JP2004112995A - Drive control device for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further improve the fuel efficiency in a hybrid vehicle which is provided with an engine and an electric motor as power sources for running the vehicle, and uses the engine and the electric motor selectively according to operating conditions.
If it is determined in steps SA1 to SA3 that the vehicle is traveling at a reduced speed, the fuel supply to the engine is stopped in step SA4. Further, it is determined whether the brake ON at step SA6, if brake ON, with disconnecting the engine by releasing the first clutch CE ₁ in step SA10, an amount corresponding motor generator corresponding to an engine braking force at step SA9 14 regenerative torque is increased.
[Selection diagram] FIG.

Description

The present invention relates to a drive control device for a hybrid vehicle, and more particularly, to control during deceleration driving.

In a normal engine vehicle that runs using an engine that operates by fuel combustion as a power source, fuel supply to the engine is stopped at a speed equal to or higher than a predetermined vehicle speed when the throttle valve is almost fully closed and the vehicle is running at a reduced speed. A fuel cut technique is described in Patent Document 1, for example. According to such a technique, fuel is not supplied to the engine during deceleration running that does not require engine torque, so that fuel efficiency is improved.

JP-A-58-187565 JP-A-7-67208

On the other hand, a hybrid vehicle that includes an engine and an electric motor as a power source when the vehicle travels, and that uses the engine and the electric motor according to the driving conditions and travels properly is described in Patent Document 2, for example. In such a hybrid vehicle, fuel supply control technology for the engine during deceleration traveling has not been established yet.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide an engine and an electric motor as a power source for driving a vehicle, and to provide the engine and the electric motor according to operating conditions. Another object of the present invention is to further improve fuel efficiency in a hybrid vehicle that travels in a plurality of operation modes having different operation states.

In order to achieve the above object, a first aspect of the present invention includes an engine that operates by burning fuel and an electric motor that operates with electric energy as a power source when the vehicle travels. In a hybrid vehicle running in a plurality of operation modes in which the operating states of the electric motors are different, (a) clutch means for disconnecting the engine from the electric motor, and (b) releasing the clutch means when the brake is ON to release the engine. (C) braking force supplementing means for supplementing a braking force corresponding to an engine braking force by regenerative braking when the engine is disconnected by the engine separating means. And

According to a second aspect, in the drive control device for a hybrid vehicle according to the first aspect, the engine disconnecting means releases the clutch means on condition that fuel supply to the engine is stopped during deceleration driving. It is characterized by separating the engine.

According to a third aspect, in the drive control device for a hybrid vehicle according to the first aspect, the engine disconnecting means releases the clutch means and disconnects the engine on condition that a catalyst temperature is equal to or higher than a predetermined value. I do.

According to a fourth aspect, in the drive control device for a hybrid vehicle according to the first aspect, the engine disconnecting unit releases the clutch unit on the condition that the driving range is a driving range in which the electric motor is used as a power source to start the engine. It is characterized by separating.

According to a fifth aspect of the present invention, there is provided a vehicle including an engine that operates by burning fuel, and an electric motor that operates with electric energy as a power source when the vehicle is running, and in which the operating states of the engine and the electric motor differ depending on operating conditions. (A) a clutch means for disconnecting the engine from the electric motor; and (b) an engine disconnecting means for releasing the clutch means and disconnecting the engine from the electric motor during deceleration travel. (C) braking force supplementing means for supplementing braking force corresponding to engine braking force with regenerative braking when the engine is separated by the engine separating means.

According to a sixth aspect, in the drive control device for a hybrid vehicle according to the fifth aspect, the engine disconnecting unit releases the clutch unit and disconnects the engine on condition that fuel supply to the engine is stopped. It is characterized by.

According to a seventh aspect, in the drive control device for a hybrid vehicle according to the fifth aspect, the engine disconnecting means releases the clutch means and disconnects the engine on condition that a catalyst temperature is equal to or higher than a predetermined value. I do.

An eighth invention is the drive control device for a hybrid vehicle according to the fifth invention, wherein the engine disconnecting means releases the clutch means to release the engine on condition that the driving area is a driving range in which the electric motor runs as a power source. It is characterized by separating.

A ninth aspect of the present invention includes an engine that operates by burning fuel and an electric motor that operates with electric energy as a power source when the vehicle travels, and the operating states of the engine and the electric motor differ depending on operating conditions. A hybrid vehicle running in the operation mode of (a), comprising: (a) fuel supply stopping means for stopping fuel supply to the engine; and (b) engine disconnecting means for releasing the clutch means to disconnect the engine, (c) When the vehicle is running at a reduced speed, the engine is separated by the engine disconnecting means, and the fuel supply to the engine is stopped by the fuel supply stopping means.

A tenth invention is characterized in that, in the drive control device for a hybrid vehicle according to the ninth invention, the engine disconnecting means releases the clutch means and disconnects the engine on condition that the brake is ON.

According to an eleventh aspect, in the drive control device for a hybrid vehicle according to the ninth aspect, the engine disconnecting unit releases the clutch unit and disconnects the engine on condition that a catalyst temperature is equal to or higher than a predetermined value. I do.

A twelfth invention is the drive control device for a hybrid vehicle according to the ninth invention, wherein the engine disconnecting means releases the clutch means on condition that the driving area is a driving range in which the electric motor is used as a power source to operate the engine. It is characterized by separating.

According to a thirteenth aspect, in the drive control device for a hybrid vehicle according to the ninth aspect, a power storage device for supplying electric energy to the electric motor is provided.

According to a fourteenth aspect, in the drive control device for a hybrid vehicle according to any one of the first to thirteenth aspects, an automatic transmission is disposed between the engine and the electric motor and the drive wheels. And

According to the first invention, the engine is disconnected from the electric motor when the brake is ON, and the braking force corresponding to the engine braking force is supplemented by the regenerative braking by the braking force supplementing means. It does not cause the driver to feel uncomfortable due to the change, and the power storage device can be charged by regenerative braking to improve fuel efficiency.

In the fifth invention, the engine is disconnected from the electric motor during deceleration running that does not require engine torque, and the braking force corresponding to the engine braking force is supplemented by the regenerative braking by the braking force supplementing means. Therefore, the braking force does not change and the driver does not feel uncomfortable, and the power storage device can be charged by regenerative braking to improve fuel efficiency.

According to the ninth aspect, during deceleration traveling that does not require engine torque, the clutch means is released to disconnect the engine, and the fuel supply to the engine is stopped by the fuel supply stopping means, thereby improving fuel efficiency.

Here, the present invention combines or distributes the output of the engine and the electric motor by a switching type in which the power source is switched by, for example, connecting / disconnecting power transmission by a clutch, or by combining and distributing a planetary gear device. The present invention can be applied to various types of hybrid vehicles including an engine and an electric motor as power sources for running the vehicle, such as a mixed type that uses an electric motor and an assist type that uses an electric motor as a supplement.

Also, during deceleration running in which the fuel supply stopping means stops fuel supply to the engine, for example, it is determined whether or not the time during which the accelerator operation means such as an accelerator pedal is not operated has exceeded a predetermined time, or Is substantially zero, and the deceleration running determining means for determining whether or not the rate of change of the vehicle speed has become equal to or less than a predetermined value.

The driving range in which the electric motor runs with the power source as the power source is not only the motor running region in which the driving is performed with the electric motor alone as the power source, but also the engine + motor running range in which both the electric motor and the engine run in the power source. Is also good. In the case of the engine + motor traveling region, it is desirable to control the motor torque in anticipation of a delay in starting the engine during re-acceleration.

In a hybrid vehicle, an operation region such as a motor traveling region in which the vehicle travels using only the electric motor as a power source or an engine traveling region in which the vehicle travels using only the engine as a power source is set. The operation state such as the accelerator operation amount and the vehicle speed is set as a parameter by using a map or an arithmetic expression so as to minimize the fuel consumption and the fuel consumption. Further, it is desirable that the engine resonance region where the drive system resonates due to the vibration of the engine and NVH (noise, vibration, rough riding comfort) deteriorates be a motor traveling region in which the vehicle travels using only the electric motor as a power source.

Further, the engine disconnecting means when the catalyst temperature is low when stopped rotating disconnect the engine, then because the generation of exhaust gas of the NO _X and CO, etc. when starting the engine is a concern, the catalyst temperature is lower than a predetermined value Sometimes it is desirable to provide engine disconnection limiting means that prohibits engine disconnection by the engine disconnecting means.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a skeleton view of a hybrid drive device 10 of a hybrid vehicle including a drive control device according to one embodiment of the present invention.

In FIG. 1, a hybrid drive unit 10 is for an FR (front engine / rear drive) vehicle, and includes an engine 12 such as an internal combustion engine that operates by burning fuel, and a motor generator having functions as an electric motor and a 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 left and right drive wheels are provided from an output shaft 19 via a not-shown propeller shaft or a differential device. (Rear wheel).

Planetary gear set 16 is a synthetic distributing mechanism for mechanically synthesizing force distributor, constitutes an electric torque converter 24 together with the motor-generator 14, the ring gear 16r is connected to the engine 12 via the first clutch CE _1, The sun gear 16s is connected to a rotor shaft 14r of the motor generator 14, and the carrier 16c is connected to an 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 first clutch CE ₁ corresponds to a clutch unit that disconnects the engine 12 from the drive system.

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 an auxiliary transmission 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.

Specifically, the configuration auxiliary transmission 20 is a planetary gear device 32 of a single pinion type, the clutch C ₀ of hydraulic to be frictionally engaged by a hydraulic actuator, it includes a brake B _0, and a one-way clutch F ₀ Have been. The main transmission 22 includes a third set of single-pinion type planetary gear unit 34, 36, 38, clutch C ₁ hydraulic that are frictionally applied by hydraulic actuators, C _2, the brake B _1, B _2, B ₃ and B ₄ and one-way clutches F ₁ and F ₂ are provided.

The hydraulic circuit 40 is switched by energization and non-excitation of the solenoid valves SL1 to SL4 shown in FIG. 2, or the hydraulic circuit 40 is mechanically switched by a manual shift valve connected to a shift lever (not shown). As a result, the clutches C ₀ , C ₁ , C ₂ and the brakes B ₀ , B ₁ , B ₂ , B ₃ , B ₄ are respectively engaged and released, and the neutral (N ), Five forward speeds (1st to 5th), and one reverse speed (Rev).

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

In the column of clutch, brake, and one-way clutch in FIG. 3, “係 合” indicates engagement, and “●” indicates that the shift lever shifts to an engine brake range, for example, a low speed range such as “3”, “2”, and “L” range. Engage when operated, and 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 a shift lever, and the forward gear is established. Shifts between 1st to 5th 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 speed ratio i ₄ = 1 at _4th . FIG. 3 shows an example of the gear ratio of each gear.

As shown in the operation table of FIG. 3, the shift between the second speed stage (2nd) and third shift stage (3rd), the engagement of the second brake B ₂ and the third brake B ₃ -A clutch-to-clutch shift that changes both release states. The circuit shown in FIG. 4 is incorporated in the above-described hydraulic circuit 40 in order to smoothly perform this shift.

に お い て In FIG. 4, reference numeral 70 denotes a 1-2 shift valve, reference numeral 71 denotes a 2-3 shift valve, and reference numeral 72 denotes a 3-4 shift valve. The communication state of each port of the shift valves 70, 71, 72 at each shift speed is as shown below each shift valve 70, 71, 72. In addition, the number shows each shift stage.

A third brake B ₃ is connected via an oil passage 75 to a brake port 74 that communicates with the input port 73 at the first shift speed and the second shift speed among the ports of the 2-3 shift valve 71. This is the oil passage which orifice 76 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.

The reference numeral 78 denotes a B3 control valve, which is the engagement pressure P _B3 of the third brake B ₃ to be controlled directly by the B3 control valve 78. That is, the B-3 control valve 78 includes a spool 79, a plunger 80, and a spring 81 interposed therebetween, and an oil passage 75 is connected to an input port 82 opened and closed by the spool 79. selectively output port 83 which is communicated with to the input port 82 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 of the 2-3 shift valve 71, a port 86 that outputs a D range pressure at a speed higher than the third speed is connected to a port 85 that opens at a position where the spring 81 is disposed via an oil passage 87. Communication. In addition, 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 78 has a pressure adjustment level 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. Is configured to be large.

Further, reference numeral 89 in FIG. 4 denotes a 2-3 timing valve. The 2-3 timing valve 89 includes a spool 90 having a small-diameter land and two large-diameter lands, and a first plunger 91. It has a spring 92 disposed between them and a second plunger 93 disposed on the opposite side of the first plunger 91 with the spool 90 interposed therebetween.

An oil passage 95 is connected to an intermediate port 94 of the 2-3 timing valve 89, and the oil passage 95 is connected to the brake port 74 at the third or higher speed among the ports of the 2-3 shift valve 71. Is connected to a port 96 which communicates with the port.

油 Furthermore, the oil passage 95 branches on the way and is connected via an orifice to a port 97 opened between the small land and the large land. A port 98 selectively connected to the intermediate port 94 is connected to a solenoid relay valve 100 via an oil passage 99.

Then, the linear solenoid valve SLU is connected to the port that is open to an end portion of the first plunger 91, and the second brake B ₂ via an orifice to the port which is opened to the end of the second plunger 93 connected Have been.

The oil-passage 87 provided 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 104 having a check ball to open when the pressure discharged from the second brake B ₂ is interposed, explaining this oil passage 103 is below the orifice It is connected to the control valve 105.

Orifice control valve 105 is a valve for controlling the exhaust圧速degree from the second brake B _2, the second brake B ₂ is connected to a port 107 formed in an intermediate portion to be opened and closed by the spool 106 The oil passage 103 is connected to a port 108 formed below the port 107 in the figure.

A port 109 formed above the port 107 to which the second brake B ₂ is connected in the figure is a port selectively communicated with the drain port, and is connected to the port 109 via an oil passage 110. The port 111 of the B-3 control valve 78 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 the end of the port of the orifice control valve 105 opposite to the spring that presses the spool 106 is connected to a port 114 of the 3-4 shift valve 72 via an oil passage 113. The port 114 outputs a signal pressure of the third solenoid valve SL3 at a speed lower than the third speed, and outputs a signal pressure of the fourth solenoid valve SL4 at a speed higher than the fourth speed. is there.

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 that outputs the D range pressure at a speed lower than the second speed is connected to a port 117 that opens at a portion of the 2-3 timing valve 89 where a spring 92 is disposed. They are connected via an oil passage 118. Further, 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.

Then, in FIG. 4, reference numeral 121 denotes a second 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 of the engagement / release of the second brake B ₂ changes at a higher pressure as the signal pressure of the linear solenoid valve SLN is lower. Other clutch C _1, C ₂ and the brake B ₀ accumulator in such a gear change is provided by the accumulator control pressure is allowed to act, the transient hydraulic pressure at the time of shifting depending on the torque T _I of the input shaft 26 Is controlled.

Further, reference numeral 122 denotes a C-0 exhaust valve, and further reference numeral 123 denotes an accumulator for the clutch C _0. C-0 exhaust valve 122 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, B3 control if port 111 of the valve 78 if communicating with the drain, the engagement pressure P _B3 of the third brake B ₃ B3 Control - directly by Rubarubu 78 The pressure can be regulated, and the pressure regulation level can be changed by the linear solenoid valve SLU.

If the spool 106 of the orifice control valve 105 is located at the position shown in the left half of the figure, the second brake B ₂ can release the pressure through the orifice control valve 105, so that the second brake B ₂ Can control the drain speed.

Furthermore, shifting from the second gear position to the third gear position, but not so-called clutch-to-clutch shifting gently engages the second brake B ₂ together slowly releasing the third brake B ₃ is performed By controlling the transient hydraulic pressure P _B3 for releasing the third brake B ₃ driven by the linear solenoid valve SLU based on the input shaft torque T _I to the input shaft 26, the shift shock can be reduced appropriately. The control of the hydraulic pressure P _B3 based on the input shaft torque T _I can be performed in real time by feedback control or the like, but may be performed based only on the input shaft torque T _I at the start of shifting.

The hybrid drive device 10 includes a hybrid control controller 50 and an automatic transmission control controller 52 as shown in FIG. Each of these controllers 50 and 52 is provided with a microcomputer having a CPU, a RAM, a ROM, and the like, and receives an accelerator operation amount (an operation amount of an accelerator operation means such as an accelerator pedal) θ _AC from an accelerator operation amount sensor 62 and a brake switch. 64 from the brake ON, OFF, except that the signal representative of the catalyst temperature T _S of the exhaust pipe from the catalyst temperature sensor 66 are supplied, the input shaft rotational speed N _I of the automatic transmission 18, the output shaft rotation of the automatic transmission 18 Number N _O (corresponding to vehicle speed V), engine torque T _E , motor torque T _M , engine speed N _E , motor speed N _M , storage amount SOC of power storage device 58 (see FIG. 5), shift lever operation range And the like, and also performs signal processing according to a preset program.

The engine torque T _E is determined from a throttle valve opening and the fuel injection amount, the motor torque T _M is determined from a motor current, the electricity storage amount SOC is Ya motor current during charging motor generator 14 functions as a generator Required from charging efficiency.

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. Is supplied and is rotated by a predetermined torque, and a charging state in which regenerative braking (electric braking torque of motor generator 14 itself) functions as a generator to charge power storage device 58 with electric energy, The state is switched to a no-load state that allows the rotor shaft 14r to freely rotate.

The first clutch CE ₁ and the second clutch CE ₂ are switched between the engaged and disengaged states by the hybrid controller 50 switching the hydraulic circuit 40 via an electromagnetic valve or the like.

In the automatic transmission 18, the excitation state of the solenoid valves SL 1 to SL 4 and the linear solenoid valves SLU, SLT, SLN is controlled by the automatic transmission control controller 52, and the hydraulic circuit 40 is switched or hydraulic control is performed. The shift speed is switched according to a predetermined shift condition. The shift conditions are set, for example, 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.

For example, as described in Japanese Patent Application No. 7-294148 filed earlier by the present applicant, the hybrid control controller 50 performs one of the nine operation modes shown in FIG. 7 according to the flowchart shown in FIG. Then, the engine 12 and the electric torque converter 24 are operated in the selected mode.

In FIG. 6, in step S <b> 1, it is determined whether or not an engine start request has been issued, for example, in order to run the vehicle using 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. It is determined whether or not a command to start the motor 12 has been issued.

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 the engine 12 is started by performing engine start control such as fuel injection.

This mode 9 is performed with the automatic transmission 18 in neutral when the vehicle is stopped, and when the vehicle is running using only the motor generator 14 that has released the first clutch CE ₁ as a power source as in mode 1, the first clutch CE ₁ And by operating the motor generator 14 with an output higher than the required output required for traveling, and rotating the engine 12 with a margin output higher than the required output.

Also, even when the vehicle is running, it is possible to temporarily set the automatic transmission 18 in neutral to execute the mode 9. Since the engine 12 is started by the motor generator 14 in this manner, a starter (such as an electric motor) dedicated to starting is unnecessary, the number of parts is reduced, and the apparatus is inexpensive.

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 a braking force, for example, whether the brake is ON or not. The operating range of the lever is an engine brake range such as L or 2 (a range in which the shift control is performed only at the low speed shift stage and the engine brake and the regenerative braking are applied), and the accelerator operation amount θ _AC is 0 or not. It is determined by whether the accelerator operation amount θ _AC is 0 or not.

場合 If this judgment is affirmed, step S4 is executed. 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 S5 is performed. 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, for example, a value of about 80% based on the charge / discharge efficiency of the power storage device 58 and the like.

Mode 8 is selected in step S5, the first clutch CE _1, as shown in FIG. 7 engaged (ON), the second clutch CE ₂ engaged (ON), the no-load motor generator 14 In this state, 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 by the rubbing rotation and the pumping action of the engine 12, that is, the engine brake is applied to the vehicle. The braking operation by the driver is reduced, and the driving operation is facilitated. In addition, since motor generator 14 is set in a no-load state and is freely rotated, it is possible to prevent the state of charge and discharge efficiency and the like from being impaired due to excessive power storage amount SOC of power storage device 58.

Mode 6 is selected in step S6, disengaging the first clutch CE ₁ As is apparent from FIG. 7 (OFF), the second clutch CE ₂ engaged (ON), to stop the engine 12, the motor-generator When the motor generator 14 is driven to rotate by the kinetic energy of the vehicle, the power storage device 58 is charged and a regenerative braking force such as an engine brake is applied to the vehicle. And the driving operation is facilitated.

Further, since the first clutch CE ₁ are blocked is open the engine 12, since with no energy loss due to pulling rubbing of the engine 12, the electricity storage amount SOC is executed when less than the maximum storage amount B, The amount of charge SOC of the power storage device 58 does not become excessive and does not impair the performance such as charging and discharging efficiency.

On the other hand, if the determination in step S3 is denied, that is, if there is no request for the braking force, step S7 is executed, and whether the engine start is requested is determined by using the engine 12 as a power source, for example, in mode 3. The determination is made based on whether or not the running vehicle is stopped, that is, whether or not the vehicle speed V = 0.

If this determination is affirmed, step S8 is executed. In step S8, it is determined whether or not the accelerator is ON, that is, whether or not the accelerator operation amount θ _AC is larger than a predetermined value of substantially zero. If the accelerator is ON, mode 5 is selected in step S9, and if the accelerator is ON, If not, mode 7 is selected in step S10.

Mode 5 is selected by the step S9, the first clutch CE ₁ As apparent from FIG. 7 engaged (ON), the second clutch CE ₂ released (OFF), the engine 12 and operating conditions, The vehicle is started by controlling the regenerative braking torque of the motor generator 14.

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 order of 0.5 which is a common value of the gear ratio [rho _E, by half the torque of the engine torque T _E motor generator 14 is shared, approximately 1.5 times the torque of the engine torque T _E Output from the carrier 16c.

That is, a high torque start of (1 + ρ _E ) / ρ _E times the torque of motor generator 14 can be performed. Further, if the motor current is cut off and the motor generator 14 is set in the no-load state, the output from the carrier 16c becomes 0 only by rotating the rotor shaft 14r in the reverse direction, and the vehicle stops.

That is, the planetary gear device 16 in this case functions as a starting clutch and a torque amplifying device. The engine torque T _M is increased by gradually increasing the motor torque (regenerative braking torque) T _M from 0 to increase the reaction force. _The vehicle can be started smoothly with an output torque of (1 + ρ _E ) times _E.

Here, 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. It is small 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.

Mode 7 is selected in step S10, the first clutch CE ₁ As apparent from FIG. 7 engaged (ON), the second clutch CE ₂ released (OFF), the engine 12 and the operation state, the motor The generator 14 is set in a no-load state so as to be electrically neutral, and when the rotor shaft 14r of the motor generator 14 is freely rotated in the reverse direction, the output of the automatic transmission 18 to the input shaft 26 becomes zero. Accordingly, it is not necessary to stop the engine 12 one by one when the vehicle is stopped while the vehicle is 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 for starting the engine, step S11 is executed, and it is determined whether the required output Pd is equal to or less than a first determination value P1 set in advance. The required output Pd is an output necessary for the running of the vehicle including the running resistance, and is based on the accelerator operation amount θ _AC , its changing speed, the vehicle speed V (output shaft rotation speed N _O ), the gear position of the automatic transmission 18, and the like. , Calculated by a predetermined data map, an arithmetic expression, or the like. The first determination value P1 is a boundary value between a medium load region where the vehicle runs only with the engine 12 as a power source and a low load region where the vehicle runs only with the motor generator 14 as a power source. In the engine resonance region where the exhaust gas amount, the fuel consumption amount, and the like are reduced as much as possible, and the drive system resonates due to the vibration of the engine 12 and the NVH is deteriorated, only the motor generator 14 is used as a power source. Are determined in advance by experiments or the like.

If the determination in step S11 is affirmative, that is, if 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 a preset minimum state of charge A, and If ≧ A, mode 1 is selected in step S13. On the other hand, if SOC <A, 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.

The mode 1, the 7 As apparent from the first release clutch CE ₁ to (OFF), the second clutch CE ₂ engaged (ON), to stop the engine 12, required output of the motor generator 14 The motor is driven to rotate by Pd, and the vehicle runs using only the motor generator 14 as a power source.

In this case, since the engine 12 first clutch CE ₁ is released is interrupted, the mode 6 less similarly pulled rubbing losses, efficient motor drive by appropriate shift control of the automatic transmission 18 Control is possible.

Further, this mode 1 is executed when the required output Pd is in the low load region where the first determination value P1 or less and the state of charge SOC of the power storage device 58 is the minimum state of charge A or more. Energy efficiency is higher than when the vehicle is traveling, so that fuel consumption and exhaust gas can be reduced. In addition, the power storage amount SOC of the power storage device 58 does not drop below the minimum power storage amount A, and performance such as charge / discharge efficiency is not impaired.

Mode is selected at step S14 3 are both engaged (ON) apparent to the first clutch CE ₁ and the second clutch CE ₂ from FIG. 7, the engine 12 and the operation state, the regenerative braking of the motor-generator 14 The power storage device 58 is charged with electric energy generated by the motor generator 14 while the vehicle is running with the output of the engine 12. The engine 12 is operated at an output equal to or higher than the required output Pd, and the current control of the motor generator 14 is performed such 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 greater than the first determination value P1, in step S15, the required output Pd is greater than the first determination value P1 and less than the second determination value P2. It is determined whether or not P1 <Pd <P2.

The second determination value P2 is a boundary value between a medium 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 a power source. In consideration of the energy efficiency, the exhaust gas amount, the fuel consumption amount, and the like are determined in advance by experiments and the like so as to be as small as possible.

If P1 <Pd <P2, it is determined in step S16 whether SOC ≧ A. If SOC ≧ A, mode 2 is selected in step S17. If SOC <A, mode 2 is selected in step S14. Select mode 3. If Pd ≧ P2, it is determined whether or not SOC ≧ A in step S18. If SOC ≧ A, mode 4 is selected in step S19. If SOC <A, mode 2 is selected in step S17. select.

The mode 2, the 7 to clear the first clutch CE ₁ and the second clutch CE ₂ together engagement (ON) from operating the engine 12 at the required output Pd, the motor generator 14 no-load condition The vehicle is run using only the engine 12 as a power source.

In the 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 driven at high output using both power sources.

This 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. However, since the engine 12 and the motor generator 14 are used together, only one of the engine 12 and the motor generator 14 is used. Compared to traveling as a power source, energy efficiency is not significantly impaired, and fuel consumption and exhaust gas can be reduced. In addition, since the process is executed when the state of charge SOC is equal to or more than the minimum state of charge A, the state of charge SOC of the power storage device 58 does not drop below the minimum state of charge A and does not impair the performance such as charge and discharge efficiency.

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 travels using only the motor generator 14 as a power source. In the medium load region of <Pd <P2, the mode 2 is selected in step S17 and the vehicle runs using only the engine 12 as a power source. In the high load region of P2 ≦ Pd, the mode 4 is selected in step S19 and the engine 12 and the motor generator are selected. The vehicle runs using both of the power sources 14 as power sources.

FIG. 9 is a mode switching map substantially equivalent to the switching conditions of the operation modes 1, 2, and 4, in which the accelerator operation amount θ _AC and the vehicle speed V are set as parameters, and the required output Pd is obtained. Instead, mode switching may be performed according to the mode switching map. The mode 1 area corresponds to the motor running area, the mode 2 area corresponds to the engine running area, and the mode 4 area corresponds to the engine + motor running area.

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

Mode 2 of step S17 is executed in the medium load region of P1 <Pd <P2 and when SOC ≧ A, or in the high load region of Pd ≧ P2 and when SOC <A. Since the energy efficiency of the engine 12 is higher than that of the motor generator 14, 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 region, mode 4 in which the motor generator 14 and the engine 12 are used together is desirable. However, when the state of charge SOC of the power storage device 58 is smaller than the minimum state of charge A, only the engine 12 in mode 2 is used. Is performed, power storage SOC of power storage device 58 is less than minimum power storage A and loss of performance such as charge / discharge efficiency is avoided.

On the other hand, the hybrid control controller 50 performs signal processing according to the flowchart of FIG. 8 prior to the mode switching control of FIG. 6 during predetermined deceleration running, and performs fuel cut control of the engine 12, regeneration control of the motor generator 14, first clutch CE ₁ engaging performs release control. Steps SA1 to SA3 in FIG. 8 correspond to deceleration traveling determination means, step SA4 corresponds to fuel supply stopping means, step SA9 corresponds to braking force supplementing means, and step SA10 corresponds to engine disconnection means.

In FIG. 8, in step SA1, it is determined based on a signal supplied from the accelerator operation amount sensor 62 whether or not an accelerator off time T _AC indicating a time during which the accelerator pedal is not depressed is equal to or longer than a predetermined time α. You. If this determination is denied, it is determined in step SA2 whether or not the accelerator operation amount θ _AC is approximately 0 at the present time based on the signal supplied from the accelerator operation amount sensor 62. If this determination is affirmed, it is determined in step SA3 whether the rate of change ΔV of the vehicle speed V is smaller than a predetermined value −β, in other words, whether or not the vehicle is in a predetermined deceleration state.

If the determination in step SA1 is affirmative, or if the determination in step SA3 is affirmative, fuel supply to the engine 12 is stopped in step SA4 (fuel cut control). In step SA5, the regenerative braking torque of motor generator 14 is controlled, a predetermined regenerative braking force is applied to the vehicle, and power storage device 58 is charged in accordance with the braking force. This regenerative braking is different from the mode 6 of FIG. 7, in this stage is carried out while keeping the first clutch CE ₁ the engagement (ON) state. Incidentally, the second clutch CE ₂ is engaged (ON) state.

Next, in step SA6, it is determined whether a brake ON signal is supplied from the brake switch 64. If this determination is affirmative, in step SA7, the catalyst temperature sensor 66 determines whether or not the catalyst temperature T _S in the exhaust pipe is equal to or higher than a predetermined value γ. The predetermined value γ is set to a temperature at which the generation of exhaust gas such as NO _X and CO becomes a problem when the engine 12 is stopped and restarted.

If the determination in step SA7 is affirmative, in step SA8 it is determined whether or not the vehicle is in an operating region in which the vehicle runs with the motor generator 14 as a power source, in accordance with the operation mode determination subroutine of FIG. Alternatively, the determination is made based on whether or not the vehicle is in the operation region of mode 1 or 4 in FIG. If the judgment is negative, that is, when the operating range for running only the engine 12 as a power source, a first clutch CE ₁ is maintained in the engaged (ON) condition, forced rotation engine 12 in accordance with the vehicle speed Let me do.

On the other hand, if the determination in step SA8 is affirmative, in step SA9, the regenerative torque of the motor generator 14 is controlled to compensate for the disappearance of the engine braking force due to the disconnection of the engine 12 in step SA10. The braking force by regeneration is increased by an amount corresponding to the force. Subsequently, in step SA10 first clutch CE ₁ is released (OFF), the engine 12 is rotating is stopped is disconnected from the planetary gear unit 16. Regenerative torque control in step SA9, it is desirable to perform in correspondence with the reduction in the engine braking force by the first release control of the clutch CE ₁ step SA10.

According to the present embodiment, as described above, the fuel supply to the engine 12 is stopped during the deceleration running that does not require the engine torque in step SA4 corresponding to the fuel supply stopping means, so that the fuel efficiency is improved.

Further, when the fuel supply to the engine 12 is stopped, becomes NO determination in step SA8, the first clutch CE ₁ engagement (ON) state is maintained in the operating region running only the engine 12 as a power source Since the engine 12 is forcibly rotated as the vehicle travels, at the time of re-acceleration when the accelerator pedal is depressed, the engine output is rapidly increased with fuel supply, and the driver's intention is increased. Even if the driving force is quickly obtained, there is no danger of rattling.

On the other hand, in the operation region where traveling motor generator 14 as a power source, the determination of step SA8 first clutch CE ₁ is released in step SA10 is YES, and although the engine 12 is caused disconnected rotation stopped by reacceleration At times, by increasing the output of the motor generator 14, the driving force intended by the driver can be promptly obtained, so that there is no danger of a backlash. In the engine + motor traveling region of mode 4, the motor torque is controlled to be relatively large in anticipation of the start delay of the engine 12 at the time of re-acceleration.

Further, if the engine 12 is disconnected when the brake is ON in the determination of step SA6 is YES, the engine braking force due to the rubbing rotation and the pumping action cannot be obtained. However, in the present embodiment, in step SA9, this corresponds to the engine braking force. Since the regenerative torque of the motor generator 14 is increased by the amount, the braking force does not change and the driver does not feel uncomfortable, and the power storage device 58 is charged by the regenerative braking, so that the fuel efficiency is further improved. .

Further, if the engine 12 is separated and stopped when the catalyst temperature T _S is low, the generation of exhaust gas such as NO _X and CO becomes a problem when the engine 12 is started next time. _{When S} is lower than the predetermined value γ, the determination in step SA7 is NO, and the disconnection of the engine 12 is prohibited. Therefore, such a problem of the exhaust gas when the engine 12 is restarted is avoided.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention is applicable to other embodiments.

For example, in the above-described embodiment, the automatic transmission 18 having one reverse speed and five forward speeds is used. However, as shown in FIG. It is also possible to adopt an automatic transmission 60 composed of only the main transmission 22, and to perform shift control at four forward speeds and one reverse speed as shown in FIG. Note that the present invention can be applied to a hybrid vehicle without a transmission.

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

1 is a skeleton diagram illustrating a configuration of a hybrid drive device of a hybrid vehicle including a drive control device according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a control system provided in the hybrid drive device of FIG. 1. FIG. 2 is a diagram illustrating an operation of an engagement element that establishes each shift speed of the automatic transmission in FIG. 1. FIG. 2 is a diagram illustrating a part of a hydraulic circuit of the automatic transmission of FIG. 1. FIG. 3 is a diagram illustrating a connection relationship between the hybrid control controller of FIG. 2 and an electric torque converter. 2 is a flowchart illustrating a basic operation of the hybrid drive device of FIG. 1. FIG. 7 is a diagram illustrating the operation states of modes 1 to 9 in the flowchart of FIG. 6. 4 is a flowchart illustrating a main part of a control operation that is a feature of the present invention. FIG. 4 is a diagram illustrating a map in which an accelerator operation amount and a vehicle speed used for switching a power source according to driving conditions are set in advance as parameters. FIG. 2 is a skeleton view illustrating a configuration of a hybrid drive device including an automatic transmission different from the embodiment of FIG. 1. FIG. 11 is a diagram illustrating an operation of an engagement element that establishes each shift speed of the automatic transmission in FIG. 10.

Explanation of reference numerals

12: Engine 14: motor generator (electric motor) 18,60: automatic transmission 50: hybrid control controller 58: power storage device CE _1: first clutch (clutch means)
Step SA4: Fuel supply stopping means Step SA9: Braking force supplementing means Step SA10: Engine disconnecting means

Claims (14)

An engine that operates by burning fuel and an electric motor that operates with electric energy are provided as power sources when the vehicle travels, and the operating states of the engine and the electric motor vary depending on operating conditions in a plurality of operation modes. In a traveling hybrid vehicle,
Clutch means for disconnecting the engine from the electric motor;
Engine disconnecting means for releasing the clutch means when the brake is ON to disconnect the engine from the electric motor;
Braking force supplementing means for supplementing a braking force corresponding to an engine braking force with regenerative braking when the engine is separated by the engine separating means;
A drive control device for a hybrid vehicle, comprising: 2. The hybrid vehicle according to claim 1, wherein the engine disconnecting unit releases the clutch unit and disconnects the engine on condition that fuel supply to the engine is stopped during deceleration running. 3. Drive control device. The drive control device for a hybrid vehicle according to claim 1, wherein the engine disconnecting unit releases the clutch unit and disconnects the engine on condition that a catalyst temperature is equal to or higher than a predetermined value. 2. The drive control of a hybrid vehicle according to claim 1, wherein the engine disconnecting unit releases the clutch unit and disconnects the engine on condition that the driving range is a driving range in which the electric motor is used as a power source. 3. apparatus. An engine that operates by burning fuel and an electric motor that operates with electric energy are provided as power sources when the vehicle travels, and the operating states of the engine and the electric motor vary depending on operating conditions in a plurality of operation modes. In a traveling hybrid vehicle,
Clutch means for disconnecting the engine from the electric motor;
Engine disconnecting means for releasing the clutch means during deceleration traveling to disconnect the engine from the electric motor;
Braking force supplementing means for supplementing a braking force corresponding to an engine braking force with regenerative braking when the engine is separated by the engine separating means;
A drive control device for a hybrid vehicle, comprising: The drive control device for a hybrid vehicle according to claim 5, wherein the engine disconnecting unit releases the clutch unit and disconnects the engine on condition that fuel supply to the engine is stopped. The drive control device for a hybrid vehicle according to claim 5, wherein the engine disconnecting means releases the clutch means and disconnects the engine on condition that a catalyst temperature is equal to or higher than a predetermined value. The drive control of a hybrid vehicle according to claim 5, wherein the engine disconnecting means releases the clutch means and disconnects the engine on condition that the driving area is a driving range in which the electric motor runs as a power source. apparatus. An engine that operates by burning fuel and an electric motor that operates with electric energy are provided as power sources when the vehicle travels, and the operating states of the engine and the electric motor vary depending on operating conditions in a plurality of operation modes. In a traveling hybrid vehicle,
Fuel supply stopping means for stopping fuel supply to the engine;
Engine disconnecting means for releasing clutch means to disconnect the engine;
A drive control device for a hybrid vehicle, comprising: during deceleration running, disconnecting the engine by the engine disconnecting means, and stopping fuel supply to the engine by the fuel supply stopping means. The drive control device for a hybrid vehicle according to claim 9, wherein the engine disconnecting means releases the clutch means and disconnects the engine on condition that the brake is ON. The drive control device for a hybrid vehicle according to claim 9, wherein the engine disconnecting means releases the clutch means and disconnects the engine on condition that a catalyst temperature is equal to or higher than a predetermined value. The drive control of a hybrid vehicle according to claim 9, wherein the engine disconnecting means releases the clutch means and disconnects the engine on condition that the operating area is a driving range in which the electric motor runs as a power source. apparatus. The drive control device for a hybrid vehicle according to claim 9, further comprising a power storage device that supplies electric energy to the electric motor. The drive control device for a hybrid vehicle according to any one of claims 1 to 13, wherein an automatic transmission is disposed between the engine and the electric motor and the drive wheels.

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