JP5309962B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device for a hybrid vehicle including a drive system in which a clutch is set between an engine and a motor.

In the conventional vehicle clutch learning device, when the controller (ECU) first learns a torque point for transmitting a predetermined torque when the clutch is connected from the disengaged state, the clutch input side rotational speed and the engine speed The clutch is gradually engaged while detecting the number, and when the input side rotational speed of the clutch falls more than a predetermined rotational speed with respect to the engine rotational speed in the process, the duty ratio value at that time is once taken into the ECU, After correction, learning was performed as a torque point learning value (see, for example, Patent Document 1).
JP 2002-286056 A

  However, when the conventional clutch learning device for a vehicle is used as an engine start clutch in a hybrid vehicle, it learns after waiting for a drop in the rotational speed, and then performs engine start control. There was a problem of this.

  The present invention has been made by paying attention to the above-described problem, and it is possible to prevent a delay in engine start due to learning correction and to realize a stable engine start by correcting variation in clutch torque. An object is to provide a control device.

In order to achieve the above object, a control device for a hybrid vehicle of the present invention comprises a clutch interposed between an engine and a motor,
A clutch actuator for engaging / disengaging the clutch;
Clutch control means for engaging / disengaging the clutch based on a stroke-torque map indicating a relationship between an actuator stroke and a clutch transmission torque, and
When shifting from the electric vehicle travel mode in which the clutch is released to the hybrid vehicle travel mode in which the clutch is engaged, the motor is used as an engine start motor, and the engine is started by motor torque transmitted through the clutch.
In this hybrid vehicle control device, the clutch control means includes a clutch impulse applied to the engine by the clutch within a range of impulse evaluation time during engine start control, and impulse evaluation time during engine start control. The engine impulse received from the clutch within the range of the engine is compared, and if there is a relationship of clutch impulse <engine impulse , the clutch engagement / release control in the direction of increasing the actual clutch torque. If the relationship of clutch impulse> engine impulse is found, the stroke-torque map used for clutch engagement / release control is learned in the direction of decreasing the actual clutch torque. to correct.

Therefore, in the hybrid vehicle control device of the present invention, the clutch control means gives the clutch impulse applied to the engine by the clutch control means and the engine The engine impulse received from the engine is compared, and if there is a relationship of clutch impulse <engine impulse , the stroke-torque map used for clutch engagement / release control is learned and corrected in the direction of increasing the actual clutch torque. When there is a relationship of clutch impulse> engine impulse, the stroke-torque map used for clutch engagement / release control is learned and corrected in the direction of decreasing the actual clutch torque . Note that “impulse” refers to the product of a force and the time during which the force is applied.
That is, since learning correction can be performed in a series of engine start control flows, delays in engine start due to learning correction are prevented. If the stroke-torque map is appropriate, the relationship between the clutch impulse and the engine impulse is clutch impulse = engine impulse. However, for example, when there is a relationship of clutch impulse <engine impulse, since the actual clutch torque is too small, the stroke-torque map is learned and corrected in the direction of increasing the actual clutch torque. In this way, by performing learning correction based on the impulse comparison result, the clutch impulse and engine impulse coincide with each other with respect to the clutch torque temperature variation, etc., and there is no motor pull-in or engine start delay. Engine start is realized.
As a result, it is possible to prevent a delay in engine start associated with the learning correction, and to realize a stable engine start by correcting the clutch torque variation.

  Hereinafter, the best mode for realizing a control device for a hybrid vehicle of the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration 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 (clutch), a motor generator MG (motor), and 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, and a right rear wheel RR. 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. In addition, the first clutch control hydraulic pressure controls the engagement / release including the half-engaged 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 alternating current generated by an inverter 3 is applied based on a control command from the motor controller 2. It is controlled by doing. The motor generator MG can operate as an electric motor that is driven to rotate by receiving electric power from the battery 4 (hereinafter, this operation 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 (hereinafter, this operation state is referred to as “regeneration”). Note that the rotor of the motor generator MG is connected to the 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 and RR. The second clutch CL2 is operated by the second clutch hydraulic unit 8 based on a second clutch control command from the AT controller 7. The generated and controlled hydraulic pressure controls the fastening and opening including slip fastening and slip opening. 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 built 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 speed 1 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 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 has two modes, an electric vehicle travel mode (hereinafter referred to as “EV mode”) and a hybrid vehicle travel mode (hereinafter referred to as “HEV mode”), depending on the engaged / released state of the first clutch CL1. Has two driving modes. The “EV mode” is a mode in which the first clutch CL1 is released and the vehicle runs only with the power of the motor generator MG. The “HEV mode” is a mode in which the first clutch CL1 is engaged and the vehicle is driven by the power of the engine Eng and the motor generator MG. In addition, when shifting from the “EV mode” in which the first clutch CL1 is released to the “HEV mode” in which the first clutch CL1 is engaged, the motor generator MG is used as an engine starting motor, and the first clutch CL1 is in a semi-engaged state. The engine start control for starting the engine Eng is performed by the motor torque transmitted in this manner.

Next, the control system of the hybrid vehicle will be described.
As shown in FIG. 1, 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, and a first clutch hydraulic unit 6. And an AT controller 7, a second clutch hydraulic unit 8, a brake controller 9, and an integrated controller 10. 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 or the like of the engine Eng.

  The motor controller 2 inputs information from the resolver 13 that detects the rotor rotation position of the motor generator MG, the target MG torque command and target MG rotation 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 SOC that indicates the state of charge of the battery 4, and this battery SOC information is used for control information of the motor generator MG and is integrated via the CAN communication line 11. Supplied to.

  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 engagement / disengagement 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 / switches 18. Then, when driving with the D range selected, a control command for obtaining the searched gear position is searched 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. Output to AT hydraulic control valve unit CVU. 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 above automatic shift control, when a target CL2 torque command is input from the integrated controller 10, a command for controlling engagement / release of the second clutch CL2 is output to the second clutch hydraulic unit 8 in the AT hydraulic control valve unit CVU. The second clutch control 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 with respect to the required braking force required from the brake stroke BS, the shortage is compensated with mechanical braking force (hydraulic braking force or motor braking force) Regenerative cooperative brake control is performed.

  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 integrated controller 10 detects the motor rotational speed Nm, and the second clutch output rotational speed. Information from the second clutch output rotational speed sensor 22 and the like for detecting N2out and information via the CAN communication line 11 are input. The target engine torque command is sent to the engine controller 1, the target MG torque command and the target MG speed command are sent to the motor controller 2, the target CL1 torque command is sent to the first clutch controller 5, the target CL2 torque command and the target gear speed command are sent to the AT controller 7. The 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 showing an EV-HEV selection map used when mode selection processing is performed by the integrated controller 10 of the FR hybrid vehicle. Hereinafter, based on FIG.2 and FIG.3, 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 APO and the vehicle speed VSP using the target driving force map.

  The mode selection unit 200 uses the EV-HEV selection map shown in FIG. 3 to select “EV mode” or “HEV mode” as the target travel mode from the accelerator opening APO and the vehicle speed VSP. However, if the battery SOC is equal to or lower than the predetermined value, the “HEV mode” is forcibly set as the target travel mode.

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

  In the operating point command unit 400, based on input information such as the accelerator opening APO, the target driving force tFoO, the target travel mode, the vehicle speed VSP, the target charge / discharge power tP, etc., the target engine torque is set as the operating point reaching target. , Target MG torque, target MG rotation speed, target CL1 torque, target CL2 torque, and target gear position are calculated. Then, the target engine torque command, the target MG torque command, the target MG rotational speed command, the target CL1 torque command, the target CL2 torque command, and the target shift speed command are sent to each of the controllers 1, 2, 5, 7 via the CAN communication line 11. Output to.

  FIG. 4 shows the clutch outline and the piston stroke for mode management of the first clutch CL1 of the FR hybrid vehicle to which the control device of the first embodiment is applied in each state of the full release mode, the half clutch mode, and the full engagement mode. It is a figure which shows a hydraulic-torque characteristic.

  First, as shown in FIG. 4, the first clutch CL1 includes a flywheel 40, a pressure plate 41, a clutch disk 42, clutch facings 43 and 44, a clutch cover 45, a diaphragm spring 46, and a spring support portion. 47, a release plate 48, and a hydraulic actuator 14 having a piston 14a.

  The first clutch CL1 in the fully open mode state (= “EV mode” state) is released from the action of the spring force from the diaphragm spring 46 on the pressure plate 41 as shown in the left part of FIG. It becomes. And, the hydraulic pressure / torque characteristics with respect to the piston stroke for mode management are such that the piston stroke is at the maximum position, the hydraulic pressure is maximum at this time, and the torque (clutch capacity) is zero.

  In the first clutch CL1 in the half clutch mode state (= the engine starting state from the “EV mode”), a part of the spring force from the diaphragm spring 46 against the pressure plate 41 is released as shown in the center portion of FIG. Thus, the clutch is semi-engaged. The hydraulic pressure / torque characteristics with respect to the piston stroke for mode management are such that the piston stroke is at an intermediate position. At this time, the hydraulic pressure is lower than the maximum hydraulic pressure, and the torque (clutch capacity) is at a level that keeps the clutch slipping.

  In the first clutch CL1 in the fully engaged mode state (= “HEV mode” state), the spring force from the diaphragm spring 46 acts on the pressure plate 41 as shown in the right part of FIG. It becomes. And, the hydraulic pressure / torque characteristics with respect to the piston stroke for mode management are such that the piston stroke is at the minimum position, and at this time, the hydraulic pressure is minimum and the torque (clutch capacity) is maximum.

  FIG. 5 is a control block diagram illustrating arithmetic processing executed by the first clutch controller 5 to which the control device of the first embodiment is applied.

As shown in FIG. 5 , the first clutch controller 5 (clutch control means) includes a learning permission determination block 51, a correction factor calculation block 52, a CL1 stroke-torque map learning correction block 53, and a stroke difference calculation block 54. And a control command calculation block 55.

  The learning permission determination block 51 includes mode information (extracting an engine start scene by switching a travel mode from “EV mode” to “HEV mode”), engine speed information, target MG speed information, and actual MG speed. Information, MG torque value information, gear position information, and CL2 differential rotation information are input. Then, based on these pieces of information, it is determined whether a plurality of learning permission determination conditions are satisfied after the engine start command is issued. When a plurality of learning permission determination conditions are satisfied, a learning permission flag is set.

  The correction factor calculation block 52 inputs the learning permission flag from the learning permission determination block 51, the engine speed information, and the first clutch stroke information from the first clutch stroke sensor 15. The clutch impulse Sc applied to the engine Eng by the first clutch CL1 within the range of the impulse evaluation time during engine start control and the engine Eng within the range of the impulse evaluation time during engine start control A correction factor (= Se / Sc), which is a ratio of the engine impulse Se received from one clutch CL1, is calculated, and this correction factor is output as a learning value.

The CL1 stroke-torque map learning correction block 53 sets a CL1 stroke-torque map that characterizes the relationship between the first clutch torque and the first clutch stroke, and the correction factor information acquired by the correction factor calculation block 52. Is taken as a learning value and reflected in the CL1 stroke-torque map.
On the other hand, when the target CL1 torque command is input from the integrated controller 10 to the CL1 stroke-torque map learning correction block 53, the CL1 stroke-torque map set at that time is searched to obtain the target CL1 torque command. The corresponding target CL1 stroke is determined.

  The stroke difference calculation block 54 inputs the target CL1 stroke from the CL1 stroke-torque map learning correction block 53 and the actual CL1 stroke from the first clutch stroke sensor 15, and calculates the stroke difference between the target CL1 stroke and the actual CL1 stroke. Calculate.

  The control command calculation block 55 receives the stroke difference from the stroke difference calculation block 54 and calculates a control command for matching the actual CL1 stroke with the target CL1 stroke. Then, the control command obtained by this calculation is output to the first clutch hydraulic unit 6.

  FIG. 6 is a flowchart showing the flow of the learning correction control process executed by the learning permission determination block 51, the correction factor calculation block 52, and the CL1 stroke-torque map learning correction block 53 of the first clutch controller 5 of the first embodiment. is there. Hereinafter, each step will be described.

In step S101, based on the travel mode switching determination from the “EV mode” to the “HEV mode”, whether or not the four learning permission determination conditions are all satisfied after the engine start command is issued, that is, the learning permission determination is made. If yes (learning permission is determined), a learning permission flag is set and the process proceeds to step S102. If No (no learning permission is determined), the determination in step S101 is repeated.
Here, the four learning permission determination conditions are an MG rotation speed stabilization condition, an MG torque stabilization condition, a low-side gear position condition, and a CL2 transmission torque stabilization condition.

In step S102, following the determination that the learning permission determination has been made in step S101, it is determined whether or not an impulse calculation condition permitting impulse calculation is satisfied. If Yes (impact calculation condition satisfied) Advances to step S103, and in the case of No (impact calculation condition is not satisfied), the determination in step S102 is repeated.
Here, the impulse calculation condition is satisfied when the engine condition and the first clutch condition are both satisfied. As engine conditions, an engine coolant temperature condition that the engine coolant temperature is 60 ° C. or higher and other conditions (decompression amount, crank angle, etc.) are used. As the first clutch condition, a clutch torque condition in which the first clutch torque is 150 Nm or more (target torque when starting the engine) is used.

  In step S103, following the determination that the impulse calculation condition is satisfied in step S102, it is determined whether or not the impulse calculation range lower limit, that is, the impulse calculation start condition, that is, whether the engine speed has reached 200 rpm or more, Yes If the impulse calculation start condition is satisfied, the process proceeds to step S104. If No (impulse calculation start condition is not satisfied), the process returns to step S102.

  In step S104, following the determination that the impulse calculation start condition is satisfied in step S103 or the determination that the impulse calculation end condition is not satisfied in step S106, the impulse calculation end condition is satisfied from the time when the impulse calculation start condition is satisfied. The first clutch torque map value (CL1 torque calculation) is calculated using the stroke detection value from the first clutch stroke sensor 15 and the stroke-torque map at that time within the range of the impulse evaluation time up to the time point. Information) is acquired, stored in the memory, and the process proceeds to step S105.

  In step S105, following the acquisition and storage of the CL1 torque calculation information in step S104, within the range of the impulse evaluation time from when the impulse calculation start condition is satisfied to when the impulse calculation end condition is satisfied, for each calculation cycle. The engine speed information from the engine speed sensor 12 is acquired and stored by overwriting when the engine speed is higher than the previous value, and the process proceeds to step S106.

In step S106, following the acquisition and storage of the engine speed information in step S105, the impulse calculation range upper limit, which is the impulse calculation end condition, that is, crank rotation of two (720 degrees) after the engine speed reaches 200 rpm or more. It is determined whether reached, in the case of Yes (impulse calculation end condition is satisfied), the process proceeds to step S107, in the case of No (impulse operation end condition is not satisfied) returns to step S104.

In step S107, following the determination that the impulse calculation end condition is satisfied in step S106, the difference between the first clutch torque map value T_CL1 acquired in step S105 and the engine friction T_EF is calculated from the start time of the impulse evaluation to the end time. The clutch impulse Sc applied by the first clutch CL1 to the engine Eng is estimated by performing the integration calculation until the process proceeds to step S108.
Here, the calculation formula of the clutch impulse Sc is
Sc = ∫ (T_CL1-T_EF) dt
It is.

In step S108, following the estimation of the clutch impulse Sc in step S107, the engine Eng is calculated based on the product of the engine reached revolution speed Ne_goal and the engine inertia (IP_eng + IP_cl) reached with the rise in the revolution speed at the end time of the impulse evaluation. The engine impulse Se received from the first clutch CL1 is calculated, and the process proceeds to Step S109.
Here, the calculation formula of the engine impulse Se is:
Se = Ne_goal × (IP_eng + IP_cl)
It is.

  In step S109, following the calculation of the engine impulse Se in step S108, a correction factor (= Se / Sc) that is a ratio of the clutch impulse Sc and the engine impulse Se is calculated, and the process proceeds to step S110.

In step S110, following the calculation of the correction factor in step S109, the acquired correction factor is used as the clutch learning value and reflected in the CL1 stroke-torque map, and the CL1 stroke-torque map characteristic is learned and corrected, and the process proceeds to the end.
Here, the learning correction of the CL1 stroke-torque map characteristic is performed by integrating the correction rate over the entire torque axis of the stroke-torque map, that is, by multiplying the vertical axis of the map proportionally by the correction rate.

Next, the operation will be described.
The actions in the control apparatus for the FR hybrid vehicle of the first embodiment are changed to “basic learning correction concept”, “stroke-torque map learning correction control action”, and “CL1 stroke-torque map characteristic correction factor reflecting action”. Separately described.

[Basic learning correction concept]
FIG. 7 shows the characteristics of the stroke, the first clutch torque, and the engine speed for explaining the basic learning correction concept during the engine start control in the engine start scene that switches from the “EV mode” to the “HEV mode”. It is a time chart which shows. Hereinafter, the basic concept of learning correction will be described with reference to FIG.

  First, in the engine start scene where the “EV mode” is switched to the “HEV mode”, the engine start is started from the “EV mode” where the engine Eng is stopped and the first clutch CL1 is released, and then the first clutch CL1 is engaged to the intermediate capacity. Control begins. Therefore, during the engine start control in which the first clutch CL1 is changed from the disengaged state to the half-engaged state of the intermediate capacity, the learning correction of the CL1 stroke-torque map used for the engagement / disengagement control of the first clutch CL1 is performed. Suitable scene.

  The basic learning correction concept of the present invention is that the engine impulse is received from the first clutch CL1 and the clutch impulse Sc applied by the first clutch CL1 to the engine Eng with respect to the CL1 stroke-torque map during engine start control. The ratio of the engine impulse Se is calculated as a correction factor, and the CL1 stroke-torque map is corrected by the correction factor.

  That is, assuming that the clutch stroke in the “EV mode” in which the first clutch CL1 is released is the standby stroke, when the engine start control is started, as shown in the stroke characteristic at the top of FIG. Reduce the stroke amount and maintain the stroke when the target stroke is reached. By this stroke operation, the first clutch CL1 is changed from the released state (standby stroke) to the half-engaged state (target stroke) of the intermediate capacity.

  In this stroke operation, as shown in the first clutch torque characteristic in the center of FIG. 7, a fixed time A is determined from the start of the stroke until the target stroke is maintained, but before the engine Eng first detonates. The time obtained by excluding the waste stroke time B at which the first clutch torque is not generated from A is the impulse evaluation time.

  Therefore, the clutch impulse Sc applied to the engine Eng by the first clutch CL1 is obtained by subtracting the engine friction from the first clutch torque characteristic (first clutch torque characteristic indicated by the phantom line in FIG. 7) (according to the solid line in FIG. 7). The first clutch torque characteristic) is estimated by performing integral calculation from the start time to the end time of impulse evaluation. That is, the clutch impulse Sc represents an area surrounded by the clutch torque characteristic during the impulse evaluation time.

  On the other hand, the engine impulse Se received by the engine Eng from the first clutch CL1 is, as shown in the engine rotation speed characteristic at the lower part of FIG. And the product of the inertia of the engine Eng.

  Of the clutch impulse Sc and engine impulse Se thus obtained, the engine impulse Se is a value actually received by the engine Eng from the first clutch CL1. On the other hand, the clutch impulse Sc is a value obtained by clutch control using the CL1 stroke-torque map.

  Therefore, if the CL1 stroke-torque map is appropriate, the relationship between the clutch impulse Sc and the engine impulse Se becomes the clutch impulse Sc = the engine impulse Se. However, for example, when there is a relationship of clutch impulse Sc <engine impulse Se, the actual clutch torque is too small. Therefore, it is necessary to perform learning correction on the CL1 stroke-torque map in the direction of increasing the actual clutch torque. Further, for example, when there is a relationship of clutch impulse Sc> engine impulse Se, the actual clutch torque is excessive, and therefore it is necessary to perform learning correction on the CL1 stroke-torque map in the direction of decreasing the actual clutch torque.

  From the above relationship, when the correction factor (= Se / Sc), which is one of the impulse comparison indicators, is calculated, the acquired correction factor is used as the clutch learning value and reflected in the CL1 stroke-torque map. If the map characteristic is learned and corrected, it is possible to correct the clutch impulse Sc and the engine impulse Se so as to maintain the coincidence between the clutch torque temperature variation and individual variation.

[Stroke-torque map learning correction control action]
FIG. 8 is a time chart showing characteristics of the first clutch torque and the engine speed during the engine start control in the engine start scene where the “EV mode” is switched to the “HEV mode”. Hereinafter, the learning correction control operation of the CL1 stroke-torque map will be described with reference to FIGS.

  When the learning permission determination is made, the impulse calculation condition is satisfied, and the impulse calculation start condition is satisfied, step S101 → step S102 → step S103 → step S104 → step S105 → step in the flowchart of FIG. Proceed to S106. While the impulse calculation end condition is not satisfied, the flow of going from step S104 to step S105 to step S106 is repeated. That is, in step S104, the first clutch torque map value is determined using the stroke detection value from the first clutch stroke sensor 15 and the CL1 stroke-torque map at that time for each calculation cycle within the range of the impulse evaluation time. Is obtained and this data is stored in the memory. In the next step S105, the engine speed information from the engine speed sensor 12 is acquired every calculation cycle within the range of the impulse evaluation time, and is overwritten when the engine speed is higher than the previous value. Is stored.

  When the impulse calculation end condition in step S106 is satisfied, the process advances from step S106 to step S107 → step S108 → step S109. That is, in step S107, the first clutch CL1 is engine-engaged by integrating the difference between the first clutch torque map value T_CL1 acquired in step S105 and the engine friction T_EF from the start time to the end time of the impulse evaluation. The clutch impulse Sc given to is estimated. In the next step S108, the engine impulse Se received by the engine Eng from the first clutch CL1 based on the product of the engine reaching revolution speed Ne_goal and the engine inertia (IP_eng + IP_cl) reached at the end time of the impulse evaluation with an increase in the revolution speed. Is calculated. In the next step S109, a correction factor (= Se / Sc) that is a ratio of the clutch impulse Sc and the engine impulse Se is calculated.

  In step S110, following the calculation of the correction factor in step S109, the acquired correction factor is used as a clutch learning value, and this is reflected in the CL1 stroke-torque map for learning correction.

As described above, in the first embodiment, the variation in the clutch torque during the engine start control is equal to the engine revolution speed at a certain time × the engine inertia (= the engine impulse Se received by the engine Eng) up to the same time ( The clutch torque capacity is calculated by comparing the time integral value of the clutch engagement torque capacity-engine friction) (= the clutch impulse Sc given by the first clutch CL1) and correcting the CL1 stroke-torque map of the first clutch CL1. I am trying to correct.
Therefore, temperature variations and individual variations of the first clutch torque are corrected, and stable engine start (no motor pull-in and engine start delay) is realized.

In the first embodiment, the “engine impulse Se”, which is a time integral value of the torque received by the engine Eng, is evaluated by the engine rotation speed × engine inertia.
That is, although it is possible to estimate the actual torque from the increase in engine rotation, this increase in engine rotation is highly variable and unstable.
Therefore, when evaluated by the engine revolution speed x engine inertia, the influence of variation due to the increase in engine rotation is reduced, and the correction accuracy is improved.

In the first embodiment, the learning condition based on the impulse calculation range is defined (60 ° C. or higher) by the engine coolant temperature at that time.
That is, the engine friction varies greatly depending on the temperature (engine cooling water temperature). Therefore, since the learning condition is defined by the engine coolant temperature at that time, it is possible to avoid learning correction that causes excessive torque capacity when the engine coolant temperature is low.

In the first embodiment, the engine speed is not evaluated at a certain speed (for example, 200 rpm) or less.
That is, the static friction torque at the initial rotation of the engine varies greatly depending on the crank angle and the compression state at that time.
Therefore, by not evaluating in the low engine speed range, the influence of variations in static friction torque at the initial stage of engine rotation is reduced, and learning correction accuracy is improved.

In the first embodiment, the impulse evaluation time from the start of evaluation is set until the engine Eng reaches two revolutions.
That is, when the engine rotation reaches two rotations, the engine Eng is started, and the engine rotation speed changes due to the engine initial explosion torque. In other words, it is different from the engine speed reached by purely the clutch torque.
Therefore, by defining the impulse evaluation time until the engine Eng reaches two revolutions, the learning correction accuracy is improved without being affected by the engine initial explosion torque.

[CL1 stroke-correction rate reflection effect on torque map characteristics]
FIG. 9 is a map characteristic diagram showing a CL1 stroke-torque map before correction and a CL1 stroke-torque map after correction used for the engagement / release control of the first clutch in the FR hybrid vehicle of the first embodiment. Hereinafter, based on FIG. 9, the correction factor reflecting effect on the CL1 stroke-torque map characteristics will be described.

  In step S110 of FIG. 6, the acquired correction factor is used as a clutch learning value, and the CL1 stroke-torque map characteristic is learned and corrected. This learning correction adds the correction factor to the entire torque axis of the stroke-torque map. This is done by multiplying the vertical axis (torque axis) of the map proportionally by the correction factor.

  For example, in the case where the actual torque is larger than the map, when the corrected map is shifted and corrected with respect to the original map to increase the torque, the initial target torque is 150 Nm as shown in FIG. It moves in the direction of increasing stroke from the target stroke position at the time to the target stroke position when the corrected target torque is 150 Nm. In other words, the stroke is on the cut side (open side) due to excessive actual torque.

  Since the entire CL1 stroke-torque map is corrected according to the actual torque, even if the target torque changes after correction, the correction amount is reflected and the corrected target stroke can be obtained. That is, as shown in FIG. 9, even if the target torque changes from 150 Nm to 200 Nm, the corrected target stroke can be obtained by using the corrected map.

As described above, in the first embodiment, the correction rate (= correction gain) obtained by impulse comparison is integrated over the entire Y axis (torque axis) of the CL1 stroke-torque map.
Therefore, even if the target torque or the target stroke changes, the correction gain reflecting the correction factor is effective, and it is not necessary to perform learning correction again for each target torque or target stroke, so that versatility can be provided.

Next, the effect will be described.
In the control device for the FR hybrid vehicle of the first embodiment, the effects listed below can be obtained.

  (1) A clutch (first clutch CL1) interposed between the engine Eng and the motor (motor generator MG), a clutch actuator (hydraulic actuator 14) for engaging / disengaging the clutch, and an actuator stroke And a clutch control means (first clutch controller 5) for performing engagement / disengagement control based on a stroke-torque map indicating the relationship between the clutch transmission torque and the clutch (first clutch CL1). ("EV mode"), when shifting to the hybrid vehicle running mode ("HEV mode") in which the clutch (first clutch CL1) is engaged, the motor is used as an engine starter motor and is transmitted via the clutch. Hybrid vehicle that starts the engine Eng by motor torque (F In the control device for the R hybrid vehicle, the clutch control means (the first clutch controller 5) is configured such that the clutch impulse Sc applied to the engine Eng by the clutch within a range of impulse evaluation time during engine start control. The engine Eng compares the engine impulse Se received from the clutch within the range of the impulse evaluation time during engine start control, and is used for clutch engagement / release control based on the impulse comparison result. Learning correction of the stroke-torque map to be performed. For this reason, it is possible to prevent a delay in engine start associated with the learning correction and to realize a stable engine start by correcting the variation in clutch torque.

  (2) The clutch control means (first clutch controller 5) uses the stroke detection value and the stroke-torque map at that time for each calculation cycle within the range of impulse evaluation time during engine start control. 1 clutch torque map value is acquired, and the clutch impulse Sc is estimated by integrating the difference between the first clutch torque map value and engine friction from the start time to the end time of impulse evaluation. For this reason, the clutch impulse Sc can be accurately estimated by considering the influence of engine friction during the impulse evaluation time.

  (3) The clutch control means (first clutch controller 5) acquires engine rotational speed information within a range of impulse evaluation time during engine start control, and accompanies an increase in rotational speed at the end time of impulse evaluation. The engine impulse Se is calculated from the product of the reached engine speed and the engine inertia. For this reason, the influence of variation due to the rotation increase of the engine Eng is reduced, and the learning correction accuracy of the stroke-torque map can be improved.

  (4) The clutch control means (first clutch controller 5) uses an impulse calculation condition for permitting impulse calculation that the cooling water temperature of the engine Eng is equal to or higher than a set temperature. For this reason, the influence of fluctuations in engine friction when the cooling water temperature of the engine Eng is low is reduced, and learning correction with excessive torque capacity can be avoided.

  (5) The clutch control means (the first clutch controller 5) sets the lower limit of the calculation range when the engine speed of the engine Eng becomes equal to or higher than a low speed range threshold (for example, 200 rpm) during engine start control. Start product evaluation time. For this reason, the influence of variation in the static friction torque of the engine Eng is reduced, and the learning correction accuracy of the stroke-torque map can be improved.

  (6) During the engine start control, the clutch control means (first clutch controller 5) detects when the engine speed reaches the crank rotation speed (for example, 2 rotations) before starting the initial explosion from the start of the impulse evaluation time. Set the upper limit of the calculation range and end the impulse evaluation time. Therefore, the engine Eng is not affected by the first explosion, and the stroke-torque map learning correction accuracy can be improved.

  (7) The clutch control means (first clutch controller 5) obtains a correction factor (= Se / Sc) which is a ratio of the clutch impulse Sc and the engine impulse Se, and uses this correction factor as the stroke-torque. By integrating the entire torque axis of the map, the correction factor is reflected to correct the learning of the characteristics of the stroke-torque map. For this reason, even if the target torque or the target stroke changes, the correction gain reflecting the correction factor is effective, and it is not necessary to re-learn and correct each target torque or target stroke, thereby providing versatility.

  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, as an evaluation time of the engine impulse Se, an example in which a time from when the engine speed reaches 200 rpm to when the engine Eng rotates twice is shown. However, during engine start control, if it is within the time to start the engine, the evaluation time of the engine impulse Se received by the engine Eng is the time from the start of clutch engagement until reaching a certain number of revolutions, or from the start of clutch engagement. It can also be evaluated by the engine speed reached up to a certain time.

  In the first embodiment, the control device according to the present invention is applied to the first clutch of the FR hybrid vehicle. However, the FF hybrid vehicle and the parallel type / combined type motor provided with a power split mechanism instead of the automatic transmission are shown. The present invention can also be applied to control devices for various types of hybrid vehicles such as a cyst type. In short, any control device for a hybrid vehicle including a drive system having an electric vehicle traveling mode in which a clutch is interposed between an engine and a motor and the clutch is released and a hybrid vehicle traveling mode in which the clutch is engaged can be applied.

1 is an overall system diagram showing an FR hybrid vehicle (an example of a hybrid vehicle) by rear wheel drive to which a 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 in the integrated controller 10 of FR hybrid vehicle. Outline of the clutch in the full release mode, half-clutch mode, and full engagement mode of the first clutch CL1 of the FR hybrid vehicle to which the control device of the first embodiment is applied, and the hydraulic pressure / torque characteristics with respect to the piston stroke for mode management FIG. It is a control block diagram which shows the arithmetic processing performed in the 1st clutch controller 5 to which the control apparatus of Example 1 was applied. 6 is a flowchart showing the flow of a learning correction control process executed by a learning permission determination block 51, a correction factor calculation block 52, and a CL1 stroke-torque map learning correction block 53 of the first clutch controller 5 of the first embodiment. A time chart showing the characteristics of stroke, first clutch torque, and engine speed for explaining the basic learning correction concept during engine start control in the engine start scene that switches from “EV mode” to “HEV mode” is there. 6 is a time chart showing characteristics of a first clutch torque and an engine speed during engine start control in an engine start scene that is switched from “EV mode” to “HEV mode”. FIG. 6 is a map characteristic diagram showing a CL1 stroke-torque map before correction and a CL1 stroke-torque map after correction used for engagement / release control of the first clutch in the FR hybrid vehicle of the first embodiment.

Explanation of symbols

Eng engine
FW flywheel
CL1 1st clutch (clutch)
MG motor generator (motor)
CL2 2nd clutch
AT automatic transmission
PS propeller shaft
DF differential
DSL left drive shaft
DSR right drive shaft
RL left rear wheel
RR right rear wheel
FL Left front wheel
FR Right front wheel 5 1st clutch controller (clutch control means)
51 Learning permission determination block 52 Correction rate calculation block 53 CL1 stroke-torque map learning correction block 14 Hydraulic actuator 14a Piston 15 First clutch stroke sensor Sc Clutch impulse Se Engine impulse

Claims (7)

A clutch interposed between the engine and the motor,
A clutch actuator for engaging / disengaging the clutch;
Clutch control means for engaging / disengaging the clutch based on a stroke-torque map indicating a relationship between an actuator stroke and a clutch transmission torque, and
A hybrid that uses the motor as an engine starter motor and starts the engine by motor torque transmitted through the clutch when shifting from the electric vehicle drive mode in which the clutch is released to the hybrid vehicle drive mode in which the clutch is engaged. In a vehicle control device,
The clutch control means is configured so that the clutch applied to the engine by the clutch within the range of the impulse evaluation time during engine start control and the engine within the range of the impulse evaluation time during engine start control. The engine impulse received from the clutch is compared, and if there is a relationship of clutch impulse <engine impulse, a stroke-torque map used for clutch engagement / release control is increased in the direction of increasing the actual clutch torque. When the learning is corrected, and there is a relationship of clutch impulse> engine impulse , the hybrid is characterized by learning and correcting a stroke-torque map used for clutch engagement / disengagement control in the direction of decreasing the actual clutch torque. Vehicle control device. In the hybrid vehicle control device according to claim 1,
The clutch control means acquires a first clutch torque map value using a stroke detection value and a stroke-torque map at that time for each calculation cycle within a range of impulse evaluation time during engine start control, A hybrid vehicle control apparatus characterized in that the clutch impulse is estimated by integrating the difference between one clutch torque map value and engine friction from the start time to the end time of impulse evaluation. In the hybrid vehicle control device according to claim 1 or 2,
The clutch control means acquires engine rotation speed information within the range of the impulse evaluation time during engine start control, and the engine arrival rotation speed and engine inertia reached with an increase in rotation speed at the end time of the impulse evaluation. The hybrid vehicle control apparatus, wherein the engine impulse is calculated by a product. In the control apparatus of the hybrid vehicle described in any one of Claim 1- Claim 3,
The hybrid vehicle control apparatus, wherein the clutch control means uses an impulse calculation condition for permitting impulse calculation that the engine coolant temperature is equal to or higher than a set temperature. In the hybrid vehicle control device according to any one of claims 1 to 4,
The clutch control means starts the impulse evaluation time by setting the lower limit of the calculation range when the engine speed of the engine is equal to or higher than a low speed range threshold during engine start control. . In the hybrid vehicle control device according to claim 5,
The clutch control means sets the upper limit of the calculation range when starting the impulse evaluation time during the engine start control and before reaching the first explosion of the engine, and ends the impulse evaluation time. A control device for a hybrid vehicle. In the hybrid vehicle control device according to any one of claims 1 to 6,
The clutch control means obtains a correction factor that is a ratio of the clutch impulse and the engine impulse, and integrates the correction factor over the entire torque axis of the stroke-torque map to reflect the correction factor. A hybrid vehicle control device that learns and corrects characteristics of a stroke-torque map.

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