JP2019143754A - Control device of vehicle - Google Patents

Abstract

To provide a control device of a vehicle capable of properly suppressing generation of engagement shock and judder, when an object to be controlled, is a vehicle provided with an automatic transmission in which power is transmitted by engagement of a plurality of engagement elements.SOLUTION: In a control device of a vehicle including an automatic transmission having an input shaft, an output shaft, a first clutch and a second clutch, a neutral state for blocking power transmission between the input shaft and the output shaft is set by releasing both of the first clutch and the second clutch, and a prescribed shift stage is set by engagement of both of the first clutch and the second clutch to have a power transmission state between an engine and a driving wheel, an input shaft torque Te of the automatic transmission and a transmission torque capacity Tc1 of the first clutch are respectively controlled to engage the first clutch so that an output shaft torque of the automatic transmission becomes a fixed value in a case when the automatic transmission is changed from the neutral state to the power transmission state.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a control device that controls a vehicle equipped with an automatic transmission, and in particular, engages an engagement element from a neutral state in which the engagement element of the automatic transmission is released and power transmission is interrupted to thereby determine a predetermined value. The present invention relates to a vehicle control device that controls the output of an engine and the operation of an engagement element when shifting to a state in which the gear position is set.

  Patent Document 1 discloses a vehicle shift control device that is intended to control a vehicle equipped with an automatic transmission and that reduces shift shock during clutch-to-clutch shift. The shift control device for a vehicle described in Patent Document 1 is a shift control for changing a shift stage by proceeding in parallel with release and engagement of a clutch in an automatic transmission, that is, a so-called clutch-to-clutch. It is configured to execute a shift. In the vehicle shift control apparatus described in Patent Document 1, the input shaft torque of the automatic transmission based on the drive request amount by the driver, the input shaft angular acceleration target value of the automatic transmission, the automatic transmission An output shaft torque target value of the automatic transmission is obtained based on the output shaft angular acceleration and the torque sharing rate of the engagement side clutch and the release side clutch. Next, the output shaft torque target value, the input shaft angular acceleration target value of the automatic transmission, the output shaft angular acceleration of the automatic transmission, the engagement side clutch that changes as the clutch-to-clutch shift progresses, and Based on the torque sharing ratio of the disengagement side clutch, the torque of the engagement side clutch and the disengagement side clutch in the torque phase and inertia phase using a common arithmetic expression in the torque phase and inertia phase in clutch-to-clutch shift Capacity is required, and clutch-to-clutch shifting is performed.

Japanese Patent No. 5928580

  As described above, Patent Document 1 discloses a control technique related to clutch-to-clutch shift. However, there is no detailed disclosure regarding a control technique for forming a predetermined shift stage by engaging a plurality of engagement elements from a neutral state in which a plurality of engagement elements or all the engagement elements are released. For example, when executing neutral control for inertial running of the vehicle with the automatic transmission set to neutral, or during EV running in which the hybrid vehicle is driven only by the output of the motor, the automatic transmission is neutral while the vehicle is running. It will be in the state of. In cases where the neutral control is terminated and the vehicle returns to the normal state, or in cases where the hybrid vehicle is shifted from EV traveling to HV traveling (or parallel traveling) with the output of the engine, a plurality of engaging elements are engaged during traveling. By combining, the automatic transmission is brought into a state where power can be transmitted. In such a case, if the engagement control of the engagement element and the output torque control of the engine are not properly executed, an engagement shock of the engagement element occurs during traveling. In addition, a judder phenomenon may be caused when the engaging elements are engaged. In this way, for vehicles that perform control to engage the plurality of engagement elements and return the automatic transmission to the power transmission state from the state where the plurality of engagement elements are released and the automatic transmission is neutral. In this case, there is still room for improvement in order to appropriately suppress the occurrence of engagement shock and judder.

  The present invention has been conceived by paying attention to the above technical problem, and automatically sets a neutral by releasing a plurality of engagement elements and performs power transmission by engaging a plurality of engagement elements. An object of the present invention is to provide a vehicle control device capable of appropriately suppressing the occurrence of engagement shock and judder for a vehicle equipped with a transmission.

  In order to achieve the above object, a vehicle control apparatus according to the present invention engages an engine, drive wheels, and at least two engagement elements capable of continuously changing a transmission torque capacity. An automatic transmission that transmits power between the engine and the driving wheel; and a controller that controls the engine and the automatic transmission; and based on a target driving force determined from a vehicle speed and a drive request operation by a driver In the vehicle control apparatus for controlling the driving torque output from the engine and the operation of the engagement element, the automatic transmission includes an input shaft, an output shaft, and at least a first clutch and a first clutch as the engagement element. Power transmission between the input shaft and the output shaft by releasing both the first clutch and the second clutch. The neutral is set to be shut off, and the first clutch and the second clutch are respectively engaged from the neutral state, thereby setting a predetermined gear position so that the power transmission is possible. The controller is configured so that, when the automatic transmission is in a state where the power transmission is possible from the neutral, the output shaft torque transmitted from the output shaft to the drive wheel side becomes a constant value. The first clutch is engaged by controlling the input shaft torque of the input shaft to which the drive torque is transmitted and the transmission torque capacity of the first clutch, respectively.

  In the vehicle control apparatus according to the present invention, the controller transmits the input shaft torque and the first clutch so that a ratio between the input shaft torque and the transmission torque capacity of the first clutch becomes a constant value. The first clutch may be engaged by controlling the torque capacity.

  In the vehicle control apparatus according to the present invention, after the first clutch is engaged as described above, the controller sets the target value of the angular acceleration of the input shaft when the second clutch is engaged. The second clutch may be engaged by controlling the input shaft torque and the transmission torque capacity of the second clutch so as to satisfy the target driving force at a predetermined target angular acceleration.

  In the vehicle control apparatus according to the present invention, a predetermined gear position is set by engaging at least two engaging elements of the automatic transmission, that is, at least the first clutch and the second clutch, and the automatic transmission Power transmission is enabled. The automatic transmission is neutralized by releasing both the first clutch and the second clutch. Therefore, compared with the case where only one engagement element is released and the neutral is set, drag loss when traveling with the automatic transmission set to neutral is reduced.

  Furthermore, in the vehicle control device of the present invention, when the automatic transmission is shifted from the neutral state to a state where power transmission is possible, the output shaft torque of the automatic transmission is constant before and after the engagement of the engagement element. Thus, the input shaft torque of the automatic transmission and the transmission torque capacity of the first clutch are controlled. For example, in an orthogonal coordinate system having the transmission torque capacity of the first clutch and the input shaft torque as coordinate axes, the intersection of a straight line when the output shaft torque is constant and a straight line when the input shaft angular acceleration is constant, The target value of the input shaft torque and the target value of the transmission torque capacity of the first clutch are used. Then, based on these target values, the input shaft torque and the transmission torque capacity of the first clutch are respectively controlled, and the first clutch is engaged. In other words, the input shaft torque and the transmission torque capacity of the first clutch are controlled so that the ratio between the input shaft torque and the transmission torque capacity of the first clutch becomes a constant value under a predetermined input shaft angular acceleration. Then, the first clutch is engaged. As a result, when the first clutch is engaged, the output shaft torque is constant before and after the engagement. Therefore, the first clutch can be appropriately engaged without causing an engagement shock.

  Further, when the second clutch is engaged after the first clutch is engaged, the target driving force of the vehicle is changed while changing the rotational speed of the input shaft of the automatic transmission under a predetermined target angular acceleration. In order to achieve this, the input shaft torque and the transmission torque capacity of the second clutch are respectively controlled. For example, in a Cartesian coordinate system using the transmission torque capacity of the second clutch and the input shaft torque as coordinate axes, a straight line that connects the conditions that enable the target angular acceleration and a straight line that connects the conditions that enable the target driving force. Is the target value of the input shaft torque and the target value of the transmission torque capacity of the second clutch. Then, based on these target values, the input shaft torque and the transmission torque capacity of the second clutch are respectively controlled, and the second clutch is engaged. As a result, when the second clutch is engaged, the output shaft torque is constant before and after the engagement. Therefore, the second clutch can be appropriately engaged without causing an engagement shock.

  Further, as described above, the input shaft torque and the transmission torque capacity of the first clutch, and the ratio of the input shaft torque and the transmission torque capacity of the second clutch are respectively constant. The torque and the transmission torque capacity of the first clutch and the transmission torque capacity of the second clutch can be set freely. Therefore, the differential rotation of the first clutch and the differential rotation of the second clutch can be appropriately controlled. As a result, it is possible to appropriately suppress the generation of clutch judder when engaging the engaging element.

  Therefore, according to the vehicle control device of the present invention, a vehicle equipped with an automatic transmission that releases a plurality of engagement elements to set a neutral position and engages the plurality of engagement elements to transmit power. It is possible to appropriately suppress the occurrence of engagement shock and judder.

It is a figure which shows an example of a structure of a vehicle made into the object of control by the vehicle control apparatus of this invention, and a control system. It is a flowchart for demonstrating an example of the control performed by the control apparatus of the vehicle of this invention. It is a time chart for demonstrating the behavior of the vehicle in the case of performing control shown by the flowchart of FIG. FIG. 3 is a diagram for explaining the control contents when the first clutch is engaged when the control shown in the flowchart of FIG. 2 is executed. FIG. 3 is a diagram for explaining control contents when a second clutch is engaged when the control shown in the flowchart of FIG. 2 is executed.

  Embodiments of the present invention will be described with reference to the drawings. The embodiment described below is merely an example when the present invention is embodied, and does not limit the present invention.

  The vehicle to be controlled in the embodiment of the present invention may be a conventional vehicle equipped with only an engine as a driving force source. Alternatively, a hybrid vehicle equipped with an engine and a motor as a driving force source may be used. FIG. 1 shows an example of a hybrid vehicle equipped with an engine and two motors. The vehicle to be controlled in the embodiment of the present invention includes an automatic transmission that transmits power between the engine and the drive wheels.

  A hybrid vehicle (hereinafter referred to as a vehicle) Ve shown in FIG. 1 includes an engine (ENG) 1, a first motor (MG1) 2, and a second motor (MG2) 3 as driving force sources. Furthermore, the vehicle Ve includes an automatic transmission (AT) 4, a detection unit 5, and a controller (ECU) 6 as other main components. In the example illustrated in FIG. 1, the vehicle Ve uses a first motor 2, an automatic transmission 4, a second motor 3, and a differential gear 7 to drive torque output from the engine 1 through a drive shaft 8 and driving wheels. 9 is transmitted.

  The engine 1 is, for example, an internal combustion engine such as a gasoline engine or a diesel engine, and is configured such that output adjustment and operation states such as starting and stopping are electrically controlled. In the case of a gasoline engine, the throttle valve opening, the amount of fuel supplied or injected, and the ignition timing are electrically controlled. In the case of a diesel engine, the fuel injection amount, the fuel injection timing, or the opening degree of a throttle valve in an EGR [Exhaust Gas Recirculation] system is electrically controlled.

  The first motor 2 is, for example, an electric motor such as a permanent magnet type synchronous motor or an induction motor, and mainly functions as a generator that generates electricity by being driven by receiving torque from the outside. . The first motor 2 is connected to the output shaft 1a of the engine 1, and is configured to be able to generate electric power by driving the first motor 2 by the engine 1. In other words, the first motor 2 converts part of the power output from the engine 1 into electric power. The first motor 2 may be a so-called motor generator that has both the function as a generator as described above and the function as a prime mover that is driven by supplying electric power and outputs motor torque. The first motor 2 is electrically controlled for output rotation speed and motor torque. In the case of a motor / generator, switching between the function as a generator and the function as a prime mover is electrically controlled.

  The second motor 3 is, for example, a permanent magnet type synchronous motor or an electric motor such as an induction motor, similar to the first motor 2 described above, and is mainly driven by being supplied with electric power. It functions as a prime mover that outputs torque. The second motor 3 is connected to an output shaft 11 of the automatic transmission 4 described later so that motor torque can be added. The second motor 3 may be a so-called motor / generator having both the function as the prime mover as described above and the function as the generator. The second motor 3 is electrically controlled for output rotation speed and motor torque. In the case of a motor / generator, switching between the function as a prime mover and the function as a generator as described above is electrically controlled.

  The automatic transmission 4 includes an input shaft 10, an output shaft 11, and a plurality of engagement elements (clutch / brake mechanism) 12. The automatic transmission 4 is connected to the output side of the engine 1. Specifically, the input shaft 10 of the automatic transmission 4 is connected to the output shaft 1 a of the engine 1 via the first motor 2. The output shaft 11 of the automatic transmission 4 is connected to a differential gear 7 that is a final reduction gear, and is configured to transmit the torque of the output shaft 11 to the left and right drive shafts 8 and drive wheels 9 by the differential gear 7. . The output shaft 11 of the automatic transmission 4 is connected to the second motor 3 that outputs motor torque for traveling as described above. The automatic transmission 4 is generally configured of, for example, a planetary gear mechanism (not shown) and a plurality of engagement elements 12 that are selectively engaged to set a predetermined gear stage (speed ratio). It is a typical stepped automatic transmission. Therefore, the automatic transmission 4 shifts the rotational speed of the input shaft 10 to which the output torque (drive torque) of the engine 1 is transmitted, and transmits the drive torque from the output shaft 11 to the drive wheel 9 side.

  The automatic transmission 4 according to the embodiment of the present invention has at least two engagement elements 12 capable of continuously changing the transmission torque capacity (clutch torque capacity). In the example shown in FIG. 1, the engaging element 12 includes a first clutch 12 a and a second clutch 12 b. Each of the first clutch 12a and the second clutch 12b is an engagement mechanism capable of continuously changing the clutch torque capacity. For example, a hydraulic friction clutch or a friction brake, or an electromagnetic clutch or It consists of a brake. The automatic transmission 4 according to the embodiment of the present invention sets a neutral that cuts off power transmission between the input shaft 10 and the output shaft 11 by releasing both the first clutch 12a and the second clutch 12b. Further, by engaging each of the first clutch 12a and the second clutch 12b, a predetermined gear position is set, and the power transmission between the input shaft 10 and the output shaft 11 is enabled.

  The first clutch 12a is disposed closer to the input shaft 10 than the second clutch 12b in the automatic transmission 4. The second clutch 12b is disposed in the automatic transmission 4 closer to the output shaft 11 than the first clutch 12a. Therefore, the torque of the input shaft 10 is transmitted to the first clutch 12a before the second clutch 12b. When the first clutch 12a is released, the torque of the input shaft 10 is not transmitted to the second clutch 12b. In the automatic transmission 4 according to the embodiment of the present invention, as will be described later, when a predetermined shift stage is set from the neutral state and power is transmitted between the input shaft 10 and the output shaft 11, The first clutch 12a and the second clutch 12b are respectively engaged in the order of the first clutch 12a and the second clutch 12b.

  The detection unit 5 detects or calculates at least the vehicle speed of the vehicle Ve, each operation state of the engine 1, the first motor 2, and the second motor 3, the operation state of the automatic transmission 4, and the like. Are collectively called. Therefore, the detection unit 5 typically includes a wheel speed sensor 5a that detects the rotational speeds of the drive wheels 9 and other wheels (not shown), and an engine rotational speed that detects the rotational speed of the output shaft 1a of the engine 1. Sensor 5b, first motor rotation speed sensor (or resolver) 5c for detecting the rotation speed of the first motor 2, second motor rotation speed sensor (or resolver) 5d for detecting the rotation speed of the second motor 3, automatic An input shaft rotational speed sensor 5e for detecting the rotational speed of the input shaft 10 of the transmission 4, an output shaft rotational speed sensor 5f for detecting the rotational speed of the output shaft 11 of the automatic transmission 4, and the clutch torque of the engagement element 12 A hydraulic sensor 5g for detecting the engagement hydraulic pressure for controlling the capacity is provided. In addition, for example, an accelerator position sensor 5h that detects an operation amount and an operation speed of an accelerator pedal by a driver, a shift device (not shown) that sets a shift stage of the automatic transmission 4, a traveling mode of the vehicle Ve, and the like. A shift position sensor 5i that detects the selected position, an acceleration sensor 5j that detects the acceleration of the vehicle Ve, and the like are included. And the detection part 5 is electrically connected with the controller 6 mentioned later, and outputs the electrical signal according to the detected value or calculated value of the above various sensors, apparatuses, etc. to the controller 6 as detection data.

  The controller 6 is an electronic control unit mainly composed of, for example, a microcomputer. In the example shown in FIG. 1, the engine 1, the first motor 2, the second motor 3, and the automatic transmission 4 are mainly used. To control each. Various data detected or calculated by the detection unit 5 is input to the controller 6. The controller 6 performs calculations using the various input data and data or calculation formulas stored in advance. The controller 6 outputs the calculation result as a control command signal, and controls the operations of the engine 1, the first motor 2, the second motor 3, and the automatic transmission 4 as described above. Has been. For example, the controller 6 sets the target driving force of the vehicle Ve based on the vehicle speed and the operation amount (driving request operation) of the accelerator pedal by the driver, and the engine 1 is set so that the target driving force is achieved. The driving torque to be output and the shift operation of the automatic transmission 4 are respectively controlled. Although FIG. 1 shows an example in which one controller 6 is provided, a plurality of controllers 6 may be provided for each device or device to be controlled, or for each control content.

  In a conventional vehicle equipped with the automatic transmission 4 as described above, by releasing any one of the plurality of engagement elements 12 that are engaged when setting a predetermined shift speed, The neutral of the automatic transmission 4 is set. For example, when executing neutral control for reducing loss due to engine friction torque, the automatic transmission 4 is set to neutral during traveling. Conventionally, when any one of the engagement elements 12 is released and the automatic transmission 4 is set to neutral as described above, the one that has been released when the neutral control is ended and the normal traveling state is restored. By engaging the two engaging elements 12, the automatic transmission 4 is brought into a power transmission state. Therefore, in that case, by appropriately controlling the differential rotation between the input shaft 10 side and the output shaft 11 side in one engagement element 12, torque fluctuation and engagement shock at the time of engagement can be prevented. can do.

For example, the inertia of the input shaft 10 of the automatic transmission 4 is engaged with I _e , the angular acceleration (input shaft angular velocity) of the input shaft 10 is d / dtω _e , and the torque (input shaft torque) of the input shaft 10 is engaged with T _e . transmission torque capacity (clutch torque capacity) of the T _c of the engaging element _12, and, when the torque of the output shaft 11 of the automatic transmission 4 (output shaft torque) to T _o, the automatic transmission 4 input shaft 10 and the output The following equation of motion is established for the axis 11.
Regarding the periphery of the input shaft 10 (before engagement): I _e × d / dtω _e = T _e −T _c
Regarding the output shaft 11 (before engagement): T _o = T _c
Respect around the output shaft 11 (After _{engagement): T} o = T _e
In the above equation of motion, if the input shaft angular acceleration d / dtω _e is constant,
Input shaft torque T _e = clutch torque capacity T _c
Next, the value of the output shaft torque T _o and after engagement with the front engagement of the engaging element 12 coincide. Therefore, for example, by engaging feedback control of the differential rotation of the engagement element 12 and engaging the engagement element 12, the engagement shock can be suppressed.

  On the other hand, in the vehicle Ve in the embodiment of the present invention, the neutral of the automatic transmission 4 is set by releasing at least two engaging elements 12, that is, at least the first clutch 12a and the second clutch 12b. Therefore, as described above, the automatic transmission 4 is set to neutral as compared with the conventional vehicle in which the neutral of the automatic transmission 4 is set in a state where any one of the other engagement elements 12 is engaged. The drag loss when the vehicle Ve is traveling is reduced, and the energy efficiency of the vehicle Ve is improved accordingly.

  However, when setting the neutral of the automatic transmission 4 by releasing the plurality of engagement elements 12 as in the vehicle Ve in the embodiment of the present invention, that is, when changing the automatic transmission 4 from the neutral to the power transmission state. When engaging a plurality of engagement elements 12, the relationship shown by the above equation of motion is not established. Therefore, in the same control as described above, there is a possibility that torque fluctuation or engagement shock during engagement may occur.

  Therefore, the control device for the vehicle Ve according to the embodiment of the present invention appropriately sets the engagement states of the first clutch 12a and the second clutch 12b when the automatic transmission 4 is in a state where power can be transmitted from neutral. It is configured to be able to control and suppress the occurrence of engagement shock and judder. Therefore, an example of the control executed by the controller 6 in the embodiment of the present invention will be described below.

  FIG. 2 is a flowchart showing an example of the control, which is executed when the vehicle Ve is running with both the first clutch 12a and the second clutch 12b released and the automatic transmission 4 set to neutral. The For example, it is executed when the automatic transmission 4 is set to neutral by the neutral control as described above. Alternatively, it is executed when the automatic transmission 4 is set to neutral and the vehicle is running on EV by the motor torque of the second motor 3.

  In the flowchart of FIG. 2, in step S <b> 1, it is determined whether or not there is an instruction to return from the neutral to the automatic transmission 4. For example, in order to end the neutral control as described above, it is determined whether or not there is an instruction to set a predetermined shift stage and set the automatic transmission 4 to the power transmission state from the state where the automatic transmission 4 is set to neutral. Is done. Alternatively, whether or not there is an instruction to shift from the state where the automatic transmission 4 is in the neutral state to the EV traveling state to the state in which the automatic transmission 4 is in the power transmission state and the vehicle 1 is HV traveling with the driving torque output by the engine 1. To be judged.

  If there is no return instruction from the neutral to the automatic transmission 4, and if a negative determination is made in step S1, this routine is temporarily terminated without executing the subsequent control. On the other hand, when there is a return instruction from neutral to the automatic transmission 4, if the determination in step S1 is affirmative, the process proceeds to step S2.

  In step S2, the engine 1 is started. For example, in order to improve the fuel efficiency of the vehicle Ve, the engine 1 that has stopped the combustion operation during the execution of the neutral control is started. Alternatively, in order to shift from EV traveling to HV traveling, the engine 1 that has stopped the combustion operation during EV traveling is started.

  Subsequently, in step S3, it is determined whether or not the differential rotation of the first clutch 12a has become zero. When the automatic transmission 4 is in the neutral state and the engine 1 is started and the rotational speed increases, the rotational speed of the input shaft 10 increases accordingly, and as a result, the differential rotation of the first clutch 12a decreases. In the control according to the embodiment of the present invention, the following engagement control of the first clutch 12a is started when the differential rotation of the first clutch 12a becomes zero.

  Therefore, this step S3 is repeatedly executed until the differential rotation of the first clutch 12a becomes zero. If it is determined affirmative in step S3 because the differential rotation of the first clutch 12a has become 0, the process proceeds to step S4.

In step S4, engagement control of the first clutch 12a is executed. The engagement control of the first clutch 12a, as before and after engaging the first clutch 12a, the output shaft torque T _o which transmitted from the output shaft 11 of the automatic transmission 4 to driving wheels 9 side becomes a constant value The torque of the input shaft 10 of the automatic transmission 4 to which the driving torque of the engine 1 is transmitted (that is, the input shaft torque T _e ) and the clutch torque capacity T _c1 of the first clutch 12a are respectively controlled. Note that when engaging the first clutch 12a, as described above, as the input shaft angular acceleration d / dtω _e of the input shaft 10 becomes the predetermined target angular acceleration, the input shaft torque T _e and the clutch torque capacity T _c1 Are controlled, and the first clutch 12a is engaged. That is, while the rotational speed of the input shaft 10 of the automatic transmission 4 is changed under the above target angular acceleration, so that the output shaft torque T _o is a constant value, the input shaft torque T _e and the clutch torque capacity T _c2 Are controlled respectively. The above target angular acceleration in this case is preset as a target value of the input shaft angular acceleration d / dtω _e when engaging the first clutch 12a.

  Subsequently, in step S5, it is determined whether or not the engagement of the first clutch 12a is completed. For example, the engagement state of the first clutch 12a can be determined based on the detection value of the hydraulic pressure sensor 5g that detects the engagement hydraulic pressure of the first clutch 12a.

  If the determination at Step S5 is negative because the engagement of the first clutch 12a has not been completed yet, the process returns to Step S4, and the control at the previous Steps S4 and S5 is repeated. That is, the control in step S4 and step S5 is repeatedly executed until the engagement of the first clutch 12a is completed. On the other hand, if it is determined affirmative in step S5 because the engagement of the first clutch 12a is completed, the process proceeds to step S6.

In step S6, the engagement control of the second clutch 12b is executed. In the engagement control of the second clutch 12b, the input shaft torque _Te and the clutch torque capacity _Tc2 of the second clutch 12b are respectively set under a predetermined target angular acceleration so as to realize the target driving force of the vehicle Ve. The second clutch 12b is engaged by being controlled. That is, the input shaft torque _Te and the clutch torque capacity _Tc2 of the second clutch 12b are set so as to satisfy the target driving force while changing the rotational speed of the input shaft 10 of the automatic transmission 4 under the target angular acceleration. Each is controlled. The above target angular acceleration in this case is preset as a target value of the input shaft angular acceleration d / dtω _e when engaging the second clutch 12b.

  Subsequently, in step S7, it is determined whether or not the engagement of the second clutch 12b is completed. For example, the engagement state of the second clutch 12b can be determined based on the detection value of the hydraulic pressure sensor 5g that detects the engagement hydraulic pressure of the second clutch 12b.

  If a negative determination is made in step S7 because the engagement of the second clutch 12b has not yet been completed, the process returns to step S6, and the control in the previous steps S6 and S7 is repeated. That is, the control in step S6 and step S7 is repeatedly executed until the engagement of the second clutch 12b is completed. When the engagement of the second clutch 12b is completed and an affirmative determination is made in step S7, this routine is once terminated.

  The behavior of the vehicle Ve when the control shown in the flowchart of FIG. 2 is executed as described above is shown in the time chart of FIG. The time chart of FIG. 3 shows a case where the traveling mode of the vehicle Ve is switched from EV traveling to HV traveling, for example. In the time chart of FIG. 3, before the time t1 when the engine 1 starts to start, the vehicle Ve is in an EV traveling state, and the automatic transmission 4 is neutral. Therefore, both the first clutch 12a and the second clutch 12b are released, and the clutch torque capacity is 0 in both cases.

  For example, when the engine 1 is started at time t1 due to an instruction to shift from EV traveling to HV traveling, the input shaft 10 of the automatic transmission 4 increases as the rotational speed (not shown) of the engine 1 increases. The rotation speed (input shaft rotation speed) begins to rise. As the input shaft speed increases, the differential rotation of the first clutch 12a gradually decreases. That is, the differential rotation of the first clutch 12a approaches zero. Then, at the timing (time t2) when the differential rotation of the first clutch 12a becomes zero, the engagement control of the first clutch 12a is started.

Engagement of the first clutch 12a, as described above, before and after the engagement of the first clutch 12a, so that the output shaft torque T _o of the automatic transmission 4 becomes a constant value, the input shaft torque T _e, And the clutch torque capacity T _c1 of the first clutch is controlled. For example, as shown in FIG. 4, the clutch torque capacity T _c1 of the first clutch _12a, and, in an orthogonal coordinate system with the coordinate axes input shaft torque T _e, and the straight line L1 in the case where the output shaft torque T _o is constant , an intersection a between the straight line L2 in the case of a constant input shaft angular acceleration d / dtω _e (the input shaft angular acceleration d / dtω _e to a predetermined target angular acceleration), the target value of the input shaft torque T _e and The target value of the clutch torque capacity T _c1 is set. Then, based on those target values, the input shaft torque _Te and the clutch torque capacity _Tc1 are respectively controlled, and the first clutch 12a is engaged. That is, in the engagement control of the first clutch 12a according to the embodiment of the present invention, the input shaft torque _Te and the input torque of the input shaft so that the ratio (T _e / T _c1 ) of the clutch torque capacity T _c1 becomes a constant value. The torque _Te and the clutch torque capacity T _c1 are respectively controlled, and the first clutch 12a is engaged.

  The target angular acceleration in the engagement control of the first clutch 12a is a constant set to a value suitable for engaging the first clutch 12a. The target angular acceleration is determined in advance based on, for example, results of running experiments or simulations.

As in the conventional example described above, the input shaft angular acceleration is d / dtω _e , the input shaft torque is T _e , the clutch torque capacity (transmission torque capacity) of the first clutch 12 a is T _c1 , and the automatic transmission 4 When the output shaft torque and T _o, the equation of motion about the input shaft 10 and the output shaft 11 of the automatic transmission 4 in the embodiment of the present invention, in a simplified manner, is expressed as follows.
Regarding the periphery of the input shaft 10 (before engagement): d / dtω _e = a ₁ × T _e −b ₁ × T _c1
Regarding the output shaft 11 (before engagement): T _o = a ₂ × T _e + b ₂ × T _c1
Regarding the output shaft 11 (after engagement): T _o = a ₃ × T _e
Note that a ₁ , a ₂ , a ₃ , b ₁ , and b ₂ are constants determined from mechanical characteristics of the automatic transmission 4 such as a gear ratio and inertia.

In the above equation of motion, the output shaft torque T _o before engagement is equal to the output shaft torque T _o after engagement.
a ₂ × T _e + b ₂ × T _c1 = a ₃ × T _e
From this equation,
_{T e / T c1 = b 2} / (a 3 -a 2)
Is obtained. In this relational expression, “b ₂ / (a ₃ −a ₂ )” is a constant.

Accordingly, the engagement of the first clutch 12a in the embodiment of the present invention, as the ratio between the input shaft torque T _e and the clutch torque capacity T _c1 is a constant value (constant), which input shaft torque T _e and by controlling the clutch torque capacity T _c1, respectively, it can be before and after the engagement of the first clutch 12a, the output shaft torque T _o constant. As a result, the first clutch 12a can be appropriately engaged without causing an engagement shock.

  When the engagement control of the first clutch 12a is executed as described above and the engagement of the first clutch 12a is completed at time t3, the engagement control of the second clutch 12b is started simultaneously or subsequently.

Engagement of the second clutch 12b, as as previously described, the input shaft angular acceleration d / dtω _e constant value (predetermined target angular acceleration), to realize the target driving force of the vehicle Ve, the input shaft torque T _e and the clutch torque capacity _{T c2} of the second clutch 12b respectively control. For example, as shown in FIG. 5, a straight line L3 connecting conditions for enabling the target angular acceleration to be realized in an orthogonal coordinate system having the clutch torque capacity T _c2 of the second clutch 12b and the input shaft torque _Te as coordinate axes. When the intersection B of the straight line L4 connecting the conditions that can realize the target driving force, the target value and the target value of the clutch torque capacity T _c2 of the input shaft torque T _e. Then, based on those target values, the input shaft torque _Te and the clutch torque capacity _Tc2 are respectively controlled, and the second clutch 12b is engaged.

The above target angular acceleration in the engagement control of the second clutch 12b, when engaging the second clutch 12b, the output shaft torque T _o of the automatic transmission 4 becomes constant before and after the engagement It is a constant set as follows. The target angular acceleration is determined in advance based on, for example, results of running experiments or simulations.

  When the engagement control of the second clutch 12b is executed as described above and the engagement of the second clutch 12b is completed at time t4, the automatic transmission 4 is set to a predetermined gear position, and the input shaft 10 and the output are output. The power can be transmitted to and from the shaft 11.

Accordingly, the engagement of the second clutch 12b of the embodiment of the present invention, when engaging the second clutch 12b is before and after the engagement of the second clutch 12b, the output shaft torque T _o constant be able to. As a result, the second clutch 12b can be properly engaged without causing an engagement shock.

Further, according to the control apparatus for a vehicle Ve in the embodiment of the present invention, as described above, the ratio between the input shaft torque T _e and the clutch torque capacity T _c1 of the first clutch 12a, and an input shaft torque T _e The input shaft torque T _e , the clutch torque capacity T _c1, and the clutch torque capacity T _c2 can be freely set under the condition that the ratio to the clutch torque capacity T _c2 of the second clutch is constant, respectively. Can do. Therefore, the differential rotation of the first clutch 12a and the differential rotation of the second clutch 12b can be appropriately controlled. As a result, it is possible to appropriately suppress the generation of clutch judder when the engaging element 12 of the automatic transmission 4 is engaged.

  Therefore, according to the control device for the vehicle Ve in the embodiment of the invention, at least the plurality of engaging elements 12 of the first clutch 12a and the second clutch 12b are released to set the neutral, and the first clutch 12a and the first clutch Engagement shocks and judder generation can be appropriately suppressed for a vehicle Ve equipped with an automatic transmission 4 that transmits power by engaging a plurality of engagement elements of the two-clutch 12b.

In the embodiment of the present invention, the engagement control of the first clutch 12a and the engagement control of the second clutch 12b as described above may be interchanged. That is, when the automatic transmission 4 set the predetermined shift stage from the neutral to the state where power transmission is possible, first of all, the target input shaft angular acceleration d / dtω _e when engaging the first clutch 12a The first clutch 12a is engaged by controlling the input shaft torque _Te and the clutch torque capacity _Tc1 of the first clutch so as to satisfy the target driving force of the vehicle Ve at a predetermined target angular acceleration predetermined as a value. You may let them. In this case, after engaging the first clutch 12a, so that the output shaft torque T _o is a constant value, specifically, the clutch torque capacity T _c2 of the input shaft torque T _e and the second clutch 12b as the ratio _(T e _{/ T c2)} is a constant value, the clutch torque capacity _{T c2} of the input shaft torque _{T e} and the second clutch 12b may be engaged with the second clutch 12b are controlled respectively.

  DESCRIPTION OF SYMBOLS 1 ... Engine (ENG), 1a ... (Engine) output shaft, 2 ... 1st motor (MG1), 3 ... 2nd motor (MG2), 4 ... Automatic transmission (AT), 5 ... Detection part, 5a ... Wheel speed sensor 5b Engine speed sensor 5c First motor speed sensor (resolver) 5d Second motor speed sensor (resolver) 5e Input shaft speed sensor 5f Output shaft speed sensor 5g: Hydraulic sensor, 5h: Accelerator position sensor, 5i ... Shift position sensor, 5j ... Acceleration sensor, 6 ... Controller (ECU), 7 ... Differential gear, 8 ... Drive shaft, 9 ... Drive wheel, 10 ... (Automatic shift) Input shaft, 11 ... output shaft of automatic transmission, 12 ... engagement element of (automatic transmission), 12a ... first clutch, 12b ... second clutch, Ve Vehicle.

Claims (1)

An automatic transmission for transmitting power between the engine and the drive wheels by engaging an engine, drive wheels, and at least two engagement elements capable of continuously changing the transmission torque capacity; And a controller for controlling the engine and the automatic transmission, respectively, for controlling a driving torque output from the engine and an operation of the engagement element based on a target driving force determined from a vehicle speed and a driving request operation by a driver. In a vehicle control device,
The automatic transmission is
An input shaft, an output shaft, and at least a first clutch and a second clutch as the engagement elements;
By releasing both the first clutch and the second clutch, a neutral that cuts off power transmission between the input shaft and the output shaft is set. From the neutral state, the first clutch and the second clutch are set. By engaging each of the two clutches, a predetermined gear position is set and the power transmission is enabled.
The controller is
The drive torque is transmitted so that the output shaft torque transmitted from the output shaft to the drive wheel side becomes a constant value when the automatic transmission is in a state where the power transmission is possible from the neutral. A control apparatus for a vehicle, wherein an input shaft torque of an input shaft and a transmission torque capacity of the first clutch are respectively controlled to engage the first clutch.

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