Process for controlling the charging pressure in an exhaust gas turbocharger with an adjustable turbine geometry

US5850737A · kind A · utility

Assignee

• Mercedes-Benz Group AG · DE

Inventors

• Werner Aschner · Ulm, DE
• Horst Hanauer · Murrhardt, DE
• Gernot Hertweck · Fellbach, DE

Key dates

• Filing date: Aug 30, 1996
• Grant date: Dec 22, 1998
• Expiry date: Aug 30, 2016

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

The invention provides a process for adjustment of the charging pressure in an internal-combustion engine exhaust gas turbocharger having an adjustable turbine geometry, to a predetermined operating-point-dependent desired charging pressure value. A fuzzy control function in an electronic control unit has as input quantities, a control difference and a control quantity, the latter being determined as the difference between an engine-operating-point-dependent maximum permissible differential pressure and a current differential pressure. The differential pressure is calculated as the difference from the exhaust back pressure and the charging pressure, so that unacceptable super elevation of the exhaust back pressure is recognized in the case of a positive load change, and is corrected by opening the blade position of the exhaust gas turbocharger with the variable turbine geometry, so that an optimum buildup of the torque takes place.