Harmonic analysis via wavelet packet decomposition using special elliptic half-band filters

The Fast Fourier Transform is the most widely used power system harmonic analysis tool in real little power metering due to its computational efficiency. Recently, an alternate method, wavelet packet decomposition, has been applied to power system signals to meter voltage and current harmonics. Although the new method provides better analysis, the computational complexity of wavelet packet decomposition places a limitation on its use in real time metering. This paper proposes the use of all-pass implemented half-hand elliptic IIR filters in the wavelet packet decomposition of power system signals. The proposed implementation reduces the computational complexity to levels comparable to Fast Fourier Transform.