Hybrid vehicle and control method of hybrid vehicle

• US 7,610,974 B2
• Filed: 01/30/2006
• Issued: 11/03/2009
• Est. Priority Date: 01/31/2005
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Abe, Tetsuya
• Primary Examiner(s): PHAN, HAU VAN
• Application Number:
  US11/792,694
• Publication Number:
  US 20080105477A1
• Time in Patent Office: 1,373 Days
• Field of Search: 180/65.2, 180/65.3, 180/65.4, 180/65.6, 180/65.8, 180/65.21, 180/65.225, 180/65.265, 180/65.27, 180/65.28, 180/65.285, 903/903, 903/905, 903/907, 477/46, 477/5, 477/3, 477/94, 701/22, 701/102, 701/84
• US Class Current: 180/65.21
• 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 6/445 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 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 58/15 Preventing overcharging
• 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 10/18 including control of braking systems
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2510/081 Speed
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2540/16 Ratio selector position
• CPC Class Codes: B60W 2710/0605 : Throttle position
• CPC Class Codes: B60W 2710/0644 : Engine speed
• CPC Class Codes: B60W 2710/081 : Speed
• CPC Class Codes: F02D 13/04 : using engine as brake
• CPC Class Codes: F02D 29/02 : peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• 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 10/62 : 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: Y10S 903/903 : having energy storing means, e.g. battery, capacitor

Abstract

In a hybrid vehicle where an engine, a first motor, and a driveshaft are all connected to a planetary gear mechanism and the driveshaft is further linked to a second motor, when a battery is in an unchargeable state in the release of both an accelerator and a brake (step S130), a throttle opening TH* and a valve timing VVT* for air intake and exhaust are set to increase a pumping loss of the engine with an increase in absolute value of a braking power demand, which is to be output to the driveshaft (step S170). The engine is controlled with the throttle opening TH* and the valve timing VVT*, while the second motor is under regenerative control to generate electric power. The first motor used for motoring of the engine is then controlled to consume the electric power generated by the regenerative control of the second motor.

Claims

1. A hybrid vehicle, comprising:

an internal combustion engine that is rotatable independently of a driving state of said hybrid vehicle;

a rotational resistance adjustment structure that adjusts a rotational resistance of the internal combustion engine;

an engine-starting motor that is driven for motoring of the internal combustion engine;

an accumulator unit that is chargeable and dischargeable;

a driving motor that has power generation capability and inputs and outputs driving power through transmission of electric power to and from at least one of the engine-starting motor and the accumulator unit; and

an accelerator-brake-released state control module that, when the accumulator unit is in an unchargeable state at a timing of a braking force demand by release of both an accelerator and a brake, controls the rotational resistance adjustment structure to adjust the rotational resistance of the internal combustion engine according to the braking force demand, controls the driving motor to drive said hybrid vehicle with a braking force equivalent to the braking force demand and to generate regenerative electric power, and controls the engine-starting motor to consume the regenerative electric power generated by the driving motor by having the engine-starting motor operate to motor the internal combustion engine.

2. A hybrid vehicle in accordance with claim 1, wherein the rotational resistance adjustment structure regulates a throttle opening to adjust the rotational resistance of the internal combustion engine.

3. A hybrid vehicle in accordance with claim 1, wherein the rotational resistance adjustment structure regulates an air intake-exhaust timing to adjust the rotational resistance of the internal combustion engine.

4. A hybrid vehicle in accordance with claim 1, wherein when the accumulator unit is in the unchargeable state at the timing of the braking force demand, the accelerator-brake-released state control module controls the rotational resistance adjustment structure to increase the rotational resistance of the internal combustion engine with an increase in braking force demand.

5. A hybrid vehicle in accordance with claim 1, said hybrid vehicle further comprising:

a gearshift position setting module that, in response to a driver'"'"'s operation, selects and sets one gearshift position among multiple available gearshift positions, which require multiple different levels of braking force in the release of the accelerator and the brake,

wherein when the accumulator unit is in the unchargeable state at the timing of the braking force demand, said accelerator-brake-released state control module controls the rotational resistance adjustment structure to adjust the rotational resistance of the internal combustion engine corresponding to the selected gearshift position.

6. A hybrid vehicle in accordance with claim 5, wherein said accelerator-brake-released state control module controls the rotational resistance adjustment structure to increase the rotational resistance of the internal combustion engine in response to selection and setting of a gearshift position requiring a higher level of braking force among the multiple available gearshift positions.

7. A hybrid vehicle in accordance with claim 1, said hybrid vehicle further comprising:

a gearshift position setting module that, in response to a driver'"'"'s operation, selects and sets one gearshift position among multiple available gearshift positions, where the multiple available gearshift positions include a drive position requiring a first braking force as the braking force demand in the release of both the accelerator and the brake and a brake position requiring a second braking force, which is greater than the first braking force, as the braking force demand in the release of both the accelerator and the brake,

wherein when the accumulator unit is in the unchargeable state at the timing of the braking force demand, said accelerator-brake-released state control module controls the rotational resistance adjustment structure to adjust the rotational resistance of the internal combustion engine to a first rotational resistance in response to selection and setting of the drive position as the selected gearshift position, while controlling the rotational resistance adjustment structure to adjust the rotational resistance of the internal combustion engine to a second rotational resistance, which is higher than the first rotational resistance, in response to selection and setting of the brake position as the selected gearshift position.

8. A hybrid vehicle in accordance with claim 1, said hybrid vehicle being driven by directly utilizing part of output power of the internal combustion engine.

9. A hybrid vehicle in accordance with claim 8, said hybrid vehicle further comprising:

a three shaft-type power input output assembly that is linked to three shafts, an output shaft of the internal combustion engine, a rotating shaft of the engine-starting motor, and a driveshaft linked with an axle of said hybrid vehicle, and automatically 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.

10. A hybrid vehicle in accordance with claim 8, wherein the engine-starting motor is a pair-rotor motor having a first rotor that is connected to an output shaft of the internal combustion engine and a second rotor that is connected to a driveshaft linked with an axle of said hybrid vehicle and rotates relative to the first rotor through an electromagnetic function.

11. A control method of a hybrid vehicle including:

an internal combustion engine that is rotatable independently of a driving state of said hybrid vehicle;

a rotational resistance adjustment structure that adjusts a rotational resistance of the internal combustion engine;

an engine-starting motor that is driven for motoring of the internal combustion engine;

an accumulator unit that is chargeable and dischargeable; and

a driving motor that has power generation capability and inputs and outputs driving power through transmission of electric power to and from at least one of the engine-starting motor and the accumulator unit,

when the accumulator unit is in an unchargeable state at a timing of a braking force demand by release of both an accelerator and a brake, said control method controls the rotational resistance adjustment structure to adjust the rotational resistance of the internal combustion engine according to the braking force demand, controls the driving motor to drive said hybrid vehicle with a braking force equivalent to the braking force demand and to generate regenerative electric power, and controls the engine-starting motor to consume the regenerative electric power generated by the driving motor by having the engine-starting motor operate to motor the internal combustion engine.