Investigation of electric vehicle grid support capability

摘要

Within the scope of the e-SolCar project, which aims to improve the urban gridstructures in view of the future challenges in photovoltaic generation and loadsfrom e-mobility, the fleet consisting of 41 battery electric vehicles (BEV) has beenput into operation. At the central campus of the BTU Cottbus, 15 of them are used as test objects. TheseBEV are supplied through 100 kW peak PV, stationary batteries (of 2000kWhinstalled capacity) or the main grid, depending on system situation. In the nearfuture, these electric cars will also be able to give the stored energy back to the grid(V2G). This ability will be applied in order to check the technical feasibility and thepotential contribution to grid stability, since electric cars will be used not only asloads but also as positive and negative control powers. After a fleet testing phase of almost one year, we were able toanalyze some acquired data. For instance, thecalculation of the real available capacity has been contrasted with the theoreticallyinstalled battery capacity. Furthermore, we took a closer look at particularities ofthe mobile storage system, such as experiences with charging electric vehicles (BatteryManagement System), handling high-voltage batteries, problems, advantages and disadvantages of the mobile storage system, recommendations andnecessary improvements. Finally, the results of the cooperation between electric car manufacturerGerman-E-Cars R&D and BTU researchers in the field of communicationbetween grid system and BEV as well as application of V2G are presented.