A New Digital Signal Processing Based Approach for Evaluation of Reactive Power and Energy in Power Distribution Systems

This paper presents a new analogue and digital signal processing (DSP) techniques for the measurement of reactive power (RP) in the sinusoidal conditions. Proposed approach simplifies the multiplication procedure to evaluate the reactive components from the instantaneous power signal. The advantages of the proposed approaches for the RP evaluation have been verified by experimental studies. One of these advantages is that in contrast to the known existing methods which involve time delay or shifting of the input signal, the proposed technique does not require the time delay of the current signal to the pi/2 with respect to the voltage signal. Another advantage is related to the computational saving properties of the proposed approach coming from use of the Walsh transform (WT) based signal processing algorithm. The validity and effectiveness of the suggested technique for evaluation of the RP components of the electrical power have been tested by use of the simulation tool developed on the base of "Matlab".