Harmonic domain modeling of a distribution system using the DIgSILENT PowerFactory software

The first part of this paper presents the comparison between two models of distribution system created in computer simulation software PowerFactory (PF). Model A is an existing simplified equivalent model of the distribution system used by transmission system operator (TSO) Eltra for balanced load-flow calculation and stability studies. Model B is accurate model of the distribution system created on the basis of the detailed data of the investigated network and is used as a reference. The harmonic impedance of the two models is compared. In the second part of the paper, the sensitivity of the harmonic impedance to basic system parameters (load active power, motor load fraction and reactive power of PFC capacitors) is analyzed.