Optimal management of micro grid in restructured environment

Electric utility deregulation and power system restructuring encourage micro grids penetration into distribution networks. Micro grids are low voltage distribution networks that are designed to supply electric and heat loads for small communities. A micro grid which is aggregation of various distributed generators (DGs), storage devices and controllable loads, can be operated and dispatched flexibly. Micro grids can work in an interconnected or autonomous mode. In this paper, component models of micro grids are determined by using real data and cost of micro grid is minimized in order to determine the optimal generation of each DG and the amount of controllable loads during a day. The problem formulation includes purchased energy from the main grid, DGs' operational cost, start-up and shut-down costs, and finally the cost of interrupted loads. Also, the ramp rate and other constrains of each DG are considered. The micro gird considered in this paper consists of a wind turbine, a micro turbine, a photovoltaic array and a fuel cell.