Design LQR and PID Controller for Optimal Load Sharing of an Electrical Microgrid

ABSTRACT: Interconnection of distributed generators (DGs) to the utility grid through power electronic converters has raised concern about proper load sharing between different distributed generators and the grid. In this paper control strategies for proper load sharing between utility and parallel converter connected in a microgrid and supplied by DG are described. The DG has local loads that are very close to it. These loads can be unbalanced and/or non-linear. A control method is proposed to load balancing and proper load sharing in both islanded and grid-connected modes. This method helps DG to compensate the effects of unbalance and non-linearity of the local loads using LQR controller and then, using a novel PSO algorithm designs a PID controller for proper load sharing between utility and DG. Both grid-connected and island mode responses are considered. The efficiency of the controller has been verified through simulations for various operating Conditions Using Matlab-Simulink.