Method, apparatus, and system for controlling natural gas engine operation based on fuel properties
AssigneeCummins Inc.
InventorsCarlos Alcides Lana, Yilun Liu, Philipe F. Saad, Ganesh Raghunath
Life of this patent
Estimating the term…
Abstract
A method, system, and apparatus use infrared spectrometry onboard an internal combustion engine running on a natural gas fuel to detect characteristics of the fuel. At a site having a plurality of natural gas engines, detection of natural gas fuel components and concentrations of the components also is conducted at the site upstream of the point of intake of the natural gas fuel to one or more of the engines. Operating parameters of the engine or a plurality of the engines may be controlled on the basis of the detected composition of the natural gas fuel.
Claims18
A method of operating an engine system, comprising:
- determining a first characteristic of a natural gas fuel supplied to a plurality of engines of the engine system using a first analyzer disposed upstream of a fuel inlet of each of the plurality of engines, wherein the first characteristic includes identification of a plurality of components of the natural gas fuel;
- determining a second characteristic of the natural gas fuel using a second analyzer disposed onboard of one of the plurality of engines downstream of the fuel inlet to the one of the plurality of engines, wherein the second characteristic includes a concentration of one or more of the identified components of the natural gas fuel determined by the first analyzer;
- determining a fuel flow value for the natural gas engine in response to an air-fuel ratio target and a mass air flow to the natural gas engine;
- estimating an air-fuel ratio based on the identification of the plurality of components of the natural gas fuel from the first analyzer and the concentration of the one or more of the identified components of the natural gas fuel from the second analyzer;
- determining a fuel flow correction value based on the fuel flow value and the estimate of the air-fuel ratio;
- and
- providing a total fuel flow command based on the fuel flow value and the fuel flow correction value.
A control system for a natural gas engine, comprising:
- a processor coupled to an input and an output, wherein the input is adapted to receive a first characteristic of a natural gas fuel supplied to a plurality of natural gas engines, detected by a first analyzer disposed upstream of a fuel inlet of each of the plurality of natural gas engines wherein the first characteristic includes identification of a plurality of components of the natural gas fuel, and a second characteristic of the fuel detected by a second analyzer disposed downstream of the fuel inlet to the natural gas engine wherein the second characteristic includes a concentration of one or more of the identified components of the natural gas fuel determined by the first analyzer, the output is adapted to provide a control command to the natural gas engine, wherein the processor is configured to:
- determine a fuel flow value for the natural gas engine in response to an air-fuel ratio target and a mass air flow to the natural gas engine;
- estimate an air-fuel ratio based on the identification of the plurality of components of the natural gas fuel from the first analyzer and the concentration of the at least one of the plurality of components of the natural gas fuel from the mid-infrared analyzer;
- determine a fuel flow correction value based on the fuel flow value and the estimate of the air-fuel ratio;
- and
- provide the control command to the output as a total fuel flow command based on the fuel flow value and the fuel flow correction value.
An engine system, comprising:
- a plurality of natural gas engines;
- a first analyzer disposed upstream of a fuel inlet to each of the plurality of natural gas engines, the first analyzer being configured to identify a plurality of components of the natural gas fuel;
- a mid-infrared analyzer disposed onboard one of the plurality of natural gas engines;
- and
- a controller coupled to the one of the plurality of natural gas engines, the controller being configured to determine a concentration of at least one of the plurality of identified components of the natural gas fuel supplied to the one of the plurality of natural gas engines based on detection of the concentration of one or more of the plurality of identified components of the natural gas fuel by the mid-infrared analyzer, and wherein the controller is configured to:
- determine a fuel flow value for the one of the plurality of natural gas engines in response to an air-fuel ratio target and a mass air flow to the one of the plurality of natural gas engines;
- estimate an air-fuel ratio based on the identification of the plurality of components of the natural gas fuel from the first analyzer and the concentration of the at least one of the plurality of components of the natural gas fuel from the mid-infrared analyzer;
- determine a fuel flow correction value based on the fuel flow value and the estimate of the air-fuel ratio;
- and
- provide a control command to the one of the plurality of natural gas engines as a total fuel flow command based on the fuel flow value and the fuel flow correction value.
Dependencies are inferred from the claim text.