Hybrid vehicle

• US 6,048,289 A
• Filed: 03/08/1999
• Issued: 04/11/2000
• Est. Priority Date: 03/30/1998
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Aoyama, Shunichi, Hattori, Noboru, Kitada, Shinichiro, Matsuo, Isaya
• Primary Examiner(s): ESTREMSKY, SHERRY LYNN
• Application Number:
  US09/263,837
• Time in Patent Office: 400 Days
• Field of Search: 477/2, 477/3, 477/5, 477/8, 477/15, 180/65.2, 180/65.4, 180/65.7
• US Class Current: 477/15
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• 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 10/26 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 2510/244 Charge state
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/06 Ignition switch
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2540/16 Ratio selector position
• CPC Class Codes: F16H 61/66 specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38
• 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: Y10S 903/918 : Continuously variable
• 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

In a hybrid vehicle, an internal combustion engine and a first electric propulsion motor are linked to an input axle of a clutch and an input axle of a continuously variable transmission and a second electric propulsion motor are linked to an output axle of the clutch. A propulsion mechanism for transmitting a power from an output axle of the continuously variable transmission to drive axles, a third electric propulsion motor used to drive a hydraulic system of the continuously variable transmission, a battery supply, a power inverter for charging and discharging between the battery supply and the first, second, and third electric propulsion motors, and a controller for controlling operations of the power inverter, the battery supply, the first, second, and third motors, and the continuously variable transmission are provided in the hybrid vehicle.

Claims

1. A vehicle comprising:

a clutch having an input axle thereof and an output axle thereof;

an internal combustion engine for driving the input axle of the clutch;

a first electric propulsion motor for driving the input axle of the clutch;

a second electric propulsion motor for driving the output axle of the clutch;

a continuously variable transmission having an input axle connected to the output axle of the clutch via the second electric propulsion motor and an output axle connected to the drive wheels of the vehicle;

a third electric propulsion motor for driving a hydraulic system of the continuously variable transmission;

a battery supply;

a power inverter for charging and discharging between the battery supply and the first, second, and third electric propulsion motors; and

a controller for controlling operations of the engine, the power inverter, the first, second, and third electric propulsion motors, and the continuously variable transmission.

2. A vehicle as claimed in claim 1, which further comprises:

an operational member through which the vehicle is selected to start forward or backward;

an accelerator detector for detecting a manipulated variable of an accelerator;

a brake operation detector for detecting a manipulated variable of a brake unit;

a vehicular velocity detector for detecting a vehicular velocity;

a charge-discharge capacity detector for detecting either or both of charge and discharge capacities that the battery supply has; and

wherein the controller includes a first determinator for determining an engagement or release of the clutch and either a supply of fuel to the engine or a stop of the supply of fuel to the engine on the basis of the manipulated variables of the accelerator and the brake unit, the vehicular velocity, and either or both of the charge and discharge capacities that the battery supply has when the vehicle is selected through the operational member to start forward.

3. A vehicle as claimed in claim 2, wherein the controller includes:

a second determinator for determining whether the vehicular velocity is below a predetermined value of the vehicular velocity;

a third determinator for determining whether the manipulated variable of the accelerator is zeroed; and

a first command generator for generating a command to the second electric propulsion motor to drive the drive wheels with the clutch being commanded to be released when the vehicular velocity is below the predetermined value of the vehicular velocity and the manipulated variable of the accelerator is zeroed.

4. A vehicle as claimed in claim 2, wherein the controller includes:

a second determinator for determining whether the vehicular velocity is below a predetermined value of the vehicular velocity;

a third determinator for determining whether the discharge capacity of the battery supply is reduced; and

a second command generator for generating a command to supply the fuel to the engine to drive the engine and to set the clutch in an approximately semi-clutched state when the vehicular velocity is below the predetermined value of the vehicular velocity and the discharge capacity of the battery supply is reduced.

5. A vehicle as claimed in claim 2, wherein the controller includes:

a second determinator for determining whether the vehicular velocity is equal to or above a predetermined value of the vehicular velocity;

a third determinator for determining whether the manipulated variable of the accelerator is zeroed;

a fourth determinator for determining whether both or either of the charge and discharge capacities that the battery supply has are appropriate; and

a first command generator for generating a command to stop the fuel supply to the engine and to perform a regenerative power by means of the second electric propulsion motor so as to apply a regenerative braking through the second electric propulsion motor, the regenerated power and/or the charge power of the battery supply driving the third electric propulsion motor, when the vehicular velocity is equal to or above the predetermined value of the vehicular velocity with the manipulated variable of the accelerator zeroed and both or either of the charge and discharge capacities that the battery supply has are appropriate.

6. A vehicle as claimed in claim 5, wherein the charge-and-discharge capacity detector includes a battery temperature sensor for detecting a temperature of the battery supply and an SOC detecting device for detecting a state of charge of the battery supply and wherein the fourth determinator determines that either or both of the charge and discharge capacities that the battery supply has are appropriate when the temperature (Tb) of the battery supply falls in a predetermined range (Tb1≦

Tb≦

Tb2).

7. A vehicle as claimed in claim 5, wherein the charge-and-discharge capacity detector includes a battery temperature sensor for detecting a temperature of the battery supply and an SOC detecting device for detecting a state of charge of the battery supply and wherein the fourth determinator determines that both of the charge and discharge capacities that the battery supply has are appropriate when the state of charge in the battery supply falls in a predetermined range (SOC1≦

SOC≦

SOC2).

8. A vehicle as claimed in claim 5, wherein the controller includes:

a fifth determinator for determining whether the discharge capacity of the battery supply is reduced; and

a third command generator for generating a command to supply the fuel to the engine to be driven and to carry out the power generation through the first electric propulsion motor and for generating a command to perform the power generation through the first electric propulsion motor and to drive the third electric propulsion motor through the generated power and/or the regenerated power by the second propulsion motor, when the discharge capacity of the battery supply is reduced.

9. A vehicle as claimed in claim 8, wherein the charge-discharge capacity detector includes a temperature sensor for detecting a temperature of the battery supply and wherein the fifth determinator determines whether the discharge capacity of the battery supply is reduced depending upon whether the temperature of the battery supply falls out of a predetermined range of temperature.

10. A vehicle as claimed in claim 8, wherein the charge-and-discharge capacity detector includes a charge quantity state detector for detecting whether a charge quantity of the battery supply is equal to or below a predetermined value of the charge quantity and wherein the fifth determinator determines whether the discharge capacity of the battery supply is reduced depending upon whether the charge quantity is equal to or below the predetermined value of the charge quantity.

11. A vehicle as claimed in claim 5, wherein the controller includes:

a fifth determinator for determining whether a charge capacity that the battery supply has is reduced;

a fourth command generator for generating a command to stop the power generation by the second electric propulsion motor and to stop the supply of fuel to the engine with the clutch engaged when the charge capacity of the battery supply is reduced.

12. A vehicle as claimed in claim 11, wherein the charge-discharge capacity detector includes a charge quantity state detector for detecting whether a charge quantity of the battery supply is in excess of a predetermined value of the charge quantity and wherein the fifth determinator determines whether the charge capacity of the battery supply is reduced depending upon whether the charge quantity of the battery supply is in excess of the predetermined value of the charge quantity.

13. A vehicle as claimed in claim 2, wherein the controller includes a sixth command generator for generating a command to release the clutch and to reverse the second electric propulsion motor to backward the vehicle when the backward of the vehicle is selected through the operational member.

14. A vehicle as claimed in claim 13, wherein the controller includes:

a second determinator for determining whether the discharge capacity of the battery supply is reduced; and

a second command generator for generating a command to supply the fuel to the engine, to generate the power generation through the first electric propulsion motor, and to drive the second and third electric propulsion motors through the generated power by the first electric propulsion motor when the discharge capacity of the battery supply is reduced.

15. A vehicle as claimed in claim 2, wherein the operational member includes a selector lever position switch for detecting a selector lever is selected at which position of P, N, R, or D, the accelerator detector detects a depression depth θ

of an accelerator pedal, and the brake operation detector includes a brake switch for detecting whether a brake pedal is depressed.

16. A vehicle as claimed in claim 15, wherein the charge-and-discharge capacity detector includes a battery temperature sensor for detecting a temperature of the battery supply and an SOC detecting device for detecting a state of charge of the battery supply.

17. A vehicle as claimed in claim 15, which further comprises a key switch for activating the controller when it is at an ON position and wherein when the key switch is at an OFF position, the first propulsion motor is deactivated, the clutch is released, the second electric propulsion motor is deactivated, a speed ratio control of the continuously variable transmission is stopped, and the third electric propulsion motor is deactivated irrespective of any possible position of the selector lever, the depression depth or release of the accelerator pedal, and the depression or release of the brake pedal.

18. A vehicle as claimed in claim 17, wherein, when the key switch is placed at the ON position, the controller activates the third electric propulsion motor to supply working fluid of the hydraulic system of the continuously variable transmission irrespective of any possible position of the selector lever, the depression depth or release of the accelerator pedal, and the depression of the brake pedal.

19. A vehicle comprising:

clutch means having an input axle thereof and an output axle thereof;

an internal combustion engine for driving the input axle of the clutch means;

a first electric propulsion motor for driving the input axle of the clutch means;

a second electric propulsion motor for driving the output axle of the clutch means;

a continuously variable transmission having an input axle connected to the output axle of the clutch means via the second electric propulsion motor and an output axle connected to drive wheels of the vehicle;

a third electric propulsion motor for driving a hydraulic system of the continuously variable transmission;

a battery;

power inverting means for charging and discharging between the battery and the first, second, and third electric propulsion motors; and

controlling means for controlling operations of the engine, the power inverting means, the first, second, and third electric propulsion motors, and the continuously variable transmission.

20. A method applicable to a vehicle comprising:

providing a clutch having an input axle thereof and an output axle thereof;

providing an internal combustion engine for driving the input axle of the clutch;

providing a first electric propulsion motor for driving the input axle of the clutch;

providing a second electric propulsion motor for driving the output axle of the clutch;

providing a continuously variable transmission having an input axle connected to the output axle of the clutch via the second electric propulsion motor and an output axle connected to drive wheels of the vehicle;

providing a third electric propulsion motor for driving a hydraulic system of the continuously variable transmission;

providing a battery supply;

providing a power inverter for charging and discharging between the battery supply and the first, second, and third electric propulsion motors; and

controlling operations of the engine, the power inverter, the first, second, and third electric propulsion motors, and the continuously variable transmission.