Physical time domain representation of powers in linear and nonlinear electrical circuits

This paper presents a time domain model for the representation of powers in linear and nonlinear electrical circuits. The model can account, in a physical (or engineering) sense, for “active and reactive powers” as functions of time. The model is based on the time domain decomposition of the instantaneous power p(t) into two components: p(f)=a(t)+r(t). Where, a(t) represents the instantaneous power consumed by the (linear or nonlinear) load. The information regarding the store/restore process is contained in r(t). In contrast with the traditional frequency domain model, in which powers are defined orthogonally (i.e. S²=P²+Q²+D² +…) and therefore they do not interact with each other, the proposed model permits the interaction of active and reactive powers at every instant. Using the model of the paper, the authors can obtain the instantaneous power needed for compensation of both wave shape and power factor