Trends in harmonic emission assessment is evolving towards Admittance Loci.

For example, Transmission System Operators from Brazil (ONS) and UK (NGC) require to study the worst case scenario depending on possible contingencies in the neighborhood grid.

DIgSILENT Ibérica has already studied several installations with this method. DIgSILENT PowerFactory analysis functions like Frequency Sweep and Contingency Calculation are combined to compute the Admittance Loci. The worst case admittance, for each harmonic, is automatically reported and used to compute the harmonic voltage distortion at the point of interest.