Harmonic Detection Via Wavelet Packet Decomposition Using Special Elliptic Half-Band Filters

Power system harmonic measurement was studied in this paper. Elliptic IIR filter was choosed because it require a few number of multiplications and have better low-pass characteristic. The computational complexity of various FIR and IIR filter banks as well as their frequency roll-off characteristics are compared. Design method about elliptic IIR filter is presented. The Simulation result shows that the use of all-pass implemented half-band elliptic IIR filters in the wavelet pocket decomposition of power system harmonics signals reduces the computational complexity to levels comparable to fast Fourier transform.