A Simple Model for Harmonics in Electrical Distribution Networks

A modularized approach to modeling of harmonics in electrical distribution networks at steady state is presented. It is based on harmonic balance and exploits that the loads in a distribution network are connected in parallel in such a way that their operating conditions are approximately known in advance (e.g. 230 V, 50 Hz) and the harmonic distortion of the voltage is limited. The model for a component is given by a linear relation between the Fourier coefficients of the deviations from nominal current and voltage. The linear relationship implies that aggregation of loads and network solving are a matter of solving linear equation systems. This leads to fast calculations without convergence problems