Determining the opening behavior of a fuel injector by means of an electrical test excitation without a magnetic saturation

摘要

A method is described for determining an opening behavior of a coil drive having a fuel injector for an internal combustion engine of a motor vehicle. The method comprises (a) subjecting a coil of the coil drive with an electrical test excitation (211, 221), which compared to a standard electrical excitation (210, 220), which is applied to the coil during normal operation of the internal combustion engine, is weaker, so that reaching an opening position of the fuel injector at a time when the coil drive is not in a magnetic saturation, (b) measuring the time course of an electrical variable (I) of the coil, (c) determining a first Time (t2 ') at which the fuel injector under the influence of the electrical test excitation reaches its opening position, based on the measured time course of the electrical variable (I), and (d) determining a second time (t2), to which Fuel injector under the influence of standard electrical excitation (210, 220) would reach its open position, based on the determined e first time (t2 '). A device (100) and a computer program for carrying out this method are also described. In addition, a method for determining a correlation between a test opening behavior and a standard opening behavior of a fuel injector and a method for driving a fuel injector will be described.