An asymptotic and algebraic estimation method of harmonics

Abstract

A new on-line and time-domain parameter estimation approach of harmonics in electric power system signals is introduced. The developed parametrical identification perspective is based on asymptotic and algebraic estimation techniques, and vibrating signal modeling. Specified harmonics and DC offset component of some measured distorted oscillating signal are reconstructed asymptotically. In this fashion, closed-form explicit formulae to compute into a small window of time, algebraically, on-line and in time-domain, the parameters of amplitude, frequency and phase of harmonics are then derived. Analytical, numerical and experimental results of six and twelve pulses converter reveal the effectiveness and efficiency of the proposed selective estimation approach for harmonics and corresponding parameters of measured oscillating electric signals into an operating frequency bandwidth. Among others, synchronization of power converters or switches to grid without the use of filtering can be achieved with this strategy.