Analysis of acceptable capacity of microgrid connected to the main power grid

It has been one of the most effective way to fully develop the Distributed Generation (DG) when it is connected to the main power grid by way of microgrid, supporting each other with the main power grid. The research of the microgrid size and the specification of its acceptable capacity with respect to the main power grid will be beneficial to the best utilization of renewable energy resources, achieving the coordinated development between DG and the main power grid. What's more, this will be a guide and specification for the connection of the microgrid to the main power grid, ensuring operational security, stability, and economical efficiency. This paper started with characteristics of microgrid interconnected system, relative issues when microgrid connected and its impacts upon the main power grid were discussed. Combining with the analysis, means of defining the acceptable capacity of microgrid connected to the main power grid were introduced in this paper. Finally, simulations were carried out using MATLAB/SIMULINK tool, of which the result presented the acceptable capacity of microgrid connected to the main power grid.