Hybrid electric vehicle with limited operation strategy

• US 6,405,818 B1
• Filed: 04/11/2000
• Issued: 06/18/2002
• Est. Priority Date: 04/11/2000
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Anthony, Joseph William, Kuang, Ming Lang
• Primary Examiner(s): Swann, J. J.
• Assistant Examiner(s): Bottorff, Christopher
• Application Number:
  US09/546,831
• Time in Patent Office: 798 Days
• Field of Search: 180/65.1, 180/65.2, 180/65.3, 180/65.4, 180/65.8, 318/151, 318/153, 701/99, 701/101
• US Class Current: 180/65.8
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• 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 10/26 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 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: B60W 2050/021 Means for detecting failure or malfunction
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y10S 903/91 Orbital, e.g. planetary gears

Abstract

A hybrid electric vehicle 10 having a propulsion system 12 which includes an internal combustion engine 14, a generator/motor 16 and an electric motor or a “traction inverter module” 18 which cooperatively provide power to the drive train 28 of vehicle 10. Vehicle 10 includes a controller 44 which is effective to detect whether any faults are present within any of the torque providing subsystems (e.g., in engine 14, generator/motor 16 and/or motor 18), and if one or more faults is. present, to provide a limited operation strategy which allows the vehicle to be driveable by use of the remaining operational subsystem(s).

Claims

1. A method for limited operation of a hybrid electric vehicle of the type having an engine, a generator and a motor which are cooperatively coupled to and selectively provide torque to a drive line, said method comprising the steps of:

providing a controller which is effective to monitor said engine, said generator and said motor, and to selectively and controllably operate said vehicle by use of said engine, said generator and said motor;

determining whether a fault exists within said engine; and

causing said controller to operate in an LOS-electric drive mode if a fault exists within said engine, said controller being effective, while in said LOS-electric drive mode, to selectively operate said vehicle by use of only said motor and said generator.

2. The method of claim 1 further comprising the steps of:

determining an amount of torque which is desired to be provided to said drive line;

causing said controller to compare sa id amount of torque to a threshold value when said controller is operating in said LOS-electric drive mode; and

causing said controller to selectively operate said vehicle by use of only said motor if said amount of torque is less than said threshold value.

3. A method of claim 2 further comprising the steps of:

determining whether a fault exists within said generator; and

causing said controller to operate in an LOS-parallel drive mode if a fault exists within said generator, said controller being effective, while in said LOS-parallel drive mode, to selectively operate said vehicle by use of only said motor and said engine.

4. A method of claim 3 further comprising the steps of:

determining whether a fault exists within said generator; and

causing said controller to operate in an LOS-electric drive 1 mode if a fault exists within said engine and said generator, said controller being effective, while in said LOS-electric drive 1 mode, to selectively operate said vehicle by use of only said motor.

5. A method of claim 4 further comprising the step of:

causing said controller to operate in an LOS-electric drive 1 mode if a fault exists within said engine and said generator, said controller being effective, while in said LOS-electric drive 1 mode, to selectively operate said vehicle by use of only said motor.

6. A method of claim 5 further comprising the steps of:

determining whether a fault exists within said motor; and

causing said controller to operate in an LOS-hybrid drive mode if a fault exists within said motor, said controller being effective, while in said LOS-hybrid drive mode, to selectively operate said vehicle by use of only said generator and said engine.

7. A method for operating the powertrain of a hybrid electric vehicle in the presence of a faulty subsystem, said hybrid electric vehicle being of the type having an engine subsystem, a generator subsystem, and a motor subsystem which selectively and cooperatively provide torque to said powertrain, said method comprising the steps of:

selectively monitoring said engine subsystem, said generator subsystem, and said motor subsystem;

determining which of said engine subsystem, said generator subsystem and said motor subsystem are properly operational and which of said subsystems are faulty;

disabling any one of said subsystems which are faulty; and

operating said vehicle by use of only those two of said subsystems which are properly operational.

8. The method of claim 7 further comprising the step of:

operating said vehicle in a first mode if only in said engine subsystem is faulty, said first mode being effective to cause said vehicle to use only said generator subsystem and said motor subsystem to provide torque to said powertrain.

9. The method of claim 8 further comprising the step of:

operating said vehicle in a second mode if only said motor subsystem is faulty, said second mode being effective to cause said vehicle to use only said generator subsystem and said engine subsystem to provide torque to said powertrain.

10. The method of claim 9 further comprising the step of:

operating said vehicle in a third mode if only said generator subsystem is faulty, said third mode being effective to cause said vehicle to use only said motor subsystem and said engine subsystem to provide torque to said powertrain.

11. The method of claim 8 wherein said engine subsystem, said generator subsystem and said motor subsystem are cooperatively arranged in a power-split type configuration.

12. The method of claim 11 wherein said engine subsystem, said generator subsystem and said motor subsystem are interconnected by use of a planetary gear set.