Power flow incorporating cost-based droop control strategies for ac autonomous microgrids

Abstract

Several methods of power flow analysis for autonomous microgrids have been suggested; however, the implementation of these methods is challenging because of the lack of a swing bus and droop control characteristics. This paper puts forward an innovative technique for the load flow study of microgrids that autonomously operate according to droop control strategies incorporating cost rather than traditional droop schemes. This approach aims to extend the application of conventional power flow methodologies. In this approach, the incremental cost that is derivative of the fuel cost curve with respect to power output is embedded in droop schemes. The proposed approach deploys the iterative procedure to impose complex power that injects through the swing node to zero, which represents the autonomous operation of microgrids. Test results validate that this approach is exact and straightforward to implement; therefore, it can be highly beneficial for operating and planning microgrids