| 摘要 |
The invention relates to a method and device for the differentiation of partial discharges and noise, calculating a power ratio for low frequencies (PRL) and a power ratio for high frequencies (PRH): formula (I), in which: s(f) is the FFT of the pulse signal s(t); fT is a selected maximum frequency; and f1L, f2L, f1H, f2H, fT are frequencies that define a low frequency band [f1L, f2L] and a high frequency band [f1H, f2H] configured to calculate the power ratio for low and high frequencies (PRL, PRH) respectively, said frequencies meeting the following conditions: 0<f1L<f2L; f1H<f2H≤fTy f1L<f2H. The method differentiates the detected pulse signal s(t) into noise and a partial discharge, defining a location on a 2-D map of the point defined by the coordinates (PRL, PRH) associated with the pulse signal s(t). The invention comprises a flexible noise identification tool that can be used to characterise pulses since the frequency bands can be changed online. |
