JP2009220661A - Controller for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller of a vehicle that prevents the generation of shock associated with engagement, even when a rotation speed of a rotary element on a synchronized side varies upon engagement of a dog clutch. <P>SOLUTION: A control means starts the engagement by moving one of a first rotary element and a second rotary element to a rotary shaft direction after synchronizing the first and second rotary elements by feedback control. Until engagement completion after the engagement start, a disturbance of torque control of a motor generator by contact between a tooth of the first rotary element and a tooth of the second rotary element is prevented by forbidding the feedback control. When detecting the rotation speed change of the second rotary element until the engagement completion after the engagement start, torque of the motor generator is adjusted such that a detected acceleration/deceleration amount is generated in the first rotary element. Thereby, the generation of the shock associated with the engagement can be prevented, and the engagement can be certainly performd. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle control device used in a power transmission device for a vehicle.

  Hybrid vehicles that include a power source such as an electric motor or a motor generator in addition to an internal combustion engine are known. In a hybrid vehicle, an internal combustion engine is operated in a highly efficient state as much as possible, while an excess or deficiency of driving force or engine braking force is compensated by an electric motor or a motor generator.

  In such a hybrid vehicle, one using a meshing clutch (dog clutch) having dog teeth in a clutch mechanism is known. Patent Document 1 describes a method of synchronizing at least one of a pair of rotating elements by rotating at least one of a pair of rotating elements having teeth with chamfer angles in a clutch synchronization device.

JP 7-269603 A

  On the other hand, there may be a case where the rotation speed of the rotating element on the side to be synchronized (synchronized side) changes due to the influence of the user operation or the like. In this case, there is a possibility that a shock may occur due to a collision with the tooth of the rotating element on the side to be synchronized (synchronous side) with the tooth of the rotating element on the synchronized side. Therefore, it is necessary to make the rotational speed of the rotating element on the synchronization side follow the change in the rotational speed on the synchronized side. However, Patent Document 1 does not discuss any case where the number of rotations on the synchronized side changes during engagement.

  The present invention has been made to solve the above-described problems, and even when the meshing clutch is engaged, even when the rotational speed of the rotating element on the synchronized side changes, the occurrence of a shock associated with the engagement is reliably prevented. It is an object of the present invention to provide a vehicle control device that can be engaged with the vehicle.

  In one aspect of the present invention, a motor generator, a first rotating element coupled to the motor generator, a second rotating element engaged with the first rotating element, and the first by feedback control. And a control means for performing a shift by engaging and releasing the teeth of the first and second rotating elements after synchronizing the second rotating elements. The means prohibits feedback control of the first rotating element from the start of engagement to the completion of engagement, and when the second rotating element is accelerated or decelerated, the acceleration / deceleration is performed by the motor generator. A torque corresponding to minutes is applied to the first rotating element.

  The vehicle control apparatus includes a motor generator, a first rotating element, a second rotating element, and control means. The motor generator rotationally drives the first rotating element with torque. The first rotating element and the second rotating element are, for example, clutch plates constituting a dog clutch, and can be engaged and released by the teeth of each other. The control means is realized by, for example, an ECU (Electronic Control Unit). The control means synchronizes the rotation speeds of the first rotation element and the second rotation element by feedback control, and then moves either the first rotation element or the second rotation element in the rotation axis direction. To start the engagement. The movement in the rotation axis direction is executed by an actuator, for example. From the start of engagement to the completion of engagement, feedback control is prohibited to prevent disturbance of torque control of the motor generator due to contact between the teeth of the first rotating element and the teeth of the second rotating element. Further, it is monitored whether or not there is a change in the rotational speed of the second rotating element between the start of engagement and the completion of the engagement. The torque of the motor generator is adjusted so that That is, the torque of the motor generator is feedforward controlled based on the detected degree of rotation speed change. By doing in this way, even when the rotation speed of the second rotation element changes during engagement, the rotation speed of the first rotation element can follow the rotation speed of the second rotation element. Therefore, it is possible to prevent the occurrence of shock accompanying the engagement and to execute the engagement reliably.

  One aspect of the above vehicle control device includes an engine, first and second motor generators, a power distribution mechanism connected to the engine and the first and second motor generators, and the power distribution mechanism. The motor generator is mounted on a hybrid vehicle including a connected fixed ratio transmission and an output shaft coupled to the fixed ratio transmission. The motor generator is the first or second motor generator, and the second The rotating element is connected to the output shaft. In this aspect, the vehicle control device is applied to a so-called multi-mode hybrid vehicle. The first or second motor generator of the multimode hybrid vehicle corresponds to the motor generator of the vehicle control device, and the second rotating element of the vehicle control device is the output shaft (axle) of the multimode hybrid vehicle. Connected to. Accordingly, the vehicle control device is preferably applied to a multi-mode hybrid vehicle.

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

[Device configuration]
FIG. 1 shows a schematic configuration of a drive device of a hybrid device to which the present invention is applied. The example of FIG. 1 is a drive device for a so-called multi-mode type hybrid vehicle including a fixed ratio transmission, and includes an engine 1, a first motor generator MG1, a second motor generator MG2, and an ECU (Electronic Control Unit). 10, a power distribution mechanism 20, a controller 41, and a power storage device 42. In FIG. 1, an engine 1 corresponding to a power source, a first motor generator MG 1, and a second motor generator MG 2 are connected to a power distribution mechanism 20. The first motor generator MG1 and the power distribution mechanism 20 are connected to the transmission 6. An output shaft 3 is connected to the transmission 6. The motor generators MG1 and MG2 are connected to a power storage device 42 such as a battery via a controller 41 such as an inverter, and are configured to operate as an electric motor or a generator under the control of the controller 41.

  The engine 1 is a heat engine that generates power by burning fuel, and examples thereof include a gasoline engine and a diesel engine. The first motor generator MG1 generates power mainly by receiving torque from the engine 1 and rotating, and reaction force torque accompanying power generation acts. By controlling the rotational speed of first motor generator MG1, the rotational speed of engine 1 changes continuously. Such a speed change mode is called a continuously variable speed change mode. The continuously variable transmission mode is realized by a differential action of a power distribution mechanism 20 described later.

  The second motor generator MG2 is a device that assists the driving torque or the braking force. When assisting the drive torque, the second motor generator MG2 receives power supply and functions as an electric motor. On the other hand, when assisting the braking force, the second motor generator MG2 functions as a generator that is rotated by torque transmitted from the drive wheels to generate electric power.

  The ECU (Electronic Control Unit) 10 includes a CPU, a ROM, a RAM, an A / D converter, an input / output interface, and the like (not shown). ECU 10 performs calculation using input data such as vehicle speed, required driving force, charge amount (SOC) of power storage device 42 and data stored in advance, and controls the motor generators MG1 and MG2 based on the calculation result. It outputs to the controller 41 as a command signal for performing the operation, and outputs a command signal for setting a predetermined operation mode or gear position by operating any of the clutches C1 to C3. The ECU 10 controls the engine 1, the first motor generator MG1, and the second motor generator MG2 by outputting a command signal to the controller 41 based on detection signals from various sensors. Examples of the various sensors include a crank angle sensor that detects the crank angle of the engine 1, and the rotational speeds of each of the first motor generator MG1 and the second motor generator MG2 (precisely “angular speed”, but in the following, There is a rotation speed sensor for detecting the rotation speed). ECU 10 obtains the number of revolutions of engine 1 based on the detection signal from the crank angle sensor, and the number of revolutions of first motor generator MG1 and the second motor generator based on the detection signal from the revolution number sensor. The number of rotations of MG2 is obtained. Therefore, the ECU 10 functions as a control unit in the present invention.

  The power distribution mechanism 20 includes a so-called double pinion planetary gear mechanism. Specifically, the power distribution mechanism 20 is meshed with the sun gear 23, the ring gear 21, the second pinion gear 24b meshed with the sun gear 23, and the second pinion gear 24b and the ring gear 21 arranged coaxially with each other. The first pinion gear 24a and the carrier 25 supporting the first pinion gear 24a and the second pinion gear 24b so as to be capable of rotating and revolving.

  The engine 1 is connected to a ring gear 21, and power from the engine 1 is transmitted to the ring gear 21. The second motor generator MG2 is connected to the first pinion gear 24a and the second pinion gear 24b via the carrier 25. The first pinion gear 24 a and the second pinion gear 24 b are connected to the input shaft 32 via the carrier 26. First motor generator MG1 is coupled to input shaft 31. The input shaft 31 is connected to the sun gear 23 via the clutch C3. The clutch C3 controls the connection between the input shaft 31 and the sun gear 23. When clutch C3 is turned on, the output of first motor generator MG1 is output to sun gear 23.

  The transmission 6 is a fixed ratio transmission and includes clutches C1 and C2. The clutch C1 controls the connection between the output shaft 3 and the input shaft 31, and the clutch C2 controls the connection between the output shaft 3 and the input shaft 32. The clutch C1 and the clutch C2 are dog clutches, and the clutch plate has dog teeth.

  When the clutch C1 is turned on, the output of the first motor generator MG1 is output to the output shaft 3 via the input shaft 31. When the clutch C2 is turned on, the output of the second motor generator MG2 is output to the output shaft 3 via the input shaft 32. The transmission 6 performs a shift in the fixed gear ratio mode by controlling the clutches C1 and C2 based on a control signal from the ECU 10. Specifically, the transmission 6 shifts between a state where the clutch C1 is turned off and the clutch C2 is turned on, and a state where the clutch C1 is turned on and the clutch C2 is turned off. I do. Hereinafter, the state in which the clutch C1 is turned off, the clutch C2 is turned on, and the output of the second motor generator MG2 is output to the output shaft 3 via the input shaft 32 is referred to as the “first speed” state. Further, a state where the clutch C1 is turned on, the clutch C2 is turned off, and the output of the first motor generator MG1 is output to the output shaft 3 via the input shaft 31 is a “second speed” state.

  A case of switching from “first speed” to “second speed” will be described. First, the transmission 6 starts from a state where the clutch C1 is turned off and the clutch C2 is turned on (a state of "1st speed"), and a state where both of the clutches C1 and C2 are turned on ("1st speed + 2nd speed"). ”State). Thereafter, the transmission 6 starts from a state in which both of the clutches C1 and C2 are turned on (a state of “1st speed + 2nd speed”) and a state in which the clutch C1 is turned on and the clutch C2 is turned off (“2nd speed”). ”State). In this way, the transmission 6 switches from “first speed” to “second speed”.

  Here, in the state of “first speed + second speed”, both the clutches C1 and C2 are turned on, so that the rotational speed of the clutch plate connected to the input shaft 31 in the clutch C1 and the clutch The rotational speed of the clutch plate connected to the input shaft 32 in C2 needs to match. That is, the rotational speed of the sun gear 23 and the rotational speed of the carrier 26 need to match. Therefore, the clutch plate connected to input shaft 31 in clutch C1 corresponds to the clutch plate connected to first motor generator MG1, and the clutch plate connected to input shaft 32 in clutch C2 is connected to motor generator MG2. It corresponds to a clutch plate.

[Dog clutch engagement control method 1]
Here, FIG. 2A schematically shows a configuration example of the dog clutch. FIG. 2A shows a synchronizing part 53b having an actuator 60 and movable (stroke) in the axial direction, and a synchronized part 53a engaged with the synchronizing part 53b. Synchronizing portion 53b corresponds to either a clutch plate connected to first motor generator MG1 or a clutch plate connected to second motor generator MG2, and synchronized portion 53a is on the output shaft 3 (axle) side. The clutch plate connected to is applicable. Therefore, switching from “1st speed” to “2nd speed” (strictly “1st speed + 2nd speed”) or switching from “2nd speed” to “1st speed” (strictly, “1st speed + 2nd speed”) In this case, the following description is included. In this case, a clutch plate (not shown) already engaged with the clutch plate on the output shaft 3 side (for example, in the case of switching from “1st speed” to “1st speed + 2nd speed”, the clutch connected to the first motor generator MG1) The plate is engaged with, for example, a clutch plate (not shown) different from the synchronized portion 53a connected to the output shaft 3 (axle) side. Hereinafter, the motor generator connected to the synchronization unit 53b is referred to as “synchronization side MG”.

  The synchronized portion 53a and the synchronized portion 53b include dog teeth 55a and 55b, respectively. The dog teeth 55a and 55b have a chamfer 55x located in a triangular shape, that is, a broken line frame.

  When switching between “1st speed” and “2nd speed”, the ECU 10 confirms that the rotations of the synchronized portion 53a and the synchronized portion 53b coincide with each other, and then starts the operation of the actuator 60 to perform engagement. . Hereinafter, starting the operation of the actuator 60 for engaging is expressed as “starting engagement”, and the synchronized portion 53a and the synchronizing portion 53b are completely engaged, and the operation of the actuator 60 is ended. Expressed as “complete engagement”.

  At the start of engagement, it is preferable to start the engagement by controlling the phase of the dog teeth 55a of the synchronized portion 53a and the dog teeth 55b of the synchronized portion 53b, that is, the specified meshing position. However, it is usually difficult to align the phases of the dog teeth 55a and the dog teeth 55b due to the influence of a disturbance or the like. Therefore, the ECU 10 utilizes the shape of the chamfer 55x and operates the actuator 60 when the rotational speeds coincide with each other, and pushes the dog teeth 55b of the synchronization portion 53b into the grooves of the dog teeth 55a of the synchronized portion 53a. . FIG. 3B is a schematic diagram when the engagement is performed using the chamfer 55x. As shown in FIG. 3B, the engagement between the dog teeth 55a and the dog teeth 55b is realized by meshing the dog teeth 55a and the dog teeth 55b with hardware so as to rub the chamfers 55x. ing. As described above, the ECU 10 can execute the engagement of the dog clutch by adjusting only the rotation speed.

  However, when the chamfers 55x of the dog teeth 55a and the dog teeth 55b come into contact with each other and engage with each other in the above-described engagement process, the dog teeth 55a and the chamfers 55x of the dog teeth 55b are respectively engaged. A relatively reverse rotational force (reaction force) is generated, and the relative position of the dog teeth 55b changes. Then, the rotation speed sensor detects the change in the relative position of the synchronization unit 55b described above as the change in the rotation number of the synchronization unit 55b, and transmits the detection result to the ECU 10. Then, the ECU 10 performs feedback control for correcting the above-described change in the rotational speed even though the rotational speeds of the synchronized portion 53a and the synchronous portion 53b are actually the same. As a result of adjusting the torque to be output to the synchronization side MG by feedback control (hereinafter referred to as “synchronization side MG torque”), the rotation speed of the synchronization unit 53b changes. Thereby, a shock may occur between the synchronization unit 53a and the synchronization unit 53b, and drivability may be deteriorated.

  This will be further described with an example. FIG. 3 shows a graph of changes in the rotational speed difference (hereinafter simply referred to as “rotational speed difference”) between the synchronized portion 53a and the synchronous portion 53b during engagement and the time-dependent change of the synchronization-side MG torque. As shown in FIG. 3, in the period A, the ECU 10 controls the rotational speed difference to be zero by adjusting the output of the synchronization side MG torque. Then, after the rotational speed difference becomes 0 and the ECU 10 starts to be engaged, that is, in the period B in FIG. 3, the ECU 10 engages the dog teeth 55a and the dog teeth 55b so as to slide with each other. The synchronization-side MG torque is adjusted by feedback control for correcting the detected rotational speed difference. Thereby, after the dog teeth 55a and the dog teeth 55b are engaged with each other, unnecessary torque is applied to the synchronization portion 55b side, and a shock is generated.

  Therefore, in the present embodiment, the above problem is solved by stopping the feedback control from the start of engagement until the completion of engagement. That is, the ECU 10 applies unnecessary torque to the synchronization side MG due to the rotational speed difference detected by the rotational speed sensor when the dog teeth 55a and the dog teeth 55b are engaged with each other so as to slide. To prevent. Specifically, after the synchronization between the synchronized portion 53a and the synchronized portion 53b is completed and the engagement is started, the ECU 10 does not reflect the change in the rotational speed at the synchronized portion 53b in the torque control of the synchronized MG. Like that. By doing in this way, generation | occurrence | production of the shock during an engagement process or after an engagement process can be prevented, and the deterioration of drivability can be prevented. Hereinafter, the engagement control performed by the ECU 10 is referred to as “engagement control method 1”.

  Next, the processing flow of the engagement control method 1 will be described using a flowchart. FIG. 4 is a flowchart showing a processing procedure of the engagement control method 1 performed by the ECU 10. The flowchart shown in FIG. 4 is repeatedly executed by the ECU 10.

  First, the ECU 10 monitors whether there is a shift request, that is, a dog clutch engagement request (step S1). If there is no shift request (step S1; No), the ECU 10 does not particularly perform the engagement process of the dog clutch, and continues control during normal travel (step S2).

  On the other hand, when there is a shift request (step S1; Yes), the ECU 10 determines whether the actuator can be operated (step S3). Specifically, the ECU 10 determines whether the rotation speeds of the synchronized portion 53a and the synchronization portion 53b output from the rotation speed sensor are within a predetermined rotation speed difference. When the rotational speed difference is greater than or equal to a predetermined value (step S3; No), the ECU 10 feedback-controls the torque of the synchronization side MG so that the rotational speed of the synchronization section 53b matches the rotational speed of the synchronized section 53a (step S4). ). Hereinafter, the above-described feedback control is referred to as “rotation synchronization feedback control”.

  When the rotational speed difference becomes equal to or smaller than the predetermined value (step S3; Yes), the ECU 10 starts the engagement and operates the actuator 60. At this time, the ECU 10 prohibits the rotation synchronization feedback control. Then, the ECU 10 controls the synchronization side MG torque so as to hold the previous value, that is, the torque value at the time when the rotational speed is determined to be equal to or less than the predetermined value in Step S3 (Step S5). Then, the ECU 10 continues the process according to step S5 until the engagement is completed (step S6, step S5). That is, the ECU 10 prohibits the rotation synchronization feedback control until the engagement is completed. Thereby, ECU10 can prevent generation | occurrence | production of the shock by unnecessary torque application, when engaging so that dog clutches may slip.

[Dog clutch engagement control method 2]
In the dog clutch engagement control method 1 described above, after the rotation speed difference is determined to be equal to or smaller than the predetermined value in step S3, that is, after the engagement is started, the rotation speed of the synchronized portion 53a is maintained while the actuator 60 is being operated. Is constant, the ECU 10 has stopped the rotation synchronization feedback control.

  However, when there is a user request such as when the user steps on the accelerator, there is a possibility that the rotation speed of the synchronized portion 53a may change even during the engagement process. In this case, since the ECU 10 stops the rotation synchronization feedback control, the ECU 10 cannot make the rotation speed of the synchronization section 53b follow the rotation speed change of the synchronized section 53a as requested by the user. As a result, before the dog teeth 55a and 55b are engaged with each other, that is, as shown in FIG. Cannot be executed. In addition, after the dog teeth 55a and 55b are engaged with each other, that is, as shown in FIG. 2B, in a state where the synchronized portion 53a and the synchronized portion 53b overlap each other, the dog teeth 55a and 55b are in between. A shock will occur.

  Therefore, in a new engagement control method (hereinafter referred to as “engagement control method 2”), when the rotational speed of the synchronized portion 53a changes while the actuator 60 is being operated, feedback control is performed. Instead, this problem is solved by performing feedforward control.

  This will be specifically described below. As shown in the above-described engagement control method 1, in the present invention, after the difference in rotational speed between the synchronized portion 53a and the synchronized portion 53b becomes less than a predetermined value, that is, after the engagement is started, feedback control is performed until the engagement is completed. To stop. Therefore, once it is determined that the rotational speed difference is equal to or less than the predetermined value, only the rotational speed of the synchronized portion 53a is monitored, and when there is an increase or decrease, the rotational speed of the synchronizing portion 53b is increased or decreased by the increase or decrease. Thus, ECU10 adjusts the torque of synchronous side MG. That is, the ECU 10 performs feedforward control during the engagement process. Specifically, when the rotation speed difference is determined to be equal to or less than a predetermined value and torque is generated in the synchronized portion 53a due to a user request or the like while performing engagement control, Torque is applied to the synchronization unit 53b. As a result, the same torque is applied to the synchronized portion 53a and the synchronized portion 53b, so that the relative rotational speed of the both does not change, and a shock is prevented from occurring between the dog teeth 55a and 55b. it can.

  Next, the processing flow of the engagement control method 2 will be described using a flowchart. FIG. 5 is a flowchart showing a processing procedure of the engagement control method 2 performed by the ECU 10. The flowchart shown in FIG. 5 is repeatedly executed by the ECU 10.

  First, steps S101 to S104 perform the same processing as steps S1 to S4 in the flowchart of FIG. That is, the ECU 10 performs normal running control until a shift request is made (steps S101 and S102), and if there is a shift request, performs ECU synchronous control until the rotational speed difference becomes a predetermined value or less (step S103, step S103). Step S104).

  When the rotational speed difference becomes equal to or smaller than the predetermined value (step S103; Yes), the ECU 10 prohibits the rotation synchronization feedback control and activates the actuator 60. The ECU 10 monitors whether the rotational speed of the synchronized portion 53a is changed even during the operation of the actuator 60. When detecting a change in the rotational speed, the ECU 10 adds the synchronization side MG torque by the amount of acceleration (including the amount of deceleration) of the synchronized portion 53b, and synchronizes the rotational speed (step S105).

Specifically, when the angular velocity of the synchronized portion 53a is Δω _out , the moment of inertia applied to the synchronization side MG is Im _Nout , and the previous value of the synchronization side MG torque is Tmg _before , the update value Tmg _after of the rotation side MG torque is
Δω _out × Im _Nout + Tmg _before → Tmg _after equation (1)
And can be calculated. Here, the ECU 10 calculates the angular velocity Δω _out of the synchronized portion 53a, for example, by continuously monitoring the rotational speed of the synchronized portion 53a. In addition, the ECU 10 holds a value calculated or measured in advance for the inertia moment Im _Nout .

Next, the ECU 10 stores the calculated update value Tmg _after of the rotation side MG torque in the previous value Tmg _before (step S106). As a result, while the rotation speed variation of the synchronized portion 53a due to a user request or the like continues, only the change from the previous rotation side MG torque update value needs to be adjusted in the next process.

  And ECU10 performs the process of step S105 and step S106 until engagement is completed (step S107, step S105, step S106). That is, step S105 and step S106 are executed by the ECU 10 each time a change in the rotational speed of the synchronized portion 53a is detected. By executing the above process, even when the rotation speed of the synchronized portion 53a changes during the engagement process due to a user request such as when the user steps on the accelerator, the occurrence of a shock at the time of engagement is prevented. It becomes possible.

It is a figure showing a schematic structure of a hybrid vehicle concerning an embodiment. It is the figure which showed the dog clutch typically. It is a figure which shows the graph of the rotation speed difference at the time of engagement, and the change of a synchronous MG torque. 3 is a flowchart showing a flow of processing according to an engagement control method 1. 5 is a flowchart showing a flow of processing according to an engagement control method 2.

Explanation of symbols

MG1, MG2 Motor generator 1 Engine 3 Output shaft 6 Transmission 20 Power distribution mechanism 53a Synchronized part 53b Synchronizing part 55a, 55b Dog teeth 55x Chamfer 60 Actuator

Claims (2)

A motor generator;
A first rotating element coupled to the motor generator;
The second rotating element engaged with the first rotating element is engaged with the teeth of the first and second rotating elements after the first and second rotating elements are synchronized by feedback control. And a control means for performing a shift by releasing the vehicle, and a vehicle control device comprising:
The control means prohibits feedback control of the first rotating element from the start of engagement to the completion of engagement, and when the second rotating element is accelerated or decelerated, the motor generator causes the motor generator to A vehicle control device that applies torque corresponding to acceleration / deceleration to the first rotating element. An engine, first and second motor generators, a power distribution mechanism connected to the engine and the first and second motor generators, a fixed ratio transmission connected to the power distribution mechanism, and the fixed Mounted on a hybrid vehicle having an output shaft coupled to the specific transmission,
The motor generator is the first or second motor generator;
The vehicle control device according to claim 1, wherein the second rotating element is coupled to the output shaft.

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