Method and generator for characterizing an oscillatory system

Abstract

The present invention relates to a method for determining at least one physical characteristic value of an electromechanical oscillatory system, which comprises a piezoelectric element and at least one additional element coupled, with respect to oscillation, to the piezoelectric element, the piezoelectric element having an electrode and a counter electrode. The method comprises the following steps: (a) applying an electrical alternating voltage between the electrode and the counter electrode for the duration of an excitation interval in order to induce mechanical oscillation of the oscillatory system or of a sub-system of the oscillatory system, so that after the excitation interval has expired, the oscillatory system or the sub-system performs a free oscillation without excitation, (b) after the end of the excitation and during the free oscillation of the oscillatory system or of the sub-system without excitation: (i) measuring a time curve of a voltage U between the electrode and the counter electrode, or (ii) short-circuiting the electrode and the counter electrode with a line and measuring a time curve of a current I through the line, and (c) determining the at least one physical characteristic value of the electromechanical oscillatory system from the time curve of the voltage U, which time curve was measured in step b) i), or the time curve of the current I, which time curve was measured in step b) ii).