Vehicle control apparatus

• US 6,930,405 B2
• Filed: 09/30/2003
• Issued: 08/16/2005
• Est. Priority Date: 10/15/2002
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Gunji, Kenichiro
• Primary Examiner(s): Schuberg, Darren
• Assistant Examiner(s): Gonzalez, Julio C.
• Application Number:
  US10/673,199
• Publication Number:
  US 20040070270A1
• Time in Patent Office: 686 Days
• Field of Search: 290/40.C, 701/69, 701/22, 701/41, 701/70, 303/152, 475/204, 477/3, 477/4, 180/65.1, 180/65, 180/65.3, 180/65.8
• US Class Current: 290/40.00C
• CPC Class Codes: B60K 17/356 having fluid or electric motor, for driving one or more wheels disposition of motor in, or adjacent to, traction wheel B60K7/00
• CPC Class Codes: B60K 23/08 for changing number of driven wheels , for switching from driving one axle to driving two or more axles B60K17/3515 takes precedence
• CPC Class Codes: B60K 23/0808 for varying torque distribution between driven axles, e.g. by transfer clutch
• CPC Class Codes: B60K 6/44 Series-parallel type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/485 Temperature
• CPC Class Codes: B60L 7/10 Dynamic electric regenerative braking B60L7/22 takes precedence
• CPC Class Codes: B60L 7/20 Braking by supplying regenerated power to the prime mover of vehicles comprising engine-driven generators
• CPC Class Codes: B60T 1/10 by utilising wheel movement for accumulating energy, e.g. driving air compressors
• CPC Class Codes: B60T 13/586 the retarders being of the electric type
• CPC Class Codes: B60T 2270/608 Electronic brake distribution (EBV/EBD) features related thereto
• CPC Class Codes: B60T 7/00 Brake-action initiating means
• CPC Class Codes: B60T 8/1766 Proportioning of brake forces according to vehicle axle loads, e.g. front to rear of vehicle
• CPC Class Codes: B60T 8/1769 specially adapted for vehicles having more than one driven axle, e.g. four-wheel drive vehicles
• CPC Class Codes: B60T 8/267 for hybrid systems with different kind of brakes on different axles
• 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 2510/107 : Temperature
• CPC Class Codes: B60W 2520/10 : Longitudinal speed
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 30/18127 : Regenerative braking
• 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 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 10/84 : Data processing systems or methods, management, administration

Abstract

A vehicle control apparatus performs regenerative braking by regeneratively operating first and second motor-generators to apply first and second braking torques in response to a deceleration request. The vehicle control apparatus is improves the efficiency in regeneratively generating electric power without greatly disturbing the balance between the. The control apparatus calculates an ideal front-rear wheel distribution ratio for front wheel braking torque and the rear wheel braking torque, and also calculates a distribution allowance for the ideal front-rear wheel distribution ratio. The control apparatus then corrects the ideal front-rear wheel distribution ratio within the distribution allowance such that the electric power generation efficiencies of the first motor-generator connected to the rear wheels and the second motor-generator connected to the front wheels are increased. Based on the corrected front-rear wheel distribution ratio, the control apparatus calculates the torque command values to be sent to the motor-generators.

Claims

1. A vehicle control apparatus comprising:

a first motor-generator operatively coupled to at least one first wheel;

a second motor-generator operatively coupled to at least one second wheel that is not connected to the first motor-generator; and

a regenerative braking component configured and arranged to perform regenerative braking in which a first braking torque is applied to the first wheel by regeneratively operating the first motor-generator while a second braking torque is applied to the second wheel by regeneratively operating the second motor-generator,

the regenerative braking component configured and arranged to include

an ideal front-rear wheel distribution ratio calculating section configured and arranged to calculate an ideal front-rear wheel distribution ratio between the first braking torque applied to the first wheel and the second braking torque applied to the second wheel;

a distribution allowance calculating section configured and arranged to calculate a distribution allowance of the ideal front-rear wheel distribution ratio; and

a distribution ratio correcting section configured and arranged to correct the ideal front-rear wheel distribution ratio within a range of the distribution allowance to increase electric power generation efficiency of at least one of the first and second motor-generators.

2. The vehicle control apparatus as recited in claim 1, further comprising:

a vehicle speed detecting section configured and arranged to a vehicle speed, and

a braking torque calculating section configured and arranged to calculate a required braking torque based on a deceleration request, and

the distribution ratio correcting section being further configured to correct the ideal front-rear wheel distribution ratio based on the vehicle speed detected and the required braking torque calculated.

3. The vehicle control apparatus as recited in claim 2, wherein

the regenerative braking component is further configured to include a drive mode detecting section to determine if selection of one of a two-wheel drive mode and a four-wheel drive mode;

and

the distribution allowance calculating section is further configured to calculate the distribution allowance differently depending on which of the two-wheel drive mode and the four-wheel drive mode has been determined to be selected.

4. The vehicle control apparatus as recited in claim 3, further comprising

an engine configured and arranged to drives one of the first and second wheels.

5. The vehicle control apparatus as recited in claim 4, wherein

the regenerative braking component includes a braking device configured to apply a brake torque to at least the first and second wheels such that the electric power generation efficiency of at least one of the first and second motor-generators is increased.

6. The vehicle control apparatus as recited in claim 1, wherein

the regenerative braking component is further configured to include a drive mode detecting section to determine if selection of one of a two-wheel drive mode and a four-wheel drive mode;

and

the distribution allowance calculating section is further configured to calculate the distribution allowance differently depending on which of the two-wheel drive mode and the four-wheel drive mode has been determined to be selected.

7. The vehicle control apparatus as recited in claim 1, further comprising

an engine configured and arranged to drives one of the first and second wheels.

8. The vehicle control apparatus as recited in claim 1, wherein

the regenerative braking component includes a braking device configured to apply a brake torque to at least the first and second wheels such that the electric power generation efficiency of at least one of the first and second motor-generators is increased.

9. A vehicle control apparatus comprising:

first motor-generator means for driving at least one first wheel and for generating electricity from the first wheel;

second motor-generator means for driving at least one second wheel that is not connected to the first motor-generator means and for generating electricity from the second wheel; and

regenerative braking means for performing regenerative braking in which a first braking torque is applied to the first wheel by regeneratively operating the first motor-generator means while a second braking torque is applied to the second wheel by regeneratively operating the second motor-generator means,

the regenerative braking means being configured and arranged for

calculating an ideal front-rear wheel distribution ratio between the first braking torque applied to the first wheel and the second braking torque applied to the second wheel;

calculating an allowance of the ideal front-rear wheel distribution ratio; and

correcting the ideal front-rear wheel distribution ratio within a range of the distribution allowance to increase electric power generation efficiency of at least one of the first and second motor-generators.

10. A method of vehicle control apparatus comprising:

first motor-generator means for driving at least one first wheel and for generating electricity from the first wheel;

second motor-generator means for driving at least one second wheel that is not connected to the first motor-generator and for generating electricity from the second wheel; and

performing regenerative braking in which a first braking torque is applied to at least one first wheel by regeneratively operating a first motor-generator while a second braking torque is applied to at least one second wheel that is not connected to the first motor-generator by regeneratively operating a second motor-generator,

calculating an ideal front-rear wheel distribution ratio between the first braking torque applied to the first wheel and the second braking torque applied to the second wheel;

calculating an allowance of the ideal front-rear wheel distribution ratio; and

correcting the ideal front-rear wheel distribution ratio within a range of the distribution allowance to increase electric power generation efficiency of at least one of the first and second motor-generators.