JPH1182087A - Driving force control system of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce driving forces according to accelerator travels in a hybrid vehicle for preset plural driving states of different transmission gear ratios including forward driving and reverse driving. SOLUTION: If a hydrid vehicle is judged to be running back (SA1), a mode- five is selected which runs the vehicle by keeping the engine running and controling the regenerative braking torque of the motor generator according to the accelerator manipulated variable of a driver (SA5). At the same time, the regenerative braking torque controlled according to the accelerator manipulated variable θAC is set slightly small as compared with forward driving (AS6). This control offers appropriate driving forces in dependence on both forward driving and reverse driving to thus improve the driveability and also the design latitude of the automatic transmission, even of those that are obliged to select a relatively higher gear ratio for the reverse gear owing to appropriate gear ratios set for the forward gears.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force control apparatus for a hybrid vehicle, and more particularly to a hybrid vehicle having cooperative control means for driving the vehicle by controlling the reaction torque of a motor generator with an engine in an operating state. It is about.

[0002]

2. Description of the Related Art A generator is arranged on a first shaft coaxial with an output shaft of an engine, and an electric motor and an automatic transmission are arranged on a second shaft provided in parallel with the first shaft. Connection of rotation transmission means such as a sprocket / chain device or a gear device connecting the first shaft and the second shaft to transmission of the engine output torque on one of the first shaft and the second shaft; A hybrid vehicle having a disconnecting clutch means is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-6720.
No. 8, for example. In such a hybrid vehicle, the clutch means is disengaged during normal running, and the electric motor is driven by electric power generated by driving the generator by the engine to run. On the other hand, when the electric motor is out of order or when high output is required, the clutch means is connected, and instead of or in combination with the power of the electric motor,
Drive by driving the engine.

[0003]

In the above-mentioned automatic transmission, the gear ratio of the gear unit is generally determined so that a predetermined gear ratio can be obtained in the forward gear. Inappropriate, the driving force (creep torque) when the accelerator operation amount is zero is too large or too small, or the rate of change of the driving force with respect to the change in the accelerator operation amount is too large or too small, so that it is always excellent. Driving operability was not obtained in some cases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to reduce the accelerator operation amount in each of a plurality of predetermined operating states such as forward and reverse traveling with different speed ratios. To obtain an appropriate driving force.

[0005]

In order to achieve the above object, a first aspect of the present invention is to provide (a) an engine that operates by burning fuel, and (b) a motor generator that functions as at least one of an electric motor and a generator. (C) having a first rotating element connected to the engine, a second rotating element connected to the motor generator, and a third rotating element connected to the output member, (D) operating the engine and controlling the reaction torque of the motor generator in accordance with the accelerator operation amount, whereby the output member is In a driving force control device for a hybrid vehicle having cooperative control means for causing a vehicle to travel by transmitting a predetermined torque to driving wheels, (e) in a plurality of predetermined driving states, By changing the relationship between Le operation amount and a reaction force torque of the motor generator, and having a driving force changing means for changing the driving force obtained with respect to the accelerator operation amount.

[0006] The second invention is the first invention, wherein
(a) disposed between the combined distribution mechanism and the drive wheels, and provided with at least a forward gear for traveling forward and a reverse gear for traveling backward, and a gear ratio of the forward gear and the reverse gear. Having automatic transmissions with different absolute values,
(b) The driving force changing means changes the relationship between the accelerator operation amount and the reaction torque of the motor generator depending on whether the vehicle is traveling forward or backward.

[0007]

In such a driving force control apparatus for a hybrid vehicle, the engine is driven and the reaction torque of the motor generator is controlled by the cooperative control means in accordance with the accelerator operation amount of the driver. By
While a predetermined torque is transmitted from the output member to the drive wheels to drive the vehicle, the relationship between the accelerator operation amount and the reaction torque of the motor generator changes in a plurality of operating states predetermined by the drive force changing means. To change the driving force obtained with respect to the accelerator operation amount,
An appropriate driving force can be obtained in each of a plurality of operating states. For example, when an automatic transmission having a forward gear and a reverse gear with different gear ratios is provided as in the second invention, the difference between the accelerator operation amount and the reaction torque of the motor generator depends on whether the vehicle is traveling forward or backward. If the relationship is changed, appropriate driving force can be obtained in each of the forward traveling and the reverse traveling, so that the driving operability is improved and the degree of freedom in designing the automatic transmission is increased.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, the synthesizing and distributing mechanism has three rotating elements such as a planetary gear unit and a bevel gear type differential unit that are operatively connected to each other and relatively rotated, and are mechanically operated. It is capable of combining and distributing forces, and a planetary gear device is preferably used. When a planetary gear device is used, a ring gear is used as the first rotating element, and a sun gear is used as the second rotating element.
It is desirable to use a rotating element and a carrier as the third rotating element. The output member may be a driving wheel, but may be an input member of an automatic transmission.

The hybrid vehicle according to the first aspect of the present invention does not necessarily require a transmission, but a stepped gear type transmission such as a parallel two-shaft type or a planetary gear type, or a stepless speed change ratio. It is also possible to provide a continuously variable transmission such as a belt type or a toroidal type that can be changed between the third rotating element and the driving wheels.

Further, the reaction torque control of the motor generator by the cooperative control means controls the regenerative braking torque by making the motor generator function as a generator, but also controls the regenerative braking torque by making the motor generator function as an electric motor. It may be controlled, and is appropriately determined according to the connection relationship between the combining and distributing mechanism and the engine, motor generator, output member, and the like. It is also possible to perform a series of reaction torque control using both the regenerative braking torque and the power running torque. The magnitude of the reaction torque is based on the torque ratio of the combined distribution mechanism, so that a predetermined torque corresponding to the accelerator operation amount is output from the output member. Or from arithmetic expressions.

The driving force changing means is configured to change the driving force when the vehicle travels forward or backward as in the second invention, for example, but in the driving state where the snow mode for traveling on a low μ road is selected. Various modes can be adopted, such as making the driving force smaller than normal (normal mode).

An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a skeleton diagram of a hybrid drive device 10 of a hybrid vehicle to which the present invention is applied.

In FIG. 1, a hybrid drive unit 10 is for an FR (Front Engine / Rear Drive) vehicle, and functions as an engine 12 such as an internal combustion engine that operates by burning fuel, and functions as an electric motor and a generator. A motor generator 14, a single-pinion type planetary gear set 16, and an automatic transmission 18 are provided along the front-rear direction of the vehicle, and are driven right and left from an output shaft 19 via a propeller shaft (not shown) and a differential unit. The driving force is transmitted to the driving wheels (rear wheels).

[0014] In the planetary gear device 16 is synthesized distributing mechanism for mechanically synthesizing distribute forces constitute an electric torque converter 24 together with the motor-generator 14, a ring gear 16r of the first rotating element of the first clutch CE ₁ Sun gear 1 as a second rotating element
6s is connected to the rotor shaft 14r of the motor generator 14, and the carrier 16c as the third rotating element is connected to the input shaft 26 of the automatic transmission 18. Further, the sun gear 16s and the carrier 16c is adapted to be connected by the second clutch CE _2. The automatic transmission 18
Input shaft 26 corresponds to an output member.

Further, the output of the engine 12 is transmitted rotation fluctuation and the flywheel 28 and the spring for suppressing the torque variation, the first clutch CE ₁ via a damper device 30 by the elastic member such as rubber. Each of the first clutch CE ₁ and the second clutch CE ₂ is a friction type multi-plate clutch that is engaged and released by a hydraulic actuator.

The automatic transmission 18 is a combination of a subtransmission 20 composed of a front-type overdrive planetary gear unit and a main transmission 22 having four forward and one reverse stages composed of a simple connection of three planetary gear trains. .

More specifically, the auxiliary transmission 20 is a single pini
ON type planetary gear set 32 and hydraulic actuator
Hydraulic clutch C frictionally engaged₀ , Bray
Key B ₀ And one-way clutch F₀ And is configured with
You. The main transmission 22 has three sets of single pinion type.
Planetary gear units 34, 36, 38, and hydraulic actuator
Hydraulic clutch C frictionally engaged by₁ ,
C_Two , Brake B₁ , B_Two , B_Three , B_Four And a one-way club
Switch F₁ , F_Two It is comprised including.

The hydraulic circuit 40 is energized and de-energized by the solenoid valves SL1 to SL4 shown in FIG.
Is switched or the hydraulic circuit 40 is mechanically switched by a manual shift valve connected to the shift lever 42, so that the clutches C ₀ , C
₁ , C ₂ and brakes B ₀ , B ₁ , B ₂ , B ₃ , B ₄ are respectively engaged and disengaged, and as shown in FIG. 3, the neutral (N) and the five forward steps (1st to 5th) ), And each of the first reverse speeds (Rev) is established.

The automatic transmission 18 and the electric torque converter 24 are constructed substantially symmetrically with respect to the center line, and the lower half of the center line is omitted in FIG.

In the clutch, brake, and one-way clutch columns of FIG. 3, "○" indicates engagement, and "●" indicates that the shift lever 42 is in the engine brake range, such as the "3", "2", and "L" ranges. Engaged when operated to the low speed range of
A blank indicates non-engagement.

In this case, the neutral N, the reverse gear Rev, and the engine brake range are established when the hydraulic circuit 40 is mechanically switched by a manual shift valve mechanically connected to the shift lever 42. The shifts between the first shift stages and the fifth shift stages are electrically controlled by solenoid valves SL1 to SL4. Further, the speed ratio of the forward shift speed gradually decreases from 1st to 5th, and the 4th speed ratio i ₄ = 1. On the other hand, the speed ratio of the reverse gear (Rev) is a relatively large value of -4.550 for the sake of setting the gear ratio of the forward gear to an appropriate value. FIG.
Shows an example of the gear ratio of each gear.

As shown in the operation table of FIG.
Shifting between the gear stage (2nd) and third shift stage (3rd) will clutch-changing the engagement-released state of the second brake B ₂ and the third brake B ₃ together.
In order to smoothly perform this shift, the circuit shown in FIG. 4 is incorporated in the hydraulic circuit 40 described above.

In FIG. 4, reference numeral 70 indicates a 1-2 shift valve, and reference numeral 71 indicates a 2-3 shift valve.
Reference numeral 72 indicates a 3-4 shift valve. The communication state of each port of these shift valves 70, 71, 72 at each shift speed is determined by the respective shift valves 70, 7
1 and 72 are shown below. The numbers indicate the respective gears.

A third brake B ₃ is connected to an oil passage 7 to a brake port 74 communicating with the input port 73 in the first and second shift speeds among the ports of the 2-3 shift valve 71.
5 are connected. This oil passage has an orifice 7
6 is interposed, the damper valve 77 is connected between the orifice 76 and the third brake B _3.
The damper valve 77 is configured to perform a buffering action by inhalation of a small amount of hydraulic pressure when the line pressure to the third brake B ₃ is rapidly supplied.

Further numeral 78 B3 control a valve, the engagement pressure P _B3 of the third brake B ₃ The B3
It is directly controlled by the control valve 78. That is, the B-3 control valve 7
8 includes a spool 79, a plunger 80, and a spring 81 interposed therebetween. An oil passage 75 is connected to an input port 82 opened and closed by the spool 79, and the input port 82 is selectively connected to the oil path 75. output port 83 which is communicated with is connected to the third brake B _3.
Further, the output port 83 is connected to a feedback port 84 formed on the distal end side of the spool 79.

On the other hand, among the ports 85 of the 2-3 shift valve 71, the port 86 for outputting the D range pressure at the third or higher speed is connected to the oil passage 85. It is communicated via 87. Further, a linear solenoid valve SLU is connected to a control port 88 formed on the end side of the plunger 80.

Therefore, the B-3 control valve 7
8 is configured such that the pressure adjustment level is set by the elastic force of the spring 81 and the hydraulic pressure supplied to the port 85, and the elastic force of the spring 81 increases as the signal pressure supplied to the control port 88 increases. ing.

Further, reference numeral 89 in FIG.
The 2-3 timing valve 89 includes a spool 90 having a small-diameter land and two large-diameter lands, a first plunger 91, and a spring 92 and a spool 90 disposed therebetween. First
And a second plunger 93 disposed on the opposite side to the plunger 91 of the second embodiment.

An oil passage 95 is connected to a port 94 at an intermediate portion of the 2-3 timing valve 89.
Reference numeral 5 denotes a port of the 2-3 shift valve 71 which is connected to a port 96 which is communicated with the brake port 74 at the third or higher speed.

Further, the oil passage 95 branches on the way.
Port 9 opening between the small land and the large land
7 is connected via an orifice. A port 98 selectively connected to the intermediate port 94 is connected to a solenoid relay valve 100 via an oil passage 99.

[0031] Then, the linear solenoid valve SLU is connected to the port that is open to an end portion of the first plunger 91, also the second brake B ₂ is an orifice to a port that opens to the end of the second plunger 93 Connected through.

[0032] The oil passage 87 is for the purpose of supplying and discharging the hydraulic pressure to the second brake B _2, a small diameter orifice 101 and a check ball with the orifice 102 is interposed in the midway. Further, the oil passage 103 branched from the oil passage 87, the large-diameter orifice 1 having a check ball to open when the pressure discharged from the second brake B ₂
The oil passage 103 is connected to an orifice control valve 105 described below.

The orifice control valve 105 is a valve for controlling the exhaust speed from the second brake B _2. The orifice control valve 105 is provided with a second brake B at a port 107 formed at an intermediate portion so as to be opened and closed by a spool 106. _Two
The oil passage 103 is connected to a port 108 formed below the port 107 in the figure.

Port 1 to which the second brake B ₂ is connected
The port 109 formed on the upper side in FIG. 7 is a port selectively communicated with the drain port. The port 109 is connected to the port 111 of the B-3 control valve 78 via an oil passage 110. It is connected. Incidentally, this port 111 is a port that is not selectively communicating the output port 83 is connected to the third brake B _3.

A control port 112 formed at an end of the port of the orifice control valve 105 opposite to the spring for pressing the spool 106 is connected to a port 114 of the 3-4 shift valve 72 via an oil passage 113. ing. This port 114 outputs the signal pressure of the third solenoid valve SL3 at a speed lower than the third speed,
Further, it is a port for outputting a signal pressure of the fourth solenoid valve SL4 at a speed higher than the fourth speed.

Further, an oil passage 115 branched from the oil passage 95 is connected to the orifice control valve 105, and the oil passage 115 is selectively connected to a drain port.

In the 2-3 shift valve 71, a port 116 for outputting a D-range pressure at a speed lower than the second speed is opened at a portion of the 2-3 timing valve 89 where a spring 92 is disposed. The port 117 is connected via an oil passage 118. A port 119 of the 3-4 shift valve 72 which is communicated with the oil passage 87 at a speed lower than the third speed is connected to the solenoid relay valve 100 via an oil passage 120.

In FIG. 4, reference numeral 121 denotes the second
Indicates an accumulator for the brake B _2, accumulator control pressure linear solenoid valve SLN is pressure regulated in accordance with the hydraulic pressure output is supplied to the back pressure chamber. The accumulator control pressure is configured to increase as the output pressure of the linear solenoid valve SLN decreases. Therefore, the transient hydraulic pressure P _B2 for engaging / disengaging the second brake B ₂ changes at a higher pressure as the signal pressure of the linear solenoid valve SLN is lower. Other clutches C ₁ , C ₂ for shifting
Accumulator is provided in such and brake B _0, the accumulator control pressure by being allowed to act, so that the transient hydraulic pressure in the gear shifting is controlled in accordance with the torque T _I of the input shaft 26.

Further, reference numeral 122 denotes a C-0 exhaust valve, further numerals 123 denotes an accumulator for the clutch C _0. C-0 exhaust valve 1
22 is to operate to engage the clutch C ₀ in order to engine brake only at the second gear of the second speed range.

Therefore, according to the hydraulic circuit 40 described above, if the port 111 of the B-3 control valve 78 is in communication with the drain, the engagement pressure P of the third brake B _3
B3 can be directly regulated by the B-3 control valve 78, and the pressure regulation level can be changed by the linear solenoid valve SLU.

The orifice control valve 10
5 of the spool 106, if the position shown in the left half of the figure, the second brake B ₂ allows ejection pressure through the orifice control valve 105, thus second
It is possible to control the drain rate from the brake B _2.

Further, when shifting from the second gear to the third gear, the third brake B ₃ is gradually released and the second gear is released.
But not so-called clutch-to-clutch shifting gently engage the brake B ₂ is carried out, the third release transitional hydraulic pressure of the brake B ₃ which is driven by the linear solenoid valve SLU based on the input shaft torque to the input shaft 26 By controlling P _B3 , shift shock can be reduced appropriately. The control of the hydraulic pressure P _B3 based on the input shaft torque can be performed in real time by feedback control or the like, but may be performed based only on the input shaft torque at the start of shifting.

As shown in FIG. 2, the hybrid drive device 10 includes a controller 50 for hybrid control and a controller 52 for automatic shift control. Each of the controllers 50 and 52 is provided with a microcomputer having a CPU, a RAM, a ROM, and the like. A signal indicating the operation range of the shift lever 42 is supplied from the shift position sensor 44, and the input shaft rotation speed N _I. , Vehicle speed V (corresponding to output shaft speed N _O ), engine torque T _E , motor torque T _M , engine speed N _E , motor speed N _M , power storage amount S of power storage device 58 (see FIG. 5).
It reads various information such as OC, brake ON / OFF, accelerator operation amount θ _AC, and performs signal processing according to a preset program.

[0044] The engine torque T _E is determined from a throttle valve opening and the fuel injection amount, the motor torque T _M
Is obtained from the motor current and the like, and the state of charge SOC is obtained from the motor current and the charging efficiency during charging when the motor generator 14 functions as a generator.

The output of the engine 12 is controlled in accordance with the operating state by controlling the throttle valve opening, fuel injection amount, ignition timing and the like by the hybrid control controller 50.

The motor generator 14 is connected to a power storage device 58 such as a battery via an M / G controller (inverter) 56 as shown in FIG. And a charge state in which electric energy is supplied to the power storage device 58 by functioning as a generator by regenerative braking (electric braking torque of the motor generator 14 itself). The state is switched to a no-load state in which the rotor shaft 14r is allowed to rotate freely.

The first clutch CE ₁ and the second clutch CE ₂ are connected to the hybrid control controller 50.
As a result, the hydraulic circuit 40 is switched via an electromagnetic valve or the like, whereby the engaged or released state is switched.

The automatic transmission 18 is controlled by the automatic transmission control controller 52 to operate the solenoid valves SL1 to SL1.
SL4, linear solenoid valve SLU, SLT, SL
The excitation state of N is controlled, and the hydraulic circuit 40 is switched or the hydraulic control is performed, so that the shift speed is switched according to predetermined shift conditions. The shifting conditions are
For example, it is set by a shift map or the like using the running state such as the accelerator operation amount θ _AC and the vehicle speed V as parameters.

The hybrid control controller 50
For example, Japanese Patent Application No. 7-294 filed earlier by the applicant of the present application
As described in No. 148, one of the nine operation modes shown in FIG. 7 is selected according to the flowchart shown in FIG. 6, and the engine 12 and the electric torque converter 24 are operated in the selected mode.

In FIG. 6, in step S1, it is determined whether or not an engine start request has been made, for example, in order to drive the engine 12 as a power source or to rotate the motor generator 14 by the engine 12 to charge the power storage device 58. Then, it is determined whether or not a command to start the engine 12 has been issued.

Here, if there is a start request, mode 9 is selected in step S2. Mode 9, the engine 12 via the planetary gear unit 16 by the first clutch CE ₁ As apparent from FIG. 7 engaged (ON), the second clutch CE ₂ engaged (ON), the motor generator 14 , And performs engine start control such as fuel injection to start the engine 12.

[0052] This mode 9, at the time of vehicle stop is performed by the automatic transmission 18 in neutral, only the motor-generator 14 first releases the clutch CE ₁ as mode 1 during running of the power source, first Clutch CE
₁ is engaged, the motor generator 14 is operated with an output higher than the required output required for traveling, and the engine 12 is rotationally driven with a margin output higher than the required output. Further, even when the vehicle is running, it is possible to temporarily execute the mode 9 with the automatic transmission 18 in the neutral state.

On the other hand, if the determination in step S1 is denied, that is, if there is no engine start request, step S3 is executed to determine whether there is a request for braking force, for example, whether the brake is ON. Or shift lever 42
Is an engine brake range such as L or 2 (a range in which shift control is performed only at a low shift speed and engine brake and regenerative braking are applied), and whether an accelerator operation amount θ _AC is 0 or simply It is determined by whether the operation amount θ _AC is 0 or not.

If this judgment is affirmative, step S
Execute Step 4. In step S4, it is determined whether or not the state of charge SOC of power storage device 58 is equal to or greater than a predetermined maximum state of charge B. If SOC ≧ B, mode 8 is selected in step S5, and if SOC <B, step 8 is selected. Mode 6 is selected in S6. The maximum power storage amount B is the maximum power storage amount allowed to charge the power storage device 58 with electric energy, and is set to a value of, for example, about 80% based on the charging / discharging efficiency of the power storage device 58 and the like.

Mode 8 selected in step S5
As shown in FIG. 7, the first clutch CE ₁ is engaged (ON), the second clutch CE ₂ is engaged (ON), the motor generator 14 is in a no-load state, and the engine 12
Is stopped, that is, the throttle valve is closed, and the fuel injection amount is set to 0, whereby the braking force due to the rubbing rotation of the engine 12, that is, the engine brake is applied to the vehicle, and the brake operation by the driver is reduced. Driving operation becomes easy. Further, since motor generator 14 is set in a no-load state and is freely rotated, it is possible to avoid a situation where power storage amount SOC of power storage device 58 becomes excessive and impairs performance such as charge / discharge efficiency.

[0056] Mode 6 is selected in step S6, disengaging the first clutch CE ₁ As apparent from FIG. 7 (OF
F), the second clutch CE ₂ is engaged (ON), the engine 12 is stopped, and the motor generator 14 is charged, and the motor generator 14 is rotationally driven by the kinetic energy of the vehicle. Since the power storage device 58 is charged and a regenerative braking force such as an engine brake is applied to the vehicle, the braking operation by the driver is reduced and the driving operation is facilitated.

Further, since the first clutch CE ₁ is released and the engine 12 is shut off, there is no energy loss due to the rubbing of the engine 12 and the operation is executed when the state of charge SOC is smaller than the maximum state of charge B. Therefore, the amount of charge SOC of the power storage device 58 does not become excessive and the performance such as charge / discharge efficiency is not impaired.

On the other hand, if the judgment in step S3 is negative, that is, if there is no request for the braking force, step S7 is executed.
Is performed, and it is determined whether or not the start of the engine is requested, for example, based on whether or not the vehicle is stopped during traveling using the engine 12 as a power source such as mode 3, that is, whether or not the vehicle speed V ≒ 0.

If this determination is affirmative, it is determined in step S8 whether or not the "P" range or the "N" range, which is the non-drive range, has been selected by the shift lever 42. If the "N" range has not been selected, that is, if a drive range such as the "D" range or the "R" range has been selected, step S9 is performed.
To select mode 5, and if the "P" range or "N" range is selected, select mode 7 in step S10.

Mode 5 selected in step S9
Is a first clutch CE ₁ As apparent from FIG. 7 engaged (ON), and second releasing clutch CE ₂ (OFF),
With the engine 12 in a predetermined operating state, the accelerator operation amount θ
_The vehicle starts or runs by controlling the regenerative braking torque (reaction torque) of the motor generator 14 based on a predetermined data map or arithmetic expression using _AC as a parameter. Even when the amount θ _AC is substantially zero, a predetermined regenerative braking torque is generated so that a predetermined creep torque is obtained. The mode 5 selected in step S9
Corresponds to the cooperative control means.

More specifically, assuming that the gear ratio of the planetary gear set 16 is ρ _E , the engine torque T _E : the output torque of the planetary gear set 16: the motor torque T _M = 1: (1+
ρ _E ): ρ _E. For example, if the gear ratio ρ _E is set to about 0.5 which is a general value, the motor generator 14 shares half of the engine torque T _E , so that the engine torque T A torque about 1.5 times _E is output from the carrier 16c.

That is, it is possible to start a high torque of (1 + ρ _E ) / ρ _E times the torque of the motor generator 14. Further, if the motor current is cut off to place the motor generator 14 in a no-load state, the rotor shaft 14r
Is only rotated in the reverse direction, the output from the carrier 16c becomes 0, and the vehicle stops (creep torque = 0).

That is, the planetary gear set 16 in this case is
It functions as a starting clutch and torque amplifying device
Yes, motor torque (regenerative braking torque) T_MFrom 0
By increasing the reaction force by increasing the
Luc T_M(1 + ρ_E) / Ρ _ETimes, engine torque T_E
(1 + ρ_E) The vehicle starts smoothly with twice the output torque
It can be done.

In this embodiment, a motor generator having a torque capacity approximately ρ _E times the maximum torque of the engine 12, that is, a motor generator 14 as small and small as possible while ensuring the required torque is used. ,
The device is compact and inexpensive. In this embodiment, the output of the engine 12 is increased by increasing the throttle valve opening and the fuel injection amount in response to the increase in the motor torque T _M. thereby preventing engine stall or the like due to the reduction in the number N _E.

The mode 7 selected in step S10 is
As can be appreciated the first clutch CE ₁ engages from FIG 7 (O
N), and second releasing clutch CE ₂ and (OFF), the engine 12 as a driving state, in which the electrically neutral motor-generator 14 as a no-load condition, the rotor shaft 14r is opposite direction of the motor-generator 14 The rotation of the input shaft 2 of the automatic transmission 18
The output for 6 becomes zero. Accordingly, it is not necessary to stop the engine 12 one by one when the vehicle is stopped while running using the engine 12 as a power source, such as in mode 3, and the engine can be started in mode 5 substantially.

On the other hand, if the determination in step S7 is negative, that is, if there is no request to start the engine, step S11 is executed, and the required output Pd is set to the first preset value.
It is determined whether the value is equal to or less than the determination value P1. The required output Pd is an output necessary for the running of the vehicle including the running resistance, and is the accelerator operation amount θ _AC , its changing speed, the vehicle speed V (the output shaft rotation speed N _O ),
Based on the gear position of the automatic transmission 18 and the like, it is calculated by a predetermined data map, an arithmetic expression, or the like.

The first judgment value P1 is a boundary value between a middle load region where the vehicle runs only using the engine 12 as a power source and a low load region where the vehicle runs only using the motor generator 14 as a power source. In consideration of the energy efficiency, the exhaust gas amount, the fuel consumption amount, and the like are determined by experiments and the like so as to be as small as possible.

If the determination in step S11 is affirmative,
That is, when the required output Pd is equal to or less than the first determination value P1, it is determined in step S12 whether or not the state of charge SOC is equal to or greater than the preset minimum amount of charge A. If SOC ≧ A, the mode 1 is determined in step S13. Select On the other hand, SOC <A
If so, the mode 3 is selected in step S14. The minimum power storage amount A is a minimum power storage amount that is allowed to take out electric energy from power storage device 58 when traveling using motor generator 14 as a power source, and is, for example, 70% based on charge / discharge efficiency of power storage device 58 and the like. The value of degree is set.

[0069] The mode 1, the 7 released as apparent the first clutch CE ₁ from to (OFF), the second clutch CE ₂ engaged (ON), to stop the engine 12,
The motor generator 14 is driven to rotate at the required output Pd, and the vehicle is started or run using only the motor generator 14 as a power source. The motor generator 14 is operated (torque generation) with a predetermined output so that a predetermined creep torque is obtained even when the accelerator is OFF, that is, when the accelerator operation amount θ _AC is substantially zero. Even if the mode 1 is selected, because the engine 12 first clutch CE ₁ is released is interrupted, the mode 6 less similarly pulled rubbing loss, by appropriate shift control of the automatic transmission 18 Efficient motor drive control is possible.

This mode 1 is executed when the required output Pd is in a low load region where the required output Pd is equal to or less than the first determination value P1 and the state of charge SOC of the power storage device 58 is equal to or greater than the minimum state of charge A. Energy efficiency is superior to that when traveling as a power source, fuel consumption and exhaust gas can be reduced, and the state of charge SOC of the power storage device 58 has a minimum state of charge A
The performance such as charge / discharge efficiency is not impaired.

The mode 3 selected in step S14 is
As is clear from FIG. 7, the first clutch CE ₁ and the second clutch CE ₁
The clutch CE ₂ is engaged (ON) together, the engine 12 is driven, the motor generator 14 is charged by regenerative braking, and is generated by the motor generator 14 while the vehicle is running at the output of the engine 12. Electric energy is charged in the power storage device 58. The engine 12 is operated at an output higher than the required output Pd, and the current control of the motor generator 14 is performed so that the motor generator 14 consumes a marginal power greater than the required output Pd.

On the other hand, if the determination in step S11 is negative, that is, if the required output Pd is larger than the first determination value P1, in step S15, the required output Pd is determined.
It is determined whether d is greater than the first determination value P1 and less than the second determination value P2, that is, whether P1 <Pd <P2.

The second determination value P2 is a boundary value between a middle load region where the vehicle runs only using the engine 12 as a power source and a high load region where the vehicle runs using both the engine 12 and the motor generator 14 as the power sources. In consideration of energy efficiency including time, exhaust gas amount, fuel consumption amount and the like are determined in advance by experiments and the like so as to minimize the amount of exhaust gas and fuel consumption.

If P1 <Pd <P2, it is determined in step S16 whether or not SOC ≧ A. If SOC ≧ A, mode 2 is selected in step S17, and SOC <A
In the case of, mode 3 is selected in step S14.

If Pd ≧ P2, step S18
It is determined whether or not SOC ≧ A. If SOC ≧ A, mode 4 is selected in step S19, and if SOC <A, mode 2 is selected in step S17.

In the mode 2, the first clutch CE ₁ and the second clutch CE ₂ are both engaged (ON), the engine 12 is operated at the required output Pd, and the motor generator 14 is operated, as is apparent from FIG. Under no load condition, the vehicle is run using only the engine 12 as a power source.

In mode 4, the first clutch CE ₁ and the second clutch CE ₂ are both engaged (ON), the engine 12 is in an operating state, and the motor generator 14 is rotationally driven. The vehicle is caused to travel at a high output using both of the generators 14 as power sources.

Mode 4 is executed in a high load region where the required output Pd is equal to or larger than the second determination value P2.
And the motor generator 14 are used together, so that the energy efficiency is not significantly impaired as compared with the case where the vehicle runs using only one of the engine 12 and the motor generator 14 as a power source, and the fuel consumption and exhaust gas can be reduced. . In addition, since the process is executed when the storage amount SOC is equal to or more than the minimum storage amount A, the storage amount SOC of the power storage device 58 does not decrease below the minimum storage amount A, and the performance such as charging and discharging efficiency is not impaired.

To summarize the operating conditions of the above modes 1 to 4, if the state of charge SOC ≧ A, in the low load region of Pd ≦ P1, the mode 1 is selected in step S13 and the vehicle runs using only the motor generator 14 as a power source. And P1 <P
In the medium load region of d <P2, mode 2 is selected in step S17, and the vehicle travels using only the engine 12 as a power source.
In the high load region of ≤Pd, mode 4 is selected in step S19, and the vehicle travels using both the engine 12 and the motor generator 14 as power sources.

When SOC <A, the required output P
The power storage device 58 is charged by executing the mode 3 of step S14 in the middle and low load region where d is smaller than the second determination value P2. However, in the high load region where the required output Pd is equal to or more than the second determination value P2, in step S17. Mode 2 is selected, and high-power traveling is performed by the engine 12 without charging.

The mode 2 of step S17 is such that P1 <Pd
<P2 in the middle load range and SOC ≧ A, or P
This is executed in the high load region where d ≧ P2 and when SOC <A.
Since the energy efficiency of the engine 12 is superior to that of the engine 12, the fuel consumption and exhaust gas can be reduced as compared with the case where the vehicle runs using the motor generator 14 as a power source.

In a high load range, the vehicle travels in mode 4 in which the motor generator 14 and the engine 12 are used together.
However, when the state of charge SOC of the power storage device 58 is smaller than the minimum state of charge A, the operation in the mode 2 using only the engine 12 as a power source is performed, so that the state of charge SOC of the power storage device 58 is minimized. It is avoided that the charge amount becomes smaller than the storage amount A and the performance such as charge / discharge efficiency is impaired.

Next, the characteristic portion of the present embodiment to which the present invention is applied, that is, when the vehicle is moving forward and when the vehicle is traveling reversely with different speed ratios,
A control operation for obtaining an appropriate driving force with respect to the accelerator operation amount θ _AC will be described based on the flowchart of FIG. In this control operation, step SA6 corresponds to the driving force changing means, and is executed by the hybrid control controller 50.

In FIG. 8, in step SA1, it is determined whether or not the shift lever 42 has been operated to the R range based on the signal supplied from the shift position sensor 44. If this determination is denied, in step SA2, normal traveling control is performed according to the operation mode determination subroutine of FIG.

On the other hand, if the determination in step SA1 is affirmative, it is determined in step SA3 whether or not the state of charge SOC of power storage device 58 is equal to or greater than predetermined value C. The predetermined value C is set so that the vehicle can travel backward for a certain time and distance even when the mode 1 in which the vehicle runs with the motor generator 14 as the power source is selected.

If the determination in step SA3 is affirmative, the mode 1 is selected in step SA4, and the vehicle runs backward using the motor generator 14 as a power source. Here, the motor generator 1
4 is capable of performing more precise output torque control than the engine 12, so that the output torque of the motor generator 14 (motor torque T _M ) obtained with respect to the accelerator operation amount θ _AC
Is set lower than the forward speed in consideration of the speed ratio of the reverse gear (Rev), and the automatic transmission 1
8, the input torque transmitted to the input shaft 26 of the E.8 is relatively reduced as compared with that at the time of forward movement, so that an appropriate driving force can be obtained with respect to the accelerator operation amount θ _AC regardless of a large gear ratio. I have.

On the other hand, if the determination in step SA3 is negative, in step SA5, the engine 12 is brought into the operating state, and the regenerative braking torque (reaction torque) of the motor generator 14 is controlled according to the accelerator operation amount θ _AC. Thus, the mode 5 for driving the vehicle is selected.

Subsequently, at step SA6, the reverse traveling data set in advance in consideration of the gear ratio of the reverse gear (Rev) so that the regenerative braking torque of the motor generator 14 becomes lower than that at the time of forward traveling. Control is performed according to the accelerator operation amount θ _AC based on a map, an arithmetic expression, or the like. As a result, the input torque transmitted from the carrier 16c to the input shaft 26 of the automatic transmission 18 is relatively reduced as compared with when the vehicle is moving forward, and an appropriate driving force for the accelerator operation amount θ _AC regardless of the large gear ratio. Is obtained. Engine 12
If the output of the throttle valve is almost the same,
The rotational speed N _M of the motor generator 14 is increased to the reverse rotation side as shown by the broken line in FIG. 9 with the decrease in the regenerative braking torque, and the engine rotation speed N _E is correspondingly increased to the forward rotation side. . As shown in FIG. 10, if the throttle valve opening (output) is constant, the engine speed N _E
Because the engine torque T _E is in a relationship of inverse proportion, the engine torque T _E with the increase of the engine rotational speed N _E is caused to decrease, the engine torque T _E with respect to the regenerative braking torque of the motor generator 14 is 1 / [rho Number of rotations N that becomes _E
Balance with _E. Incidentally, FIG. 9 is a diagram showing a comparison time of forward when the vehicle is stopped and the rotational speed N _M of the reverse time, the N _E.

As described above, according to the present embodiment, if it is determined in step SA1 that the shift lever 42 has been operated to the R range, the engine 12 is brought into the operating state in step SA5, and the driver By controlling the regenerative braking torque of the motor generator 14 in accordance with the accelerator operation amount θ _AC of the vehicle, the mode 5 for running the vehicle is selected, and in step SA6, the regenerative braking torque of the motor generator 14 ) Is controlled in accordance with the accelerator operation amount θ _AC based on a predetermined data map or an arithmetic expression for reverse traveling so as to be lower than at the time of forward traveling in consideration of the gear ratio of Since the driving force generated from the drive wheels is appropriately controlled irrespective of the gear ratio, changing the reverse gear in order to set the gear ratio of the forward gear to an appropriate value is performed. Even if the automatic transmission 18 in which the speed ratio has to be set to a relatively large value is used, appropriate driving force can be obtained in each of the forward traveling and the reverse traveling, so that the driving operability is improved, and Automatic transmission 1
8 has a higher degree of freedom in design.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be applied to other embodiments.

For example, in the above-described embodiment,
Although the automatic transmission 18 having five speeds and five forward speeds has been used, as shown in FIG. 11, the automatic transmission 60 comprising only the main transmission 22 without the sub-transmission 20 is shown. It is also possible to adopt the configuration shown in FIG. 12 and perform the speed change control at four forward speeds and one reverse speed.

In the above-described embodiment, when the shift lever 42 is determined not to be operated in the R range in step SA1 when the vehicle is moving forward or when the vehicle is stopped, in step SA2, the operation mode determination subroutine shown in FIG. In particular, when the vehicle is moving forward in mode 5, the regenerative braking torque of the motor generator 14 obtained with respect to the accelerator operation amount θ _AC is always set to an appropriate value. The regenerative braking torque is controlled by using a plurality of data maps and arithmetic expressions determined for each forward gear in consideration of the gear ratios of the forward gears (1st to 5th). An appropriate driving force may be obtained.

The present invention can be applied in various other modes without departing from the gist of the present invention.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram illustrating a configuration of a hybrid drive device of a hybrid vehicle to which the present invention is applied.

FIG. 2 is a diagram illustrating a control system provided in the hybrid drive device of FIG.

FIG. 3 is a diagram illustrating the operation of an engagement element that establishes each shift speed of the automatic transmission of FIG. 1;

FIG. 4 is a diagram showing a part of a hydraulic circuit of the automatic transmission of FIG. 1;

FIG. 5 is a diagram illustrating a connection relationship between the hybrid control controller of FIG. 2 and an electric torque converter.

FIG. 6 is a flowchart illustrating a basic operation of the hybrid drive device of FIG. 1;

FIG. 7 shows each mode 1 to 9 in the flowchart of FIG.
It is a figure explaining the operation state of.

FIG. 8 is a flowchart illustrating a main part of a control operation that is a feature of the present invention.

FIG. 9 is a diagram illustrating a mutual relationship between the rotation speeds of a sun gear, a carrier, and a ring gear included in the planetary gear device.

10 is a diagram showing the interrelationship of the case of the throttle valve opening degree constant engine torque T _E and the rotational speed N _E.

FIG. 11 is a skeleton diagram illustrating a configuration of a hybrid drive device including an automatic transmission different from the embodiment of FIG. 1;

12 is a diagram illustrating the operation of an engagement element that establishes each shift speed of the automatic transmission in FIG.

[Explanation of symbols]

 12: Engine 14: Motor generator 16: Planetary gear unit (combined distribution mechanism) 16r: Ring gear (first rotating element) 16s: Sun gear (second rotating element) 16c: Carrier (third rotating element) 26: Input shaft (output) 50) Hybrid controller Step S9: Cooperative control means Step SA6: Driving force changing means

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // F16H 59:18

Claims (2)

[Claims] An engine that operates by burning fuel, a motor generator that functions as at least one of an electric motor and a generator, a first rotating element connected to the engine, and a second rotation connected to the motor generator And a third rotating element connected to the output member, and a combining and distributing mechanism for mechanically combining and distributing the force therebetween. A driving force control device for a hybrid vehicle having cooperative control means for controlling a reaction torque of the motor generator according to the amount to transmit a predetermined torque from the output member to driving wheels to drive the vehicle, In a plurality of determined operating states, the relationship between the accelerator operation amount and the reaction torque of the motor generator is changed. The driving force control apparatus for a hybrid vehicle, comprising a driving force changing means for changing the driving force obtained with respect to the accelerator operation amount. 2. A shift gear disposed between the combined distribution mechanism and the drive wheels, the shift gear having at least a forward gear for traveling forward and a reverse gear for traveling backward, and having the forward gear and the reverse gear. An automatic transmission having different absolute values of the ratio, wherein the driving force changing means changes a relationship between the accelerator operation amount and a reaction torque of the motor generator depending on whether the vehicle is traveling forward or traveling backward. The driving force control device for a hybrid vehicle according to claim 1, wherein: