Determining the reactive power from the active power in single phase systems using the extended newton-phaselet method

This paper presents the performance evaluation of the extended Newton-phaselet method for determining the reactive power using only the active power in single phase systems. The presented method is structured to use one value of the active power P to calculate one value of the apparent power |S̅|, while it employs 6 phaselet frames to calculate a value of the angle θ (the phase of S̅). Calculated |S̅| and θ are used to determine a value of the active power P_C, which is compared to P in order to adjust |S̅| for the next Newton iteration. Furthermore, calculated values of P_C, |S̅|, and θ at each iteration are employed to determine a value of the reactive power Q_C at that iteration. The extended Newton-phaselet method is implemented for performance evaluation using the measured active power supplied to different 1φ loads. Performance results of the developed method demonstrate simple implementation and high accuracy with minor sensitivity to load types or power factor status (lagging or leading).