Patent Number: 6,253,750

Title: Model based purge system

Abstract: A method is provided for accommodating the purge vapors from an evaporative emission control system of an automotive vehicle. The method includes a purge compensation model to identify the concentration of purge vapor entering the intake manifold of the engine of the automotive vehicle, identifying the source of the vapor as from the vapor collection canister or the fuel tank using a characteristic mapping of maximum concentration as a function of instantaneous flow and accumulated flow through a canister and uses this information to predict variations in vapor concentrations as a function of purge flow. The method also includes a purge control model which uses mode logic to identify an appropriate time to initiate a purge cycle, provides the flow conditions necessary for a learning portion of the purge compensation model and increases purge flow rates after the learning is complete to deplete the contents of the canister. The purge control model also manages the time spent with purge active (learning purge) and purge inactive (learning volumetric efficiency or EGR).

Inventors: Duty; Mark J. (Davison, MI), Coatesworth; Timothy A. (Lake Orion, MI)

Assignee: DaimlerChrysler Corporation

International Classification: F02D 41/00 (20060101); F02D 41/14 (20060101); F02M 25/08 (20060101); F02M 025/08 (); F02D 041/14 ()

Expiration Date: 07/03/2018