Modelling and assessment of the combined technical impact of electric vehicles and photovoltaic generation in radial distribution systems

Photovoltaics (PVs) provide new opportunities for radial distribution systems (RDSs) that feed electric vehicle charging stations (EVCSs). However, the accurate assessment of the combined technical impact is problematic because of the uncertainties of sources/loads. In previous research, we developed a technique to assess the impact of PV generation. This new study presents a general analytical technique (GAT) that evaluates the combined impact for an extended time frame. Specifically, the GAT effectively assesses the fulfilment of technical requirements for weekly RDS operating variables as specified in regulations. As our main objective is to improve the assessment accuracy of the EV and PV interaction in RDSs, the weekly assessment was extended to a one-year time period, during which it is possible to capture the total uncertainty. Also, correlation of input variables is handled. The computational cost of the GAT is lower than that associated with Monte-Carlo simulation, which is used to confirm the GAT accuracy. Although the results focus on an RDS located in Spain, GAT is applicable to any RDS and is scalable to different penetration levels. The numerical results show the impact of different correlated and non-correlated case studies on the voltage profile, apparent power flow in lines, and real loss.