Fast analysis for power parameters by the Newton method

This paper proposes a method to rapidly analyze power parameters. This method uses two adjacent data to compute the fundamental frequency component of voltage or current. The parameters of fundamental frequency component include frequency, amplitude, and phase. Under the condition of varied parameters, the frequency and the phase are dependent. This method fixes the frequency and computes the amplitude and phase, and then stable results will be obtained. The Newton method, which can rapidly find the parameters, is used to calculate the amplitude and the phase. Harmonic and noise both exist in the practical measured signal; these interferences will influence the calculated result. This paper designs a band pass filter to reduce the interferences and to retain the fundamental frequency component. The method can track the varied parameters of voltage and current, and subsequently, the time-varying impedance will be found.