Optimal operational planning for PV-Wind-Diesel-battery microgrid

Global optimal solution to microgrid operational planning problem can be obtained by using a Modified Optimal Dispatch Strategy (MODS) which combines Load Following Dispatch Strategy (LFDS) and Cycle Charging Dispatch Strategy (CCDS). Most of the dispatching strategies formulated in microgrid operational planning problem may lead to solutions which are not necessarily global optimal. In this work, microgrid operational planning problem is formulated as Mixed-Integer Linear Programming (MILP) model which includes MODS, LFDS and CCDS. The model includes all constraints for Diesel Generators (DGs), Storage Battery (SB) bank and reserve requirements. Contrary to the simulation-based approach found in many studies, we adopt mathematical optimization approach and implement the model in General Algebraic Modelling System (GAMS). The model is applied to plan day-ahead operation of a small microgrid in South Sudan. Optimization is performed by using CPLEX 12 solver. MODS is found to give optimal operation plan which has minimum daily operation cost as compared to LFDS and CCDS. This model can be used to plan day-ahead operation of any hybrid PV-Wind-Diesel-Storage microgrid, enabling the operator to consider system reliability by specifying reserve requirements.