Harmonics and interharmonics estimation using wavelet transform

This paper presents the harmonics and interharmonics estimation of nonstationary signals. The approach is based on wavelet transform analysis. Wavelet transform decomposes the non-stationary signal into sub-band frequency. The decomposition is performed using discrete wavelet transform. Discrete wavelet transform is implemented by using Quadrature Mirror Filter (QMF) Bank. The non-stationary signal are passed through the finite impulse response (FIR) QMF filtering. The coefficient of wavelet on the time-frequency plane. The continuous wavelet transform is applied to the decomposed sub-bands to estimate the harmonics and interharmonics frequencies and amplitude. The harmonics and interharmonics estimation has been tested on nonstationary signal including transient and capacitor bank switching signal.