Method for controlling an engine with an EGR system

• US 6,820,600 B1
• Filed: 10/15/2003
• Issued: 11/23/2004
• Est. Priority Date: 09/19/2002
• Status: Expired due to Fees

• Current Assignee: Detroit Diesel Corporation (Daimler Truck Holding AG)
• Original Assignee: Detroit Diesel Corporation (Daimler Truck Holding AG)
• Inventors: Sisken, Kevin Dean, Fan, Xuetong
• Primary Examiner(s): Miller, Carl S.
• Assistant Examiner(s): Castro, Arnold
• Application Number:
  US10/474,884
• Publication Number:
  US 20040236493A1
• Time in Patent Office: 405 Days
• Field of Search: 123/568.21, 123/568.12, 701/106, 701/108, 606/052
• US Class Current: 123/568.21
• CPC Class Codes: F02B 29/0406 Layout of the intake air cooling or coolant circuit
• CPC Class Codes: F02D 2200/0411 Volumetric efficiency
• CPC Class Codes: F02D 41/0072 Estimating, calculating or determining the EGR rate, amount or flow sensors in EGR systems F02M26/45
• CPC Class Codes: F02D 41/1405 Neural network control
• CPC Class Codes: F02D 41/18 by measuring intake air flow
• CPC Class Codes: F02M 26/02 EGR systems specially adapted for supercharged engines
• CPC Class Codes: F02M 26/23 Layout, e.g. schematics
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method for controlling an internal combustion engine (10) is provided. The engine (10) includes an exhaust gas recirculation (EGR) system (18, 20). The method includes determining an air mass flow rate through the intake manifold at a location upstream of the exhaust gas introduction, and determining an engine volumetric efficiency based on an engine speed and an intake manifold air density. An EGR flow rate is determined based on the volumetric efficiency, the intake manifold air density, an engine displacement volume, the engine speed, and the intake manifold air mass flow rate. The engine (10) is controlled based on the EGR flow rate. Preferred techniques for determining engine volumetric efficiency and EGR flow rate are also provided.

Claims

1. A method for controlling an internal combustion engine, the engine including an engine block defining a plurality of cylinders, an intake manifold for supplying air to the plurality of cylinders, a controller, and an exhaust gas recirculation (EGR) system, the EGR system introducing a metered portion of exhaust gases to the intake manifold, the controller communicating with the EGR system to control the engine, the method comprising:

determining an air mass flow rate through the intake manifold at a location upstream of the exhaust gas introduction;

determining an engine speed;

determining an intake manifold air density;

determining an engine volumetric efficiency based on the engine speed and the intake manifold air density;

determining an EGR flow rate based on the volumetric efficiency, the intake manifold air density, an engine displacement volume, the engine speed, and the intake manifold air mass flow rate; and

controlling the engine based on the EGR flow rate.

2. The method of claim 1 wherein determining the engine volumetric efficiency further comprises:

determining an engine exhaust to intake pressure ratio; and

determining a correction factor based on the engine exhaust to intake pressure ratio, wherein the engine volumetric efficiency is further based on the correction factor.

3. The method of claim 1 wherein determining the engine volumetric efficiency further comprises:

establishing a neural network that receives the engine speed, an intake manifold air pressure, an intake manifold air temperature, and an exhaust pressure as inputs, and provides the engine volumetric efficiency as an output.

4. The method of claim 1 wherein determining the EGR flow rate further comprises:

determining the EGR flow rate according to

5. An internal combustion engine, the engine including an engine block defining a plurality of cylinders, an intake manifold for supplying air to the plurality of cylinders, a controller, and an exhaust gas recirculation (EGR) system, the EGR system introducing a metered portion of exhaust gases to the intake manifold, the controller communicating with the EGR system to control the engine, the controller being programmed to control the internal combustion engine by:

determining an air mass flow rate through the intake manifold at a location upstream of the exhaust gas introduction;

determining an engine speed;

determining an intake manifold air density;

determining an engine volumetric efficiency based on the engine speed and the intake manifold air density;

determining an EGR flow rate based on the volumetric efficiency, the intake manifold air density, an engine displacement volume, the engine speed, and the intake manifold air mass flow rate; and

controlling the engine based on the EGR flow rate.

6. The engine of claim 5 wherein determining the engine volumetric efficiency further comprises:

determining an engine exhaust to intake pressure ratio; and

determining a correction factor based on the engine exhaust to intake pressure ratio, wherein the engine volumetric efficiency is fiercer based on the correction factor.

7. The engine of claim 5 wherein determining the engine volumetric efficiency further comprises:

establishing a neural network that receives the engine speed, an intake manifold air pressure, an intake manifold air temperature, and an exhaust pressure as inputs, and provides the engine volumetric efficiency as an output.

8. The engine of claim 5 wherein determining the EGR flow rate further comprises:

determining the EGR flow rate according to