Energy management of a microgrid via parametric programming

An energy management system (EMS) for efficient and tractable coordination of distributed energy sources in a residential level microgrid is presented. Sources of energy include renewable (solar photovoltaic and wind turbine), conventional systems (microturbine and utility grid connection) and battery energy storage system. The overall problem is formulated using parametric mixed-integer linear programming (p-MILP) via parameterizations of the uncertain coordinates of the wind and solar resources. This results in a bi-level optimization problem, where choice of the parameterization scheme is made at the upper level while system operation decisions are made at the lower level. The p-MILP formulation leads to significant improvements in uncertainty management, solution quality and computational burden; by easing dependency on meteorological information and avoiding the multiple computational cycles of the traditional online optimization techniques. The problem is solved offline on a day-ahead basis, allowing online implementation to be achieved via real-time system state updates. The proposed parametric programming approach extends the state-of-the-art in microgrid energy management methods, and the simulation evidence its feasibility and effectiveness.