Engine control system

Patent metadata

Field	Value
Publication number	US-11085380-B2
Application number	US-202016810155-A
Country	US
Kind code	B2
Filing date	Mar 5, 2020
Priority date	Sep 6, 2017
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

An engine control system includes: a delay estimating unit configured to estimate a auto-ignition delay based on first parameters including a composition of fuel gas; a auto-ignition predicting unit configured to predict a auto-ignition timing based on the auto-ignition delay; a completion predicting unit configured to predict a combustion completion timing of the fuel gas; and an operation control unit configured to control an engine based on a result of comparison between the auto-ignition timing and the combustion completion timing.

First claim

What is claimed is:

1. An engine control system, comprising:
a delay estimating unit configured to estimate an auto-ignition delay based on a composition of fuel gas, an in-cylinder pressure and an in-cylinder temperature;
an auto-ignition predicting unit configured to predict an auto-ignition timing based on the auto-ignition delay to provide a predicted auto-ignition timing;
a completion predicting unit configured to predict a combustion completion timing of the fuel gas to provide a predicted combustion completion timing; and
a control unit configured to make a comparison between the predicted auto-ignition timing and the predicted combustion completion timing, and to control an engine to perform an efficiency improvement control in response to a determination that the predicted auto-ignition timing does not precede the predicted combustion completion timing, and to perform a knocking suppression control in response to a determination that the predicted auto-ignition timing precedes the predicted combustion completion timing.

2. The engine control system according to claim 1 ,
wherein the delay estimating unit estimates the auto-ignition delay at each of a plurality of time points in a time period from start of fuel injection to auto-ignition, and
wherein the auto-ignition predicting unit predicts one of the time points, at which an integrated value of reciprocals of the auto-ignition delay becomes equal to or larger than 1, as the predicted auto-ignition timing.

3. The engine control system according to claim 2 , further comprising an in-cylinder variable acquiring unit configured to acquire the in-cylinder pressure and the in-cylinder temperature,
wherein the delay estimating unit estimates the auto-ignition delay in accordance with values of the in-cylinder pressure and values of the in-cylinder temperature at the plurality of time points.

4. The engine control system according to claim 3 , wherein the in-cylinder variable acquiring unit estimates the in-cylinder pressure and the in-cylinder temperature based on the composition of the fuel gas.

5. The engine control system according to claim 4 , wherein the completion predicting unit predicts the combustion completion timing based on one of a combustion speed of the fuel gas and the values of the in-cylinder pressure, and an injection amount of the fuel gas to provide the predicted combustion completion timing.

6. The engine control system according to claim 5 , wherein the control unit changes at least one of an intake temperature, an intake pressure, the injection amount of the fuel gas, a fuel injection timing, and a compression ratio.

7. The engine control system according to claim 4 , wherein the control unit changes at least one of an intake temperature, an intake pressure, an injection amount of the fuel gas, a fuel injection timing, and a compression ratio.

8. The engine control system according to claim 3 , wherein the completion predicting unit predicts the combustion completion timing based on one of a combustion speed of the fuel gas and the values of the in-cylinder pressure, and an injection amount of the fuel gas to provide the predicted combustion completion timing.

9. The engine control system according to claim 8 , wherein the control unit changes at least one of an intake temperature, an intake pressure, the injection amount of the fuel gas, a fuel injection timing, and a compression ratio.

10. The engine control system according to claim 3 , wherein the control unit changes at least one of an intake temperature, an intake pressure, an injection amount of the fuel gas, a fuel injection timing, and a compression ratio.

11. The engine control system according to claim 2 , wherein the control unit changes at least one of an intake temperature, an intake pressure, an injection amount of the fuel gas, a fuel injection timing, and a compression ratio.

12. The engine control system according to claim 1 , wherein the control unit changes at least one of an intake temperature, an intake pressure, an injection amount of the fuel gas, a fuel injection timing, and a compression ratio.

13. The engine control system according to claim 1 , further comprising an in-cylinder variable acquiring unit configured to acquire the in-cylinder pressure value at a plurality of time points and the in-cylinder temperature value at the plurality of time points;
wherein the delay estimating unit estimates the auto-ignition delay in accordance with the in-cylinder pressure values and the in-cylinder temperature values; and
wherein the completion predicting unit predicts the combustion completion timing as a time at which an integrated heat generation amount exceeds a threshold value to provide the combustion completion timing.

14. The engine control system according to claim 1 , wherein the efficiency improvement control includes at least one of advancing ignition timing or increasing compression ratio; and
wherein the knocking suppression control includes at least one of decreasing compression ratio, delaying ignition timing, increasing intake pressure, or decreasing intake temperature.

Assignees

• Ihi Corp

Inventors

• Masuda Yutaka
• Aoyagi Takahide
• Hirose Takayuki
• Yamada Takayuki
• Nakajima Hayato

Classifications

• F02D35/024

  using an estimation · CPC title

• F02D35/028 Primary

  by determining the combustion timing or phasing · CPC title

• F02D45/00

  Electrical control not provided for in groups F02D41/00 - F02D43/00 · CPC title

• F02D19/029 Primary

  Determining density, viscosity, concentration or composition · CPC title

• F02D19/02 Primary

  peculiar to engines working with gaseous fuels · CPC title