JP6942558B2 - Hybrid vehicle control method - Google Patents

Description

The present invention relates to a method for controlling a hybrid vehicle in which a traveling mode can be switched via a clutch engagement / disengagement operation provided between a power source and a transmission.

Conventionally, a power source consisting of an engine and a motor, a transmission in which a driving force can be transmitted via an intermittent clutch between the power source, and a transmission, which is arranged between the transmission and wheels. A hybrid vehicle having a differential mechanism and a control means for outputting a rotation speed and a torque command signal to an engine and a motor and controlling a clutch engagement state is known.
This hybrid vehicle is configured to be able to switch between an electric traveling mode in which the vehicle travels by the power of a motor and a hybrid traveling mode in which the vehicle travels by the power of an engine and a motor.

Further, in such a hybrid vehicle, a course in which the engine is stopped and the clutch is released in the case of steady driving or slow deceleration driving in which the accelerator pedal is depressed and the vehicle speed is lower than the predetermined vehicle speed, so-called acceleration request by the driver is not required. Ting running (coasting running) is being performed.
In this coasting run, since the power source (engine) is physically separated from the wheels, it is possible to avoid energy loss due to dragging of the engine and improve fuel efficiency without having to rotate the engine in a stopped state. ..

On the other hand, when the driving torque of the vehicle is switched from negative to positive by the driver's depression of the accelerator pedal during coasting, the differential gear, final gear, etc., which are the operating parts of the power transmission system, are caused by the clutch engagement operation. There is a risk that a shock will occur when the clutch is engaged due to the gear rattling phenomenon caused by the backlash (play).
The drive torque control device for a hybrid vehicle of Patent Document 1 is used to switch the drive torque of a vehicle from negative to positive by the driver's depression of the accelerator pedal, and during the drive state switching determined by the gear backlash determination means, the engine torque. Is maintained at a constant backlash torque, and the motor torque value is increased and corrected so as to complement the difference between the target engine torque and the required torque of the engine.

Japanese Patent No. 5360032

When engaging the clutch according to the driver's acceleration request, it is necessary to converge the engine (side clutch plate) rotation speed and the input shaft (side clutch plate) rotation speed in order to make the engine torque and the clutch engagement force substantially match. be.
Further, the fastening force of the clutch is proportional to the friction coefficient of the friction material, and the friction coefficient is proportional to the temperature.
The temperature of the friction material of the clutch is unstable due to the usage environment, etc., and in particular, the temperature change of the dry multi-plate clutch is more remarkable than that of the wet multi-plate clutch, so it is easy to adjust the friction coefficient of the friction material. is not it.

Based on the above, by prolonging the half-clutch state, the engine speed and the input shaft speed can be converged to the same speed without the need to adjust the friction coefficient of the friction material, and the fastening shock can be achieved. It enables less smooth clutch engagement operation.
However, if there is a long-term half-clutch period in addition to the engine restart (cranking) period after the driver depresses the accelerator pedal, there is a time between the driver's request for acceleration and the time when the vehicle accelerates. There is a perceptible time difference, which may cause the driver to feel uncomfortable.
That is, the improvement of the operation responsiveness of the vehicle and the reduction of the shock associated with the clutch engagement form conflicting demands.

During the coasting run, the state in which the wheel side gear corresponding to the driving side operating portion comes into contact with the transmission side gear corresponding to the driven side operating portion and the transmission side gear is driven is the deceleration contact state, and the acceleration running. In the middle, the state in which the transmission-side gear corresponding to the driving-side operating portion comes into contact with the wheel-side gear corresponding to the driven-side operating portion to drive the wheel-side gear is the acceleration contact state. Then, in each gear, the relative angle difference from the deceleration contact state to the acceleration contact state can be regarded as backlash (play) related to the state displacement.
In the technique of Patent Document 1, during the drive state switching, in other words, during the displacement period from the deceleration contact state to the acceleration contact state, the gear backlash packing torque smaller than the required torque is held as the output torque of the engine. The gear backlash packing period (displacement period from the deceleration contact state to the acceleration contact state) is shortened while improving the accuracy of the gear backlash packing torque.

However, in the technique of Patent Document 1, when the rattling control is performed, if the resonance component of the drive shaft included in the rattling torque of the motor is large, a shock due to the resonance of the drive shaft may occur.
Further, during coasting driving, when the clutch is engaged after restarting the engine in response to the driver's acceleration request, the initial explosion torque of the engine is amplified by the torque converter and transmitted to the wheels, so that the driver There is also a risk of shock perceived by the engine.
That is, Patent Document 1 leaves room for drastic improvement in reducing the shock associated with clutch engagement.

An object of the present invention is to provide a control method for a hybrid vehicle that can achieve both improvement in operational responsiveness of the vehicle and reduction of shock associated with clutch engagement.

The method for controlling a hybrid vehicle according to claim 1 is a power source including an engine and a motor, a transmission connected to the power source so as to transmit a driving force via an intermittent clutch, and the transmission. A differential mechanism including a driving side operating portion and a driven side operating portion driven by the driving side operating portion between the wheels, and the engine and the motor are output with rotation speed and torque command signals, respectively, and the clutch is engaged. In the control method of a hybrid vehicle provided with a control means for controlling the state, when the vehicle shifts from the deceleration state to the acceleration state, the deceleration contact state between the driving side operating portion and the driven side operating portion is used for acceleration. After the preparatory step of setting the amount of movement for displacement to the contact state as a relative angle difference and the period after the clutch is engaged and the period of transition from the deceleration contact state to the acceleration contact state elapses, the driving side operating portion and the driven side It is characterized by having an angular velocity converging step that controls the motor so as to converge the relative angular velocity with the operating portion.

In this hybrid vehicle control method, when the vehicle shifts from the deceleration state to the acceleration state, the amount of movement for shifting from the deceleration contact state to the acceleration contact state between the driving side operating portion and the driven side operating portion. Since there is a preparatory step to set the relative angle difference, the existing backlash formed between the driving side operating portion and the driven side operating portion can be used as the relative angle difference.
After the clutch is engaged, after a period of transition from the deceleration contact state to the acceleration contact state elapses , the angular velocity convergence step that controls the motor so as to converge the relative angular velocity between the driving side operating portion and the driven side operating portion is performed. a, it is possible to converge the engine side clutch plate speed and the input shaft side clutch plate rotational speed between the period of transition from the decelerating contact with the accelerating contact.
Moreover, by converging in the period to migrate relative angular velocity between the driving-side operating portion and the driven-side operating portion to accelerating the contact state from the decelerating contact state, when the driving-side operating portion and the driven-side operating portion collides The relative angular velocity can be minimized, and the clutch engagement can be accelerated without causing a shock due to a collision between the driving side operating portion and the driven side operating portion.

The invention of claim 2 is the invention of claim 1, wherein when the driver releases the acceleration operation, the coasting step of stopping the engine and releasing the clutch and the acceleration operation by the driver are performed. When executed, it is characterized by having a clutch engagement step for engaging the clutch after starting the engine.
According to this configuration, it is possible to improve the operability of the vehicle and reduce the shock caused by the clutch engagement while improving the fuel efficiency by coasting.

According to the invention of claim 1, in the invention of claim 1 or 2, in the angular velocity convergence step, the motor is opened-looped according to a preset relative angle difference map between the driving side operating portion and the driven side operating portion. It is characterized by controlling.
According to this configuration, the motor can be controlled based on a preset relative angle difference between the driving side operating portion and the driven side operating portion without requiring actual motion detection.

In the invention of any one of claims 1 to 3, the invention of claim 4 temporarily controls the clutch in the engaging direction and sets the initial state of the relative angle difference before the angular velocity convergence step. It is characterized by having an initial state setting step to be performed.
According to this configuration, the initial state of the driving side operating portion and the driven side operating portion can be easily set to the deceleration contact state.

The invention of claim 5 has, in the invention of any one of claims 1 to 4, a vibration damping control step in which the motor is feedback-controlled by adding the torsional torque of the drive shaft after the angular velocity convergence step. It is characterized by.
According to this configuration, the vehicle can be accelerated without vibration by feedback control in which the torsional torque of the drive shaft is added.

According to the control method of the hybrid vehicle of the present invention, the operation responsiveness of the vehicle is improved and the shock associated with the clutch engagement is reduced by utilizing the relative angle difference for displacing from the deceleration contact state to the acceleration contact state. be able to.

It is a figure which shows the powertrain model of the hybrid vehicle which concerns on Example 1. FIG. It is explanatory drawing of the contact state for deceleration and the enlarged view of the main part thereof. It is explanatory drawing of the transient state and the enlarged view of the main part thereof. It is explanatory drawing of the contact state for acceleration and the enlarged view of the main part thereof. It is a control block diagram which shows the control system of a power train. It is a functional block diagram in the angular velocity convergence step. It is a functional block diagram which shows the power plant command value calculation mechanism. Relative angle difference map, relative angular velocity characteristics and angular acceleration characteristics. It is a flowchart which shows the control processing procedure. It is a time chart of each element which concerns on Example 1. FIG. Relative angle difference map, relative angular velocity characteristics, and angular acceleration characteristics related to the modified example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The following description illustrates an application of the present invention to a control system for a hybrid vehicle, and does not limit the present invention, its application, or its use.

Hereinafter, Example 1 of the present invention will be described with reference to FIGS. 1 to 10.
First, the outline of the power train PT of the hybrid vehicle according to the first embodiment will be described.
As shown in FIG. 1, the power train PT of this hybrid vehicle has an in-line 4-cylinder reciprocating engine 1 as a first power source and a motor generator as a second power source arranged downstream of the engine 1. Hereinafter, it is abbreviated as a motor.) 2, an automatic transmission (hereinafter, abbreviated as AT) 3 arranged at a position on the downstream side of the motor 2, and a driving force is distributed to a pair of left and right wheels 5. It is equipped with a differential gear mechanism (hereinafter abbreviated as a differential mechanism) 4 and the like.

The output shaft of the engine 1 and the rotating shaft of the motor 2 are coaxially connected by a shaft 6 via an intermittent first clutch 11.
The first clutch 11 is composed of a dry multi-plate clutch capable of continuously or stepwise controlling the clutch hydraulic oil flow rate and the clutch hydraulic pressure by a motor (not shown) to change the transmission torque capacity. The upstream end of the first clutch 11 is connected to the output shaft of the engine 1 via the shaft 6a, and the downstream end of the first clutch 11 is connected to the rotary shaft of the motor 2 via the shaft 6b. It is connected to the upstream end.

The rotating shaft of the motor 2 and the rotating shaft of the AT3 are coaxially connected by a shaft 7 via an intermittent second clutch 12 (clutch).
Like the first clutch 11, the second clutch 12 is composed of a dry multi-plate clutch capable of continuously or stepwise controlling the clutch hydraulic oil flow rate and the clutch hydraulic pressure by a motor to change the transmission torque capacity. .. The upstream end of the second clutch 12 is connected to the downstream end of the rotating shaft of the motor 2 via the shaft 7a, and the downstream end of the second clutch 12 is connected to the downstream end of the rotating shaft of the motor 2 via the shaft 7b. It is connected to the rotating shaft of. An upstream flywheel having a predetermined weight is provided on the shaft portion 7a, and a downstream flywheel is provided on the shaft portion 7b (both are not shown).
The second clutch 12 may be formed inside the AT3 as long as the transmission of the driving force between the motor 2 and the AT3 can be interrupted.

As shown in FIG. 1, in the differential mechanism 4, a driving force is input via the output shaft 8 of the AT3, and the driving force is applied to the drive shaft 9 (drive shaft) corresponding to the left and right wheels 5 according to the steering state. The distribution rate can be changed.
The shaft 6, the shaft 7, the output shaft 8, and the drive shaft 9 are all formed so as to be twistably deformable, and in particular, the drive shaft 9 has a characteristic that can be modeled by using a spring mass model.

As shown in FIG. 2, the differential mechanism 4 includes a plurality of power transmission operating portions 13 and a shaft 14 including a differential gear, a final gear, a pinion, and the like.
The plurality of power transmission operating portions 13 and shafts 14 are derived from a driving side operating portion 13 that drives adjacent operating portions via meshing of the respective gears and the driving side operating portion 11 according to the traveling state of the vehicle. These functions are switchable to the driven side operating unit 14 driven via the meshing of the respective gears.

Specifically, during deceleration or coasting, the rotational speed of the wheels 5 (angular velocity of the drive shaft 9) is faster than the angular velocity of the power source, for example, the motor 2, so that the operating portion on the downstream side (wheel 5 side) Functions as the driven side operating unit 13, and the upstream (AT3 side) operating unit driven from the driven side operating unit 13 functions as the driven side operating unit 14.
It should be noted that even the driven side operating portion 14 driven by the operating portion on the downstream side fulfills the function of the driving side operating portion 13 that transmits the driving force to the operating portion on the upstream side of the operating portion. ..
On the other hand, as shown in FIG. 4, since the angular velocity of the power source is faster than the rotation speed of the wheels 5 during acceleration, the upstream operating portion functions as the driving side operating portion 13, and the driving portion 13 The driven downstream actuating portion functions as the driven side actuating portion 14.
Hereinafter, the state in which the operating portion located on the most downstream side is the driving side operating portion 13 and the operating portion located on the most upstream side is the driven side operating portion 14, that is, the power from the most downstream operating portion is the most upstream side. The state of smooth transmission to the operating unit (Fig. 2) is defined as the deceleration contact state, and the operating unit located on the most upstream side is the driving side operating unit 11 and the operating unit located on the most downstream side is the driven side operating unit. The state of the unit 14 (FIG. 4) is defined as the acceleration contact state.

Further, a predetermined gap (also referred to as backlash or backlash) is formed between the driving side operating portion 13 and the driven side operating portion 14, respectively.
As shown in FIG. 3, immediately after the operating state of the vehicle is operated from deceleration running to acceleration running, the function of the most upstream operating unit is changed from the function of the driven side operating unit 14 to the function of the driving side operating unit 13. On the way, in other words, with the displacement operation, the gear of the most upstream operating portion becomes a transient state separated from the gears of the adjacent operating portions by a predetermined distance.
Then, in the structure as a whole, the power of the most downstream operating portion is transmitted to the plurality of power transmission operating portions 13 and 14 from the deceleration contact state in which the power of the most downstream operating portion is transmitted to the most downstream operating portion. A relative angle difference Δθ is formed for displacementing over the acceleration contact state transmitted to the side actuating portion. The relative angle difference Δθ of this embodiment is set in advance to, for example, about 4 °.
The relative angle difference Δθ for displacing from the acceleration contact state to the deceleration contact state is the same as the relative angle difference Δθ for displacing from the deceleration contact state to the acceleration contact state. ..

In the power train PT of this hybrid vehicle, when an electric driving mode (hereinafter referred to as EV mode) executed during low load / low speed operation is required, the first clutch 11 is released and the second clutch 12 is engaged. Will be done.
When the motor 2 is driven in this state, the rotational output of the motor 2 is transmitted to the AT3 side. The AT3 shifts the transmitted rotation output to the selected shift stage and outputs it from the output shaft 8 of the AT3. The driving force from the output shaft 8 of the AT3 reaches the left and right wheels 5 via the differential mechanism 4, and the traveling in the EV mode is executed.
When a hybrid driving mode (hereinafter referred to as HEV mode) executed during high-load / high-speed operation is required, the first and second clutches 11 and 12 are engaged together.
In this state, both the rotational output of the engine 1 or the rotational output of the engine 1 and the rotational output of the motor 2 are transmitted to the AT3 side. The AT3 shifts the transmitted rotation output to the selected shift stage and outputs it from the output shaft 8 of the AT3. The driving force from the output shaft 8 reaches the left and right wheels 5 via the differential mechanism 4 and the drive shaft 9, and the traveling in the HEV mode is executed.
The driving mode switching timing of the EV mode and the HEV mode is determined based on a map in which the vehicle speed and the load are set as parameters in advance.

Further, in the power train PT, when the driver performs an acceleration release operation, that is, a so-called driver's step-back operation, the engine 1 is stopped by the fuel cut control and the first and second clutches 11 and 12 are released. Running (coasting) is executed.
As a result, the engine 1 is in a stopped state, and the state of the operating portion of the differential mechanism 4 is a deceleration contact state in which the power of the most downstream operating portion is transmitted to the most upstream side operating portion.
As a result, the stopped engine 1 is physically separated from the wheels 5, so that energy loss due to dragging of the engine 1 is avoided and fuel efficiency is improved.

Next, the VCM 20 will be described.
The following description includes a description of the control method of the hybrid vehicle.
As shown in FIG. 5, this power train PT is integratedly controlled by a VCM (Vehicle Control Module) 20 (control means) as an integrated controller.
The VCM 20 responds to the target rotation speed and target torque of the motor 2 with respect to the PCM 21 that outputs a command signal of the target rotation speed and the target torque to the engine 1 and the inverter 15 that controls the amount of electricity supplied to the motor 2. It is electrically connected to the TMCM 22 that outputs a command signal and the TCM 23 that outputs an operation command signal to the motors of the first and second clutches 11 and 12, and periodically outputs a control command to these control modules. doing.

As shown in FIG. 5, the VCM 20 includes an engine rotation speed sensor 31, a motor rotation speed sensor 32, a motor torque sensor 33, a speed sensor 34 for detecting the traveling speed of a vehicle, and depression of an accelerator pedal (not shown). It is electrically connected to an accelerator sensor 35 that detects the amount, a storage sensor 36 that detects the storage state of the battery 16 that supplies electricity to the inverter 15, a brake sensor (not shown), and the like, and periodically from these sensors. Each detection signal is input.
As a result, the VCM 20 has the target rotation speed and the target torque of the engine 1 with respect to the PCM 21 so as to realize the running state (driving state) required by the driver according to the detected throttle valve opening degree, vehicle speed, and the like. Is commanded, and the target rotation speed and target torque of AT2 are commanded to TMCM22.

Further, the VCM 20 has an initial state setting function, an engine speed increase function, a second clutch engagement function, and an angular velocity convergence function executed when shifting from coasting running or slow deceleration running to accelerated running. It has a vibration control function.
When the accelerator sensor 35 detects the on-operation during coasting, the so-called driver detects the accelerator pedal depression operation, the driver detects the acceleration request, and at the same time, the first clutch 11 is engaged and the engine 1 is restarted. Is running.

First, the initial state setting function will be described.
In the initial state setting step related to the initial state setting function, a plurality of power transmission operating units 13 and 14 are initially controlled by temporarily and instantaneously controlling the second clutch 12 in the engaging direction before executing the angular velocity convergence step. It is set to the deceleration contact state as the state. As a result, the plurality of power transmission operating units 13 and 14 can be accurately initially set to a constant state at any time.
The execution condition of this initial state setting step is that the rotation speed N _IS of the shaft 7 is higher than the rotation speed N _{e of the engine 1.}

Next, the engine speed increasing function will be described.
In the engine rotation speed increasing step related to the engine rotation speed increasing function, the rotation speed N _e of the engine 1 is the sum _{of the rotation speed N IS} of the shaft portion 7a and the _{predetermined rotation speed difference N d} created before and after the clutch before the clutch is engaged. The engine 1 is driven with the maximum torque until it exceeds. The difference between the rotational speed N _DS rotational speed N _IS and the shaft portion 7b of the sum exceeds and shaft portion 7a of the speed N _e of the engine 1 and the rotational speed N _m of the rotational speed N _IS and the motor 2 of the shaft portion 7a When exceeds a predetermined first determination value, the second clutch engagement function is executed. The second clutch 12 is engaged at the maximum capacity of the motor without going through a half-clutch period, which is a sliding operation for matching the rotation speeds of the upstream clutch plate and the downstream clutch plate.

_{The rotation speed N DS} of the shaft portion 7b increased, and the difference between the rotation speed N _IS of the shaft portion 7a and the rotation speed N _DS of the shaft portion 7b became less than the predetermined second judgment value (<first judgment value). When the angular velocity convergence step is performed.
In the angular velocity convergence step, when shifting from coasting running or slow deceleration running to acceleration running, the relative angular velocity between the driving side operating unit 13 and the driven side operating unit 14 within the period of transition from the deceleration contact state to the acceleration contact state. The motor 2 is controlled so as to converge ω.

As shown in FIG. 6, the angular velocity convergence step can be represented by a functional block diagram including a power plant command value calculation mechanism P, a power plant model M, a disturbance observer R, and the like.
The power plant model M is a controlled object model in which the wheels 5 and the drive shaft 9 are removed from the power plant PT such as the engine 1, the motor 2, the AT3, and the differential mechanism 4.
The disturbance observer R is an observer mechanism capable of estimating the estimated engine torque eTe, the estimated angular velocity eω _IS of the shaft portion 7a, the estimated shaft twist angle θ _{DS of} the shaft portion 7b, and the like based on predetermined observed values.

As shown in FIG. 7, the power plant command value calculation mechanism P has an open loop system control including a target relative angular velocity difference setting means P1, a target relative angular velocity setting means P2, and a target torque setting means P3, and an engine angular velocity (rotation speed). ) State feedback that calculates the estimated relative angular velocity (transition speed from the deceleration contact state to the acceleration contact state) between the driving side operating unit 13 and the driven side operating unit 14 based on Ne and the estimated angular velocity eω _{IS of the shaft portion 7a.} It is composed of system control, and finally _{the sum of the engine target torque T e} ^* and the motor target torque T _m ^* is calculated.

As shown in FIG. 8A, the target relative angle difference setting means P1 stores the relative angle difference profile in advance as a control characteristic map.
This relative angle difference profile is set so as to rise sharply from the origin which is the lower limit on the deceleration side and gradually converge with respect to the upper limit on the acceleration side in the period T1.
The relative angle difference Δθ between the lower limit on the deceleration side and the upper limit on the acceleration side is a preset 4 °.

The target relative angular velocity setting means P2 calculates the target relative angular velocity by differentiating the relative angular velocity difference profile in FIG. 8 (a) (FIG. 8 (b)), and the target torque setting means P3 differentiates the target relative angular velocity. By doing so, the angular acceleration is calculated (FIG. 8 (c)).
As a result, in the transition period from the deceleration contact state (see FIG. 2) to the acceleration contact state (see FIG. 3), that is, in the period T1, the relative when the driving side operating portion 13 and the driven side operating portion 14 collide with each other. The angular velocity ω can be minimized, and the second clutch 12 is engaged early without causing a shock due to the collision between the driving side operating portion 13 and the driven side operating portion 14.

Next, the vibration damping control function will be described.
The vibration damping control step related to the vibration damping control function accelerates the vehicle while suppressing vibrations generated in the shaft portion 7a and the drive shaft 9.
This damping control step, the estimation of the estimated axis twist angle E.theta _DS and the drive shaft 9 of the shaft portion 7b twisted using a disturbance observer R of the rotational speed N _e of the torque T _m and the engine 1 of the motor 2 and the observation point The torque T _S is estimated, and the control commands for the engine 1 and the motor 2 are set in consideration of these estimated shaft torsional reaction force torques eT _DS and eT _s.

Next, the control processing procedure of the VCM 20 will be described based on the flowchart of FIG. 9 and the time chart of FIG.
In addition, Si (i = 1, 2, ...) Indicates a step for each process.
Further, the time chart of FIG. 10, respectively in order from the first stage, the accelerator depression operation, control phase, clutch engaging torque, the engine speed N _e, the relative angle difference Δθ of the driving-side operating portion 13 and the driven-side operation portion 14 s Shown.

As shown in the flowchart of FIG. 9, first, in S1, the detected values of the sensors 31 to 36 and information such as various maps are read, and the process proceeds to S2.
In S2, it is determined whether or not there is an acceleration request by the driver during the coasting run.
As a result of the determination in S2, when there is an acceleration request by the driver during coasting running (time point t0), the engine 1 is stopped, so the engine 1 is restarted and the first phase is started (S3).
In S3, after the first clutch 11 is engaged with the maximum torque, the engine 1 is cranked using the motor 2.
As a result of the determination in S2, if there is no acceleration request by the driver during the coasting run, the vehicle returns.

In S4, the initial state setting control (initial state setting step), which is the second phase, is executed.
At the time point t1 in FIG. 10, the plurality of power transmission operating units 13 and 14 are set to the deceleration contact state by temporarily and instantaneously controlling the disengaged second clutch 12 in the engaging direction.
After S4 initial state setting step, increases the speed N _e of the engine 1 (S5), the process proceeds to S6.

In S6, it is determined whether or not the engine speed N _e exceeds the sum of the motor speed N _m and the rotation speed N _{IS of the shaft portion 7a.}
As a result of the determination in S6, when the engine speed N _e exceeds the sum of the motor speed N _m and the rotation speed N _IS of the shaft portion 7a, the process shifts to S7, and the rotation around the second clutch 12 is suppressed while suppressing vibration. to match the number and executes the engine speed N _e state feedback speed control (the engine rotational speed setting step).
As a result of the determination in S6, if the engine speed N _e is equal to or less than the sum of the motor speed N _m and the rotation speed N _IS of the shaft portion 7a, the engine returns to S5 and the engine 1 speed N _e continues to increase.

In S8, it is determined whether or not the engine rotation speed N _e matches the sum of the rotation speed N _{IS of the shaft portion 7a and a predetermined rotation speed difference N d} created before and after the clutch before the clutch is engaged.
As a result of the determination in S8, when the engine speed N _e matches the sum of the motor speed N _m and the speed N _IS of the shaft portion 7a (time point t2), the process shifts to S9 and the second clutch 12 is set to the maximum torque. Fasten operation.
Since there is a relative angle difference between the driving side operating portion 13 and the driven side operating portion 14, the clutch engagement shock is suppressed even if the second clutch 12 is engaged without going through the half-clutch state.
As a result of the determination in S8, if the engine speed N _e does not match the sum of the motor speed N _m and the speed N _IS of the shaft portion 7a, the engine speed returns to S7 and the engine speed setting step is continued.

In S10, the start angular velocity convergence control (angular velocity convergence step), which is the third phase, is executed.
The relative angular velocity between the driving side operating unit 13 and the driven side operating unit 14 is calculated based on a preset relative angle difference profile within the period during which the transmission operating units 13 and 14 shift from the deceleration contact state to the acceleration contact state. And converged. This reduces the shock caused by the gear tooth striking phenomenon that accompanies the engagement of the clutch.

In S11, it is determined whether or not the transmission operating units 13 and 14 have completed the transition from the deceleration contact state to the acceleration contact state.
As a result of the determination in S11, when the transmission operating units 13 and 14 complete the transition from the deceleration contact state to the acceleration contact state (time point t3), the transition to S12 is performed and the torsional torque control, which is the fourth phase, is executed.
As a result of the determination in S11, if the transmission operating units 13 and 14 have not completed the transition from the deceleration contact state to the acceleration contact state, they return to S10 and continue the angular velocity convergence step.

Next, in S13, it is determined whether or not the acceleration request by the driver has been completed.
As a result of the determination in S13, when the acceleration request by the driver is completed, the torsional torque control is terminated (S14) and the engine returns.
As a result of the determination in S13, if the acceleration request by the driver has not been completed, the engine returns to S12 and the torsional torque control is continued.
As shown in the relative angle difference Δθ (backlash) in FIG. 10, the transmission operating portions 13 and 14 move from the time point t2 to the time point t3 and quickly and smoothly shift from the deceleration contact state to the acceleration contact state, so that the state displacement occurs. The occurrence of the accompanying shock is suppressed.

Next, the operation and effect of the control method of the hybrid vehicle will be described.
In this hybrid vehicle control method, when the vehicle shifts from the deceleration state to the acceleration state, the relative between the driving side operating unit 13 and the driven side operating unit 14 is displaced from the deceleration contact state to the acceleration contact state. Since the preparatory step for forming the angle difference is provided, the existing backlash formed between the driving side operating portion 13 and the driven side operating portion 14 can be used as the relative angle difference. After the second clutch 12 is engaged, after a period of transition from the deceleration contact state to the acceleration contact state elapses , the angular velocity convergence that controls the motor 2 so as to converge the relative angular velocity between the driving side operating portion 13 and the driven side operating portion 14. because having a step, period at the engine side clutch plate rotational speed of the second clutch 12 (the shaft portion 7a rpm) and aT clutch plates rotational speed of the second clutch 12 to shift to accelerating the contact state from the decelerating contact (Shaft portion 7b rotation speed) can be converged.
Moreover, by converging in the period of transition to the accelerating contact from decelerating contact state relative angular velocity between the driving-side operating portion 13 and the driven-side operating portion 14, the driving-side operating portion 13 and the driven-side operation portion 14 The relative angular velocity at the time of collision can be minimized, and the clutch engagement can be accelerated without causing a shock due to the collision between the driving side operating portion 13 and the driven side operating portion 14.

When the driver releases the acceleration operation, the engine 1 is stopped and the first and second clutches 11 and 12 are released, and when the driver executes the acceleration operation, the engine 1 Since it has a clutch engagement step for engaging the second clutch 12 after starting the engine, it is possible to improve the responsiveness of the vehicle operation and reduce the shock caused by the clutch engagement while improving the fuel efficiency by coasting. can.

In the angular velocity convergence step, the motor 2 is open-loop controlled according to the relative angle difference map between the driven side operating unit 13 and the driven side operating unit 14 set in advance, so that the actual operation detection is not required in advance. The motor 2 can be controlled based on the relative angle difference between the driven driving side operating unit 13 and the driven side operating unit 14 that has been set.

Prior to the angular velocity convergence step, there is an initial state setting step in which the second clutch 12 is temporarily controlled in the engaging direction to set the initial state of the relative angle difference. Can be easily set to the deceleration contact state as the initial state.

After the angular velocity convergence step, there is a vibration damping control step that feedback-controls the motor 2 by adding the torsional torque of the drive shaft 9. Therefore, the motor 2 is accurately controlled by the feedback control that takes into account the torsional torque of the drive shaft 9. Can be done.

Next, a modified example in which the embodiment is partially modified will be described.
1] In the above embodiment, an example of a relative angle difference profile set so as to rise sharply from the origin and gradually converge with respect to the upper limit on the acceleration side has been described, but at least if it converges with respect to the upper limit on the acceleration side. Any relative angle difference profile can often be adopted.
As shown in FIG. 11A, it is also possible to adopt a relative angle difference profile that gradually rises from the lower limit on the deceleration side and gradually converges on the upper limit on the acceleration side. The relative angular velocity is set by differentiating the relative angular velocity profile (FIG. 11 (b)), and the angular acceleration is set by differentiating the relative angular velocity (FIG. 11 (c)).

2] In the above embodiment, an example of a power train consisting of an in-line 4-cylinder reciprocating engine and an AT mission has been described, but the present invention is not limited to this, and any power train, for example, a power train consisting of an 8-cylinder reciprocating engine and an AT mission, or It may be a power train consisting of a V-type engine and a CVT.

3] In addition, a person skilled in the art can carry out the embodiment in a form in which various modifications are added to the above-described embodiment or in a combination of the respective embodiments without deviating from the gist of the present invention. It also includes various modified forms.

1 engine 2 motor 3 AT
4 Differential mechanism 5 Wheels 9 Drive shaft 12 2nd clutch 13 Driven side actuating part 14 Driven side actuating part 20 VCM
PT powertrain

Claims (5)

A power source composed of an engine and a motor, a transmission connected to the power source so as to transmit a driving force via an intermittent clutch, and a drive-side operating portion and the driving portion between the transmission and the wheels. A hybrid including a differential mechanism including a driven side operating unit driven by a driving side operating unit, and a control means for outputting a rotation speed and a torque command signal to the engine and the motor, respectively, and controlling the engaged state of the clutch. In the vehicle control method
Preparation for setting the amount of movement for shifting from the deceleration contact state to the acceleration contact state between the driving side operating portion and the driven side operating portion as a relative angle difference when the vehicle shifts from the deceleration state to the acceleration state. Steps and
After the clutch is engaged, after a period of transition from the deceleration contact state to the acceleration contact state elapses , the angular velocity convergence step that controls the motor so as to converge the relative angular velocity between the driving side operating portion and the driven side operating portion. ,
A method for controlling a hybrid vehicle, which comprises. A coasting step in which the engine is stopped and the clutch is disengaged when the driver releases the acceleration operation.
When the acceleration operation by the driver is executed, the clutch engagement step of engaging the clutch after starting the engine and the clutch engagement step
The hybrid vehicle control method according to claim 1, wherein the hybrid vehicle has. The hybrid according to claim 1 or 2, wherein in the angular velocity convergence step, the motor is open-loop controlled according to a preset relative angle difference map between the driving side operating portion and the driven side operating portion. How to control the vehicle. Any one of claims 1 to 3, further comprising an initial state setting step in which the clutch is temporarily controlled in the engaging direction to set the initial state of the relative angle difference before the angular velocity convergence step. The method for controlling a hybrid vehicle according to the section. The control of a hybrid vehicle according to any one of claims 1 to 4, further comprising a vibration damping control step for feedback-controlling the motor by adding a torsional torque of a drive shaft after the angular velocity convergence step. Method.

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