System and method for controlling torque during engine start operations in hybrid vehicles

• US 8,499,734 B2
• Filed: 10/21/2009
• Issued: 08/06/2013
• Est. Priority Date: 10/21/2009
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Wang, Lan, Tamai, Goro, Pitsch, Michael J., Aldrich, William L. III
• Primary Examiner(s): Wolfe, Jr., Willis R
• Assistant Examiner(s): Bacon, Anthony L
• Application Number:
  US12/603,014
• Publication Number:
  US 20110088659A1
• Time in Patent Office: 1,385 Days
• Field of Search: 123/179.3, 123/179.4, 123/179.16, 123/179.18, 123/345, 123/347, 123/349, 123/350, 123/376, 701/113, 290/30.R, 290/38.R, 290/38.E
• US Class Current: 123/179.4
• CPC Class Codes: B60K 6/485 Motor-assist type
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2710/0605 Throttle position
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: F02D 2200/0406 Intake manifold pressure
• CPC Class Codes: F02D 2200/0414 Air temperature
• CPC Class Codes: F02D 2200/1004 Estimation of the output torque
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/062 for starting F02D41/061 takes precedence
• CPC Class Codes: F02N 11/0814 comprising means for controlling automatic idle-start-stop
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A control system for a hybrid vehicle that includes an internal combustion engine and an electric motor includes an engine speed control module, an air pressure control module, and an engine torque control module. The engine speed control module increases engine speed during a first calibration period based on a driver torque request and a predetermined torque threshold. The air pressure control module decreases intake manifold pressure (MAP) of the engine during a second calibration period based on the driver torque request and the predetermined torque threshold. The engine torque control module starts the engine during a period after the first and second calibration periods by activating N of M cylinders of the engine, wherein N is based on the driver torque request and the predetermined torque threshold.

Claims

1. A control system for a hybrid vehicle that includes an internal combustion engine and an electric motor, comprising:

an engine speed control module that increases engine speed during a first calibration period based on a driver torque request and a predetermined torque threshold;

an air pressure control module that decreases intake manifold pressure (MAP) of the engine during a second calibration period based on the driver torque request and the predetermined torque threshold; and

an engine torque control module that starts the engine during a period after the first and second calibration periods by activating N of M cylinders of the engine, wherein N is less than M at the end of the period when the driver torque request is less than the predetermined torque threshold.

2. The control system of claim 1, wherein the engine speed control module increases the engine speed to a first engine speed level when the driver torque request is less than the predetermined torque threshold, and that increases the engine speed to a second engine speed level when the driver torque request is greater than the predetermined torque threshold.

3. The control system of claim 2, wherein the second engine speed level is greater than the first engine speed level.

4. The control system of claim 1, wherein the engine speed control module increases the engine speed by using the electric motor to drive a crankshaft of the engine.

5. The control system of claim 4, wherein the electric motor drives the crankshaft of the engine one of directly, via a belt system, and via a planetary gearset.

6. The control system of claim 1, wherein the air pressure control module decreases the MAP to a predetermined MAP level by controlling a throttle.

7. The control system of claim 1, wherein N is equal to M at the end of the period when the driver torque request is greater than the predetermined threshold.

8. The control system of claim 1, wherein the engine torque control module enables valve actuation during the first calibration period, wherein the valve actuation occurs after the engine speed control module increases the engine speed and before the air pressure control module decreases the MAP.

9. The control system of claim 1, wherein the engine torque control module controls at least one of air, fuel, and spark supplied to the N cylinders based on the driver torque request.

10. The control system of claim 1, wherein the driver torque request is based on a position of an accelerator pedal of the vehicle.

11. A method for controlling a hybrid vehicle that includes an internal combustion engine and an electric motor, comprising:

increasing engine speed during a first calibration period based on a driver torque request and a predetermined torque threshold;

decreasing intake manifold pressure (MAP) of the engine during a second calibration period based on the driver torque request and the predetermined torque threshold; and

starting the engine during a period after the first and second calibration periods by activating N of M cylinders of the engine, wherein N is less than M at the end of the period when the driver torque request is less than the predetermined torque threshold.

12. The method of claim 11, further comprising:

increasing the engine speed to a first engine speed level when the driver torque request is less than the predetermined torque threshold; and

increasing the engine speed to a second engine speed level when the driver torque request is greater than the predetermined torque threshold.

13. The method of claim 12, wherein the second engine speed level is greater than the first engine speed level.

14. The method of claim 11, further comprising:

increasing the engine speed by using the electric motor to drive a crankshaft of the engine.

15. The method of claim 14, wherein the electric motor drives the crankshaft of the engine one of directly, via a belt system, and via a planetary gearset.

16. The method of claim 11, further comprising:

decreasing the MAP to a predetermined MAP level by controlling a throttle.

17. The method of claim 11, wherein N is equal to M at the end of the period when the driver torque request is greater than the predetermined threshold.

18. The method of claim 11, further comprising:

enabling valve actuation during the first calibration period, wherein the enabling occurs after the engine speed is increased and before the MAP is decreased.

19. The method of claim 11, further comprising:

controlling at least one of air, fuel, and spark supplied to the N cylinders based on the driver torque request.

20. The method of claim 11, wherein the driver torque request is based on a position of an accelerator pedal of the vehicle.