US 6,308,517 B1 · Automatic charging pressure control and automatic exhaust gas recirculation control system in an internal-combustion engine, particularly a diesel engine

Abstract

A system for automatic charging pressure control using an exhaust gas turbocharger with a variably adjustable turbine cross-section and for automatic exhaust gas recirculation control in the case of an internal-combustion engine, particularly a diesel engine. An automatic control system has a first controller which has an output for the variation of the turbine cross-section of the exhaust gas turbocharger. The command variable for the automatic exhaust gas recirculation control in a first low load-rotational speed range is the air flow rate in the intake pipe. The command variable for the automatic charging pressure control in a second higher load-rotational speed range is the charging pressure in the intake pipe. For the automatic exhaust gas recirculation control, an exhaust gas recirculation pipe connects the exhaust gas pipe with the suction pipe. In the case of this system, for achieving the lowest possible pollutant emission while simultaneously minimizing fuel consumption, exhaust gas recirculation rates which are as precise as possible are defined in the lower load-rotational speed range, and a charging pressure which is as precise as possible is defined in the upper load-rotational speed range via a corresponding automatic control.

Claims22

Dependent claims

A system for automatic charging pressure control and automatic exhaust gas recirculation control in an internal-combustion engine, said system comprising:

an exhaust gas turbocharger with a turbine having a variable adjustable cross-section and a compressor, said compressor being connected in line with a suction pipe and said turbine being connecting in line with an exhaust gas pipe;
an air flow sensor connected upstream of said compressor in the suction pipe;
a pressure sensor connected in line with said suction pipe for measuring charging pressure and an exhaust gas recirculation pipe connecting said exhaust gas pipe with said suction pipe;
and
an automatic control device which controls exhaust gas recirculation during a first low load-rotational speed range of said internal combustion engine and which automatically controls a charging pressure in the suction pipe during a second higher load-rotational speed range of the internal combustion engine, said automatic control device including a first controller providing a first output for varying the cross-section of the turbine in response to a command variable for adjustment of an exhaust gas recirculation delivery gradient to provide exclusive control of said exhaust gas recirculation control from said air flow sensor in the suction pipe during operation of said engine in said first low load-rotational speed range and wherein said first controller provides a second output for the variation of the cross-section of the turbine in response to a command variable from said pressure sensor for automatic charging pressure control during the second higher load-rotational speed range of said engine.

2 more elements

An automatic charging pressure control and automatic exhaust gas recirculation control system for an internal-combustion engine, comprising:

an exhaust gas turbocharger having a compressor and a turbine, said turbine having a variably adjustable cross-section;
an engine suction pipe, said compressor of the turbocharger being arranged in the section pipe;
an air flow sensor arranged upstream of the compressor in the suction pipe;
a pressure sensor connected in line with said suction pipe for measuring charging pressure;
an engine exhaust gas pipe in which the variably adjustable turbine is arranged;
an exhaust gas recirculation pipe connecting the exhaust gas pipe with the suction pipe;
an automatic control device which, in a first low load rotational speed range, automatically controls the exhaust gas recirculation and, in a second higher load rotational speed range, automatically controls the charging pressure in the suction pipe by a corresponding variation of the variably adjustable turbine cross-section;
wherein the automatic control device comprises a first controller having a controller output for controlling the variably adjustable turbine cross-section such that, in the first low load rotational speed range, an air flow rate value from the air flow sensor functions as a command variable for adjustment of an exhaust gas recirculation delivery gradient to provide exclusive automatic exhaust gas recirculation control during said low load rotation speed range and, in the second higher load rotational speed range, a charging pressure in the suction pipe functions as the command variable for the automatic charging pressure control.

5 more elements

Dependencies are inferred from the claim text.

Automatic charging pressure control and automatic exhaust gas recirculation control system in an internal-combustion engine, particularly a diesel engine

Life of this patent

Automatic charging pressure control and automatic exhaust gas recirculation control system in an internal-combustion engine, particularly a diesel engine

Life of this patent

Abstract

Claims22