Application of wavelet transform in ferroresonance detection

With the development of power systems and the extensive application of nonlinear elements in the electricity system, the problem of ferroresonance do harm to the network and electricity facilities has become more prominent. Wavelet analysis has good time-frequency localization characteristic, so it is suitable for fault analysis of power system. This paper is base on in the neutral point unearthed system, which is excited by single phase grounding fault, take analysis of the value of neutral point with the Daubechies wavelet analysis. Simulation results show that with wavelet transforms the occurrence of Ferro resonance time can be detected and the frequency resonance can also be determined.