Natural gas engine system with improved transient response

Patent metadata

Field	Value
Publication number	US-9856803-B2
Application number	US-201514851129-A
Country	US
Kind code	B2
Filing date	Sep 11, 2015
Priority date	Sep 11, 2015
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A natural gas engine system may have an engine having at least one cylinder. The engine may also have an intake manifold configured to deliver air for combustion to the cylinder and an exhaust manifold configured to discharge exhaust from the cylinder. The natural gas engine system may have a generator coupled to the engine. The generator may be configured to generate electrical power for an electrical load. The natural gas engine system may have a fuel source configured to supply natural gas for combustion in the engine, and an air tank in fluid communication with the intake manifold and the exhaust manifold. Further, the natural gas engine system may have a controller. The controller may be configured to direct a first amount of air from the air tank to the exhaust manifold and a second amount of air from the air tank to the intake manifold.

First claim

What is claimed is:

1. A natural gas engine, comprising:
a plurality of cylinders;
an intake manifold configured to deliver air for combustion to the cylinders;
an exhaust manifold configured to discharge exhaust from the cylinders;
a fuel source configured to supply natural gas for combustion in the cylinders;
an air tank in fluid communication with the intake manifold and the exhaust manifold;
a first control valve disposed between the air tank and the intake manifold;
a second control valve disposed between the air tank and the exhaust manifold;
a first pressure regulator disposed between the air tank and the first control valve;
a second pressure regulator disposed between the air tank and the second control valve;
a controller configured to:
direct a first amount of air from the air tank to the exhaust manifold based on a first electrical load;
direct a second amount of air from the air tank to the intake manifold based on a second electrical load;
adjust the first control valve to direct the first amount of air;
adjust the second control valve to direct the second amount of air;
control the first pressure regulator to regulate a pressure of the first amount of air; and
control the second pressure regulator to regulate a pressure of the second amount of air; and

a turbocharger, including:
a turbine stage configured to be driven by at least one of the exhaust and the first amount of air; and
a compressor stage coupled to the turbine stage, the compressor stage configured to direct a third amount of air from an ambient to the intake manifold.

Assignees

• Caterpillar Inc

Inventors

• Howard Jeff
• James Timothy B
• Rezac Todd A
• Zook Brett A
• Lin David J
• Boyer Gary
• MAXSON Robert

Classifications

• F02B63/04

  for electric generators · CPC title

• F02D41/10

  for acceleration · CPC title

• F02B37/10

  at least one pump being alternatively {or simultaneously} driven by exhaust and other drive, {e.g. by pressurised fluid from a reservoir or an engine-driven pump} · CPC title

• Y02T10/144

  Cross-Sectional Technologies · mapped topic

• F02D41/0027 Primary

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