Edinburgh Napier University

  This paper introduces a new way to extract the
fault components of a signal by means of a new proposed filter
based on the Sampling Theorem and the properties of Discrete
Fourier Transform. The proposed method is able to extract
fault components either in steady-state or in transient
conditions. This paper also proposes a new way to compute the
energy of a signal in the frequency domain by means of the
Plancherel's Theorem. Unlike the Discrete Wavelet Transform,
which makes the filtering process in the time domain, the
Discrete Fourier Transform allows the filtering process in the
frequency domain. The use of the Discrete Fourier Transform
makes the filtering process possible without applying any pretreatment
to the current as it is done in the former works. As a
consequence of the filtering process in the frequency domain
and in order to reduce useless computations, in the current
paper is also demonstrated the possibility of the computation of
the energy of the extracted fault component in the frequency
domain. The results are compared with the former and already
published works in the area showing the good reliability of the
new filtering process and energy computation in the frequency
domain.