A Novel Methodology of AC Signal Detection Using Wavelet

Abstract

Abstract. In this paper, we propose a novel AC signal detection approach to DC power system. Combining with state-of-the-art detection circuit and WNN(wavelet based neural network). Aiming at handling with the travelling wave and fault signal cannot be detected accurately with the uncertainty of signal velocity when AC signal injected. In which, the injected AC signal in DC power system is detected via the current transformers and the voltage transformers distributed in different current loops. The acquire signal acts as the original fault signal and the sub-band energy function of wavelet packet decomposition is used as secondary characteristic and the minimum distance is used as the criterion in WNN method. Experimental analysis is conducted to show the effectiveness an robustness of our approach. The final conclusion shows that detecting AC signals in DC power system is possible with our propose method.