CONTROL APPARATUS FOR POWER TRANSMISSION SYSTEM OF HYBRID VEHICLE

• US 20100138086A1
• Filed: 08/21/2008
• Published: 06/03/2010
• Est. Priority Date: 08/22/2007
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Iwase, Yuji, Tabata, Atsushi, Imamura, Tatsuya
• Granted Patent: US 8,370,010 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• 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 10/105 of electric type
• CPC Class Codes: B60W 2530/213 Fuel type
• CPC Class Codes: B60W 30/18 Propelling the vehicle
• CPC Class Codes: F02D 19/084 Blends of gasoline and alcohols, e.g. E85
• CPC Class Codes: F02D 19/088 by estimation, i.e. without using direct measurements of a corresponding sensor
• CPC Class Codes: F02D 2200/0612 determined by estimation
• CPC Class Codes: F02D 41/0025 Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
• CPC Class Codes: F02N 11/0818 Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A stop range changing unit changes an engine stop range, which is a cruise range in which an operation of an engine is stopped, based on a type of fuel that is burned in the engine and that is determined by a fuel type determination unit. Therefore, the engine is stopped or started up under a cruise condition that suits the fuel type. Accordingly, even if start-up performance of the engine varies due to variation of the fuel type, unfavorable effects of the variation in the start-up performance of the engine on a smooth motion of a hybrid vehicle is alleviated.

Claims

1. (canceled)

17. A control apparatus for a power transmission system of a hybrid vehicle including an internal combustion engine and an electric motor for driving the hybrid vehicle, comprising:

an operation stop range changing unit that changes an operation stop range for the internal combustion engine, which is a cruise range in which an operation of the internal combustion engine is stopped, based on a characteristic of fuel that is burned in the internal combustion engine.

2. The control apparatus according to claim 17, wherein changing the operation stop range for the internal combustion engine based on the characteristic of fuel is narrowing the operation stop range for the internal combustion engine when start-up performance of the internal combustion engine deteriorates.

3. The control apparatus according to claim 17, wherein when the operation stop range for the internal combustion engine is changed, an operation range for the electric motor, which is a cruise range in which the electric motor is operated, is kept unchanged.

4. The control apparatus according to claim 17, wherein when the operation stop range for the internal combustion engine is changed, an operation range for the electric motor, which is a cruise range in which the electric motor is operated, is changed in accordance with the change in the operation stop range for the internal combustion engine.

5. The control apparatus according to claim 4, wherein when the operation stop range for the internal combustion engine is narrowed, the operation range for the electric motor is narrowed.

6. The control apparatus according to claim 17, wherein the operation stop range for the internal combustion engine is a cruise range in which the operation of the internal combustion engine is determined to be stopped based on a vehicle speed.

7. The control apparatus according to claim 6, wherein the vehicle speed, at which the operation of the internal combustion engine is determined to be stopped, is lowered when start-up performance of the internal combustion engine deteriorates.

8. The control apparatus according to claim 17, wherein the operation stop range for the internal combustion engine is a cruise range in which the operation of the internal combustion engine is determined to be stopped based on an accelerator pedal operation amount.

9. The control apparatus according to claim 8, wherein the accelerator pedal operation amount, at which the operation of the internal combustion engine 8 is determined to be stopped, is decreased when start-up performance of the internal combustion engine deteriorates.

10. The control apparatus according to claim 17, wherein the operation stop range for the internal combustion engine is a cruise range in which the operation of the internal combustion engine is determined to be stopped based on a temperature of the internal combustion engine.

11. The control apparatus according to claim 10, wherein the temperature, at which the operation of the internal combustion engine is determined to be stopped, is raised when start-up performance of the internal combustion engine deteriorates.

12. The control apparatus according to claim 17, wherein the characteristic of the fuel is determined when an amount of fuel in a fuel tank provided in the hybrid vehicle increases.

13. The control apparatus according to claim 17, wherein the characteristic of the fuel is determined when opening of a lid for a fuel inlet of a fuel tank provided in the hybrid vehicle is detected.

14. The control apparatus according to claim 17, wherein:

the fuel is gasoline; and

the characteristic of the fuel is determined by detecting a ratio of ethanol to ethanol-blended-gasoline.

15. The control apparatus according to claim 17, wherein the power transmission system includes an electric differential unit which has a differential mechanism that is arranged between the internal combustion engine and a drive wheel, and a differential electric motor that is connected to the differential mechanism in such a manner that drive power is transmittable between the differential mechanism and the differential electric motor, and in which a differential state of the differential mechanism is controlled by controlling an operation state of the differential electric motor.

16. The control apparatus according to claim 17, wherein the operation stop range for the internal combustion engine includes an operation range for the electric motor, which is a cruise range in which the electric motor is operated, and a cruise range in which both the internal combustion engine and the electric motor are stopped.

18. A control method for a power transmission system of a hybrid vehicle including an internal combustion engine and an electric motor for driving the hybrid vehicle, comprising:

changing an operation stop range for the internal combustion engine, which is a cruise range in which an operation of the internal combustion engine is stopped, based on a characteristic of fuel that is burned in the internal combustion engine.