The hybrid energy storage microgrid optimization operation considering the battery health state

To maximize the utilization of renewable energy and the battery lifetime for grid-connected hybrid energy microgrid containing photovoltaic, sodium-sulfur battery and lithium battery, a multi-objective optimization control strategy has been proposed in this paper. Considering the state of charge and lifetime of the energy storage system, the minimization of the power purchase cost of microgrid and the operation cost of energy storage devices has been chosen as the optimization target. Based on the fuzzy decision algorithm, the coordination and tradeoffs have been made between the two optimization targets. Finally, an example based on a real microgrid system validates that this method can efficiently improve the economy of microgrid and the lifetime of energy systems.