Methodology for analyzing the impact of electric vehicles on distribution networks: a theoretical approach

The growing demand for electricity and the rapid proliferation of electric vehicles present significant challenges for low-voltage distribution networks, particularly their critical components, such as distribution transformers. Infrastructure designed for traditional loads faces the risk of overloading due to high peak loads caused by uncontrolled electric vehicles charging. This paper develops a comprehensive methodological approach to assessing the impact of charging processes on the lifespan of distribution transformers, considering various levels of electric vehicles penetration, combinations of electrical loads, and local operating conditions. The study is based on the hypothesis that is optimizing charging schedules, particularly shifting charging to off-peak hours, can significantly reduce transformer ageing rates and enhance the reliability of the power supply. The proposed methodology employs a fuzzy logic-based model that integrates numerous factors affecting transformer performance, including ambient temperature, harmonic distortion, reactive power compensation, reverse energy flows from photovoltaic installations, and overload risks. The study examines charging scenarios on demand, off-peak charging, and a combined mode with vehicle-to-home (V2H) technology, which integrates electric vehicles as a backup energy source for household needs. The results demonstrate that such approaches can minimize network upgrade costs while maintaining network stability even under high electric vehicles penetration levels. The presented methodology provides a foundation for developing adaptive energy resource management strategies aimed at improving distribution system resilience, extending transformer lifespan, and enhancing the economic efficiency of the infrastructure.