Spectral Analysis Algorithm for the Diagnosis of Electrical Machines

The paper addresses general issues related to signal analysis with Fourier transform in the context of electrotechnical tasks. A detailed description of relation among continuous Fourier transform, discrete-time Fourier transform (DTFT), and discrete Fourier transform (DFT) is provided. DFT frequency resolution increase methods are compared. Analysis algorithm of DFT results is provided. The algorithm allows increasing the accuracy of identifying harmonic composition of a signal and also revealing closely spaced harmonics that substantially differ in amplitudes.