Method for evaluating an ion current signal of a self-igniting internal combustion engine

US6279538A · kind A · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Ruediger Herweg · Eßlingen, DE
• Katsuyoshi Koyanagi · Eßlingen, DE
• Rudolf Maly · Sindelfingen, DE
• Gerhard Muenkel · Fellbach, DE
• Gregor Renner · Stuttgart, DE
• Hartung Wilstermann · Gaildorf, DE

Key dates

• Filing date: Aug 23, 1999
• Grant date: Aug 28, 2001
• Expiry date: Aug 23, 2019

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 evaluating an ion current signal of a self-igniting internal combustion engine, with the ignition shift being derived from the time shift of the local maximum in the curve of the ion current signal relative to an injection point in time. Similarly, continuous injection in a cylinder can be detected when the ion current signal is integrated and evaluated in terms of area and/or when the position and/or height of the maximum of the ion current signal are evaluated. Carbon formation can be detected by an evaluation of the time curve of the ion current signal following an injection. For example, the parameters of the main injection can be controlled as a function of an evaluation of the measured ion current following a preinjection. When a continuous injection is detected, injection can be suppressed at least in those cylinders in which continuous injection was detected.