Analysis of the impact caused by low voltage customers harmonic generation in the distribution grid by a harmonic three-phase load flow based on the current summation

This article accomplishes an evaluation of the harmonic impacts caused in the distribution grid by the secondary distribution grid customers using a developed three-phase harmonic load flow algorithm. The algorithm is based on the current summation method and incorporates the concept of PV buses in the load flow solution to make the proposed methodology adequate to treat with distributed generation connected to the low voltage distribution grid. A real case study of a distribution feeder with 92 transformers of different capacities and different types of load is presented. Measurements were carried out in 15 transformers strategically selected so as to provide a representative sample of the harmonic injection profile of the feeder.