Throttle control systems and methods based on pressure ratio

• US 9,528,453 B2
• Filed: 02/09/2015
• Issued: 12/27/2016
• Est. Priority Date: 11/07/2014
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Whitney, Christopher E., Pochner, Klaus, Verdejo, Julian R.
• Primary Examiner(s): Gimie, Mahmoud
• Application Number:
  US14/617,068
• Publication Number:
  US 20160131061A1
• Time in Patent Office: 687 Days
• Field of Search: 701/101, 701/102, 701/103, 701/108, 123/319, 123/399, 123/402, 123/403, 123/480
• US Class Current: 1/1
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 2041/0017 by simultaneous control of throttle and exhaust gas recirculation
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/0077 Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position EGR valve position sensor F02M26/48
• CPC Class Codes: F02D 41/28 Interface circuits
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A torque requesting module generates a torque request for an engine based on driver input. A model predictive control (MPC) module: identifies sets of possible target values based on the torque request, each of the sets of possible target values including target pressure ratios across a throttle valve; determines predicted operating parameters for the sets of possible target values, respectively; determines cost values for the sets of possible target values, respectively; selects one of the sets of possible target values based on the cost values; and sets target values based on the possible target values of the selected one of the sets, respectively, the target values including a target pressure ratio across the throttle valve. A target area module determines a target opening area of the throttle valve based on the target pressure ratio. A throttle actuator module controls the throttle valve based on the target opening.

Claims

1. An engine control system of a vehicle, comprising:

a torque requesting module that generates a torque request for an engine based on driver input;

a model predictive control (MPC) module that;

identifies sets of possible target values based on the torque request, each of the sets of possible target values including target pressure ratios across a throttle valve;

determines predicted operating parameters for the sets of possible target values, respectively;

determines cost values for the sets of possible target values, respectively;

selects one of the sets of possible target values based on the cost values;

and

sets target values based on the possible target values of the selected one of the sets, respectively, the target values including a target pressure ratio across the throttle valve;

a target area module that determines a target opening area of the throttle valve based on the target pressure ratio; and

a throttle actuator module that controls the throttle valve based on the target opening.

2. The engine control system of claim 1 further comprising:

a target manifold absolute pressure (MAP) module that determines a target MAP based on the target pressure ratio and a throttle inlet air pressure (TIAP),

wherein the target area module determines the target opening area of the throttle valve based on the target MAP and the target pressure ratio.

3. The engine control system of claim 2 further comprising:

a target air per cylinder (APC) module that determines a target APC based on the target MAP and target intake and exhaust phase angles,

wherein the target area module determines the target opening area of the throttle valve based on the target APC and the target pressure ratio.

4. The engine control system of claim 3 further comprising:

a target mass air flowrate (MAF) module that determines a target MAF through the throttle valve based on the target APC,

wherein the target area module determines the target opening area of the throttle valve based on the target pressure ratio, the target MAF, and the TIAP.

5. The engine control system of claim 1 further comprising a conversion module that converts the target opening area into a target duty cycle,

wherein the throttle actuator module applies signals to the throttle valve based on the target duty cycle.

6. The engine control system of claim 1 further comprising a reference module that determines a reference pressure ratio across the throttle valve based on the torque request,

wherein the MPC module determines the cost values for the sets of possible target values based on differences between the possible target pressure ratios of the sets, respectively, and the reference pressure ratio.

7. The engine control system of claim 1 further comprising a target constraint module that outputs a maximum and a minimum pressure ratio across the throttle valve,

wherein the MPC module selects one of the sets of possible target values having possible target pressure ratios that are between the maximum and minimum pressure ratios.

8. The engine control system of claim 7 wherein the target constraint module sets the maximum pressure ratio across the throttle valve to a predetermined value.

9. The engine control system of claim 7 wherein the target constraint module sets the minimum pressure ratio across the throttle valve based on one or more engine operating parameters.

10. The engine control system of claim 1 wherein:

each of the sets of possible target values further includes possible target wastegate openings, possible target exhaust gas recirculation (EGR) valve openings, possible target intake phaser angles, and possible target exhaust phaser angles;

the target values further include a target wastegate opening, a target EGR valve opening, a target intake phaser angle, and a target exhaust phaser angle; and

the engine control system further includes;

a boost actuator module that controls opening of a wastegate associated with a turbocharger based on the target wastegate opening;

an EGR actuator module that controls opening of an EGR valve based on the target EGR valve opening; and

a phaser actuator module that controls intake and exhaust valve phasing based on the target intake and exhaust phaser angles, respectively.

11. An engine control method for a vehicle, comprising:

generating a torque request for an engine based on driver input;

using model predictive control (MPC);

identifying sets of possible target values based on the torque request, each of the sets of possible target values including target pressure ratios across a throttle valve;

determining predicted operating parameters for the sets of possible target values, respectively;

determining cost values for the sets of possible target values, respectively;

selecting one of the sets of possible target values based on the cost values; and

selecting target values based on the possible target values of the selected one of the sets, respectively, the target values including a target pressure ratio across the throttle valve;

determining a target opening area of the throttle valve based on the target pressure ratio; and

controlling the throttle valve based on the target opening.

12. The engine control method of claim 11 further comprising:

determining a target manifold absolute pressure (MAP) based on the target pressure ratio and a throttle inlet air pressure (TIAP); and

determining the target opening area of the throttle valve based on the target MAP and the target pressure ratio.

13. The engine control method of claim 12 further comprising:

determining a target air per cylinder (APC) based on the target MAP and target intake and exhaust phase angles; and

determining the target opening area of the throttle valve based on the target APC and the target pressure ratio.

14. The engine control method of claim 13 further comprising:

determining a target mass air flowrate (MAF) through the throttle valve based on the target APC; and

determining the target opening area of the throttle valve based on the target pressure ratio, the target MAF, and the TIAP.

15. The engine control method of claim 11 further comprising:

converting the target opening area into a target duty cycle; and

applying signals to the throttle valve based on the target duty cycle.

16. The engine control method of claim 11 further comprising:

determining a reference pressure ratio across the throttle valve based on the torque request; and

determining the cost values for the sets of possible target values based on differences between the possible target pressure ratios of the sets, respectively, and the reference pressure ratio.

17. The engine control method of claim 11 further comprising:

outputting a maximum and a minimum pressure ratio across the throttle valve; and

selecting one of the sets of possible target values having possible target pressure ratios that are between the maximum and minimum pressure ratios.

18. The engine control method of claim 17 further comprising setting the maximum pressure ratio across the throttle valve to a predetermined value.

19. The engine control method of claim 17 further comprising setting the minimum pressure ratio across the throttle valve based on one or more engine operating parameters.

20. The engine control method of claim 11 wherein:

each of the sets of possible target values further includes possible target wastegate openings, possible target exhaust gas recirculation (EGR) valve openings, possible target intake phaser angles, and possible target exhaust phaser angles;

the target values further include a target wastegate opening, a target EGR valve opening, a target intake phaser angle, and a target exhaust phaser angle; and

the engine control method further includes;

controlling opening of a wastegate associated with a turbocharger based on the target wastegate opening;

controlling opening of an EGR valve based on the target EGR valve opening; and

controlling intake and exhaust valve phasing based on the target intake and exhaust phaser angles, respectively.