According to the structural and operational requirements of a grid-connected AC/DC hybrid microgrid

four levels of operational modes are proposed. In order to reflect the nonlinear characteristics of energy storage loss

an integral calculation model for energy storage loss cost is proposed. The minimization of daily operational cost is taken as the objective function

which consists of the cost of equipment maintenance

energy storage loss

converter loss

and electricity purchasing and selling cost. And the economic optimization model of the AC/DC hybrid microgrid is developed. The results of actual examples show that the coupling relationship between economic parameters determines the operational modes of AC/DC hybrid microgrid. The analysis results verify the rationality of the proposed operational modes of AC/DC hybrid microgrid

economic optimization model and energy storage loss integration model.