Control system for hybrid vehicle

• US 6,140,780 A
• Filed: 09/16/1998
• Issued: 10/31/2000
• Est. Priority Date: 09/17/1997
• Status: Expired due to Term

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Yano, Toru, Sugiyama, Tetsu, Tamagawa, Yutaka, Tatara, Yusuke, Oshima, Yoshikazu, Ishikawa, Motoshi
• Primary Examiner(s): Martin, David
• Assistant Examiner(s): Leykin, Rita
• Application Number:
  US09/153,930
• Time in Patent Office: 776 Days
• Field of Search: 318/139, 318/375, 318/376, 318/377, 318/378, 318/379, 318/380, 318/381, 318/432, 318/434, 318/140-143, 318/146, 318/150-153, 180/65.4-65.8, 290/9, 290/14, 290/27
• US Class Current: 318/139
• CPC Class Codes: B60K 6/24 characterised by the combustion engines
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2260/42 by adaptive correction
• CPC Class Codes: B60L 50/30 using propulsion power stored mechanically, e.g. in fly-wheels
• 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 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/18 including control of braking systems
• 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 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 20/14 in conjunction with braking regeneration
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2530/16 Driving resistance
• CPC Class Codes: B60W 2540/10 : Accelerator pedal position
• CPC Class Codes: B60W 2710/0605 : Throttle position
• CPC Class Codes: B60W 2710/0616 : Position of fuel or air injector
• CPC Class Codes: B60W 2710/0666 : Engine torque
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 30/18127 : Regenerative braking
• CPC Class Codes: B60W 30/18136 : Engine braking
• CPC Class Codes: Y02T 10/40 : Engine management systems
• CPC Class Codes: Y02T 10/60 : Other road transportation technologies with climate change mitigation effect
• 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 10/84 : 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 903/905 : Combustion engine
• CPC Class Codes: Y10S 903/917 : with transmission for changing gear ratio
• 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 903/947 : Characterized by control of braking, e.g. blending of regeneration, friction braking

Abstract

A control system controls a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle and converting kinetic energy of the drive axle into electric energy in a regenerative mode, and an electric energy storage unit connected through a power drive unit to the electric motor, for storing electric energy. The control system has a regenerative quantity determining unit which includes first, second, and third first regenerative quantity establishing units. The first regenerative quantity establishing unit establishes a first regenerative quantity for the electric motor based on a vehicle speed of the hybrid vehicle when the supply of fuel to the engine is stopped upon deceleration of the hybrid vehicle. The second regenerative quantity establishing unit establishes a second regenerative quantity for the electric motor based on a remaining capacity of the electric energy storage unit. The third regenerative quantity establishing unit establishes a third regenerative quantity for the electric motor based on a temperature of the drive control circuit. A pumping loss controlling unit controls pumping losses of the engine based on the first, second, and third regenerative quantities.

Claims

1. A control system for controlling a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle and converting kinetic energy of the drive axle into electric energy in a regenerative mode, and electric energy storage means connected through a power drive unit to the electric motor, for storing electric energy, comprising:

regenerative quantity determining means including first regenerative quantity establishing means for establishing a first regenerative quantity for the electric motor based on a vehicle speed of the hybrid vehicle when the supply of fuel to the engine is stopped upon deceleration of the hybrid vehicle, second regenerative quantity establishing means for establishing a second regenerative quantity for the electric motor based on a remaining capacity of the electric energy storage means, and third regenerative quantity establishing means for establishing a third regenerative quantity for the electric motor based on a temperature of the power drive unit; and

pumping loss controlling means for controlling pumping losses of the engine based on said first, second, and third regenerative quantities established respectively by said first, second, and third regenerative quantity establishing means,

wherein said pumping loss controlling means comprises means for minimizing the pumping losses of the engine if any one of said second and third regenerative quantities established respectively by said second and third regenerative quantity establishing means is equal to or greater than said first regenerative quantity established by said first regenerative quantity establishing means.

6. A control system according to claim 1, wherein said pumping loss controlling means has an exhaust gas recirculation control valve for controlling an amount of exhaust gases recirculated from an exhaust pipe of the engine to an intake pipe thereof, and means for fully opening said exhaust gas recirculation control valve when the electric motor is controlled in the regenerative mode based on said first regenerative quantity, and operating said exhaust gas recirculation control valve in a closing direction depending on said second or third regenerative quantity when the electric motor is controlled in the regenerative mode based on said second or third regenerative quantity.

7. A control system according to claim 1, wherein said pumping loss controlling means has an intake valve or an exhaust valve of the engine and an actuator for fully opening said intake valve or said exhaust valve, and means for controlling said actuator to keep at least one of said intake valve and said exhaust valve fully open when the electric motor is controlled in the regenerative mode based on said first regenerative quantity, and controlling said actuator to vary a valve lift or a valve opening period of said intake valve or said exhaust valve depending on said second or third regenerative quantity when the electric motor is controlled in the regenerative mode based on said second or third regenerative quantity.

8. A control system according to claim 1, wherein said pumping loss controlling means has an intake valve and an exhaust valve of the engine and an actuator for fully opening said intake valve and said exhaust valve, and means for controlling said actuator to keep said intake valve and said exhaust valve fully closed when the electric motor is controlled in the regenerative mode based on said first regenerative quantity, and controlling said actuator to vary a valve lift or a valve opening period of at least one of said intake valve and said exhaust valve depending on said second or third regenerative quantity when the electric motor is controlled in the regenerative mode based on said second or third regenerative quantity.

2. A control system for controlling a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle and converting kinetic energy of the drive axle into electric energy in a regenerative mode, and electric energy storage means connected through a power drive unit to the electric motor, for storing electric energy, comprising:

regenerative quantity determining means including first regenerative quantity establishing means for establishing a first regenerative quantity for the electric motor based on a vehicle speed of the hybrid vehicle when the supply of fuel to the engine is stopped upon deceleration of the hybrid vehicle, second regenerative quantity establishing means for establishing a second regenerative quantity for the electric motor based on a remaining capacity of the electric energy storage means, and third regenerative quantity establishing means for establishing a third regenerative quantity for the electric motor based on a temperature of the power drive unit; and

pumping loss controlling means for controlling pumping losses of the engine based on said first, second, and third regenerative quantities established respectively by said first, second, and third regenerative quantity establishing means,

wherein said pumping loss controlling means comprises means controls the pumping losses of the engine based on a difference between said first regenerative quantity and said second or third regenerative quantity if any one of said second and third regenerative quantities established respectively by said second and third regenerative quantity establishing means is smaller than said first regenerative quantity established by said first regenerative quantity establishing means.

3. A control system for controlling a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle and converting kinetic energy of the drive axle into electric energy in a regenerative mode, and electric energy storage means connected through a power drive unit to the electric motor, for storing electric energy, comprising:

regenerative quantity determining means including first regenerative quantity establishing means for establishing a first regenerative quantity for the electric motor based on a vehicle speed of the hybrid vehicle when the supply of fuel to the engine is stopped upon deceleration of the hybrid vehicle, second regenerative quantity establishing means for establishing a second regenerative quantity for the electric motor based on a remaining capacity of the electric energy storage means, and third regenerative quantity establishing means for establishing a third regenerative quantity for the electric motor based on a temperature of the power drive unit; and

pumping loss controlling means for controlling pumping losses of the engine based on said first, second, and third regenerative quantities established respectively by said first, second, and third regenerative quantity establishing means,

wherein said regenerative quantity determining means comprises means for applying said first regenerative quantity as a determined regenerative quantity to said power drive unit if any one of said first and second regenerative quantities established respectively by said first and second regenerative quantity establishing means is equal to or greater than said first regenerative quantity established by said first regenerative quantity establishing means, and for applying a smaller one of said second and third regenerative quantities as a determined regenerative quantity to said powerdrive unit if any one of said second and third regenerative quantities established respectively by said second and third regenerative quantity establishing means is smaller than said first regenerative quantity established by said first regenerative quantity establishing means.

4. A control system for controlling a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle and converting kinetic energy of the drive axle into electric energy in a regenerative mode, and electric energy storage means connected through a power drive unit to the electric motor, for storing electric energy, comprising:

regenerative quantity determining means including first regenerative quantity establishing means for establishing a first regenerative quantity for the electric motor based on a vehicle speed of the hybrid vehicle when the supply of fuel to the engine is stopped upon deceleration of the hybrid vehicle, second regenerative quantity establishing means for establishing a second regenerative quantity for the electric motor based on a remaining capacity of the electric energy storage means, and third regenerative quantity establishing means for establishing a third regenerative quantity for the electric motor based on a temperature of the power drive unit; and

pumping loss controlling means for controlling pumping losses of the engine based on said first, second, and third regenerative quantities established respectively by said first, second, and third regenerative quantity establishing means,

wherein said first regenerative quantity establishing means comprises means for calculating the first regenerative quantity based on a decelerating resistance established depending on said vehicle speed and a running resistance to the hybrid vehicle at said vehicle speed.

5. A control system for controlling a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle and converting kinetic energy of the drive axle into electric energy in a regenerative mode, and electric energy storage means connected through a power drive unit to the electric motor, for storing electric energy, comprising:

regenerative quantity determining means including first regenerative quantity establishing means for establishing a first regenerative quantity for the electric motor based on a vehicle speed of the hybrid vehicle when the supply of fuel to the engine is stopped upon deceleration of the hybrid vehicle, second regenerative quantity establishing means for establishing a second regenerative quantity for the electric motor based on a remaining capacity of the electric energy storage means, and third regenerative quantity establishing means for establishing a third regenerative quantity for the electric motor based on a temperature of the power drive unit; and

pumping loss controlling means for controlling pumping losses of the engine based on said first, second, and third regenerative quantities established respectively by said first, second, and third regenerative quantity establishing means,

wherein said regenerative quantity determining means comprises means for determining a regenerative quantity of nil to disable said pumping loss control means if any one of said remaining capacity of the electric energy storage means and said temperature of the power drive unit exceeds a predetermined threshold.