Optimal Sizing of a Wayside PV System for DC Rail Transit Systems: The Case Study of the 3 kV Cagliari - Oristano Traction System

The increasing demand for transportation, along with growing environmental concerns, highlights the importance of electric rail transit systems as a sustainable solution for moving people and goods. While these systems are highly efficient, they also require a significant amount of energy. To both reduce reliance on energy purchased by distribution system operators and mitigate effects on the AC grid, the integration of renewable energy resources (e.g., wind and PV) in the traction system emerges as a valuable solution. This paper specifically focuses on integrating a wayside PV power plant. It is proposed an optimal sizing procedure aimed at maximising the economical investment's revenue while meeting technical constraints related to the limited receptivity of the traction network. Notably, the proposed method is applied to the real case of the Cagliari-Oristano 3 kV DC traction circuit.