Performance analysis of an improved hierarchical droop-based control scheme under topological, parametric and communication uncertainties: Towards a resilient microgrid

Abstract

In this paper, an improved hierarchical droop-based control structure is presented. This improved control structure can resolve the limitation/drawbacks of the previously-reported droop-based control techniques and enhance microgrid stability margin and improve its performance. The conventional hierarchical droop-based structure is re-implemented and some modifications are done. Then, based on the previous researches of the authors, the performance of the proposed control structure is evaluated under topological and parametric uncertainties and delay in communication system. Some special notes and recommendations are provided to draw a picture of realizing a resilient microgrid including a robust hierarchical control system having enough robustness against small and large-signal disturbances, nonlinearities comes from nonlinear loads and nonlinear dynamics of the resources and moreover, the mentioned uncertainties. To demonstrate the effectiveness of the proposed hierarchical controller, time-domain simulation studies have been performed on a microgrid included four units of distributed generation with local loads and in presence of main grid using MATLAB/Simulink software and the results are presneted.