Hybrid vehicle control system

• US 20060009884A1
• Filed: 07/01/2005
• Published: 01/12/2006
• Est. Priority Date: 07/06/2004
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Mensler, Michel, Joe, Shinichiro
• Granted Patent: US 7,693,637 B2
• Time in Patent Office: Days
• US Class Current: 701/1
• CPC Class Codes: B60K 2006/264 with outer rotor and inner stator
• CPC Class Codes: B60K 2006/266 with two coaxial motors or generators
• CPC Class Codes: B60K 6/387 Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2260/26 Transition between different drive modes
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/105 of electric type
• 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 2510/244 Charge state
• CPC Class Codes: B60W 30/188 Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: F16H 2037/103 Power split variators with each end of the CVT connected or connectable to a Ravigneaux set
• CPC Class Codes: Y02T 10/40 Engine management systems
• 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
• CPC Class Codes: Y10S 903/903 : having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/912 : Drive line clutch
• CPC Class Codes: Y10S 903/917 : with transmission for changing gear ratio
• CPC Class Codes: Y10S 903/918 : Continuously variable
• CPC Class Codes: Y10S 903/919 : Stepped shift
• CPC Class Codes: Y10S 903/945 : Characterized by control of gearing, e.g. control of transmission ratio
• CPC Class Codes: Y10S 903/946 : Characterized by control of driveline clutch

Abstract

A vehicle control system is comprised of a controller which is arranged to select an optimal mode adapted to a driving point of a vehicle from an optimal mode map of defining a plurality of running modes of the vehicle, to detect a generation of a mode transition in the optimal mode map, and to hold a current running mode selected before the transition for a holding time period when the generation of the mode transition is detected.

Claims

1. A vehicle control system comprising:

a controller arranged

to select an optimal mode adapted to a driving point of a vehicle from an optimal mode map of defining a plurality of running modes of the vehicle,

to detect a generation of a mode transition in the optimal mode map, and

to hold a current running mode selected before the transition for a holding time period when the generation of the mode transition is detected.

2. The vehicle control system as claimed in claim 1, wherein the controller is further arranged to calculate a time period necessary for the mode transition at the driving point at which the generation of the mode transition is detected, the holding time period being determined based on the mode transition time period.

3. The vehicle control system as claimed in claim 1, wherein the controller is further arranged to calculate energy necessary for the mode transition at the driving point at which the generation of the mode transition is detected, and to calculate energy coincident time by which the energy of the maintained mode is coincident with energy of the transition mode, the holding time period being determined based on the energy coincidence time.

4. The vehicle control system as claimed in claim 1, wherein the controller is further arranged to limit a transition speed of the mode transition, the holding time period being set such that the transition speed becomes smaller than or equal to the limited transition speed.

5. The vehicle control system as claimed in claim 1, wherein the controller is further arranged to estimate a running load of the vehicle, the holding time period being determined based on the estimated running load.

6. The vehicle control system as claimed in claim 1, further comprising:

a differential gear transmission comprising a planetary gearset whose rotating elements are connected to a plurality of driving source including an internal combustion engine and at least one motor, an engagement element which is attached to one of the rotating elements and which produces a fixed transmission ratio by putting the engagement element in an engaged state and produces a continuously variable transmission ratio by putting the engagement element in a disengaged state, and an engine clutch for engaging and disengaging a connection between the engine and the planetary gearset; and

a battery connected to the motor to charge and discharge electric power from and to the motor,

wherein the controller is further arranged to control the engagement and the disengagement of each of the engagement element and the engine clutch to produce a desired running mode.

7. The vehicle control system as claimed in claim 6, wherein the controller is further arranged to limit the mode transition speed according to at least one of a maximum discharging electric power and a maximum charging electric power of the battery.

8. The vehicle control system as claimed in claim 6, wherein the controller is further arranged to limit the mode transition speed by limiting a revolution speed of one of the rotating elements of the differential gear transmission.

9. The vehicle control system as claimed in claim 6, wherein the controller is further arranged to execute the holding of the current running mode when the running mode is transited from a first running mode produced by disengaging both of the engine clutch and the engagement element to a second running mode produced by disengaging the engine clutch and by engaging the engagement element, estimate a running load of the vehicle.

10. A vehicle control system comprising:

a transmission comprising a planetary gearset whose rotating elements are connected to an internal combustion engine, at least one motor and an output, an engine clutch through which a rotating element of the planetary gearset is connected to the engine, and an engagement element which is capable of engaging one of the rotating elements except for the rotating elements connected to the engine and an output, the transmission being capable of producing a plurality of running modes by changing the engagement states of the engine clutch and the engagement element; and

a controller arranged

to select an optimal mode adapted to a driving point of a vehicle from an optimal mode map of defining the running modes,

to detect a generation of a mode transition in the optimal mode map, and

to hold a current running mode selected before the transition, for a holding time period from the generation of the mode transition, when the generation of the mode transition is detected.

11. A method of controlling a hybrid vehicle, comprising:

selecting an optimal mode adapted to a driving point of the hybrid vehicle from an optimal mode map of defining a plurality of running modes;

detecting a generation of a mode transition in the optimal mode map; and

holding a current running mode selected before the transition for a holding time period when the generation of the mode transition is detected.

12. A vehicle control system comprising:

optimal mode selecting means for select an optimal mode adapted to a driving point of a vehicle from an optimal mode map of defining a plurality of running modes of the vehicle;

mode transition detecting means for detecting a generation of a mode transition in the optimal mode map; and

mode transition holding means for hold a current running mode selected before the transition for a holding time period when the generation of the mode transition is detected.