Adaline Based Frequency and Harmonic Estimation

Abstract

This paper combines the LMS algorithm and Adaline network in the estimation of fundamental frequency, harmonic frequency and the amplitude of the harmonic frequency at a faster convergence rate. Power electronic circuits are the main source of harmonics. The estimation of harmonics and their amplitudes in these circuits is very essential for reduction of harmonics. Using SIMULINK an AC-DC Converter and a AC Voltage Controller circuit are designed. The voltage and current signals of these circuits are used for applying the proposed technique. Fixed step size, optimal variable step size and recurrent variable step size algorithms combined with Adaline network are the techniques to be applied for the power electronic circuitry introducing harmonics. The distorted signals are then analyzed for the calculation of the magnitudes of the harmonics amplitude and the fundamental frequency traction by the above three algorithms. For the sake of comparison the magnitudes are estimated by the Fast Fourier Transform technique also. Then the results of the three algorithms with the Adaline network and the results of FFT technique are compared and tabulated.