Characterization of non-linear load behavior

This paper studies the univocal characterization of non-linear load behavior from normalized parameters that are called invariants. The model of four non-linear loads (single- and three-phase uncontrolled rectifiers, six pulse rectifiers and discharge lamps) is analyzed to obtain their invariants by the normalization method. These invariants are the minimum number of parameters characterizing non-linear loads completely, and they can be used to carry out practical studies of these loads. To show the usefulness of the invariants obtained in practical applications, the influence of these invariants on the behavior of non-linear loads is studied and the harmonic cancellation between them is analyzed with four laboratory tests.