UNITECH 2017, Gabrovo, Bulgaria, 17 - 18 November 2017, vol.1, pp.166-170
This paper presents a robust method to investigate transformer time series transient characteristics under no load conditions. As an extreme condition, no-load (or light load) is an undesired event which is constantly monitored to eliminate power system failure. In this study, a 220V/34.5kV test transformer is employed to record no-load voltage and current waveforms via high-speed oscilloscope. During the tests, the transients are analyzed by focusing on fist 0.08s of current and voltage waveforms, which is quite adequate approach. The recorded time series signals are computed by using Higuchi’s fractal dimension (HFD) analysis, which is an efficient method to define fractal dimension (complexity) for specific time segments. According to HFD analysis the waveforms exhibit extremely (in terms of fractal dimension) distinctive HFD results for the signals in defined time durations.