A kind of the fractal analyzing method of nanosecond-order discharge signal

In recent years, great progresses have been made in technique for partial discharge detection, such as high frequency technique and ultra-wideband technique. Using these kinds of detective technique, we can get abundant information of partial discharge with high frequency. But it is rather difficult to analyze characteristics of nanosecond-order discharge signals in different frequency-band and to express those in quantities. In this paper, a kind of new method is introduced into analysis of the nanosecond-order discharge signals. First, an nanosecond-order discharge signal is analyzed into different frequency components based on wavelet analysis, then the fractal dimensions of the signal in each frequency-band is calculated, and the characteristics of the partial discharge signals can be expressed in quantities with fractal dimensions. By this method, the fractal characteristics of nanosecond-order discharge signals in different frequency-band can be analyzed clearly. And then, by using the analyzing method, the discharge characteristics of epoxy sample with different kinds of electrode system are analyzed, and the feature peaks of nanosecond-order discharge for these samples can be founded clearly. It is the base for the further study of the nanosecond-order discharge.