Vehicle travel control system

• US 9,067,583 B2
• Filed: 04/14/2009
• Issued: 06/30/2015
• Est. Priority Date: 04/14/2008
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Taguchi, Koji
• Primary Examiner(s): Nguyen, Cuong H
• Application Number:
  US12/937,929
• Publication Number:
  US 20110046835A1
• Time in Patent Office: 2,268 Days
• Field of Search: 701/22, 701/70, 701/20, 701/117, 701/119, 701/26, 701532-533, 701/79, 701/514, 701/300, 701/435, 701/519, 180/65.21, 180/65.1, 180/65.2, 180/168, 709223-224, 340/464, 340/467, 903/902, 474/4
• US Class Current: 1/1
• 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 20/12 using control strategies taking into account route information estimation or calculation of non-directly measurable driving parameters B60W40/00
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: G08G 1/096827 where the route is computed onboard
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

An ECU that integrally controls a vehicle travel control system includes an initial travel plan producing section which produces an initial travel plan including a decelerating interval in which an engine of a vehicle is stopped to decelerate the vehicle, a travel plan reconfiguring section which reconfigures the initial travel plan produced by the initial travel plan reconfiguring section, and a travel control section which controls travel of the vehicle based on a travel plan. When a non-stop state of the engine occurs while the vehicle is traveling, the travel plan reconfiguring section reconfigures the initial travel plan so that target deceleration in the decelerating interval in the initial travel plan is reset to new target deceleration that is larger deceleration.

Claims

1. A vehicle travel control system for controlling travel of a vehicle based on a travel plan, comprising:

a controller including circuitry,

wherein the circuitry includes;

initial travel plan producing circuitry configured to produce an initial travel plan including a decelerating interval in which an internal combustion engine is stopped to decelerate the vehicle; and

first replanning circuitry configured to replan the initial travel plan so that target deceleration in the decelerating interval is set larger than that in the initial travel plan when a non-stop state of the internal combustion engine occurs while the vehicle is traveling.

2. The vehicle travel control system according to claim 1, wherein the first replanning circuitry is configured to replan the initial travel plan so that target acceleration in an accelerating interval that follows the decelerating interval is set larger than that in the initial travel plan when the non-stop state of the internal combustion engine occurs while the vehicle is traveling.

3. The vehicle travel control system according to claim 1, wherein

a driving system of the vehicle is a hybrid system in which the vehicle is driven by the internal combustion engine and a motor having a battery as a power source, and

the first replanning circuitry is configured to replan the initial travel plan with new target deceleration in the decelerating interval which is a value that is a product of maximum regenerative braking deceleration at which deceleration produces maximum regeneration and ideal heat efficiency of the internal combustion engine divided by a product of heat efficiency of the internal combustion engine and charge-discharge efficiency of the battery at the present time.

4. The vehicle travel control system according to claim 3, wherein the first replanning circuitry is configured to replan the initial travel plan with new target acceleration which is a value that is acceleration corresponding to an output limit of the battery added to target acceleration in an accelerating interval.

5. The vehicle travel control system according to claim 1, wherein the initial travel plan producing circuitry is configured to estimate an estimated non-stop interval in which the internal combustion engine is brought into the non-stop state and produces the initial travel plan with use of a heat efficiency preferential evaluation equation for a case that the internal combustion engine is in the non-stop state.

6. The vehicle travel control system according to claim 1, wherein the circuitry further includes:

provisional traveling time computing circuitry configured to compute a provisional traveling time that is a specified time added to a traveling time for each interval in the initial travel plan;

provisional travel plan producing circuitry configured to produce a provisional travel plan by an optimization process with a constraint condition being the provisional traveling time;

provisional fuel consumption computing circuitry configured to compute fuel consumption for each interval in the provisional travel plan;

expected fuel efficiency improvement computing circuitry configured to compute an expected fuel efficiency improvement of the provisional travel plan with respect to the initial travel plan based on the fuel consumption for each of the intervals in the provisional travel plan and fuel consumption for each of the intervals in the initial travel plan;

surplus traveling time computing circuitry configured to subtract a traveling time for each interval in a travel plan replanned by the first replanning circuitry from the traveling time for each of the intervals in the initial travel plan to calculate a surplus traveling time for each of the intervals; and

second replanning circuitry configured to replan the travel plan with a constraint condition being a traveling time that the surplus traveling time is added to the traveling time for the interval that the expected fuel efficiency improvement is the largest.

7. The vehicle travel control system according to claim 6, wherein the second replanning circuitry is configured to replan the initial travel plan in response to a cause of the non-stop state of the internal combustion engine.

12. The vehicle travel control system according to claim 1, wherein the non-stop state of the internal combustion engine is a state where the internal combustion engine cannot be stopped.

13. The vehicle travel control system according to claim 1, wherein the non-stop state of the internal combustion engine is a state where the internal combustion engine cannot be stopped while the vehicle is traveling.

14. The vehicle travel control system according to claim 1, wherein the non-stop state of the internal combustion engine occurs when at least one of:

the internal combustion engine requires warm-up,

a heater requires warm-up, and

a battery requires warm-up.

15. The vehicle travel control system according to claim 1, wherein the first replanning circuitry is configured to replan the initial travel plan based upon a cause of the non-stop state of the internal combustion engine.

16. The vehicle travel control system according to claim 15, wherein when the cause of the non-stop state of the internal combustion engine is that a heater requires warm-up, the first replanning circuitry is configured to reset deceleration in the deceleration interval to deceleration resulting from a fuel cut-off state of the internal combustion engine.

17. The vehicle travel control system according to claim 15, wherein when the cause of the non-stop state of the internal combustion engine is that a battery requires warm up, the first replanning circuitry is configured to determine whether or not a current travel interval that the vehicle is travelling is the decelerating interval.

18. The vehicle travel control system according to claim 17, wherein when the current travel interval that the vehicle is travelling is the deceleration interval, the first replanning circuitry is configured to reset the target deceleration in the deceleration interval to a maximum regenerating braking deceleration at which maximum regenerative braking is made.

19. The vehicle travel control system according to claim 17, wherein when the current travel interval that the vehicle is travelling is not the deceleration interval, the first replanning circuitry is configured to determine whether or not the current travel interval that the vehicle is travelling is an accelerating interval.

20. The vehicle travel control system according to claim 19, wherein when the current travel interval that the vehicle is travelling is the acceleration interval, the first replanning circuitry is configured to reset a target acceleration in the acceleration interval to an acceleration at which the vehicle is accelerated with a maximum electric power.

8. A vehicle travel control system for controlling travel of a vehicle based on a travel plan, comprising:

a controller including circuitry,

wherein the circuitry includes;

initial travel plan producing circuitry configured to estimate fuel consumption of the vehicle and produce an initial travel plan in consideration of a fuel consumption characteristic;

actual fuel consumption computing circuitry configured to compute an actual fuel consumption of the vehicle which travels based on the initial travel plan; and

travel plan reconfiguring circuitry configured to reconfigure the initial travel plan so that an expected fuel consumption becomes less than the initial travel plan if the actual fuel consumption exceeds the expected fuel consumption of the initial travel plan.

9. An ECU-implemented vehicle travel control method for controlling travel of a vehicle based on a travel plan, comprising:

producing, via the ECU, an initial travel plan including a decelerating interval in which an internal combustion engine is stopped to decelerate the vehicle; and

replanning, via the ECU, the initial travel plan so that target deceleration in the decelerating interval is set larger than that in the initial travel plan when a non-stop state of the internal combustion engine occurs while the vehicle is traveling.

10. The vehicle travel control method according to claim 9, further comprising

replanning, via the ECU, the initial travel plan so that target acceleration in an accelerating interval that follows the decelerating interval is set larger than the initial travel plan when the non-stop state of the internal combustion engine occurs while the vehicle is traveling.

11. The vehicle travel control method according to claim 9, further comprising:

calculating, via the ECU, a provisional traveling time that is a predetermined time added to a traveling time for each interval of the initial travel plan;

producing, via the ECU, a provisional travel plan by optimization process with a constraint condition being the provisional traveling time;

computing, via the ECU, fuel consumption for each interval in the provisional travel plan;

computing, via the ECU, an expected fuel efficiency improvement of the provisional travel plan with respect to the initial travel plan based on the fuel consumption for each of the intervals in the provisional travel plan and fuel consumption for each of the intervals in the initial travel plan;

subtracting, via the ECU, a traveling time for each interval in a replanned travel plan from the traveling time for each of the intervals in the initial travel plan to compute a surplus traveling time for each of the intervals; and

further replanning, via the ECU, the travel plan with a constraint condition being a traveling time that the surplus traveling time is added to the traveling time for the interval that the expected fuel efficiency improvement is the largest.