Control device and control method for internal combustion engine

Patent metadata

Field	Value
Publication number	US-9291141-B2
Application number	US-201414220699-A
Country	US
Kind code	B2
Filing date	Mar 20, 2014
Priority date	Oct 17, 2013
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

Provided is a control device for an internal combustion engine, which enables enlargement of an operation region in which homogenous-charge compression ignition combustion enabling the generation of NOx to be suppressed and fuel efficiency to be improved can be performed. An ignition-timing control section ( 23 ) continuously and repeatedly controls an ignition timing to a retard side when a first combustion-state index reaches a predefined predetermined upper limit value of the first combustion-state index and controls the ignition timing to an advance side when a second combustion-state index reaches a predefined predetermined upper limit value of the second combustion-state index.

First claim

What is claimed is:

1. A control device for an internal combustion engine including an ignition device provided in a combustion chamber, the ignition device being configured to ignite an air/fuel mixture formed in the combustion chamber, the internal combustion engine being configured to combust a part of the air/fuel mixture, which is located in areas other than in vicinity of the ignition device, by homogenous-charge compression ignition combustion using an increase in temperature, which is caused by combusting a part of the air/fuel mixture in the vicinity of the ignition device with spark ignition, and an increase in temperature caused by a combustion pressure, the control device comprising:
a combustion-state detecting section for detecting a first combustion-state index relating to a combustion state brought about by the air/fuel mixture at a high temperature and a second combustion-state index relating to a combustion state brought about by the air/fuel mixture at a low temperature; and
an ignition-timing control section for controlling an ignition timing based on the first combustion-state index and the second combustion-state index,
the ignition-timing control section being configured to continuously and repeatedly control the ignition timing to a retard side when the first combustion-state index reaches a predefined predetermined upper limit value of the first combustion-state index and control the ignition timing to an advance side when the second combustion-state index reaches a predefined predetermined upper limit value of the second combustion-state index.

2. A control device for an internal combustion engine according to claim 1 , wherein the combustion-state detecting section detects a combustion-state quantity relating to pre-ignition corresponding to an advanced self-ignition timing as the first combustion-state index.

3. A control device for an internal combustion engine according to claim 1 , wherein the combustion-state detecting section detects a combustion-state quantity relating to slow combustion corresponding to a low combustion speed as the second combustion-state index.

4. A control device for an internal combustion engine according to claim 1 , wherein the combustion-state detecting section detects a combustion-state quantity relating to rapid combustion corresponding to a high combustion speed as the first combustion-state index.

5. A control device for an internal combustion engine according to claim 1 , wherein the combustion-state detecting section detects a combustion-state quantity relating to a combustion fluctuation corresponding to destabilized combustion as the second combustion-state index.

6. A control device for an internal combustion engine according to claim 1 , wherein the ignition-timing control section sets a correction amount for the ignition timing to be larger immediately after switching between retard control and advance control than in other cases.

7. A control device for an internal combustion engine according to claim 1 , wherein the ignition-timing control section provides an advance limit and a retard limit to the ignition timing and controls the ignition timing within a range between the advance limit and the retard limit.

8. A control device for an internal combustion engine according to claim 1 , wherein the ignition-timing control section stops the spark ignition when the first combustion-state index exceeds the predetermined upper limit value of the first combustion-state index by a predefined predetermined number of cycles.

9. A control method for an internal combustion engine including an ignition device provided in a combustion chamber, the ignition device being configured to ignite an air/fuel mixture formed in the combustion chamber, the internal combustion engine being configured to combust apart of the air/fuel mixture, which is located in areas other than in vicinity of the ignition device, by homogenous-charge compression ignition combustion using an increase in temperature, which is caused by combusting apart of the air/fuel mixture in the vicinity of the ignition device with spark ignition, and an increase in temperature caused by a combustion pressure, the control method comprising:
detecting a first combustion-state index relating to a combustion state brought about by the air/fuel mixture at a high temperature and a second combustion-state index relating to a combustion state brought about by the air/fuel mixture at a low temperature; and
controlling an ignition timing based on the first combustion-state index and the second combustion-state index,
the controlling an ignition timing comprising continuously and repeatedly executing processing of controlling the ignition timing to a retard side when the first combustion-state index reaches a predefined predetermined upper limit value of the first combustion-state index and controlling the ignition timing to an advance side when the second combustion-state index reaches a predefined predetermined upper limit value of the second combustion-state index.

Assignees

• Mitsubishi Electric Corp

Inventors

• Kawakami Teruaki

Classifications

• F02D41/3041 Primary

  with means for triggering compression ignition, e.g. spark plug · CPC title

• F02P5/153

  dependent on combustion pressure · CPC title

• F02P5/152

  dependent on pinking (detecting or indicating knocks in internal-combustion engines G01L23/22) · CPC title

• F02D35/028

  by determining the combustion timing or phasing · CPC title

• F02D35/023

  by determining the cylinder pressure · CPC title