Method for heating a catalytic converter and exhaust gas aftertreatment system

US11261771B2 · kind B2 · utility

Assignee

• VOLKSWAGEN AKTIENGESELLSCHAFT · DE

Inventors

• Falk-Christian Baron Von Ceumern-Lindenstjerna · Braunschweig, DE
• Stefan Paukner · Wolfsburg, DE
• Michael Kaack · Bochum, DE

Key dates

• Filing date: Aug 7, 2020
• Grant date: Mar 1, 2022
• Expiry date: Aug 7, 2040

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/40
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

A method for heating a catalytic converter in an exhaust system of an internal combustion engine, in which an exhaust gas burner for heating the catalytic converter is arranged, upstream of the catalytic converter. A lambda probe for controlling the combustion air ratio of the exhaust gas burner is arranged immediately downstream of the exhaust gas burner and upstream of the catalytic converter. The method includes operating the internal combustion engine with a stoichiometric combustion air ratio (λE=1), activating the exhaust gas burner, which is operated alternately with a substoichiometric combustion air ratio (λB<1) and a superstoichiometric combustion air ratio (λB>1), wherein from the substoichiometric combustion air ratio (λB<1) to the superstoichiometric combustion air ratio (λB>1) as soon as a rich breakthrough is detected by the second lambda probe (34), and wherein a switchover from the superstoichiometric combustion air ratio (λB>1) to the substoichiometric combustion air ratio (λB<1) takes place as soon as a lean breakthrough is detected by the second lambda probe.