Power management of grid-integrated energy storage batteries with intermittent renewables

摘要

Intensive charging and discharging modes of batteries cause an adverse effect on state of health of grid-integrated energy storage batteries (GIESBs). Furthermore, uncoordinated patterns of charging and discharging the GIESBs are able to expand voltage profiles of power grids beyond their limits, while considering extra generation from photovoltaic arrays (PVs) and wind turbines (WTs). Therefore, a decentralized power management scheme is proposed in this paper to mitigate such impact on grid voltages and to improve the performance of the GIESBs with PVs and WTs. The proposed scheme develops three clusters of different objective functions to coordinate charging and discharging cycles of the GIESBs based on mixed integer linear programming, considering state of charge (SoC) and depth of discharge (DoD) of the batteries. The first cluster minimizes the power-charging cost of the GIESBs by utilizing time of use tariffs. The second cluster minimizes the charging power of the GIESBs, employing per unit generation from PVs and WTs, whereas the third cluster minimizes the discharging power of the GIESBs, using per unit consumption of residential loads. Simulation results of six scenarios show that, although the proposed scheme of the first cluster reduces operational costs of the GIESBs, it cannot maintain system voltages within the limitations. With the second and third clusters, the proposed scheme exhibits a better performance in stabilizing grid voltages, while maintaining the SoC and DoD within their boundaries to underpin state of health of the batteries.