Determining the temporal movement behavior of a fuel injector based on an evaluation of the time course of various electrical parameters

摘要

A method for determining the temporal movement behavior of a coil drive fuel injector for an internal combustion engine of a motor vehicle, comprising the method Acting on a coil of the coil drive with an electrical excitation, which leads to an opening movement of a valve needle which is coupled to a magnet armature of the coil drive, Detecting the time course of a first electrical measurement of the coil, Determining the time of the end of the opening movement based on the detected time course of the first electrical measurement, Modifying the electrical excitation of the coil so that the valve needle performs a closing movement, Detecting the time course of a second electrical measurement of the coil and Determining the time of the end of the closing movement based on the detected time course of the second electrical measurement, wherein the first electrical measure is the magnitude of the current flowing through the coil, and wherein the second electrical measurand is the magnitude of the voltage applied to the coil.