Energy management and modeling of a grid-connected BIPV system with battery energy storage

The increased penetration of renewables in power system generation has introduced several stability issues to existing power systems. Their intermittent nature in combination with the lack of rotational inertia made system operation even more difficult and frequency/voltage fluctuations larger. Storage systems have been identified as an ideal solution for mitigating these problems since their integration across the grid can reduce generation-load imbalances and assist in primary frequency regulation. Considering the importance storage systems have gained during the last years, in this paper we propose an energy management algorithm for a grid-connected PV system with battery storage. This model contains a Building Integrated Photovoltaic (BIPV) system connected to the grid through a DC-DC boost converter, a DC-AC inverter and a battery storage system in active parallel configuration. Considering that the consumption of the building is satisfied from either the PV, the low voltage grid and/or the battery storage system, a specific energy management algorithm is presented for this model, in order to provide an efficient power flow between the aforementioned sources and the building load. The proposed model is implemented and verified through several simulations in Matlab/Simulink.