Process for cleaning exhaust gas using lambda control

US6550307B1 · kind B1 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Hong Zhang · Tegernheim, DE
• Gerd Roesel · Regensburg, DE

Key dates

• Filing date: Dec 6, 1999
• Grant date: Apr 22, 2003
• Expiry date: Dec 6, 2019

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D41/2474
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A process for cleaning exhaust gas flow from an internal combustion engine using a catalyst, a lambda probe is disposed in the exhaust gas flow upstream from the catalyst and is connected to a controller that actuates the lambda probe, the controller receives a raw signal output from the lambda probe and forms a measurement signal that is supplied to control the internal combustion engine. The process includes regulating operation of the internal combustion engine such that a predetermined value of the lambda probe corresponds to a certain level of the measurement signal. Trimming the certain level of the measurement signal by a set value determined with an additional measuring pickup located downstream of the catalyst is performed, the trimming corrects the certain level of the measurement signal that corresponds to the predetermined value of the lambda probe. Switching the controller to a test mode in predetermined states of operation by the internal combustion engine and determining an actual value of a measurement signal falsification developed in the controller is performed. Compensating the measurement signal inversely to the actual value of the measurement signal falsificati…