Technical data analysis and power grid effects of fast charging processes of electric vehicles
The competitiveness of electromobility is strongly influenced by the charging procedure, whereby particularly fast charging emerged as key factor for user adaptation. At the same time, a rising number of used electric vehicles (EVs) would considerably overstrain the existing energy infrastructure. Especially the short-term peaks arising from fast charging technologies are most challenging in this regard. To assess the impact of the rising EV loads on the distribution network several methods are suitable to gain a better understanding, due to which especially computer-aided simulations became a widespread approach. In contrast to complex battery and energy load simulations, this paper aims to evaluate electromobile grid impacts in high accuracy by means of extensive field tests. The present paper provides new insights in load behaviors of different EV-types by depicting influencing factors like state of charge (SOC) and temperature dependencies. A thorough analysis of 263 charging events is carried out along with an evaluation of the system load on the Fraunhofer IAO Micro Smart Grid to outline the challenges future power grids are faced with. The main findings of this work are, that each EV model features a distinct charging profile, by which a progression with the charging and battery technology can be noticed. Additionally, a strong difference between charging events of the several seasons of the year was shown with a decrease of charging power in winter. It can be concluded, that fast charging imposes a huge burden on the energy grid due to the high peak loads, which is the main challenge for the widening EV fast charging implementation.