Internal combustion engine`s combustion chamber interior pressure signal correcting method, involves determining distribution of absolute cylinder pressure, and polytrophic exponent and offset pressure using kalman-filter

摘要

The method involves detecting measured cylinder pressure (pm) in a compression phase of an internal combustion engine (2) using a combustion chamber pressure sensor (1), and determining distribution of absolute cylinder pressure (pzyl) from the detected cylinder pressure based on polytrophic equation. A polytrophic exponent (n) of the equation and an offset pressure (poffset) are determined using an adjusted kalman-filter (3) with a markow-process of two orders, where the determined exponent is changed from one cycle to other cycle.