Method when driving a vehicle and a computer program for this, a system for implementing the method and a vehicle comprising the system

摘要

A method operable when driving a vehicle, wherein the vehicle has an internal combustion engine with at least one combustion chamber as well as an air supply to said combustion chamber that can be controlled, wherein, when driving said vehicle, an air/fuel ratio in said combustion chamber is controlled such that said air/fuel ratio does not fall below a first limit value (λb), and wherein said air/fuel ratio is also controlled such that a first margin (Δλm0) with respect to said first limit value (λb) is maintained. The method includes determining a first measure (M) of a requirement for a margin with respect to said first limit value (λb), and if said first measure (M) of said requirement represents a reduced requirement for a margin with respect to said first limit value, reducing said first margin (Δλm0) with respect to said first limit value (λb) to a second margin being smaller than said first margin.

主权项

1. A method for controlling an air/fuel ratio when driving a vehicle, wherein said vehicle comprises an internal combustion engine with at least one combustion chamber a controllable air supply to said combustion chamber, the method comprising the steps of:
controlling said air/fuel ratio in said combustion chamber such that said air/fuel ratio does not fall below a first limit value (λb); controlling said air/fuel ratio such that a first margin (Δλm0) with respect to said first limit value (λb) of said ratio is maintained; determining a first measure of a requirement for a margin with respect to said first limit value (λb); and reducing said first margin (Δλm0) with respect to said first limit value (λb) to a second margin (Δλm1) smaller than said first margin if said first measure of said requirement for said margin represents a reduced requirement for the margin with respect to said first limit value.