Impedance estimation through the Taylor-Kalman-Fourier filter applied to distance relays

This paper proposes the application of a second order Taylor-Kalman-Fourier filter (T
²
KF) to distance relays. Due to filtering requirements in distance relays are quite critical, it is relevant that a digital filter estimates precisely and quickly the impedance from current and voltage phasor estimates; such calculation must be reliable. In this paper, the proposed filter improves the steady-state and transient responses. Comparisons are made respect to the fast Fourier transform (FFT) and a cosine filter on one-cycle rectangular windows. Simulations are carried out in order to assess the proposal.