Process and system for automatically controlling the fraction of the exhaust gas quantity returned to an internal-combustion engine

US6378508B1 · kind B1 · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Tillmann Braun · Winnenden, DE
• Uwe Gartner · Winnenden, DE

Key dates

• Filing date: Mar 17, 2000
• Grant date: Apr 30, 2002
• Expiry date: Mar 17, 2020

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/40
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A process and system are provided for automatically controlling the fraction of the exhaust gas quantity returned to an internal-combustion engine with respect to the mixture quantity fed on the whole to the internal-combustion engine. The mixture quantity is formed by the returned exhaust gas quantity and a fresh air quantity. The actual fraction with respect to the mixture quantity fed on the whole is determined by sensors measuring a plurality of operating parameters selected from the temperature of the fed fresh air quantity, the temperature of the returned exhaust gas quantity, the temperature of the mixture quantity fed as a whole, the temperature of the exhaust gas flowing out of the internal-combustion engine, the flow rate of the fresh air quantity fed to the internal-combustion engine, and the flow rate of the mixture quantity fed on the whole to the internal-combustion engine. This actual fraction of the returned exhaust gas quantity is adapted to a predetermined desired fraction. The returned exhaust gas quantity is automatically controlled to a predetermined content of nitrogen oxides in the exhaust gas.