Hybrid electric vehicle and a method for operating a hybrid electric vehicle

• US 6,688,411 B2
• Filed: 11/09/2001
• Issued: 02/10/2004
• Est. Priority Date: 11/09/2001
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Peters, Mark William, Deniston, Paul Michael, Robichaux, Jerry D., Kotre, Stephen John, Boggs, David Lee
• Primary Examiner(s): Johnson, Brian L.
• Assistant Examiner(s): Swenson, Brian L
• Application Number:
  US09/683,026
• Publication Number:
  US 20030089538A1
• Time in Patent Office: 823 Days
• Field of Search: 180/65.1, 180/65.2, 123/350, 123/352, 123/357, 701/110
• US Class Current: 180/65.235
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• 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 2240/445 Temperature
• 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 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2050/021 Means for detecting failure or malfunction
• CPC Class Codes: B60W 2510/068 Engine exhaust temperature
• CPC Class Codes: B60W 2710/065 Idle condition
• CPC Class Codes: F02D 41/062 for starting F02D41/061 takes precedence
• CPC Class Codes: F02D 41/405 with post injections
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/91 Orbital, e.g. planetary gears

Abstract

A hybrid electric vehicle 10 and a method for operating the hybrid electric vehicle 10 in which combustion is made to occur within the internal combustion engine 24 only after the crankshaft 25 of the engine 24 has been rotated by an electric motor or generator 30 to a certain speed and according to a certain ramped or partially ramped profile 114, 112, thereby reducing the amount of emissions from the engine 24, allowing for a more efficient torque transfer to wheels 42, and allowing for a more smoother operation of the vehicle 10. The fuel injectors 13, throttle plate 11, and spark plugs 15 are also controlled in order to allow emissions to be reduced during activation of the engine and to allow the catalytic converter 7 to be heated in order to allow these emissions to be further reduced as the engine 24 is operating.

Claims

1. A hybrid electric vehicle, comprising:

an engine;

a motor;

a disconnect clutch disposed between the engine and the motor for selectively connecting the engine to, and disconnecting the engine from, the motor; and

a controller configured to command the motor to rotate the engine, thereby increasing engine speed over time and generating an engine speed profile, the controller being further configured to determine whether the engine speed profile matches a predetermined ideal speed profile, provide fuel to the engine when the engine speed reaches a target speed and the engine speed profile matches the predetermined ideal speed profile, and provide fuel to the engine before the engine speed reaches the target speed when the engine speed profile does not match the predetermined ideal speed profile.

2. The hybrid electric vehicle of claim 1, wherein the controller is further configured to determine whether the engine speed has reached a predetermined minimum speed, and to provide fuel to the engine only when the engine speed is greater than the predetermined minimum speed, the predetermined minimum speed being the engine speed necessary to sustain engine combustion.

3. The vehicle of claim 1, wherein the ideal speed profile is characterized by a line having a constant, positive slope.

4. The vehicle of claim 1, wherein the controller is further configured to determine whether the engine speed has reached a predetermined minimum speed, and to provide fuel to the engine only when the engine speed is greater than the predetermined minimum speed, the predetermined minimum speed being the engine speed necessary to sustain engine combustion.

5. The vehicle of claim 1, wherein the controller is further configured to calculate a rate of change of the engine speed over a predetermined time interval and to compare the calculated rate of change to a rate of change for the ideal speed profile, thereby determining whether the engine speed profile matches the ideal speed profile.

6. The vehicle of claim 1, wherein the ideal speed profile is a predetermined function of time, and wherein the controller is further configured to compare a point on the engine speed profile to an expected speed, the expected speed being determined from the ideal speed profile.

7. The vehicle of claim 1, wherein the controller comprises:

an engine control unit for controlling the engine, and connected to the engine through a hardwire interface;

a transaxle management unit for controlling the motor, and connected to the motor through a hardwire interface; and

a vehicle system controller in communication with the engine control unit and the transaxle management unit.

8. The vehicle of claim 7, further comprising a catalytic converter, and wherein the engine includes spark plugs, fuel injectors, and a throttle plate, and wherein the engine control unit is configured with an emission minimizing control routine for facilitating a reduction in exhaust emissions by rapidly heating the catalytic converter, the emission minimizing control routine including controlling spark timing, throttle plate position, and an amount of fuel provided to the engine.