Control system for a dual-fuel engine

Patent metadata

Field	Value
Publication number	US-9334813-B2
Application number	US-201313755588-A
Country	US
Kind code	B2
Filing date	Jan 31, 2013
Priority date	Jan 31, 2013
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

A control system for a dual-fuel engine is disclosed. The control system may have a gaseous fuel injector having a nozzle located at a first air intake port of a cylinder of the engine and configured to inject a variable amount of gaseous fuel radially into the cylinder based on at least one of a load and speed of the engine. The control system may also have a liquid fuel injector configured to inject a fixed amount of liquid fuel axially into the cylinder based on the at least one of the load and speed of the engine. The control system may additionally have a regulator configured to selectively adjust a flow of gaseous fuel to the gaseous fuel injector and at least one sensor configured to generate a signal indicative of a performance parameter of the engine. The control system may also have a controller in communication with the regulator and the at least one sensor. The controller may be configured to selectively cause the regulator to adjust the flow of gaseous fuel based on the signal.

First claim

What is claimed is:

1. A control system for a dual-fuel engine, comprising:
a gaseous fuel injector having a nozzle located at a first air intake port of a cylinder of the engine and configured to inject a variable amount of gaseous fuel radially into the cylinder based on at least one of a load and a speed of the engine;
a liquid fuel injector configured to inject a fixed amount of liquid fuel axially into the cylinder based on the at least one of the load and the speed of the engine;
a regulator configured to selectively adjust a flow of gaseous fuel to the gaseous fuel injector;
at least one sensor positioned at a second air intake port of the cylinder and configured to generate a first signal indicative of a first performance parameter of the engine wherein the first performance parameter is a presence of gaseous fuel that has exited the cylinder through a second air intake port; and
a controller in communication with the regulator and the at least one sensor, the controller being configured to selectively cause the regulator to adjust the flow of gaseous fuel based on the signal.

2. The control system of claim 1 , wherein the at least one sensor is configured to generate a second signal indicative of a second performance parameter of the engine, wherein the second performance parameter is a pressure of air entering the cylinder through the second air intake port.

3. The control system of claim 1 , wherein the gaseous fuel contributes about 40-85% of a total energy produced by fuel combustion inside the cylinder.

4. The control system of claim 3 , wherein the gaseous fuel contributes about 60-65% of the total energy produced by fuel combustion.

5. The control system of claim 1 , wherein the liquid fuel injector is mechanically driven in a cyclical manner.

6. The control system of claim 1 , wherein the controller is configured to maintain a downstream injection pressure of fuel entering the cylinder at approximately 0.5-4 bar greater than a pressure of air entering the cylinder through the second air intake port.

7. The control system of claim 1 , wherein the performance parameter is a presence of an exhaust constituent above a threshold level.

8. The control system of claim 1 , wherein the performance parameter is frequency of a pressure wave created by fuel combustion.

9. The control system of claim 1 , wherein the gaseous fuel injector is configured to begin and end a gaseous fuel injection during a time period in which the first air intake port is open.

10. The control system of claim 9 , wherein the liquid fuel injector is configured to begin a liquid fuel injection after the end of the gaseous fuel injection.

11. A method of controlling operation of a dual-fuel engine, comprising:
injecting a variable amount of gaseous fuel radially through a first air intake port of a cylinder of the engine based on at least one of a load and speed of the engine;
injecting a fixed amount of liquid fuel axially into the cylinder based on the at least one of the load and speed of the engine;
sensing a first performance parameter of the engine wherein the first performance parameter is a presence of gaseous fuel that has exited the cylinder through a second air intake port; and
selectively adjusting the amount of gaseous fuel injected based on the performance parameter.

12. The method of claim 11 , further comprising: sensing a second performance parameter of the engine, wherein the second performance parameter is a pressure of air entering the cylinder through a second air intake port.

13. The method of claim 11 , wherein adjusting gaseous fuel injection includes adjusting a pressure of gaseous fuel injected into the cylinder to a pressure that is about 0.5-4 bar greater than a pressure of air entering the cylinder.

14. The method of claim 11 , wherein injecting the gaseous fuel includes injecting the gaseous fuel for about 25-40% of a time period during which the first air intake port is open.

15. The method of claim 14 , wherein injecting the gaseous fuel includes injecting the gaseous fuel during a second half of the time period during which the first air intake port is open.

16. The method of claim 11 , wherein injecting the variable amount of gaseous fuel includes directing gaseous fuel through a converging nozzle configured to choke the flow of gaseous fuel.

17. The method of claim 11 , wherein the gaseous fuel contributes about 40-85% of a total energy produced by fuel combustion inside the cylinder.

18. The method of claim 17 , wherein the gaseous fuel contributes about 60-65% of the total energy produced by fuel combustion.

19. The method of claim 11 , wherein the performance parameter is a presence of an exhaust constituent above a threshold level.

20. The method of claim 11 , wherein the performance parameter is a frequency of a pressure wave created by fuel combustion.

21. A dual-fuel engine, comprising:
an engine block defining a plurality of cylinders;
an air box connected to a side of the engine block;
a cylinder liner disposed in each of the plurality of cylinders and having a plurality of air intake ports;
a cylinder head associated with each of the plurality of cylinders;
a piston disposed within each of the plurality of cylinders;
a combustion chamber at least partially defined by the cylinder liner, the cylinder head, and the piston;
a gaseous fuel injector having a nozzle located at a first air intake port of each of the plurality of cylinders and configured to inject a variable amount of gaseous fuel radially through the air intake port based on at least one of a load and a speed of the engine;
a liquid fuel injector configured to inject a fixed amount of liquid fuel axially into the cylinder based on at least one of the load and the speed of the engine;
a regulator configured to selectively adjust a flow of gaseous fuel to the gaseous fuel injector;
at least one sensor positioned at a second air intake port of the cylinder and configured to generate a signal indicative of a performance parameter of the engine wherein the performance parameter is a presence of gaseous fuel that has exited the cylinder through a second air intake port; and
a controller in communication with the regulator and the at least one sensor, the controller being configured to selectively cause the regulator to adjust the flow of gaseous fuel based on the signal.

Assignees

• Electro Motive Diesel Inc

Inventors

• Fiveland Scott B
• Bandyopadhyay Deep
• Cryer Edward J

Classifications

• Y02T10/30

  Use of alternative fuels, e.g. biofuels · CPC title

• F02D2400/04

  Two-stroke combustion engines with electronic control · CPC title

• F02D19/0607

  to adjust the fuel mass or volume flow · CPC title

• F02D19/0626

  Measuring or estimating parameters related to the fuel supply system · CPC title

• F02D35/027

  using knock sensors · CPC title