The optimum scheduling of preplanned microgrid island using response surface methodology

The preplanned islanding of grid-connected microgrid (MG) enables the interactions between the microgrid and several forms of scheduled operations in the upstream distribution network. In this paper, the preplanned islanding schemes of microgrid are optimally scheduled considering their coordination with the distribution system maintenance. In the framework of the presented research, the distributed generators and energy storage system are optimally dispatched in each islanding scheme, which aims at the minimization of operation cost and load curtailment, meanwhile incorporating a variety of system and components´ constraints in both grid-connected and islanding modes. Then, the optimum scheduling of preplanned islanding is realized by response surface methodology. In the proposed method, the simulation results of day-ahead economic dispatch are utilized to fit the second-order polynomial function, aided by a series of design methods. Ultimately, the established model is solved to obtain the optimal starting time and duration of preplanned islanding. Numerical results show that the preplanned islanding scheme can be accurately optimized by the proposed method. In this method, the number of simulations required for the optimization is reduced, while the solving accuracy is close to the enumeration method.