Gas pressure high and low detection

Patent metadata

Field	Value
Publication number	US-9657653-B2
Application number	US-201414299185-A
Country	US
Kind code	B2
Filing date	Jun 9, 2014
Priority date	Jun 9, 2014
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A system and method for detecting pressure deviation of a first fluid in an engine is disclosed. The method may comprise calculating, for each of a plurality of measurements, a delta between an actual first fluid pressure and a target pressure, summing each delta obtained from the calculating, and determining pressure deviation of the first fluid based on a cumulative sum of the deltas. In an embodiment, the first fluid may be natural gas.

First claim

What is claimed is:

1. A method of detecting pressure deviation of a first fluid in an engine, the method comprising steps of:
calculating, for each of a plurality of measurements, a delta between an actual first fluid pressure and a target pressure;
summing each delta obtained from the calculating step until a summing limit is reached;
determining pressure deviation of the first fluid based on a cumulative sum of the deltas;
triggering a high pressure event flag when the summing limit is reached in a high pressure fail counter; and
providing an operator warning message on a display when the high pressure event flag is triggered.

2. The method of claim 1 , wherein the target pressure is based on a pressure of a second fluid used by the engine, the second fluid different than the first fluid.

3. The method of claim 2 , wherein the first fluid is natural gas and the second fluid is diesel fuel.

4. The method of claim 3 , wherein the actual first fluid pressure is representative of an actual natural gas rail pressure in a gas rail fluidly connected to the engine, and the target pressure is based on a diesel fuel pressure in a diesel rail fluidly connected to the engine.

5. The method of claim 1 , wherein the actual first fluid pressure is representative of an actual natural gas rail pressure in a gas rail fluidly connected to the engine, and the target pressure is based on a natural gas system pressure measured upstream of the gas rail.

6. The method of claim 5 , wherein the natural gas system pressure is measured adjacent to an accumulator disposed upstream of the gas rail.

7. The method of claim 1 , wherein the target pressure is a range.

8. The method of claim 1 , wherein the target pressure is a range including an upper threshold, a desired pressure, and a lower threshold.

9. A method of detecting pressure deviation of a first fluid in an engine, the method comprising steps of:
calculating, for each of a plurality of measurements, a delta between an actual first fluid pressure and a target pressure;
summing each delta obtained from the calculating step until a summing limit is reached;
determining pressure deviation of the first fluid based on a cumulative sum of the deltas;
triggering a low pressure event flag when the summing limit is reached in a low pressure fail counter; and
providing an operator warning message a display when the low pressure event flag is triggered.

10. The method of claim 9 , wherein the engine is only supplied with diesel fuel when the low pressure event flag is triggered.

11. A method of operating a dual fuel engine, the method comprising steps of:
sensing a gaseous fuel pressure by a plurality of measurements;
calculating, for each of the plurality of gaseous fuel pressure measurements, a delta between an actual gaseous fuel pressure and a target gaseous fuel pressure;
summing each delta obtained from the calculating step until a summing limit is reached;
determining a pressure deviation of the gaseous fuel based on a cumulative sum of the deltas; and
initiating an operational engine response if the pressure deviation of the gaseous fuel exceeds a threshold.

12. The method of claim 11 , wherein the target gaseous fuel pressure is based on a pressure of a liquid fuel used by the engine.

13. The method of claim 12 , wherein the gaseous fuel is natural gas and the liquid fuel is diesel.

14. The method of claim 12 , wherein the actual gaseous fuel pressure is representative of a pressure in a gaseous fuel rail fluidly connected to the engine, and the target gaseous fuel pressure is based on a liquid fuel pressure in a liquid fuel rail fluidly connected to the engine.

15. The method of claim 11 , wherein the actual gaseous fuel pressure is representative of a pressure in a gaseous fuel rail fluidly connected to the engine, and the target gaseous fuel pressure is based on a natural gas system pressure upstream of the gaseous fuel rail.

16. The method of claim 15 , wherein the natural gas system pressure is measured adjacent to an accumulator disposed upstream of the gaseous fuel rail.

17. The method of claim 11 , wherein the target gaseous fuel pressure is a range including an upper threshold, a desired pressure, and a lower threshold.

18. The method of claim 11 , wherein the step of initiating an operational engine response if the pressure deviation of the gaseous fuel exceeds a threshold includes triggering a high pressure event flag in an engine controller when the summing limit is reached in a high pressure fail counter and displaying an operator warning.

19. The method of claim 11 , wherein the step of initiating an operational engine response if the pressure deviation of the gaseous fuel exceeds a threshold includes triggering a low pressure event flag in an engine controller when the summing limit is reached in a low pressure fail counter and displaying an operator warning.

20. The method of claim 19 , wherein the engine is supplied with only diesel fuel when the low pressure event flag is triggered.

Assignees

• Caterpillar Inc
• Caterpillar Inc

Inventors

• Ensan Behnaz
• Grant Steven Thomas
• Yandell Matthew Benjamin
• Shah Hardikkumar
• Bean Sunil Jefferey

Classifications

• F02D2041/224

  Diagnosis of the fuel system · CPC title

• F02D41/0027

  the fuel being gaseous (non-electrical control F02D19/02) · CPC title

• F02D19/105

  operating in a special mode, e.g. in a liquid fuel only mode for starting · CPC title

• G01L13/00

  Devices or apparatus for measuring differences of two or more fluid pressure values · CPC title

• F02D19/0647

  the gaseous fuel being liquefied petroleum gas [LPG], liquefied natural gas [LNG], compressed natural gas [CNG] or dimethyl ether [DME] · CPC title