Method for controlling a high pressure gas injection internal combustion engine

Patent metadata

Field	Value
Publication number	US-10753274-B2
Application number	US-201515781131-A
Country	US
Kind code	B2
Filing date	Dec 7, 2015
Priority date	Dec 7, 2015
Publication date	Aug 25, 2020
Grant date	Aug 25, 2020

Abstract

A method of controlling a high pressure gas injection internal combustion engine includes injecting, in a first combustion mode, by a first as injection system, a first gaseous fuel into a cylinder of the engine, and accumulating in a container of a second gas injection system excess gaseous fuel from the first fuel system, shifting, in the cylinder, from the first combustion mode to a second combustion mode including determining a value of an air flow related parameter indicative of an air mass flow into the cylinder, determining, based on the determined air flow related parameter value, a value of a fuel flow related parameter indicative of a mass flow of the excess gaseous fuel, and supplying from the container, in accordance with the determined fuel flow related parameter value, the excess gaseous fuel to provide a premix of air and the excess gaseous fuel to the cylinder.

First claim

The invention claimed is:

1. A method of controlling a diesel type high pressure gas injection internal combustion engine, the method comprising
injecting, in a first combustion mode, by means of a first gas injection system, a first gaseous fuel into a cylinder of the engine, the step of injecting the first gaseous fuel comprising injecting the first gaseous fuel after a crankshaft angle of 90 degrees before a top dead centre position at the end of a compression stroke of the cylinder,
accumulating in a container of a second gas injection system excess gaseous fuel from the first fuel system, and
shifting, in the cylinder, from the first combustion mode to a second combustion mode comprising
determining a value of an air flow related parameter indicative of an air mass flow into the cylinder,
wherein the second combustion mode further comprises determining, based on the determined air flow related parameter value, a value of a fuel flow related parameter indicative of a mass flow of the excess gaseous fuel, and
supplying from the container, in accordance with the determined fuel flow related parameter value, the excess gaseous fuel to provide a premix of air and the excess gaseous fuel to the cylinder,
wherein the premix has a lambda value of 1.3-1.7.

2. A method according to claim 1 , wherein the step of supplying the excess gaseous fuel comprises injecting the excess gaseous fuel into the cylinder or into a conduit arranged to guide air to the cylinder.

3. A method according to claim 2 , wherein the step of injecting the first gaseous fuel comprises injecting the first gaseous fuel at a first pressure, and the step of injecting the excess gaseous fuel comprises injecting the excess gaseous fuel at a second pressure which is lower than the first pressure.

4. A method according to claim 2 , wherein the step of injecting the excess gaseous fuel comprises injecting the excess gaseous fuel before a crankshaft angle of 90 degrees before a top dead centre position at the end of a compression stroke of the cylinder.

5. A method according to claim 1 , wherein the second combustion mode comprises a pilot injection of a liquid fuel.

6. A method according to claim 1 , wherein the step of injecting the first gaseous fuel comprises injecting the first gaseous fuel by means of a first injector, and the second combustion mode comprises a pilot injection of the first gaseous fuel by means of the first injector.

7. A method according to claim 1 , comprising, simultaneously to the step of supplying the excess gaseous fuel to provide a premix of air and the excess gaseous fuel to the cylinder, injecting, in the first combustion mode, by means of the first gas injection system, the first gaseous fuel into a further cylinder of the engine, the further cylinder being a first cylinder, and the cylinder in which the combustion mode is shifted from the first combustion mode to the second combustion mode being a second cylinder.

8. A method according to claim 1 , comprising determining a required load of the engine, and by controlling the injection, in the first combustion mode, of the first gaseous fuel into the first cylinder so as to provide a total load of the engine corresponding to the required load.

9. A method according to claim 8 , wherein the load in the second cylinder corresponds to a load in an interval of 50-70% of a full load in the second cylinder.

10. A method according to claim 1 , comprising determining a pressure or gas content in the container,
and performing the shift from the first combustion mode to the second combustion mode in dependence on the determined pressure or gas content in the container.

11. A method according to claim 10 , comprising performing the shift on the condition that the pressure or gas content in the second container is above a threshold value.

12. A computer comprising a computer program for performing the steps of claim 1 when the program is run on the computer.

13. A non-transitory computer readable medium carrying a computer program for performing the steps of claim 1 when the program is run on a computer.

14. A control unit being arranged to perform the steps of the method according claim 1 .

Assignees

• Volvo Truck Corp

Inventors

• Magnusson Ingemar
• Andersson Arne
• Andersson Lennart

Classifications

• F02D41/401

  Controlling injection timing (F02D41/402 takes precedence) · CPC title

• F02M21/0245

  High pressure fuel supply systems; Rails; Pumps; Arrangement of valves · CPC title

• F02D41/403

  with pilot injections · CPC title

• F02M21/0215

  Mixtures of gaseous fuels; Natural gas; Biogas; Mine gas; Landfill gas · CPC title

• F02D41/3094

  the fuel injection being effected by at least two different injectors, e.g. one in the intake manifold and one in the cylinder · CPC title