Research and simulation of comprehensive reference current extraction strategy based on Goertzel-IIR filter

The reference current detection algorithm is a key technology for active filter and reactive power compensation devices, as its extraction accuracy directly affects output current of this kind of equipment. Traditional harmonic detection algorithm based on instantaneous reactive power has the problems of complex coordinate transformation, slow response speed of low-pass filter and low extraction precision. To address these issues, the Goertzel-IIR filter is adopted and implanted into the SDFT by mathematical transformation, on the base of which the comprehensive extraction scheme of harmonic, reactive and unbalanced reference currents is proposed. Finally, the correctness of the proposed stability analysis is validated via simulation in MATLAB, the simulation results show that the reference current detection algorithm can extract the comprehensive current quickly and accurately.