METHOD FOR ONLINE EVALUATION OF FAILURE CAUSED BY ROTORIC ECCENTRICITY GENERATORS AND SYNCHRONOUS MOTORS

摘要

The invention concerns a on-line evaluation of failure due to rotoric eccentricity in generators/synchronous motors by measuring inner currents of statoric winding and spectral analyses of analytical signals derived from the same by complex transformation, said method comprising the steps of: a1. Eventually a commissioning a1. step to determine parameters (a, b, c, prif), necessary in an eventual folloqing step f.; a. measurement of instantaneous inner statoric currents b. calculation of complex vectors i^(q)) by formula wherein α = e^j(2π/n); c. spectral analyses of analytical signal associated with complex vectors of p±1 order: i(p-1), i(p+1); d. extraction of amplitudes of spectral components S1, D1, S2, D2, wherein: S7=amplitude of component with frequence f of current i(p-1); D1= amplitude of component with frequence (f-f/p) of current KM) S2= amplitude of component with frequence f of current i(p+1) D2= amplitude of component with frequence (f+f/p) of current i(p+1) p=number of polar couples of synchronous machine e. calculation of instantaneous eccentricity applying formulae and f. eventually, and only if preliminary commissioning step was carried out, to increase precision under load, it is possible, also measuring tension, estimating field angle (zeta, ζ) and thus corrective coefficient Κ(ζ).