Study of the impact of grid connected PV system on PQ through a comparative analysis by scenarios

Over the last years, the implementation of PV systems has been growing rapidly. The PV penetration in power systems means new concerns about their impacts on the power quality (PQ) of the distribution networks. Both, intermittent nature of solar PV and electronic power devices used in PV systems could affect the voltage profile, harmonic distortions, and voltage unbalance, among others. The aim of this paper is to evaluate and quantify the impact of PV systems on some PQ parameters of low voltage (LV) distribution networks. This, by performing a comparative statistical analysis through the application of hypothesis testing of the difference between two population means, where those populations are the data with and without PV generation classified into PV power and load power scenarios. The methodology covers the selection of PQ parameters and their monitoring, the application of a scenario matrix for grouping data with similar load and PV injection conditions, and, lastly, the Wilcoxon rank sum test (non-parametric test) is applied. This methodology is applied to evaluate the effect of the integration of a PV system (9.8 kWp) on the LV network of a university building.