HYBRID VEHICLE AND CONTROL METHOD THEREOF

• US 20090306843A1
• Filed: 12/14/2007
• Published: 12/10/2009
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yaguchi, Hideakl, Maeda, Masahiko, Jinno, Kunihiko, Nakagawa, Tadashi
• Granted Patent: US 8,271,156 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• CPC Class Codes: B60K 6/00 Arrangement or mounting of plural diverse prime-movers for mutual or common propulsion, e.g. hybrid propulsion systems comprising electric motors and internal combustion engines ; Control systems therefor, i.e. systems controlling two or more prime movers, or controlling one of these prime movers and any of the transmission, drive or drive units arrangement or mounting in vehicles of electrical gearing, in which an electrical machine serves only as reduction gearing and not as the prime mover and in which no electrical storing means are used B60K17/12; control and regulation of purely electrical prime movers B60L; prime-movers comprising electrical and internal combustion motors in a common engine block or housing per se F02B65/00; electric motors or motor-generators used for starting the combustion engine F02N11/04; electric motors for synchronising gearing F16H3/12 Informative references: mechanical gearings with secondary electric drive F16H3/72; arrangements for handling mechanical energy structurally associated with the dynamo-electric machine H02K7/00; machines comprising structurally interrelated motor and generator parts H02K51/00; dynamo-electric machines not otherwise provided for in H02K see H02K99/00
• CPC Class Codes: B60K 6/44 Series-parallel type
• 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: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2220/52 Clutch motors
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 2250/24 by lever actuation
• CPC Class Codes: B60L 2250/26 : by pedal actuation
• CPC Class Codes: B60L 2260/28 : Four wheel or all wheel drive
• CPC Class Codes: B60L 2270/145 : Structure borne vibrations
• 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: B60L 58/12 : responding to state of charge [SoC]
• CPC Class Codes: B60L 58/20 : having different nominal voltages
• CPC Class Codes: B60L 7/14 : for vehicles propelled by ac motors
• CPC Class Codes: B60W 10/04 : including control of propulsion units
• 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 20/40 : Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2540/215 : Selection or confirmation of options
• CPC Class Codes: B60W 2710/086 : Power
• CPC Class Codes: B60W 50/082 : Selecting or switching between different modes of propelling
• CPC Class Codes: B60W 50/085 : Changing the parameters of the control units, e.g. changing limit values, working points by control input
• CPC Class Codes: F02D 29/00 : Controlling engines, such controlling being peculiar to the devices driven thereby, the devices being other than parts or accessories essential to engine operation, e.g. controlling of engines by signals external thereto
• CPC Class Codes: F02D 29/02 : peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• 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
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 10/84 : Data processing systems or methods, management, administration

Abstract

When determined that a driver'"'"'s accelerator operation is rough during the turn-on condition of an ECO switch 88 while a hybrid vehicle 20 is driven without an operation of an engine 22 (Step S120), a threshold value Pref with respect to a power demand P* is set to a value P2 that is larger than a value P1 of the turn-off condition of the ECO switch 88 so as to give priority to fuel consumption of the engine 22 (Step S140). Then, the engine 22, motors MG1 and MG2 are controlled with a start of the engine 22 as necessary so as to ensure torque equivalent to a torque demand Tr* (Steps S150-S230).

Claims

1. A hybrid vehicle comprising:

an internal combustion engine capable of outputting power for driving the vehicle;

a motor capable of outputting power for driving the vehicle;

an accumulator capable of supplying electric power to the motor;

a fuel consumption priority mode selection switch to select a fuel consumption priority mode that gives priority to fuel consumption;

an engine start condition setting module configured to set a start condition of the internal combustion engine to a first condition when the fuel consumption priority mode selection switch is turned off during a driving without an operation of the internal combustion engine, the engine start condition setting module setting the start condition of the internal combustion engine to a second condition giving priority to fuel consumption in comparison with the first condition when the fuel consumption priority mode selection switch is turned on during the driving without the operation of the internal combustion engine;

a driving force demand setting module configured to set a driving force demand required for driving the vehicle; and

an engine stop driving control module configured to control the internal combustion engine and the motor so that a driving power equivalent to the set driving force demand is ensured without a start of the internal combustion engine when the set start condition is not satisfied during the driving without the operation of the internal combustion engine, the engine stop driving control module controlling the internal combustion engine and the motor so that the driving power equivalent to the set driving force demand is ensured with the start of the internal combustion engine when the set start condition is satisfied during the driving without the operation of the internal combustion engine.

2. A hybrid vehicle according to claim 1, wherein the second condition has a tendency to permit the stop of the internal combustion engine to continue in comparison with the first condition.

3. A hybrid vehicle according to claim 1, wherein the first and second conditions are respectively satisfied when the set driving force demand is equal to or more than a predetermined threshold, and wherein the threshold in the second condition is larger than that in the first condition.

4. A hybrid vehicle according to claim 1, further comprising:

an accelerator operation amount detecting unit configured to detect an accelerator operation amount by a driver; and

an accelerator operation determination module configured to determine whether or not a driver'"'"'s accelerator operation is rough in accordance with the detected accelerator operation amount;

wherein the engine start condition setting module sets the start condition to the first condition when the accelerator operation determination unit determines that the driver'"'"'s accelerator operation is not rough and the fuel consumption priority mode selection switch is turned on during the driving without the operation of the internal combustion engine, and wherein the engine start condition setting module sets the start condition to the second condition when the accelerator operation determination unit determines that the driver'"'"'s accelerator operation is rough and the fuel consumption priority mode selection switch is turned on during the driving without the operation of the internal combustion engine.

5. A hybrid vehicle according to claim 1, further comprising:

a power transmitting mechanism having an axle-side rotational element connected to a predetermined axle, and an engine-side rotational element connected to an engine shaft of the internal combustion engine and configured to differentially rotate with respect to the axle-side rotational element, the power transmitting mechanism capable of outputting at least a part of power from the engine shaft to the axle side.

6. A hybrid vehicle according to claim 5, wherein the power transmitting mechanism is an electric power-mechanical power input output structure connected to the predetermined axle and the engine shaft of the internal combustion engine and outputting at least a part of power from the internal combustion engine to the axle side with input/output of electric power and mechanical power, the electric power-mechanical power input output structure supplying and receiving electric power from the accumulator.

7. A hybrid vehicle according to claim 6, wherein the electric power-mechanical power input output structure includes a power generation motor capable of inputting and outputting power, and a three shaft-type power input output assembly connected with three shafts, the predetermined axle, the engine shaft of the internal combustion engine, and a rotating shaft of the power generation motor, the three shaft-type power input output assembly configured to input and output power to one remaining shaft, based on input and output of powers from and to any two shafts selected among the three shafts, and wherein the motor is capable of outputting power to the predetermined axle or another axle different from the predetermined axle.

8. A hybrid vehicle according to claim 5, wherein the power transmitting mechanism is a continuously variable transmission.

9. A control method of a hybrid vehicle including an internal combustion engine capable of outputting power for driving the vehicle, a motor capable of outputting power for driving the vehicle, an accumulator capable of supplying electric power to the motor and a fuel consumption priority mode selection switch to select a fuel consumption priority mode that gives priority to fuel consumption, the method comprising the steps of:

(a) setting a start condition of the internal combustion engine to a first condition when the fuel consumption priority mode selection switch is turned off during a driving without an operation of the internal combustion engine, and setting the start condition of the internal combustion engine to a second condition giving priority to fuel consumption in comparison with the first condition when the fuel consumption priority mode selection switch is turned on during the driving without the operation of the internal combustion engine; and

(b) controlling the internal combustion engine and the motor so that a driving power equivalent to a driving force demand required for driving the vehicle is ensured without a start of the internal combustion engine when the set start condition is not satisfied during the driving without the operation of the internal combustion engine, and controlling the internal combustion engine and the motor so that the driving power equivalent to the driving force demand is ensured with the start of the internal combustion engine when the set start condition is satisfied during the driving without the operation of the internal combustion engine.

10. A control method of a hybrid vehicle according to claim 9, wherein the second condition used at the step (a) has a tendency to permit the stop of the internal combustion engine to continue in comparison with the first condition.

11. A control method of a hybrid vehicle according to claim 9, wherein the first and second conditions used at the step (a) are respectively satisfied when the driving force demand is equal to or more than a predetermined threshold, and wherein the threshold in the second condition is larger than that in the first condition.

12. A control method of a hybrid vehicle according to claim 9, further comprising the step of:

(c) determining whether or not a driver'"'"'s accelerator operation is rough in accordance with an accelerator operation amount by the driver;

wherein the step (b) sets the start condition to the first condition when the step (c) determines that the driver'"'"'s accelerator operation is not rough and the fuel consumption priority mode selection switch is turned on during the driving without the operation of the internal combustion engine, and wherein the step (b) sets the start condition to the second condition when the step (c) determines that the driver'"'"'s accelerator operation is rough and the fuel consumption priority mode selection switch is turned on during the driving without the operation of the internal combustion engine.

13. A hybrid vehicle comprising:

an internal combustion engine capable of outputting power for driving the vehicle;

a motor capable of outputting power for driving the vehicle;

an accumulator capable of supplying electric power to the motor;

a mode selection switch to select a mode having tendency to make the internal combustion engine hard to start in comparison with a normal state;

an engine start condition setting module configured to set a start condition of the internal combustion engine to a first condition when the mode selection switch is turned off during a driving without an operation of the internal combustion engine, the engine start condition setting module setting the start condition of the internal combustion engine to a second condition having tendency to make the internal combustion engine hard to start in comparison with the first condition when the mode selection switch is turned on during the driving without the operation of the internal combustion engine;

a driving force demand setting module configured to set a driving force demand required for driving the vehicle; and

an engine stop driving control module configured to control the internal combustion engine and the motor so that a driving power equivalent to the set driving force demand is ensured without a start of the internal combustion engine when the set engine start condition is not satisfied during the driving without the operation of the internal combustion engine, the engine stop driving control module controlling the internal combustion engine and the motor so that the driving power equivalent to the set driving force demand is ensured with the start of the internal combustion engine when the set engine start condition is satisfied during the driving without the operation of the internal combustion engine.

14. A control method of a hybrid vehicle including an internal combustion engine capable of outputting power for driving the vehicle, a motor capable of outputting power for driving the vehicle, an accumulator capable of supplying electric power to the motor, and a mode selection switch to select a mode having tendency to make the internal combustion engine hard to start in comparison with a normal state, the method comprising the steps of:

(a) setting a start condition of the internal combustion engine to a first condition when the mode selection switch is turned off during a driving without an operation of the internal combustion engine, and setting the start condition of the internal combustion engine to a second condition having tendency to make the internal combustion engine hard to start in comparison with the first condition when the mode selection switch is turned on during the driving without the operation of the internal combustion engine; and

(b) controlling the internal combustion engine and the motor so that a driving power equivalent to a driving force demand required for driving the vehicle is ensured without a start of the internal combustion engine when the set start condition is not satisfied during the driving without the operation of the internal combustion engine, and controlling the internal combustion engine and the motor so that the driving power equivalent to the driving force demand is ensured with the start of the internal combustion engine when the set start condition is satisfied during the driving without the operation of the internal combustion engine.