Unit Sizing of Grid Connected Micro-Grid Using Model-Free Optimization Considering Interruptible Loads.

The present paper presents a methodology to perform the optimal sizing of grid connected micro-grid that consists of wind turbines, photovoltaic panels, fuel cell and the capacities of battery bank, interruptible and uninterruptible loads. Also Micro-grid can exchange power with grid. When total of produced power in micro-grid plus purchased power from grid can not satisfy demand, first interruptible and then uninterruptible loads are shed. In this paper, the problem is formulated as a nonlinear integer minimization problem which minimizes the sum of the total capital, operational and maintenance and replacement cost of DERs, penalty for interrupted loads, subject to constraints such as energy limits of each DER, limits of exchanged power, interruptible and uninterruptible loads. This paper proposes Particle Swarm Optimization (PSO) for solving this minimization problem. The proposed methodology was used to design micro-grid for northwest of Iran. The simulation studies have shown that the proposed methodology provides excellent convergence and feasible optimum solution for sizing of islanded micro-grids using particle swarm optimization. In this paper Forced Outage Ratio (FOR) of each component and some notions of reliability are considered for micro-grid, and the effect of reliability and FOR on total cost of micro-grid is evaluated. [ABSTRACT FROM AUTHOR]