A new Taylor-LMS adaptive filter for parameter estimation of power signals including distributed generation systems

Abstract

Frequency and phasor measurement of time-varying signals has assumed great importance for phasor measurement units for wide area power networks in micro and smart grid environments. It is well known that the power signals undergo dynamic transitions during power quality and fault type disturbances. Also accurate estimation of amplitude, phase and frequency of a sinusoid in the presence of harmonics/inter harmonics and noise plays an important role in wide variety of power system applications, like protection, control and state monitoring. One of the widely used approach like the Fourier linear combiners becomes ineffective to track the sudden changes in the power signal amplitude, phase, and frequency in the presence noise and distortions. This paper, therefore, presents a new adaptive filter for estimating the frequency and phasors of sinusoids mixed with decaying dc and harmonic components undergoing sudden transitions. The filter is based on a quadratic polynomial signal model whose parameters are estimated using a variable step continuous p-norm LMS algorithm. Extensive computer simulations have been carried out with synthetic signals to demonstrate the viability of this new approach. Further signals obtained from a distributed generation system in MATLAB/SIMULINK environment are used for frequency, fundamental and harmonic phasor estimation.