Control device for internal combustion engine and control method for internal combustion engine

Patent metadata

Field	Value
Publication number	US-2019293003-A1
Application number	US-201716316538-A
Country	US
Kind code	A1
Filing date	Jun 29, 2017
Priority date	Jul 14, 2016
Publication date	Sep 26, 2019
Grant date	—

Abstract

An internal combustion engine in which when the gas temperature of a fuel reformation chamber when a piston in a fuel reformation cylinder reaches the compression top dead point is estimated to be equal to or higher than a soot generation lower limit temperature set according to an equivalence ratio of the fuel reformation chamber, a reaction gas temperature adjusting operation for suppressing or reducing an increase in the reaction gas temperature in the fuel reformation chamber is executed. Further, a closing timing of an air-intake valve is changed to reduce an effective compression ratio of the fuel reformation chamber.

First claim

1 . A control device for an internal combustion engine including a fuel reformation cylinder and an output cylinder to which reformed fuel generated in the fuel reforming cylinder is supplied, the output cylinder being configured to yield an engine power by combusting the reformed fuel, the control device comprising:
a reaction gas temperature adjustment unit configured to adjust a reaction gas temperature in the fuel reformation cylinder according to an equivalence ratio in the fuel reformation cylinder so that the equivalence ratio and the reaction gas temperature in the fuel reformation cylinder at a time of fuel reformation are in a reforming reaction possible range but outside a soot generation range, the soot generation range being defined by the equivalence ratio and the reaction gas temperature in the fuel reformation cylinder.

2 . The control device according to claim 1 , wherein:
the reaction gas temperature adjustment unit is configured to change a control amount of a control to suppress or reduce an increase in the reaction gas temperature of the fuel reformation cylinder caused by the equivalence ratio of the fuel reformation cylinder dropping to approach 1, and configured to increase the control amount as the equivalence ratio of the fuel reformation cylinder approaches 1.

3 . The control device according to claim 1 , wherein:
the reaction gas temperature adjustment unit is configured to adjust the reaction gas temperature in the fuel reformation cylinder by adjusting at least one of an amount of exhaust gas from the output cylinder recirculated to the fuel reformation cylinder and the temperature of the exhaust gas recirculated.

4 . The control device according to claim 1 , wherein:
the reaction gas temperature adjustment unit is configured to adjust the reaction gas temperature in the fuel reformation cylinder, by adjusting an effective compression ratio of the fuel reformation cylinder.

5 . The control device according to claim 2 , wherein
the fuel reforming operation in the fuel reformation cylinder is not executed, even when the control amount of the control to suppress or reduce an increase in the reaction gas temperature in the fuel reformation cylinder reaches a limit value of a controllable range, if the equivalence ratio and the reaction gas temperature of the fuel reformation cylinder at the time of fuel reformation are estimated to be in the soot generation range.

6 . A control method for an internal combustion engine including a fuel reformation cylinder and an output cylinder to which reformed fuel generated in the fuel reforming cylinder is supplied, the output cylinder being configured to yield an engine power by combusting the reformed fuel, wherein:
the method adjusts a reaction gas temperature in the fuel reformation cylinder according to an equivalence ratio in the fuel reformation cylinder so that the equivalence ratio and the reaction gas temperature in the fuel reformation cylinder at a time of fuel reformation are in a reforming reaction possible range but outside a soot generation range, the soot generation range being defined by the equivalence ratio and the reaction gas temperature in the fuel reformation cylinder.

Assignees

• Yanmar Co Ltd

Inventors

• Asai Go

Classifications

• B01J19/0013

  Controlling the temperature of the process · CPC title

• F02B51/02

  involving catalysts · CPC title

• F02D41/0025

  Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures · CPC title

• B01J19/0026

  Avoiding carbon deposits (inhibiting incrustation in general, C23F14/00, C23F15/00) · CPC title

• F02M27/02

  by catalysts · CPC title