Method of controlling engine, and engine system

Patent metadata

Field	Value
Publication number	US-11859574-B2
Application number	US-202117452345-A
Country	US
Kind code	B2
Filing date	Oct 26, 2021
Priority date	Nov 10, 2020
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

A method of controlling an engine is provided, which includes the steps of injecting main fuel by a fuel injector during an intake stroke or a compression stroke, providing a mixture gas containing fuel and air inside a cylinder, applying by an ignition device a high voltage between electrodes of a spark plug at a timing when the mixture gas is not ignited, detecting a parameter related to a current value of an electric-discharge channel generated between the electrodes, determining by a controller whether the detected parameter is within a range between a first threshold and a second threshold to determine a flowing state of a vortex inside the cylinder, operating the spark plug to carry out a supplemental ignition when the parameter is determined to be outside the range, and igniting the mixture gas by operation of the spark plug after the supplemental ignition.

First claim

What is claimed is:

1. A method of controlling an engine by using a controller, the engine including a cylinder with a pentroof ceiling, air being introduced into the cylinder through an intake valve provided to the ceiling; an ignition device including a spark plug provided at or near the center axis of the cylinder; and a fuel injector provided at or near the center axis of the cylinder, the method comprising the steps of:
injecting main fuel by the fuel injector during one of an intake stroke and a compression stroke, and providing a mixture gas containing fuel and air inside the cylinder;
applying by the ignition device a high voltage between electrodes of the spark plug at a timing when the mixture gas is not ignited, and detecting a parameter related to a current value of an electric-discharge channel generated between the electrodes;
determining by the controller whether the detected parameter is within a range between a first threshold and a second threshold to determine a flowing state of a vortex inside the cylinder;
when the parameter is determined to be outside the range, operating the spark plug to perform a supplemental ignition to generate hot plasma prior to a main ignition, and to perform the main ignition to ignite the mixture gas after the supplemental ignition; and
when the parameter is determined to be within the range, operating the spark plug to perform only the main ignition to ignite the mixture gas.

2. The method of claim 1 , wherein the operating the spark plug includes, when the parameter is determined to be below the first threshold, operating the spark plug at a first operation timing, and when the parameter is determined to be above the second threshold, operating the spark plug at a second operation timing retarded from the first operation timing.

3. The method of claim 2 ,
wherein the applying the high voltage includes detecting the parameter by the ignition device at a timing between an opening of the intake valve and a closing of the intake valve, and
wherein the determining whether the detected parameter is within the range includes determining by the controller a flowing state of a swirl vortex inside the cylinder based on the parameter.

4. The method of claim 3 , wherein the applying the high voltage includes detecting the parameter by the ignition device after a given time constant passes from the opening of the intake valve.

5. The method of claim 2 ,
wherein the applying the high voltage includes detecting the parameter by the ignition device after the closing of the intake valve, and
wherein the determining whether the detected parameter is within the range includes determining by the controller a flowing state of a tumble vortex inside the cylinder based on the parameter.

6. The method of claim 2 , wherein the applying the high voltage includes detecting the parameter by the ignition device during the intake stroke and during the compression stroke.

7. An engine system, comprising:
an engine including:
a cylinder with a pentroof ceiling, air being introduced into the cylinder through an intake valve provided to the ceiling;
an ignition device including a spark plug provided at or near the center axis of the cylinder; and
a fuel injector provided at or near the center axis of the cylinder; and

a controller electrically connected to the ignition device and the fuel injector,
wherein the controller includes a processor configured to execute:
a main fuel injection module to control the fuel injector to inject main fuel during one of an intake stroke and a compression stroke, and provide a mixture gas containing fuel and air inside the cylinder;
a determination module to control the ignition device to apply a high voltage between electrodes of the spark plug at a timing when the mixture gas is not ignited, and detect a parameter related to a current value of an electric-discharge channel generated between the electrodes, and to determine whether the parameter detected by the ignition device is within a range between a first threshold and a second threshold to determine a flowing state of a vortex inside the cylinder;
a supplemental ignition control module to control the ignition device to operate the spark plug to generate hot plasma; and
a main ignition control module to control the ignition device to operate the spark plug to ignite the mixture gas by the spark plug after the supplemental ignition control module operates the spark plug, wherein

when the determination module determines the parameter is outside the range, the spark plug is operated to perform a supplemental ignition to generate the hot plasma prior to a main ignition, and to perform the main ignition to ignite the mixture gas after the supplemental ignition, and
when the determination module determines the parameter is within the range, the spark plug is operated to perform only the main ignition to ignite the mixture gas.

8. The engine system of claim 7 , wherein when the determination module determines that the parameter is below the first threshold, the spark plug operates at a first operation timing, and when the determination module determines that the parameter is above the second threshold, the spark plug operates at a second operation timing retarded from the first operation timing.

9. The engine system of claim 8 ,
wherein the ignition device detects the parameter at a timing between an opening of the intake valve and a closing of the intake valve, and
wherein the controller determines a flowing state of a swirl vortex inside the cylinder based on the parameter.

10. The engine system of claim 9 , wherein the ignition device detects the parameter after a given time constant passes from the opening of the intake valve.

11. The engine system of claim 8 ,
wherein the ignition device detects the parameter after the closing of the intake valve, and
wherein the controller determines a flowing state of a tumble vortex inside the cylinder based on the parameter.

12. The engine system of claim 8 , wherein the ignition device detects the parameter during the intake stroke and during the compression stroke.

13. The method of claim 1 ,
wherein the applying the high voltage includes detecting the parameter by the ignition device at a timing between an opening of the intake valve and a closing of the intake valve, and
wherein the determining whether the detected parameter is within the range includes determining by the controller a flowing state of a swirl vortex inside the cylinder based on the parameter.

14. The method of claim 1 ,
wherein the applying the high voltage includes detecting the parameter by the ignition device after the closing of the intake valve, and
wherein the determining whether the detected parameter is within the range includes determining by the controller a flowing state of a tumble vortex inside the cylinder based on the parameter.

15. The method of claim 1 , wherein the applying the high voltage includes detecting the parameter by the ignition device during the intake stroke and during the compression stroke.

16. The engine system of claim 7 ,
wherein the ignition device detects the parameter at a timing between an opening of the intake valve and a closing of the intake valve, and
wherein the controller determines a flowing state of a swirl vortex inside the cylinder based on the parameter.

17. The engine system of claim 7 ,
wherein the ignition device detects the parameter after the closing of the intake valve, and
wherein the controller determines a flowing state of a tumble vortex inside the cylinder bas

Assignees

• Mazda Motor

Inventors

• Ota Noriyuki
• Nou Yoshihisa

Classifications

• F02D41/402 Primary

  Multiple injections · CPC title

• F02F1/24

  Cylinder heads · CPC title

• F02P3/06

  having capacitive energy storage (piezoelectric or electrostatic ignition F02P3/12) · CPC title

• F02P5/1502

  using one central computing unit · CPC title

• F02D2041/389

  for injecting directly into the cylinder · CPC title