Power output apparatus, control method of power output apparatus, and vehicle equipped with power output apparatus

• US 7,587,269 B2
• Filed: 08/25/2006
• Issued: 09/08/2009
• Est. Priority Date: 08/25/2005
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kimura, Akihiro, Ando, Daigo, Kamichi, Kensuke, Muta, Koichiro
• Primary Examiner(s): KWON, JOHN
• Application Number:
  US11/989,393
• Publication Number:
  US 20090105924A1
• Time in Patent Office: 1,110 Days
• Field of Search: 701/101, 701/112, 701/110, 701/114, 701/99
• US Class Current: 701/110
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/40 characterised by the assembly or relative disposition of components
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/448 Electrical distribution type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 20/16 for reducing engine exhaust emissions
• CPC Class Codes: F01N 11/002 the diagnostic devices measuring or estimating temperature or pressure in, or downstream of the exhaust apparatus
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: F02D 41/0235 in relation with the state of the exhaust gas treating apparatus control of exhaust gas treating apparatus per se F01N
• CPC Class Codes: F02D 41/12 for deceleration F02D41/0005, F02D41/107 take precedence
• CPC Class Codes: F02D 41/123 the fuel injection being cut-off
• CPC Class Codes: F16H 2037/0866 Power split variators with distributing differentials, with the output of the CVT connected or connectable to the output shaft
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

In response to the driver'"'"'s depression of a brake pedal in requirement of catalyst deterioration control with a catalyst deterioration control flag Fc set equal to 1, the braking control of the invention controls the operation of a motor to make a rotation speed Ne of an engine approach to a target rotation speed Ne* in a state of continued combustion (firing) of the engine (steps S180 and S190). Such control ensures a quick decrease of the rotation speed Ne of the engine to the target rotation speed Ne*, thus effectively reducing the wasteful fuel consumption due to the continued operation of the engine at a high rotation speed and enhancing the overall energy efficiency of the vehicle.

Claims

1. A power output apparatus that outputs power to a driveshaft, the power output apparatus comprising:

an internal combustion engine;

an electric power-mechanical power input output structure that is connected to an output shaft of the internal combustion engine and to the driveshaft and outputs at least part of output power of the internal combustion engine to the driveshaft through input and output of electric power and mechanical power;

a motor that inputs and outputs power to and from the driveshaft;

an accumulator unit that transmits electric power from and to the electric power-mechanical power input output structure and the motor;

a driving force demand setting module that sets a driving force demand to be output to the driveshaft;

a target operating condition setting module that, upon failure of a continued combustion condition of continuing combustion in the internal combustion engine, sets a target operating condition of the internal combustion engine including an intermittent operation of the internal combustion engine based on the set driving force demand, while upon satisfaction of the continued combustion condition, continuing operation of the internal combustion engine and setting the target operating condition of the internal combustion engine based on the set driving force demand; and

a control module that, in a state other than a specific driving state of applying a braking force or a small load to the driveshaft upon satisfaction of the continued combustion condition, performs continued medium-high load combustion control which controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to drive the internal combustion engine in the set target operating condition and to ensure output of a driving force equivalent to the set driving force demand to the driveshaft,

in the specific driving state, the control module performing continued low load combustion control which controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to drive the internal combustion engine in the set target operating condition with continued combustion in the internal combustion engine and to ensure output of a driving force equivalent to the set driving force demand to the driveshaft.

2. The power output apparatus in accordance with claim 1, wherein in the specific driving state, the target operating condition setting module sets the target operating condition of the internal combustion engine to a preset driving condition of attaining self-sustained operation of the internal combustion engine at a preset rotation speed.

3. The power output apparatus in accordance with claim 1, wherein in the specific driving state, the control module controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to change an operating condition of the internal combustion engine in a range of allowing continued combustion of the internal combustion engine and thereby make the operating condition of the internal combustion engine approach to the set target operating condition.

4. The power output apparatus in accordance with claim 3, wherein in the specific driving state, the control module controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to change the operating condition of the internal combustion engine to the set target operating condition by a preset rotation speed per unit time.

5. The power output apparatus in accordance with claim 1, the power output apparatus further having:

an input limit setting module that sets an input limit of the accumulator unit as a maximum power level of allowing charge of the accumulator unit, based on a state of the accumulator unit,

wherein the control module controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor in a range of the set input limit of the accumulator unit.

6. The power output apparatus in accordance with claim 5, the power output apparatus further having:

a charge-discharge electric power detector that measures a charge-discharge electric power of charging the accumulator unit or being discharged from the accumulator unit,

wherein when execution of the continued low load combustion control to limit the measured charge-discharge electric power in the range of the set input limit of the accumulator unit in the specific driving state makes it impossible to drive the internal combustion engine in the set target operating condition, the control module performs fuel cutoff control of stopping fuel injection in the internal combustion engine to enable the internal combustion engine to be driven in the target operating condition.

7. The power output apparatus in accordance with claim 6, wherein the control module controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to change a rotation speed of the internal combustion engine by a preset rotation speed per unit time in the course of the fuel cutoff control of stopping fuel injection in the internal combustion engine to enable the internal combustion engine to be driven in the target operating condition.

8. The power output apparatus in accordance with claim 1, wherein the internal combustion engine is equipped with an emission control device that uses a catalyst for exhaust emission control, and

the continued combustion condition is a condition of performing catalyst deterioration control to restrict deterioration of the catalyst used in the emission control device.

9. The power output apparatus in accordance with claim 1, wherein the electric power-mechanical power input output structure has:

a three shaft-type power input output mechanism that is linked to three shafts, the output shaft of the internal combustion engine, the driveshaft, and a rotating shaft, and inputs and outputs power from and to a residual one shaft based on powers input from and output to any two shafts among the three shafts; and

a generator that inputs and outputs power from and to the rotating shaft.

10. A vehicle, comprising:

an internal combustion engine;

an electric power-mechanical power input output structure that is connected to an output shaft of the internal combustion engine and to a driveshaft linked to an axle and outputs at least part of output power of the internal combustion engine to the driveshaft through input and output of electric power and mechanical power;

a motor that inputs and outputs power to and from the driveshaft;

an accumulator unit that transmits electric power from and to the electric power-mechanical power input output structure and the motor;

a driving force demand setting module that sets a driving force demand to be output to the driveshaft;

a target operating condition setting module that, upon failure of a continued combustion condition of continuing combustion in the internal combustion engine, sets a target operating condition of the internal combustion engine including an intermittent operation of the internal combustion engine based on the set driving force demand, while upon satisfaction of the continued combustion condition, continuing operation of the internal combustion engine and setting the target operating condition of the internal combustion engine based on the set driving force demand; and

a control module that, in a state other than a specific driving state of applying a braking force or a small load to the driveshaft upon satisfaction of the continued combustion condition, performs continued medium-high load combustion control which controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to drive the internal combustion engine in the set target operating condition and to ensure output of a driving force equivalent to the set driving force demand to the driveshaft,

in the specific driving state, the control module performing continued low load combustion control which controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to drive the internal combustion engine in the set target operating condition with continued combustion in the internal combustion engine and to ensure output of a driving force equivalent to the set driving force demand to the driveshaft.

11. A control method of a power output apparatus, the power output apparatus having:

an internal combustion engine;

an electric power-mechanical power input output structure that is connected to an output shaft of the internal combustion engine and to the driveshaft and outputs at least part of output power of the internal combustion engine to the driveshaft through input and output of electric power and mechanical power;

a motor that inputs and outputs power to and from the driveshaft; and

an accumulator unit that transmits electric power from and to the electric power-mechanical power input output structure and the motor,

the control method of the power output apparatus comprising the steps of;

(a) upon failure of a continued combustion condition of continuing combustion in the internal combustion engine, setting a target operating condition of the internal combustion engine including an intermittent operation of the internal combustion engine based on a driving force demand that is to be output to the driveshaft, while upon satisfaction of the continued combustion condition, continuing operation of the internal combustion engine and setting the target operating condition of the internal combustion engine based on the driving force demand; and

(b) in a state other than a specific driving state of applying a braking force or a small load to the driveshaft upon satisfaction of the continued combustion condition, performing continued medium-high load combustion control which controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to drive the internal combustion engine in the set target operating condition and to ensure output of a driving force equivalent to the driving force demand to the driveshaft,

in the specific driving state, performing continued low load combustion control which controls the internal combustion engine, the electric power-mechanical power input output structure, and the motor to drive the internal combustion engine in the set target operating condition with continued combustion in the internal combustion engine and to ensure output of a driving force equivalent to the driving force demand to the driveshaft.

12. The control method of the power output apparatus in accordance with claim 11, wherein when execution of the continued low load combustion control to limit a charge-discharge electric power of charging the accumulator unit or being discharged from the accumulator unit in the range of an input limit of the accumulator unit in the specific driving state makes it impossible to drive the internal combustion engine in the set target operating condition, the step (b) performs fuel cutoff control of stopping fuel injection in the internal combustion engine to enable the internal combustion engine to be driven in the target operating condition.