Control Device of Hybrid Vehicle and Hybrid Vehicle

• US 20090240387A1
• Filed: 04/27/2007
• Published: 09/24/2009
• Est. Priority Date: 06/07/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Asai, Naoki, Kawai, Takashi
• Granted Patent: US 8,660,725 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 10/26 for electrical energy, e.g. batteries or capacitors
• 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 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/103 Accelerator thresholds, e.g. kickdown
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/08 Circuits or control means specially adapted for starting of engines
• CPC Class Codes: F02N 11/0818 Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode
• CPC Class Codes: F02N 11/14 Starting of engines by means of electric starters with external current supply F02N11/12 takes precedence
• CPC Class Codes: F02N 2200/046 Energy or power necessary for starting
• CPC Class Codes: F02N 2300/104 Control of the starter motor torque
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A hybrid vehicle includes a motor generator used for driving the vehicle, an engine used in combination with the motor generator, an accelerator sensor arranged in an instructing unit instructing increase and decrease in required drive torque, and a control device starting the engine when a required engine output value exceeds a start threshold. The controller decreases the start threshold according to at least increase in required drive torque, and preferably decreases the start threshold further according to decrease in vehicle speed sensed by a vehicle speed sensor.

Claims

1. A control device of a hybrid vehicle using an engine and an electric motor in combination, comprising:

an instructing unit instructing increase and decrease in required drive torque; and

a control unit starting said engine when a required engine output value exceeds a start threshold, wherein

said control unit decreases said start threshold at least according to increase in said required drive torque.

2. The control device of the hybrid vehicle according to claim 1, further comprising:

a vehicle speed detecting unit detecting a vehicle speed, wherein

said control unit decreases said start threshold further according to decrease in vehicle speed detected by said vehicle speed detecting unit.

3. The control device of the hybrid vehicle according to claim 1, wherein

said control unit changes said start threshold further according to a quantity of residual electricity in an electric power storage device mounted on said hybrid vehicle.

4. The control device of the hybrid vehicle according to claim 1, wherein

said control unit calculates a required drive output based on a vehicle speed and said required drive torque, and calculates said required engine output value based on said required drive output and a quantity of residual electricity in an electric power storage device mounted on said hybrid vehicle.

5. The control device of the hybrid vehicle according to claim 1, wherein

said control unit determines a reference value of said start threshold based on a vehicle speed, and calculates said start threshold by adding, to said reference value, a value obtained by multiplying an increment depending on a quantity of residual electricity in an electric power storage device mounted on said hybrid vehicle by a reduction rate determined based on a vehicle speed and said required drive torque.

6. The control device of the hybrid vehicle according to claim 1, wherein

said hybrid vehicle has, as operation modes, an HV mode for controlling charge and discharge with respect to an electric power storage device such that a quantity of residual electricity in said electric power storage device may not deviate from a target value to a large extent, and an EV mode for causing said electric power storage device to perform primarily the discharge without setting a target value of a quantity of stored electricity,

said control unit determines said operation mode based on the quantity of the residual electricity in said electric power storage device, and

said control unit uses a reference value as said start threshold in said HV mode and uses in said EV mode a value obtained by adding a value decreasing with increase in said required drive torque to said reference value as said start threshold.

7. The control device of the hybrid vehicle according to claim 6, wherein

said control unit controls, in said HV mode, charge and discharge with respect to said electric power storage device to keep said quantity of the residual electricity within a range between predetermined maximum and minimum values, and

said control unit changes said operation mode from said EV mode to said HV mode when the quantity of the residual electricity becomes smaller than a predetermined value.

8. A hybrid vehicle comprising:

a motor used for driving the vehicle;

an engine used in combination with said motor;

an instructing unit instructing increase and decrease in required drive torque; and

a control unit starting said engine when a required engine output value exceeds a start threshold, wherein

said control unit decreases said start threshold at least according to increase in said required drive torque.

9. The hybrid vehicle according to claim 8, further comprising

an electric power storage device supplying an electric power to said motor;

and

a charging port for charging said electric power storage device from an outside of the vehicle.

10. The hybrid vehicle according to claim 8, further comprising

a vehicle speed detecting unit detecting a vehicle speed, wherein

said control unit decreases said start threshold further according to decrease in vehicle speed detected by said vehicle speed detecting unit.

11. The hybrid vehicle according to claim 8, wherein

said control unit changes said start threshold further according to a quantity of residual electricity in an electric power storage device mounted on said hybrid vehicle.

12. The hybrid vehicle according to claim 8, wherein

said control unit calculates a required drive output based on a vehicle speed and said required drive torque, and calculates said required engine output value based on said required drive output and a quantity of residual electricity in an electric power storage device mounted on said hybrid vehicle.

13. The hybrid vehicle according to claim 8, wherein

said control unit determines a reference value of said start threshold based on a vehicle speed, and calculates said start threshold by adding, to said reference value, a value obtained by multiplying an increment depending on a quantity of residual electricity in an electric power storage device mounted on said hybrid vehicle by a reduction rate determined based on a vehicle speed and said required drive torque.

14. The control device of the hybrid vehicle according to claim 8, wherein

said hybrid vehicle has, as operation modes, an HV mode for controlling charge and discharge with respect to an electric power storage device such that a quantity of residual electricity in said electric power storage device may not deviate from a target value to a large extent, and an EV mode for causing said electric power storage device to perform primarily the discharge without setting a target value of a quantity of stored electricity,

said control unit determines said operation mode based on the quantity of the residual electricity in said electric power storage device, and

said control unit uses a reference value as said start threshold in said HV mode and uses in said EV mode a value obtained by adding a value decreasing with increase in said required drive torque to said reference value as said start threshold.

15. The hybrid vehicle according to claim 14, wherein

said control unit controls, in said HV mode, charge and discharge with respect to said electric power storage device to keep said quantity of the residual electricity within a range between predetermined maximum and minimum values, and

said control unit changes said operation mode from said EV mode to said HV mode when the quantity of the residual electricity becomes smaller than a predetermined value.