A new formulation of line voltage drop in unbalanced and distorted systems

The classical problem of three-phase voltage drop calculation, well established in the case of sinusoidal positive sequence systems, is extended in the paper with regard to unbalanced and distorted power systems. The adoption of the Park theory permits the introduction of the imaginary power in the voltage drop expression. The imaginary power generalizes the role of the reactive power in the classical treatment and permits to quantifies in one term only the effects on the voltage drop due simultaneously to the load instantaneous stored energy and to the presence of harmonic and sequence components. Two examples are reported in order to testify, in the case of unbalances and distortions, the effectiveness of the proposed formulation