METHOD ESTABLISHING NONLINEARITY FACTOR OF CHARACTERISTIC OF PARABOLIC TYPE OF NONLINEAR INERTIA-FREE ELEMENT Russian patent published in 2003 - IPC

FIELD: devices with programmed nonlinearity, nonlinearity discriminators or testing instruments. SUBSTANCE: proposed method is insensitive to change of amplitude of harmonic signal and, as result, to simultaneous drift of amplitudes of harmonic components across output of nonlinear inertia-free element, it does not require a priori knowledge of operating angle. Method establishing nonlinearity factor of characteristic of parabolic type of nonlinear inertia-free element includes uninterrupted supply of harmonic oscillation to nonlinear inertia-free element, spectral analysis of signal across output of nonlinear inertia- free element by which results value of nonlinearity factor of parabolic characteristic is obtained, usage of nonlinear inertia- free element with operating angle, conversion of signal across output of nonlinear inertia-free element to digital form, digital spectral analysis of output signal, sampling from any five adjacent harmonic components from spectrum of output signal with established values of amplitudes and phases of these harmonic components, finding of serial number of second harmonic out five chosen harmonics in common series. Nonlinearity factor of parabolic characteristic is computed by values of amplitudes and phases from five chosen adjacent harmonic components. EFFECT: raised reliability of method. 3 cl, 2 dwg