Fast harmonic computation for digital relaying

It has becn receiibly shown that thc fast Fourier t,ransform of a scqucncc which slides over a time-limited rectangular window can bc carricd out in a nori-recursivr manner by means of O(N) comput,ations. The same idea is applied in this paper to the digital relaying field, where only ccrt,airi isolat,cd harmonics, rather than t,he full spectrum, are needed, leading to O(log, N) <:ompul.ations per harmonic. Tho particular case N = 16 has bcen used for comparison purposes, showing that t,he new techniquc is less expensive than other non-recursivc algorithms appeared in t,ho litcrat,urc.