Robust Harmonic Estimation Using Forgetting Factor Rls
ROBUST HARMONIC ESTIMATION USING
FORGETTING FACTOR RLS
H.K.SAHOO
POOJA SHARMA
Dept. of Electronics and Telecommunication
IIIT, Bhubaneswar
India
Email: harish@iiit-bh.ac.in
Dept. of Electronics and Telecommunication
BIT, Mesra, India
Email: haipoo29@gmail.com
N.P.RATH
Dept. of Electronics and Telecommunication
VSSUT, Burla, India
Email: n_p_rath@hotmail.com
Abstract— The prime reasons for power quality degradation include voltage sag, swell and momentary interruptions and also the presence of harmonics. Thus accurate computation of harmonics is really a challenging problem in power system. Many algorithms have been proposed for harmonic estimation to improve the power quality. In this paper the Forgetting Factor RLS (FFRLS) approach has been considered to estimate not only voltage sag,swell,momentary interruption but also the amplitudes and phases of harmonics in case of time varying power signals in presence of White Gaussian Noise. Also comparison results with LMS and NLMS algorithms are presented to show the effectiveness of the proposed RLS algorithm.
Keywords- RLS, LMS, NLMS, Harmonic Estimation, White
Gaussian Noise
I.
INTRODUCTION
The wide spread applications of electronically controlled loads have increased the harmonic distortion in power system voltage and current waveforms. As power semiconductors are switched on and off at different points on the voltage waveform, damped high frequency transients are generated. If switching occurs at the same points on each cycle, the transient becomes periodic. This transient whose frequency is not a multiple of fundamental frequency is non-stationary.
Consequently voltage and current waveforms of a distribution or transmission system are not pure sinusoids, but may consist of a combination of fundamental frequency, harmonics and high frequency transients. Also many of power system loads, especially industrial loads are dynamic in nature, which implies time
FORGETTING FACTOR RLS
H.K.SAHOO
POOJA SHARMA
Dept. of Electronics and Telecommunication
IIIT, Bhubaneswar
India
Email: harish@iiit-bh.ac.in
Dept. of Electronics and Telecommunication
BIT, Mesra, India
Email: haipoo29@gmail.com
N.P.RATH
Dept. of Electronics and Telecommunication
VSSUT, Burla, India
Email: n_p_rath@hotmail.com
Abstract— The prime reasons for power quality degradation include voltage sag, swell and momentary interruptions and also the presence of harmonics. Thus accurate computation of harmonics is really a challenging problem in power system. Many algorithms have been proposed for harmonic estimation to improve the power quality. In this paper the Forgetting Factor RLS (FFRLS) approach has been considered to estimate not only voltage sag,swell,momentary interruption but also the amplitudes and phases of harmonics in case of time varying power signals in presence of White Gaussian Noise. Also comparison results with LMS and NLMS algorithms are presented to show the effectiveness of the proposed RLS algorithm.
Keywords- RLS, LMS, NLMS, Harmonic Estimation, White
Gaussian Noise
I.
INTRODUCTION
The wide spread applications of electronically controlled loads have increased the harmonic distortion in power system voltage and current waveforms. As power semiconductors are switched on and off at different points on the voltage waveform, damped high frequency transients are generated. If switching occurs at the same points on each cycle, the transient becomes periodic. This transient whose frequency is not a multiple of fundamental frequency is non-stationary.
Consequently voltage and current waveforms of a distribution or transmission system are not pure sinusoids, but may consist of a combination of fundamental frequency, harmonics and high frequency transients. Also many of power system loads, especially industrial loads are dynamic in nature, which implies time
References: Algorithm” Elsevier Science Electric Power System Research 79(2009) 107-116. Letters IEEE, vol. 11, pp. 736-739, Sept. 2004.