WO2012131959A1

WO2012131959A1 - Vehicle control system

Info

Publication number: WO2012131959A1
Application number: PCT/JP2011/058136
Authority: WO
Inventors: 高橋　知也; 幸男豊良; 香治村上
Original assignee: トヨタ自動車株式会社
Priority date: 2011-03-30
Filing date: 2011-03-30
Publication date: 2012-10-04
Also published as: DE112011105107T5; DE112011105107B4; JP5648739B2; CN103442958B; CN103442958A; JPWO2012131959A1

Abstract

A vehicle control system is provided with: an engine (10); a motor/generator (20); a manual transmission (30), or the like, capable of transmitting torque between the drive wheels (WL, WR), and the engine (10) and motor/generator (20); a gearshift device (81) for the manual transmission (30); a clutch (50) capable of enabling/preventing the transmission of torque between the engine (10) and the motor/generator (20), and between the engine (10) and the drive wheels (WL, WR); and a clutch pedal (51). Therein, when starting the stopped engine (10) through engagement of the clutch (50), by operating the gearshift device (81) and the clutch pedal (51) while driving, the motor/generator (20) outputs assist torque in an amount such that a driver does not feel any deceleration, and then when the torque volume of the clutch (50) increases to the level of the crank torque for starting revolutions of the engine (10), assist torque in a smaller volume than the torque volume is outputted to the motor/generator (20).

Description

Vehicle control system

The present invention comprises an engine using a mechanical power source, comprising a mechanical power source powered by mechanical energy, an electric power source powered by mechanical energy converted from electrical energy, and a power connection / disconnection device disposed therebetween. A driving mode, an EV driving mode using an electric power source, and a hybrid driving mode using a mechanical power source and an electric power source are switched manually by a driver's power connection / disconnection device and the driving mode switching device. The present invention relates to a vehicle control system.

2. Description of the Related Art Conventionally, a vehicle including a mechanical power source and an electric power source as power sources for driving wheel driving, and a power connection / disconnection device disposed between the mechanical power source and the electric power source is known. This type of vehicle is disclosed in, for example,

Patent Documents

1 and 2 below. In Patent Document 1, when starting the engine (mechanical power source) while traveling with such a vehicle, the torque capacity at the time of automatic engagement control of the clutch (power connection / disconnection device) is added to the target drive torque, A technique is described that reduces the shock at the time of clutch engagement by performing drive control of the motor (electric power source) with this added value as the target motor torque. Further, in Patent Document 2, assist control is performed by a motor so as to output a target motor torque that is set so that the inertia of the engine is absorbed when switching from the EV traveling mode to the engine traveling mode during traveling in such a vehicle. A technique for starting the engine is described.

JP 2010-202151 A JP 2002-349309 A

By the way, in the vehicle disclosed in Patent Document 1, the clutch is automatically controlled by the electronic control device regardless of whether or not the driver intends to engage the clutch. For this reason, when starting the engine of this vehicle, in order not to give the driver a sense of incongruity, the shock at the time of clutch engagement is reduced by the output of the assist torque of the motor considering the torque capacity of the clutch. It is preferable to make it difficult for the driver to recognize the combined action. However, in a vehicle in which switching between the engine travel mode and the EV travel mode is manually performed together with the driver's clutch operation, when the technique of Patent Document 1 is applied, when the engine is started during traveling, the own clutch engagement is performed. Even though the motor torque is transmitted to the engine by the operation and the engine speed is increased, the driver feels uncomfortable without being able to sense the vehicle's deceleration feeling associated with the clutch engagement. A scene where the engine cannot be started occurs.

Therefore, the present invention improves the disadvantages of the conventional example, eliminates the driver's uncomfortable feeling associated with the operation of the power connection / disconnection device when starting the mechanical power source during traveling, and ensures that the mechanical power source is used. It is an object of the present invention to provide a vehicle control system that can be started.

To achieve the above object, the present invention provides a mechanical power source powered by mechanical energy, an electrical power source powered by mechanical energy converted from electrical energy, the mechanical power source, the electrical power source, and a drive wheel. Between the mechanical power source and the electric power source, a torque transmitting device capable of transmitting torque between the first power device, a first operating device for a driver to manually change the torque transmission mode of the torque transmitting device, and the mechanical power source A torque connecting / disconnecting device capable of connecting / disconnecting torque transmission between the mechanical power source and the driving wheel, and a second operating device when the driver manually operates the connecting / disconnecting operation of the torque connecting / disconnecting device, And operating the first operating device and the second operating device during traveling to transmit the torque to the mechanical power source in accordance with the engaging operation of the torque connecting / disconnecting device and to stop the mechanical power Decelerate to driver when starting source When an assist torque having a magnitude not to be felt is output to the electric power source and the torque capacity of the torque connecting / disconnecting device increases to the rotation start cranking torque of the mechanical power source, an assist torque smaller than the torque capacity is applied to the electric power source. It is characterized by being output to a power source.

Here, it is desirable that the assist torque when the torque capacity is smaller than the rotation start cranking torque is set to a magnitude corresponding to the torque capacity.

In the vehicle control system according to the present invention, the driver feels a sense of deceleration by the assist torque output from the electric power source until the torque capacity of the torque connecting / disconnecting device reaches the rotation start cranking torque of the mechanical power source. Therefore, it is possible to eliminate the driver's uncomfortable feeling associated with the occurrence of deceleration before the rotational speed of the mechanical power source starts to increase. In addition, when the torque capacity of the torque connection / disconnection device reaches the rotation start cranking torque of the mechanical power source, the control system outputs an assist torque smaller than the torque capacity to the electric power source, thereby Since the driver can get a feeling of deceleration as the rotational speed increases, the driver does not feel uncomfortable. Thus, according to this control system, the driver is not given a sense of incongruity, so that the engine can be started reliably.

FIG. 1 is a diagram illustrating an example of a hybrid vehicle to which a vehicle control system according to the present invention is applied. FIG. 2 is a diagram illustrating an example of the speed change operation device and the EV travel mode switching device when the neutral state is selected. FIG. 3 is a diagram illustrating an example of the shift operation device and the EV travel mode switching device when the EV travel mode is selected. FIG. 4 is a diagram illustrating another example of the speed change operation device. FIG. 5 is a diagram illustrating the relationship between cranking torque and engine speed. FIG. 6 is a diagram for explaining the relationship between the pedal operation amount and the clutch torque capacity. FIG. 7 is a flowchart for explaining the arithmetic processing operation related to the assist torque at the time of engine restart. FIG. 8 is a time chart when the engine is restarted. FIG. 9 is a diagram for explaining the relationship between the clutch torque capacity and the assist torque. FIG. 10 is a flowchart illustrating another form of the arithmetic processing operation related to the assist torque at the time of engine restart.

Embodiments of a vehicle control system according to the present invention will be described below in detail with reference to the drawings. The present invention is not limited to the embodiments.

[Example]
An embodiment of a vehicle control system according to the present invention will be described with reference to FIGS.

The vehicle to which the control system according to the present invention is applied includes a mechanical power source powered by mechanical energy, an electrical power source powered by mechanical energy converted from electrical energy, the mechanical power source, the electrical power source, and a drive wheel. Between the mechanical power source and the electric power source, and between the mechanical power source and the mechanical power source, the first operating device for the driver to change the torque transmission form of the torque transmission device by manual operation, and the mechanical power A hybrid vehicle including a torque connecting / disconnecting device capable of connecting / disconnecting torque transmission between the power source and the drive wheel, and a second operating device when the driver manually operates the connecting / disconnecting operation of the torque connecting / disconnecting device.

First, an example of this hybrid vehicle will be described with reference to FIG. Reference numeral 1 in FIG. 1 indicates a hybrid vehicle of the present embodiment. The hybrid vehicle 1 exemplified here uses an engine travel mode using only the power of the mechanical power source, an EV travel mode using only the power of the electric power source, and powers of both the mechanical power source and the electric power source. It is configured so that the driver can manually switch between the hybrid travel mode.

The hybrid vehicle 1 includes an engine 10 that outputs mechanical power (engine torque) from an output shaft (crankshaft) 11 as a mechanical power source. The engine 10 may be an internal combustion engine, an external combustion engine, or the like. The operation of the engine 10 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 101.

Further, the hybrid vehicle 1 includes a motor, a generator capable of powering driving, or a motor / generator capable of driving both powering and regeneration as an electric power source. Here, the motor / generator 20 will be described as an example. The motor / generator 20 is configured, for example, as a permanent magnet AC synchronous motor, and its operation is controlled by a motor / generator electronic control device (hereinafter referred to as “motor / generator ECU”) 102. . During power running, it functions as a motor (electric motor), converts electrical energy supplied via the secondary battery 25 and the inverter 26 into mechanical energy, and outputs mechanical power (motor power running torque) from the rotating shaft 21. To do. On the other hand, at the time of regenerative driving, it functions as a generator (generator) and converts mechanical energy into electrical energy when mechanical power (motor regenerative torque) is input from the rotary shaft 21, and power is supplied via the inverter 26. Is stored in the secondary battery 25.

The hybrid vehicle 1 is provided with a battery monitoring unit 27 that detects a state of charge (SOC) of the secondary battery 25. The battery monitoring unit 27 transmits to the motor / generator ECU 102 a signal related to the detected state of charge of the secondary battery 25 (in other words, a signal related to the remaining capacity amount (SOC amount)). The motor / generator ECU 102 determines the charging state of the secondary battery 25 based on the signal, and determines whether or not the secondary battery 25 needs to be charged.

Further, the hybrid vehicle 1 is provided with a torque transmission device including a stepped manual transmission 30 or the like that is speed-changed by a speed change operation device 81 as a first operation device described later. As described above, the torque transmission device can transmit torque between the engine 10 and the drive wheels WL and WR and between the motor / generator 20 and the drive wheels WL and WR. The motive power (engine torque and motor power running torque) of the engine 10 and the motor / generator 20 is transmitted to the drive wheels WL and WR as a driving force through this torque transmission device.

The manual transmission 30 includes an input shaft 41 to which engine torque is input, an output shaft 42 that is disposed in parallel to the input shaft 41 at an interval and outputs torque to the drive wheels WL and WR, Is provided.

The engine torque is input to the input shaft 41 through a clutch 50 as a power connection / disconnection device. The clutch 50 includes an engaged state in which the output shaft 11 and the input shaft 41 of the engine 10 are coupled, and a released state (disconnected state) in which the output shaft 11 and the input shaft 41 are released (disconnected) from the engaged state. For example, a friction clutch device configured to be able to switch between.

The engagement state referred to here is a state where torque can be transmitted between the output shaft 11 and the input shaft 41, and is divided into a full engagement state and a semi-engagement state. The completely engaged state is a state where the rotation of the output shaft 11 and the input shaft 41 is synchronized. The half-engaged state is a state from when the output shaft 11 and the input shaft 41 start to be engaged until these rotations are synchronized, that is, a state during the engagement operation of the clutch 50, or synchronization of the rotations. This is a state from the state until the output shaft 11 and the input shaft 41 are completely disconnected, that is, a state during the releasing operation of the clutch 50. The released state is a state in which torque cannot be transmitted between the output shaft 11 and the input shaft 41.

The clutch 50 enables torque transmission between the engine 10 and the drive wheels WL and WR via the manual transmission 30 or the like in the engaged state, and disables torque transmission therebetween in the released state. In addition, the clutch 50 enables torque transmission between the engine 10 and the motor / generator 20 via the manual transmission 30 in the engaged state, while disabling torque transmission therebetween in the released state. The clutch 50 is mechanically switched via a link mechanism, a wire, or the like in accordance with the operation of the clutch pedal 51 (second operation device) by the driver in the switching operation between the engaged state and the released state (that is, the connecting / disconnecting operation of the clutch 50). To be done.

In this embodiment, the rotary shaft 21 of the motor / generator 20 is connected to the output shaft 42 via a gear pair 60 as an EV gear. The gear pair 60 includes a first gear 61 and a second gear 62 that are in mesh with each other. The first gear 61 is attached so as to rotate integrally with the rotating shaft 21 of the motor / generator 20. On the other hand, the second gear 62 has a larger diameter than the first gear 61 and is attached to the output shaft 42 of the manual transmission 30 so as to rotate integrally. As a result, the gear pair 60 operates as a reduction gear when torque is input from the rotating shaft 21 side of the motor / generator 20, while rotating torque is input from the output shaft 42 side of the manual transmission 30. Operates as a speed increasing device. Accordingly, when the motor / generator 20 is driven by power running, the motor power running torque is transmitted to the manual transmission 30 via the gear pair 60 functioning as a reduction gear. In contrast, when the motor / generator 20 is regeneratively driven, the output torque from the output shaft 42 of the manual transmission 30 is transmitted to the rotor of the motor / generator 20 via the gear pair 60 that functions as a speed increasing device. Is done. Here, the gear pair 60 is in any position on the shift gauge 81b, that is, a shift lever 81a, which will be described later, that is, in the shift positions 1 to 5, R, the EV travel mode selection position EV, or the neutral position. Assume that they are engaged.

Further, the manual transmission 30 exemplified here has five forward speeds and one reverse speed, and the first speed gear stage 31, the second speed gear stage 32, the second speed stage as the forward speed stages. A third gear stage 33, a fourth gear stage 34, and a fifth gear stage 35 are provided, and a reverse gear stage 39 is provided as a reverse gear stage. The forward shift speed is configured such that the gear ratio decreases in the order of the first speed gear stage 31, the second speed gear stage 32, the third speed gear stage 33, the fourth speed gear stage 34, and the fifth speed gear stage 35. is doing. Note that the manual transmission 30 in FIG. 1 is a simple description of the configuration, and the arrangement of each gear stage is not necessarily in the form of FIG.

In the power transmission device of the present embodiment, the engine torque input to the input shaft 41 is set to any one of the gear positions (gear stages 31 to 35, 39) by engaging the clutch 50. And is transmitted to the output shaft 42. In this power transmission device, the motor power running torque is transmitted to the output shaft 42. In this power transmission device, the torque output from the output shaft 42 is decelerated by the final reduction mechanism 71 and transmitted to the driving wheels WL and WR as a driving force via the differential mechanism 72.

Here, the first speed gear stage 31 is constituted by a gear pair of a first speed drive gear 31a and a first speed driven gear 31b that are in mesh with each other. The first speed drive gear 31 a is disposed on the input shaft 41, while the first speed driven gear 31 b is disposed on the output shaft 42. As for the second speed gear stage 32 to the fifth speed gear stage 35, the second speed drive gear 32a to fifth speed drive gear 35a and the second speed driven gear 32b to fifth speed driven are the same as the first speed gear stage 31. A gear 35b is provided.

On the other hand, the reverse gear stage 39 includes a reverse drive gear 39a, a reverse driven gear 39b, and a reverse intermediate gear 39c. The reverse drive gear 39 a is disposed on the input shaft 41, and the reverse driven gear 39 b is disposed on the output shaft 42. The reverse intermediate gear 39c is in mesh with the reverse drive gear 39a and the reverse driven gear 39b, and is disposed on the rotation shaft 43.

In the configuration of the manual transmission 30, one of the drive gears of each gear stage is disposed so as to rotate integrally with the input shaft 41, while the remaining drive gear is relative to the input shaft 41. Are arranged to rotate relative to each other. In addition, the driven gear of each shift stage is arranged so that any one of them is rotated integrally with the output shaft 42, while the rest is arranged so as to rotate relative to the output shaft 42. The

The input shaft 41 and the output shaft 42 are provided with sleeves (not shown) that move in the axial direction in accordance with the driver's speed change operation. The sleeve on the input shaft 41 is disposed between the drive gears of the two shift stages that can rotate relative to the input shaft 41. On the other hand, the sleeve on the output shaft 42 is disposed between the driven gears of the two gears that can rotate relative to the output shaft 42. The sleeve moves in the axial direction via a link mechanism or a fork (not shown) connected to the speed change operation device 81 when the driver operates the speed change operation device 81. Then, the moved sleeve rotates the drive gear and the driven gear, which can be relatively rotated, located in the moved direction, together with the input shaft 41 and the output shaft 42. In the manual transmission 30, the sleeve moves in a direction corresponding to the speed change operation of the driver's speed change operation device 81, thereby switching to a gear position according to the speed change operation or a neutral state (that is, the input shaft 41. And a state in which torque cannot be transmitted between the output shaft 42 and the output shaft 42).

In this hybrid vehicle 1, an EV travel mode switching device operated by a driver is used for selecting an EV travel mode. Here, the shift operation device 81 is provided with the function as the EV traveling mode switching device.

The shift operation device 81 includes a shift lever 81a that is used when a driver performs a shift operation, a so-called shift gauge 81b that guides the shift lever 81a for each shift stage, the link mechanism, a fork, and the like. . For example, as the speed change operation device 81, the one shown in FIG. 2, 3 or 4 can be considered. “1 to 5” and “R” on the shift gauge 81b in each figure indicate the shift positions (select positions) of the first gear stage 31 to the fifth gear stage 35 and the reverse gear stage 39, respectively. Yes.

The

shift operation devices

81A and 81B shown in FIGS. 2, 3 and 4 are operated according to the position of the shift lever 81a by operating the shift lever 81a to the shift positions 1 to 5 and R when the clutch 50 is disengaged. The manual transmission 30 is switched to a different gear position.

The shift operation device 81A shown in FIGS. 2 and 3 is not only the shift positions 1 to 5 and R but also the select position of the shift lever 81a similar to this, and the EV travel mode selection for switching to the EV travel mode. A position EV is provided on the shift gauge 81b. In the hybrid vehicle 1 of the present embodiment, when the shift lever 81a is operated to the EV travel mode selection position EV as shown in FIG. 3, the travel mode becomes the EV travel mode. In this hybrid vehicle 1, when the shift lever 81a is operated to the EV travel mode selection position EV, the manual transmission 30 is in a neutral state by a sleeve or the like. Further, the shift operating device 81A also sets the manual transmission 30 to the neutral state when the shift lever 81a is operated to the neutral position shown in FIG.

On the other hand, the speed change operation device 81B shown in FIG. 4 does not include the EV travel mode selection position EV like the speed change operation device 81A. In this speed change operation device 81B, when the shift lever 81a is operated to the neutral position shown in FIG. 4, the manual transmission 30 is in the neutral state, and the travel mode is set to the EV travel mode.

This shift operation device 81 (81A, 81B) is provided with an EV travel mode selection position detector 82. The EV travel mode selection position detector 82 detects whether or not the EV travel mode is selected based on the position of the shift lever 81a on the shift gauge 81b. In the case of the speed change operation device 81A, for example, a position information detection sensor or the like that can detect that the shift lever 81a is at the EV travel mode selection position EV is used as the EV travel mode selection position detection unit 82. In the case of the speed change operation device 81B, for example, a position information detection sensor or the like that can detect that the shift lever 81a is in the neutral position is used as the EV travel mode selection position detection unit 82. The detection signal of the EV traveling mode selection position detection unit 82 is transmitted to an electronic control unit (hereinafter referred to as “hybrid ECU”) 100 that comprehensively controls the operation of the entire vehicle.

The hybrid ECU 100 can exchange information such as detection signals of various sensors and control commands between the engine ECU 101 and the motor / generator ECU 102. In this embodiment, at least the hybrid ECU 100, the engine ECU 101, and the motor / generator ECU 102 are constituent requirements of the vehicle control system.

The shift operation device 81 (81A, 81B) determines which shift position 1 to 5, R of the shift lever 81a is on the shift gauge 81b, that is, which shift stage the driver has selected. A shift position detecting unit 83 for detecting is provided. The shift position detector 83 may use, for example, a position information detection sensor that can detect which shift positions 1 to 5 and R the shift lever 81a is at. The detection signal is sent to the hybrid ECU 100. The hybrid ECU 100 determines the speed selected by the driver and the current speed based on the detection signal. Here, for the sake of convenience, the shift position detection unit 83 is illustrated as being different from the EV travel mode selection position detection unit 82, but these are replaced with a shift lever position detection unit (not shown) integrated into one. May be. Here, the hybrid ECU 100 may estimate the current shift speed from the engine torque, the wheel speed, or the like using a known technique known in this technical field.

When the shift lever 81a is operated to the shift positions 1 to 5 and R, the hybrid ECU 100 selects either the engine travel mode or the hybrid travel mode. For example, the hybrid ECU 100 includes a set driver's drive request (required driving force), information on the state of charge of the secondary battery 25 (SOC amount) sent from the motor / generator ECU 102, and information on the vehicle running state (illustrated). On the basis of the vehicle lateral acceleration detected by the vehicle lateral acceleration detection device and information on the slip state of the drive wheels WL and WR detected by the wheel slip detection device), the engine travel mode and the hybrid travel mode are switched. The hybrid ECU 100 sends a control command corresponding to the travel mode to the engine ECU 101 and the motor / generator ECU 102.

On the other hand, when the EV travel mode is selected based on the position of the shift lever 81a on the shift gauge 81b, the hybrid ECU 100 sends a control command corresponding to the travel mode to the engine ECU 101 and the motor / generator ECU 102.

In the hybrid vehicle 1, for example, the engine 10 is stopped during traveling in the EV traveling mode to improve fuel efficiency. Therefore, in the hybrid vehicle 1, it is necessary to start the engine 10 when switching from the EV travel mode to the engine travel mode using the engine torque or the hybrid travel mode. In this case, torque is transmitted to the engine 10 from the manual transmission 30 side, and the engine 10 is cranked with the torque to start. At that time, the driver operates the clutch pedal 51 and the shift operation device 81 so that the torque on the manual transmission 30 side is transmitted to the engine 10 via the clutch 50. In other words, at this time, after the clutch 50 is released, the shift lever 81a is operated to any one of the shift positions 1 to 5 and the clutch 50 is engaged, whereby the input of the manual transmission 30 is performed. A part of the torque on the output shaft 42 side is transmitted to the shaft 41, and the torque of the input shaft 41 is transmitted to the output shaft 11 of the engine 10. The torque on the output shaft 42 side is, for example, motor torque for generating driving force in the EV traveling mode.

Here, for example, when switching from the EV traveling mode to the engine traveling mode, a part of the motor torque for generating the driving force in the EV traveling mode is transmitted as cranking torque for starting the engine 10, thereby reducing the driving force. The accompanying deceleration may occur. At that time, the deceleration occurs with the generation of cranking torque (that is, with the start of engagement of the clutch 50). The cranking torque increases as the degree of engagement of the clutch 50 increases (that is, as the clutch 50 approaches the fully engaged state). On the other hand, as shown in FIG. 5, the engine speed starts to increase with a delay from the generation time of the cranking torque. The engine 10 in the stopped state is equal to or higher than the sum of the torque related to the maximum static friction of the engine 10 and the torque related to the compression pressure determined by the engine stop position or the like (hereinafter referred to as “rotation start cranking torque”). This is because it does not begin to rotate until. For this reason, the driver may feel uncomfortable that the deceleration occurs before the engine speed starts to increase. A driver who has not recognized the movement of the engine speed with a tachometer or the like expects the engine 10 to start as the engine speed increases by feeling the deceleration. However, if the engagement degree of the clutch 50 at this time (hereinafter referred to as “clutch engagement degree”) is smaller than the magnitude for generating the rotation start cranking torque, the driver temporarily engages the clutch 50 in this state. If the operation is stopped, the engine 10 cannot be started, and the transition to the engine running mode cannot be performed.

In this embodiment, when the engine 10 in a stopped state is started during traveling, a motor for generating a driving force using a motor torque corresponding to the torque capacity of the clutch 50 (hereinafter referred to as “clutch torque capacity”) as an assist torque. By outputting this added motor torque in addition to torque, the engine speed is increased by the assist torque.

The clutch torque capacity Tcl is, for example, as shown in Equation 1 below, the friction coefficient μ of the friction material of each

engagement portion

50a, 50b of the clutch 50, the total area A of the portions where the friction materials contact each other, respectively. The surface pressure P between the engaging

portions

50a and 50b and the outer diameter d of the portion where the friction materials come into contact with each other can be estimated.

Tcl = μ * A * P * d / 2 (1)

Here, the surface pressure P changes according to the amount of movement between the engaging

portions

50a and 50b of the clutch 50 and the pedal operation amount of the clutch pedal 51. On the other hand, the values other than the surface pressure P are design values and are invariable values. For this reason, it can be seen that the clutch torque capacity Tcl changes according to the surface pressure P, that is, the amount of movement between the engaging

portions

50a and 50b and the amount of pedal operation of the clutch pedal 51. That is, the clutch torque capacity Tcl increases as the half-engaged state of the clutch 50 approaches the fully engaged state, as shown in FIG.

In FIG. 6, the clutch torque capacity on the vertical axis can be replaced with the degree of clutch engagement. The degree of clutch engagement is estimated based on the amount of movement between the engaging

portions

50 a and 50 b or the pedal operation amount of the clutch pedal 51.

The hybrid ECU 100 can estimate the clutch torque capacity Tcl from the amount of movement between the engaging

portions

50a and 50b or the pedal operation amount of the clutch pedal 51. The amount of movement between the engaging

portions

50 a and 50 b can be obtained from the detection value of the so-called clutch stroke sensor 52. The pedal operation amount of the clutch pedal 51 can be obtained from a detection value of a so-called clutch pedal stroke sensor 53. Here, since the so-called play is provided in the clutch pedal 51, the clutch torque capacity Tcl is estimated by removing the pedal operation amount for the play (FIG. 6).

Since the driving force does not decrease due to the assist torque, the driver can start increasing the engine speed by engaging his own clutch without feeling uncomfortable deceleration. However, the output of the assist torque corresponding to the clutch torque capacity Tcl makes it difficult for the driver to feel the deceleration even after the engine speed starts to increase. This makes the driver feel uncomfortable this time.

Therefore, in this embodiment, when the stopped engine 10 is started during running, the motor torque corresponding to the clutch torque capacity Tcl is output as the assist torque Ta, and the clutch torque capacity Tcl is determined as the rotation start cranking torque Tcr. When the motor torque is increased to the maximum, the motor torque smaller than the clutch torque capacity Tcl is output as the assist torque Ta. That is, in this embodiment, when starting the engine 10 in a stopped state while traveling, the magnitude of the assist torque is controlled according to the clutch torque capacity Tcl.

Hereinafter, the calculation processing operation when starting the engine 10 in a stopped state while traveling will be described based on the flowchart of FIG. 7 and the time chart of FIG. Here, engine start when switching from the EV travel mode to the engine travel mode will be described.

When starting the engine, the hybrid ECU 100 determines whether or not the released clutch 50 has started engagement (step ST1). For example, a map as shown in FIG. 6 is prepared in advance, and this determination may be made based on this map and the pedal operation amount of the clutch pedal 51. Further, this determination may be made based on the detected movement amount between the engaging

portions

50a and 50b. Further, immediately after the engagement of the clutch 50 is started, the assist torque has not yet been output, and the deceleration is detected by the longitudinal acceleration sensor 91. Therefore, in step ST1, when the deceleration is detected, it may be determined that the clutch 50 starts to be engaged.

The hybrid ECU 100 repeats the determination in step ST1 until it is determined that the clutch 50 is not engaged unless the clutch 50 has started the engagement.

In contrast, when the hybrid ECU 100 determines that the clutch 50 has started to be engaged, the hybrid ECU 100 estimates the clutch torque capacity Tcl (step ST2), and the clutch torque capacity Tcl is determined from the rotation start cranking torque Tcr. Is also smaller (step ST3).

The rotation start cranking torque Tcr may be set to the sum of the torque related to the maximum static friction of the engine 10 and the maximum value of the torque related to the compression pressure. Further, the rotation start cranking torque Tcr may be set as follows. For example, when the engine 10 is stopped in a state where torque is applied, air in the cylinder disappears and the compression pressure decreases. Therefore, even if torque is applied to the output shaft 11, the output shaft 11 and piston ( (Not shown) does not start moving immediately. However, when the engine 10 continues to be applied while increasing the torque with respect to the output shaft 11, the output shaft 11 or the like starts to move. Therefore, the torque applied to the output shaft 11 when the output shaft 11 or the like starts moving may be set as the rotation start cranking torque Tcr.

Here, the clutch torque capacity Tcl increases with the start of engagement of the clutch 50 as shown in FIG. 8 while the half-engaged state continues. Therefore, if the clutch torque capacity Tcl is smaller than the rotation start cranking torque Tcr, the hybrid ECU 100 sets the motor torque corresponding to the clutch torque capacity Tcl as the assist torque Ta (step ST4), and uses the assist torque Ta as the motor. / The output is made to the generator 20 (step ST5).

At that time, the motor / generator 20 outputs the sum of the motor torque for generating the driving force in the EV traveling mode and the assist torque Ta. The assist torque Ta corresponding to the clutch torque capacity Tcl is updated as the clutch torque capacity Tcl increases, and continues to be output until the clutch torque capacity Tcl reaches the rotation start cranking torque Tcr. As a result, in the hybrid vehicle 1, during this period, the motor torque for generating the driving force is transmitted to the drive wheels WL and WR, while the assist torque Ta is transmitted to the engine 10 side. Therefore, in this hybrid vehicle 1, as shown in FIG. 8, the occurrence of deceleration due to a decrease in driving force is suppressed. That is, according to this control system, it is possible to suppress the occurrence of deceleration before the engine speed starts to increase as indicated by a one-dot chain line in FIG. Therefore, the driver does not feel a sense of incongruity until the clutch torque capacity Tcl reaches the rotation start cranking torque Tcr, even though the engine speed has not started increasing, but feels deceleration.

Here, the assist torque Ta set in step ST4 does not necessarily need to be completely matched with the motor torque corresponding to the clutch torque capacity Tcl. This is because whether it matches the motor torque depends on the estimation accuracy of the clutch torque capacity Tcl. Therefore, the magnitude of the assist torque Ta may be set within a range in which the driver does not experience deceleration.

On the other hand, when the hybrid ECU 100 determines in step ST3 that the clutch torque capacity Tcl is equal to or greater than the rotation start cranking torque Tcr, the hybrid ECU 100 sets a motor torque smaller than the clutch torque capacity Tcl as the assist torque Ta (step ST6). In step ST5, the assist torque Ta is output to the motor / generator 20.

The assist torque Ta at step ST6 is, for example, as shown by a solid line in FIGS. 8 and 9, regardless of the passage of time, the rotation start cranking torque Tcr, that is, the torque related to the maximum static friction of the engine 10 and the compression pressure. Is set to the sum of torques. In this case, the difference between the clutch torque capacity Tcl and the assist torque Ta increases with the passage of time, and a large deceleration can be generated with the passage of time.

Further, the assist torque Ta may be set such that the increase gradient is smaller than the increase gradient of the clutch torque capacity Tcl, as shown by a one-dot chain line in FIG. In this case, even if time elapses, the spread of the difference between the clutch torque capacity Tcl and the assist torque Ta can be suppressed as compared with the above example, so that the change in the deceleration is small and the engine 10 is completely started. Deceleration adjustment is easy.

Further, the assist torque Ta may be decreased with the passage of time as shown by a two-dot chain line in FIG. In this case, as compared with the above two examples, a large deceleration can be generated over time, and the power consumption of the secondary battery 25 required for the output of the assist torque Ta can be reduced. .

The assist torque Ta set in step ST6 is continuously output until the engine 10 has been started, as shown in FIG. For this reason, in the hybrid vehicle 1, deceleration occurs as the engine speed increases. That is, according to this control system, it is possible to avoid a situation in which deceleration does not occur even though the engine speed increases, as indicated by a two-dot chain line in FIG. Therefore, the driver does not feel uncomfortable until the engine 10 is started after the engine speed starts to increase.

Thus, the control system of the present embodiment does not give the driver the uncomfortable feeling when starting the engine 10 in a stopped state while traveling, and can start the engine reliably.

By the way, in a general vehicle in which a power source is an engine only and a manual transmission is mounted, a vehicle capable of coasting with the engine stopped when the shift lever is in the neutral position is known. In this vehicle, when the forward gear is selected by the driver's clutch operation and gear shift operation, the driving wheel side torque is transmitted to the engine side, and the engine is restarted. At this time, in this vehicle, the deceleration increases as the engine speed starts to increase. Any of the above settings may be applied to the assist torque Ta in step ST6, but it is preferable to set the assist torque Ta according to the degree of increase in deceleration at the time of engine start of the vehicle. Thereby, the hybrid vehicle 1 can give the driver a feeling of deceleration equivalent to that of the vehicle. Therefore, this control system can further eliminate the driver's uncomfortable feeling.

Further, the control system may be able to select the assist torque Ta of the above-described plural forms of step ST6 from among these in order to generate a deceleration without a sense of incongruity according to, for example, a road gradient. Further, this control system may be configured such that only one of the plural assist torques Ta in step ST6 is applied so that the same deceleration feeling can be always obtained.

Furthermore, this control system uses the clutch torque capacity Tcl for setting the assist torque Ta, but the assist torque Ta may be output without using the clutch torque capacity Tcl. In this case, since it is not necessary to obtain the clutch torque capacity Tcl, information on the amount of movement between the engaging

portions

50a and 50b or the pedal operation amount of the clutch pedal 51 becomes unnecessary, and the clutch stroke sensor 52 and the clutch pedal stroke sensor are eliminated. 53 need not be provided. Therefore, this control system can also reduce the cost accompanying the reduction in the number of parts.

For example, when the hybrid ECU 100 determines that the clutch 50 has started to be engaged, it monitors the vehicle longitudinal acceleration instead of the clutch torque capacity Tcl, and controls the motor while performing feedback control so that the fluctuation can be suppressed. Set the torque. The motor torque is the sum of the motor torque for generating the driving force and the assist torque Ta. The assist torque Ta may be increased with the rotation start cranking torque Tcr as an upper limit value. As a result, during the period until the assist torque Ta reaches the rotation start cranking torque Tcr, the occurrence of deceleration is suppressed by suppressing fluctuations in the longitudinal acceleration of the vehicle. This eliminates the driver's uncomfortable feeling. In addition, after the start of the engine speed increase, the assist torque Ta can be suppressed with the rotation start cranking torque Tcr as the upper limit, so that a deceleration can be generated as the engine speed increases, eliminating the driver's uncomfortable feeling. it can.

In the above example, as shown in FIG. 7, the characteristic of the assist torque Ta to be set is changed based on the comparison result between the clutch torque capacity Tcl and the rotation start cranking torque Tcr. Instead of the comparison, the control system monitors the engine speed Ne based on the detection signal of the crank angle sensor 12, and determines whether the engine 10 is rotating or makes the driver feel a deceleration. The assist torque Ta characteristic may be changed based on whether or not it is.

At that time, as shown in the flowchart of FIG. 10, the hybrid ECU 100 determines whether or not the released clutch 50 has started engagement (step ST11), and if the clutch 50 has not started engagement. Until it is determined that the engagement is started, the determination in step ST1 is repeated. If it is determined that the clutch 50 has started engagement, the clutch torque capacity Tcl or the clutch engagement degree is estimated (step ST12). . The hybrid ECU 100 determines whether or not the engine 10 is rotating (Ne> 0?) Or whether the engine speed Ne exceeds a predetermined rotation number α (Ne> α?) ( Step ST13). The predetermined rotational speed α is set based on whether or not the engine rotational speed Ne is a magnitude that allows the driver to experience deceleration. Here, the upper limit value of the engine speed Ne at which the deceleration is not felt is set to the predetermined speed α.

When the hybrid ECU 100 determines that the engine 10 is not rotating or the engine rotational speed Ne does not exceed the predetermined rotational speed α, the hybrid ECU 100 sets the assist torque Ta according to the estimated clutch torque capacity Tcl or the clutch engagement degree ( In step ST14, the assist torque Ta is output to the motor / generator 20 (step ST15). The setting and output of the assist torque Ta are repeated until the engine 10 starts to rotate or until the engine speed Ne exceeds the predetermined speed α.

The assist torque Ta is a motor torque corresponding to the clutch torque capacity Tcl as in the previous example. Therefore, if what is estimated in step ST12 is the clutch engagement degree, the clutch torque capacity Tcl corresponding to the clutch engagement degree is obtained, and the motor torque corresponding to the clutch torque capacity Tcl is set as the assist torque Ta. In this case, a map of assist torque Ta (= Tcl) corresponding to the degree of clutch engagement may be prepared in advance, and assist torque Ta may be set based on the degree of clutch engagement and the map. As a result, the driver feels uncomfortable that he / she feels deceleration even though the engine speed has not started increasing until the engine 10 starts to rotate or until the engine speed Ne exceeds the predetermined speed α. Absent.

On the other hand, when the hybrid ECU 100 determines that the engine 10 is rotating or the engine speed Ne exceeds the predetermined speed α, the hybrid ECU 100 obtains a motor torque corresponding to the clutch torque capacity Tcl when this determination is first performed. The assist torque Ta is set (step ST16), the process proceeds to step ST15, and the assist torque Ta is output to the motor / generator 20. That is, when it is determined that the engine 10 is rotating, the motor torque corresponding to the clutch torque capacity Tcl when the engine 10 starts rotating is set as the assist torque Ta. When it is determined that the engine speed Ne exceeds the predetermined speed α, the motor torque corresponding to the clutch torque capacity Tcl when the engine speed Ne exceeds the predetermined speed α is set as the assist torque Ta. Set. The assist torque Ta set in step ST16 is continuously output until the engine 10 has been started. For this reason, in the hybrid vehicle 1, deceleration occurs as the engine speed increases. Therefore, the driver does not feel uncomfortable until the engine 10 is started after the engine speed starts to increase.

Here, in the embodiment described above, the motor / generator 20 is connected to the output shaft 42 via the gear pair 60, but the control system of this embodiment directly connects the motor / generator 20 to the output shaft 42. The present invention may be applied to a hybrid vehicle or a hybrid vehicle in which the motor / generator 20 is connected to the input shaft 41, and the same effects as those described above can be obtained.

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 10 Engine 11 Output shaft 20 Motor / generator 30 Manual transmission 41 Input shaft 42 Output shaft 50 Clutch 50a, 50b Engagement part 51 Clutch pedal 52 Clutch stroke sensor 53 Clutch

pedal stroke sensor

81, 81A, 81B

81a Shift lever

81b Shift gauge 100 Hybrid ECU
101 engine ECU
102 Motor / generator ECU
EV travel mode selection position WL, WR Drive wheel

Claims

A mechanical power source powered by mechanical energy;
An electrical power source powered by mechanical energy converted from electrical energy;
A torque transmission device capable of transmitting torque between the mechanical power source and the electric power source and drive wheels;
A first operating device for the driver to manually change the torque transmission form of the torque transmitting device;
A torque connecting / disconnecting device capable of connecting / disconnecting torque transmission between the mechanical power source and the electric power source and between the mechanical power source and the drive wheel;
A second operating device when a driver manually operates the connecting / disconnecting operation of the torque connecting / disconnecting device;
With
By operating the first operating device and the second operating device during traveling, torque is transmitted to the mechanical power source in accordance with the engagement operation of the torque connecting / disconnecting device, and the stopped mechanical power source is started. When the torque power of the torque connecting / disconnecting device is increased to the rotation start cranking torque of the mechanical power source, the assist torque having a magnitude that does not cause the driver to experience deceleration is output to the electric power source. A vehicle control system that outputs an assist torque smaller than a capacity to the electric power source.
2. The vehicle control system according to claim 1, wherein the assist torque when the torque capacity is smaller than the rotation start cranking torque is set to a magnitude corresponding to the torque capacity.