A wavelet based novel method for identification of harmonics in a signal

Presence of harmonics in power system is a major concern in power system due to extensive use of power electronic devices. It is a necessary requirement that the specific harmonics be identified so that corrective measures can be taken. This paper presents a new method for identifying the presence of specific harmonic levels in voltage signal based on discrete wavelet transform. The detail voltage at the first level of decomposition is considered for analysis. Identification of harmonics is done by using different sampling frequencies so that contribution of each harmonics can be clearly estimated. The simulation results presented here show that the proposed method can effectively indicate the presence of specific harmonics levels in a signal.