Unbalancing and distorting loads: can they be detected and their detrimental effect be measured?

The proliferation of single-phase, nonlinear, time variant loads is increasing the harmonic and unbalance current and voltage components in the electrical power systems. Since this can be detrimental to the utility´s and other customer´s apparatus, suitable measures should be taken to limit these detrimental effects. The paper discusses a possible theoretical approach to the description of the electrical system behaviour in the presence of harmonic and unbalance components and the methods proposed in the literature to detect the sources producing unbalance and distortion and measure their detrimental effects on the electric power quality