed VSP, the MG torque, and the gradient θ are acquired in a state where the vehicle speed VSP is the target vehicle speed Vmsp by auto-cruise control. Note that the MG torque at this time is negative when power generation is performed in a regenerative operation, and is a positive value when assist is performed in a power running operation. This is called MG actual torque at HEV.

  Further, in the next step S9, the convergence target engine torque MTS and the HEV MG actual torque in HEV traveling are corrected to values of the 0% gradient state.

  In the processes of steps S6 to S9 described above, the HEV mode MG actual torque and the convergence target engine torque MTS, which are the torques of the motor / generator MG executing the auto-cruising control in the HEV mode and performing the power running operation or the regenerative operation, Further, the HEV MG actual torque and the target engine torque MT are corrected to a value of 0% gradient.

In the next step S10, the engine actual torque TT is calculated.
This engine actual torque TT is obtained by subtracting the HEV MG actual torque corrected to the 0% gradient obtained in step S8 from the EV MG actual torque corrected to the 0% gradient obtained in step S5. When the regenerative operation is performed in the HEV mode, the HEV torque is a negative value, and therefore the absolute value of the HEV MG torque is added to the EV MG actual torque.

  In the next step S11, the convergence target engine torque MTSh obtained by correcting the engine torque correction coefficient Et to be equivalent to the 0% gradient is divided by the actual engine torque TT.

  In the next step S12, the obtained engine torque correction coefficient Et is stored and stored as a correction coefficient map in a predetermined storage area defined by the target engine torque MT and the engine speed Em.

Next, the flow of processing for outputting an engine command value when the travel mode is the HEV mode will be described.
First, in step S21, it is determined whether or not the travel mode is the HEV mode. If the travel mode is the HEV mode, the process proceeds to step S22. If the travel mode is not the HEV mode, the process returns to the start.

  In step S22, it is determined whether or not auto-cruise control is being executed. If auto-cruise control is being executed, the process proceeds to the next step S23, and when auto-cruise control is not being executed, the process returns to the start.

In step S23, a correction map corresponding to the current target engine torque MT and engine speed Em is read from the stored correction map.
In subsequent step S24, correction is performed by multiplying the current target engine torque MT by the engine torque correction coefficient Et.
In step S25, a process of outputting the corrected target engine torque MT is performed.

Next, the operation of the first embodiment will be described.
In the hybrid vehicle, when auto-cruise control is executed, EV mode travel and HEV mode travel are repeated.
That is, if the battery charge amount SOC is sufficient, the vehicle travels in the EV mode. If the battery charge amount SOC is insufficient or the MG torque is insufficient with respect to the target torque, the vehicle travels in the HEV mode. Therefore, when the vehicle continues to travel with auto cruise control, the EV mode and the HEV mode are repeated.

  Therefore, the operations during EV mode traveling and HEV mode traveling during auto-cruise control will be briefly described.

(During EV mode travel)
When the vehicle speed VSP converges to the target vehicle speed Vmsp during EV mode traveling, the target engine torque MT, engine speed Em, EV MG actual torque, vehicle speed VSP, and gradient θ at that time are acquired.
The EV MG actual torque at this time is an actual torque necessary to drive the vehicle at the target vehicle speed Vmsp. Further, the EV actual MG torque is corrected to an MG torque with a 0% gradient (based on the processing of steps S1, S2, S3, S4, and S5).

When the correction of the EV MG actual torque is completed, the travel mode is forcibly shifted to the HEV mode (step S6), and the HEV motor torque acquisition process for acquiring the motor torque in the HEV mode is started.
Thereafter, when the vehicle speed VSP converges to the target vehicle speed Vmsp in the HEV mode, the convergence target engine torque MTS, engine speed Em, HEV MG actual torque, vehicle speed VSP, and gradient θ at that time are acquired (step S8). .
Further, the obtained convergence target engine torque MTS is corrected to the convergence target engine torque MTSh at the 0% gradient based on the gradient θ (step S9).

Further, an actual engine torque TT is calculated (S10). That is, when the vehicle speed VSP converges to the same target vehicle speed Vmsp in the EV mode and the HEV mode, it can be considered that the same actual driving torque is applied to the vehicle.
Therefore, it can be considered that the EV MG actual torque during the EV mode traveling is equal to the torque obtained by adding the HEV MG actual torque to the engine torque during the HEV mode traveling. Therefore, if the HEV MG actual torque is subtracted from the EV MG actual torque, the engine actual torque TT in the HEV mode can be obtained.

  Further, the ratio between the corrected target engine torque MTSh after correction and the actual engine torque TT is obtained, and this is set as the engine torque correction coefficient Et (step S11). Therefore, the target engine torque MT and the actual engine torque TT can be matched by multiplying the target engine torque MT by the engine torque correction coefficient Et.

(When driving in HEV mode)
When executing the auto-cruise control in the HEV mode, the engine torque correction coefficient Et is read from the correction coefficient map corresponding to the target engine torque MT and the engine speed (step S23), and the engine torque correction coefficient is added to the target engine torque MT. Multiply Et (step S24) and output the target engine torque MT (step S25).

Next, an execution example of the target engine torque calculation process of the first embodiment will be described based on the time charts shown in FIGS.
FIG. 7 shows an example in which the engine torque correction coefficient Et is calculated by performing EV mode running and forced HEV mode running.
During traveling in the EV mode, auto-cruise control is started at time t1. Then, based on the auto cruise control, the vehicle speed VSP is converged to the target vehicle speed Vmsp. At the time t2 when the vehicle speed VSP converges to the target vehicle speed Vmsp, the EV MG actual torque, the vehicle speed VSP, and the gradient θ are acquired, and the EV MG actual torque is corrected to a value with a 0% gradient.

  In the example shown in the time chart, the slope is a positive value, and the EV MG actual torque MGTh corrected to the 0% slope indicated by the dotted line is lower than the EV MG actual torque indicated by the solid line. It has become.

Thereafter, the mode is forcibly shifted to the HEV mode at time t3. At this time, in the example shown in the time chart, the engine actual torque TT is larger than the target engine torque MT.
Therefore, an upward step is generated in the vehicle speed VSP from the time t3 until the vehicle speed VSP converges to the target vehicle speed Vmsp, and a shock is generated in the vehicle.

Thereafter, when the vehicle speed VSP converges to the target vehicle speed Vmsp (t4), the convergence target engine torque MTS, engine speed Em, HEV MG actual torque, vehicle speed VSP, and gradient θ at this time are acquired.
Then, the convergence target engine torque MTS and the HEV MG actual torque are corrected to 0% gradient values based on the gradient data. In the example shown in the time chart, the gradient is a positive value at time t4, and the target engine torque MT at the 0% gradient is a value indicated by a dotted line in the figure.

Further, the engine actual torque TT is calculated by subtracting the corrected HEV MG actual torque from the EV MG actual torque. At time t4, the motor / generator MG performs power generation by the regenerative operation, and the HEV-time MG actual torque is a negative value. Therefore, the engine actual torque TT at this time point t4 is a value obtained by adding the absolute value of the HEV MG actual torque to the EV MG actual torque.
In the example shown in the time chart of FIG. 7, the actual engine torque TT is shifted to a larger side than the target engine torque MT. In this case, the engine torque correction coefficient Et is a value smaller than 1.

After the engine torque correction coefficient Et is obtained in this manner, the target engine torque MT is corrected by multiplying the target engine torque MT by the engine torque correction coefficient Et during the HEV mode traveling.
That is, the time chart of FIG. 8 shows the vehicle speed VSP, the target engine torque MT, and the like when the correction is performed by multiplying the engine torque correction coefficient Et when the auto-cruise control is executed during the HEV mode traveling. Shows changes. As shown in this time chart, when the correction is not performed, the engine actual torque TT is shifted to the larger side with respect to the target engine torque MT, and a step is generated in the target engine torque MT and the vehicle speed VSP. In this case, a shock due to torque fluctuation occurs in the vehicle.

  In contrast, the corrected target engine torque MTK becomes smaller than the target engine torque MT without correction, the engine actual torque TT becomes appropriate, and the generation of steps in the target engine torque MT and the vehicle speed VSP is suppressed. Thus, it was possible to suppress the occurrence of shock due to torque fluctuation in the vehicle.

As described above, in the first embodiment, the effects listed below can be obtained.
a) EV actual MG torque when the vehicle speed VSP converges to the target vehicle speed Vmsp in EV mode traveling and HEV MG actual torque when the vehicle speed VSP converges to the same target vehicle speed Vmsp during HEV mode travel are obtained. The actual engine torque TT was calculated from the difference between the actual MG actual torque and the HEV actual MG torque.
Then, the engine torque correction coefficient Et was calculated from the target engine torque MT ratio during HEV mode traveling with respect to the engine actual torque TT.
Therefore, by performing correction by multiplying the target engine torque MT by the engine torque correction coefficient Et, an engine actual torque TT that matches the target engine torque MT and has no deviation can be obtained. From the EV mode to the HEV mode. The shock due to torque fluctuation at the time of transition to or at the start of auto-cruise control can be improved.
In addition, since this torque correction is performed based on the actual torque of the motor / generator MG, the above-described shock suppression can be achieved at a lower cost compared to a case where a sensor or the like for detecting engine torque is separately provided for correction. .

b) The EV MG actual torque, the HEV MG actual torque, and the target engine torque MT are corrected to values corresponding to a 0% gradient based on the gradient θ when the respective values are obtained. .
For this reason, an error due to a difference in gradient θ between EV traveling at which EV MG actual torque is obtained and HEV traveling at HEV MG actual torque and target engine torque MT is suppressed, and this gradient correction is not performed. Compared to the above, the deviation between the actual engine torque TT and the target engine torque MT can be further reduced. Therefore, a more appropriate engine torque correction coefficient Et can be obtained.

c) When the vehicle speed VSP converges to the target vehicle speed Vmsp and the EV actual motor torque is obtained during EV mode traveling, the vehicle is immediately forcibly shifted to the HEV mode to obtain the HEV MG actual torque and the target engine torque MT. I did it.
Therefore, the traveling condition for obtaining the EV MG actual torque and the traveling condition for obtaining the HEV MG actual torque and the target engine torque MT can be made as equal as possible, and an occurrence of an error due to a difference in the traveling conditions can be suppressed. Therefore, the deviation between the actual engine torque TT and the target engine torque MT is reduced to obtain a more appropriate engine torque correction coefficient Et as compared with the case where the EV mode MG actual torque is acquired and not immediately shifted to the HEV mode. be able to.

(Other examples)
Other embodiments will be described below. Since these other embodiments are modifications of the first embodiment, only the differences will be described, and the configuration common to the first embodiment or the other embodiments will be described. The description is omitted by giving a common reference numeral.

The second embodiment is different from the first embodiment in part of the engine torque correction process and the target engine torque calculation process.
That is, in the engine torque correction process shown in FIG. 9, in step S11b following step S10, the engine torque correction value H is calculated by subtracting the actual engine torque from the corrected target engine torque MTSh after convergence, and the next step S12b Thus, the engine torque correction value H is stored.

  Further, in the target engine torque calculation process shown in FIG. 10, the engine torque correction value H corresponding to the target engine torque MT and the engine speed Em is read in step S23b following step S22. In the next step S24b, the engine torque correction value H is added to the target engine torque MT to correct the target engine torque MT.

The operation of the second embodiment will be described based on an operation example shown in the time chart of FIG.
As shown in FIG. 11, there is a torque step between time t3b at which the EV mode is forcibly shifted to HEV mode and time t4b at which the vehicle speed VSP converges to the target vehicle speed Vmsp. This is because the actual engine torque TT is output larger than the target engine torque MT as shown in the figure.

  In such a case, in the second embodiment, the engine torque correction value H is a negative value.

  Therefore, as in the operation example shown in the time chart of FIG. 12, when traveling in the HEV mode, a negative engine torque correction value H is added to the target engine torque MT, and the corrected target engine torque MTH is obtained. Is a value lower than the target engine torque MT without correction. As a result, when the auto-cruise control is started, the occurrence of a torque step is suppressed and the vehicle shock is suppressed as compared with the case where the target engine torque MT without correction is used.

  As described above, the control device for a hybrid vehicle of the present invention has been described based on the embodiment and Examples 1 and 2, but the specific configuration is not limited to these Embodiment and Examples 1 and 2. Modifications and additions of the design are permitted without departing from the spirit of the invention according to each claim of the claims.

  In the first and second embodiments, the configuration of the FR hybrid vehicle includes the engine Eng, the first clutch CL1, the motor / generator MG, and the second clutch CL2 (built in the automatic transmission AT). 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. Moreover, although the motor / generator MG capable of power running and regeneration (power generation) is shown as a motor, a motor that performs only power running may be used.

  In the first and second embodiments, when the target engine torque is obtained from the EV MG actual torque as the first-mode motor actual torque, the engine actual torque TT is obtained from the difference from the HEV MG actual torque. From the engine actual torque TT and the convergence target engine torque MTS, the correction coefficient Et or the correction value H is obtained to obtain the target engine torque MT. However, if the target engine torque MT is obtained from the EV-time MG actual torque, the method is not limited to the method shown in the embodiment. That is, since the necessary drive torque can be obtained accurately and inexpensively from the EV MG actual torque, it is sufficient that the target engine torque can be obtained from the necessary drive torque.

  In the first embodiment, the application example to the FR hybrid vehicle in which the first clutch is interposed between the engine and the motor / generator is shown. However, the first clutch is omitted and the engine and the motor / generator are directly connected. It can also be applied to FR hybrid vehicles and FF hybrid vehicles.

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 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. 3 is a flowchart illustrating a flow of an engine torque correction process executed by the integrated controller 10 according to the first embodiment. 3 is a flowchart illustrating a flow of target engine torque calculation processing executed by the integrated controller 10 according to the first embodiment. 6 is a time chart illustrating an example of an operation when an engine torque correction process is executed by the control device according to the first embodiment. 6 is a time chart illustrating an example of an operation when a target engine torque calculation process is executed by the control device according to the first embodiment. 6 is a flowchart showing a flow of engine torque correction processing executed by an integrated controller 10 in Embodiment 2. 6 is a flowchart showing a flow of target engine torque calculation processing executed by an integrated controller 10 in Embodiment 2. It is a time chart which shows an example of operation at the time of performing engine torque amendment processing by the control device of Example 2. 6 is a time chart illustrating an example of an operation when a target engine torque calculation process is executed by the control device of the second embodiment.

Explanation of symbols

10 Integrated controller (control means)
17 Vehicle speed sensor (vehicle speed detection means)
23 Auto cruise operation switch (Auto cruise command means)
24 Gradient sensor (gradient detection means)
CL1 First clutch Eng Engine H Engine torque correction value MG Motor / generator (motor)
MGTh EV corrected MG actual torque MT Target engine torque MTS Converged target engine torque MTSh Converged target engine torque MTH after 0% gradient correction Target engine torque MTK corrected by correction value After correction by correction coefficient Target engine torque RL Left rear wheel (drive wheel)
RR Right rear wheel (drive wheel)
TT Engine actual torque Vmsp Target vehicle speed VSP Vehicle speed θ Gradient

Claims (5)

A control device for a hybrid vehicle in which a first clutch is interposed between an engine and a motor, and the motor is connected to a drive wheel side,
Traveling state detecting means for detecting a traveling state including vehicle speed detecting means for detecting the vehicle speed;
Auto-cruise command means for commanding auto-cruise running at a constant vehicle speed;
The operation of the engine, the motor, and the first clutch is controlled, the travel mode is set, the first mode in which the first clutch is released and only the motor is driven, and the first clutch is engaged. Control means for executing auto-cruise control for converging the vehicle speed to a target vehicle speed at the time of command by the auto-cruise command means, while being controllable to a second mode in which the engine and the motor are driven to travel.
With
In the auto cruise control, the control means obtains a first mode motor actual torque that is a torque of the motor when the vehicle speed converges to a target vehicle speed during the first mode travel, and during the second mode travel. And a target engine torque calculation process for obtaining a target engine torque based on the motor actual torque in the first mode.   In the target engine torque calculation process, the control means includes a first mode motor actual torque and a second torque that are torques of the motor when the vehicle speed converges to the target vehicle speed in the first mode and the second mode, respectively. 2. The control apparatus for a hybrid vehicle according to claim 1, wherein the target engine torque is obtained based on a difference from an actual motor torque in mode.   In the target engine torque calculation process, the control means calculates the engine actual torque in the second mode based on the difference between the motor actual torque in the first mode and the motor actual torque in the second mode, The hybrid vehicle according to claim 2, wherein the target engine torque is obtained based on the engine actual torque and a convergence target engine torque that is a target engine torque when the engine actual torque is obtained. Control device. The traveling state detection means includes a slope detection means for detecting a road surface slope,
The motor torque in the first mode and the motor torque in the second mode are corrected to a value corresponding to the gradient based on the gradient detected by the gradient detecting means. Hybrid vehicle control device.   In the target engine torque calculation process at the time of the auto-cruise control, the control means forcibly when the vehicle speed converges to the target vehicle speed in the first mode and the motor torque in the first mode is obtained. 5. The second mode motor torque acquisition process for performing the second mode travel and acquiring the second mode motor torque is performed. 6. Hybrid vehicle control device.

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