Abstract:

Amid growing concerns about climate change, electricity-powered transportation systems stand out as an opportunity to help in reducing fuel consumption. Electric vehicles (EVs) would connect to the grid using clean, renewable electricity; however, the interconnection between EVs and the grid brings about new challenges for traditional power systems. Plug-in hybrid and plug-in EVs have become more prevalent in the system; therefore, their impacts and benefits are also of concern. Among these concerns is the detailed analysis of EVs' impact on short-circuit levels in microgrid protection schemes. In this context, the main contribution of this paper is a detailed evaluation of the impact of EVs on the short-circuit levels and protection coordination schemes in microgrids. For this purpose, a methodology was proposed to measure the impact of EVs on the protection coordination schemes in microgrids using different evaluation indices. The proposed approach was validated on a benchmark IEC microgrid considering different operative scenarios that envisage several levels of EV penetration. The results evidenced the applicability of the proposed approach and allow conclude that the incorporation of EVs in microgrids impacts the performance of the protection schemes, specifically with respect to short-circuit levels.