Method for dynamic diagnosis of an exhaust gas analyzer probe

US7269996B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Eberhard Schnaibel · Hemmingen, DE
• Kersten Wehmeier · Ludwigsburg, DE

Key dates

• Filing date: Jul 12, 2006
• Grant date: Sep 18, 2007
• Expiry date: Jul 12, 2026

Classification

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

Abstract

A method for the dynamic diagnosis of an exhaust gas analyzer probe situated in an exhaust-gas system having at least one exhaust-gas catalytic converter, of an internal combustion engine, a measuring signal (lambda-actual) of the exhaust gas analyzer probe being compared to a setpoint value (lambda-setpoint) as a function of the operating state of the internal combustion engine, and the system deviation being supplied to a controller, which regulates the operating parameters of the internal combustion engine correspondingly, the dynamic diagnosis of the exhaust gas analyzer probe being implemented with a closed control loop, and the deviation from the setpoint value (lambda-setpoint) of the measuring signal (lambda-actual) of a slowing exhaust gas analyzer probe being amplified by the intervention of the controller and the dynamic diagnosis is implemented on the basis of this amplified deviation. The method allows a reliable diagnosis of the dynamic response of the exhaust gas analyzer probe with excellent differentiation with respect to stochastically occurring fault signals.