Patent ID: 8718900
Filing Date: 2014-05-06
Classification: F02D

Abstract:
1. A method to operate an internal combustion engine, comprising: a step of determining a point in time at which ignition or injection of fuel takes place as a start point, and a step of measurement in a cylinder of the point in time which marks the beginning of the combustion phase in the cylinder as a combustion point and a step of measuring a time needed for one cycle of the engine as an engine speed, wherein at least one sensor is or are used to measure combustion intensity as an optical parameter in order to determine the combustion point, with the combustion point being defined as the point where a sharp rise in combustion activity is detected; wherein the at least one sensor is connected with the engine, the start point, the combustion point and the engine speed are determined during operation of the internal combustion engine, and the point in time T_start at which a next ignition or fuel injection is to commence is calculated during operation of the internal combustion engine after start up based on the engine speed T_cycle and on a time delay T_ign between the start point and the combustion point and based on a time deviation T_err between the combustion point and a pre-defined reference point by applying at least one of the equations T_start=T_cycle−(T_ign+T_err) and T_start=T_cycle−(T_ign+T_err/2), without using stored values from a test engine for determining the time delay between the start point and the combustion point.