Isolated UIPC-intertied AC-DC microgrids operation with novel dynamic flexible loads model

•Discussing the islanding operation of hybrid microgrids (HµGs) interconnected by a unified interphase power controller.•A new control structure is proposed for the series power converter of the UIPC which enjoys the robustness of sliding mode control (SMC) concept and adopts a new energy management system (EMS) with embedded decision-making.•A novel generalized dynamic model for flexible loads has been proposed which have been directly controlled through UIPC supervisory system here.•The analytical response of the proposed load model is discussed and further developed using the nonlinear autoregressive-moving-average artificial neural network (ANN) model. The Levenberg-Marquardt learning algorithm is used to train the network based on the model estimation error.•A new model predictive-based optimal control scheme is proposed for the flexible load.