Method for reducing signal distortion in an electro-mechanical transducer based on magnetic flux modes

Method for attenuating the linear and nonlinear signal distortions in an output signal of a passive electro-mechanical transducer using a movable, mechanical drive element, wherein a time-varying electric current iC in a coil alters the magnetic field distribution in the transducer, generates a mechanical force Fx and a displacement x of the mechanical drive element, and a temporal change in the current iC or displacement x causes an electrical induction voltage uI in the coil;

• characterized by the steps:
• I. Modelling of the magnetic flux distribution in the transducer as a sum of modal fluxes Φm, where static nonlinearities without memory are separated from linear dynamical systems with memory in each modal flux;
• II. Determination of a number MT of modal fluxes and identification of free parameters introduced by modeling based on measured electrical or mechanical signals at the transducer;
• III. Determination of at least one modal flux Φm by means of a modal magnetomotive force Fm and a modal reluctance Rm;
• wherein at least one magnetomotive force Fm is described by means of a first modal nonlinearity NF,m(x), which is a memoryless function of the displacement x;
• and the modal reluctance Rm captures the magnetic properties of the material through which the modal flux Φm flows, and the electrical conductivity of the material causes a memory and thus a frequency dependence of the modal reluctance;
• IV. Determination of at least one linked modal flux λm with m=1, . . . , MT by multiplying the modal flux Φm by a second modal nonlinearity Nλ,m(x);
• V. Determination of the induction voltage uI by temporal differentiation of the sum of all linked modal fluxes λm with m=1, . . . , MT;
• VI. Determination of the mechanical force Fx using the modal fluxes Φm with m=1, . . . , MT;
• VII. Determination of the displacement x by means of the mechanical force Fx;
• and
• VIII. Reduction of signal distortions based on modelling and identified parameters by structurally changing the geometric and material properties of the passive transducer or by actively compensating for signal distortions with the help of electrical control.