Hassan H. Eldeeb, Abla O. Hariri, Christopher R. Lashway, O. A. Mohammed, “Optimal Sizing of Inverters and Energy Storage for Power Oscillation Limiting in Grid Connected Large Scale Electric Vehicle Park with Renewable Energy ” in 2017 IEEE Transportation electrification Conference and Expo (ITEC), Chicago, IL, USA, June 2017

Abstract:

Power oscillations can result from the expansion of large-scale grid-connected Electric Vehicles (EV) parks fed from photovoltaic (PV) arrays raising concerns about grid stability. This paper addresses the optimal sizing for the energy storage battery, its corresponding DC-DC power converter and the grid tie inverter to satisfy grid requirements and to maximize the profit of a EV park owner under the utility constraints. This was achieved through two stages: probabilistic forecasting of the EV load pattern and optimal sizing of the battery and power converters by the aid of linear programming (LP) problem. Three types of batteries were studied to support the EV park: Sodium Sulfur (NaS), Lead Acid (LA) and Vanadium-Redox (VR). Moreover, a sensitivity analysis was done by investigating the effect of changing the number of grid tie inverters. Results showed the effectiveness of the proposed solution in limiting the power oscillations at the point of common coupling with the grid, and maximizing the EV park’s owner profit. Results revealed as well the superiority of the VR battery for a low number of grid tie inverters while LA was preferable for implementing higher numbers of grid tie inverters the host grid and limiting the power fluctuations at the grid side.