Semnan University International Journal of Nonlinear Analysis and Applications 2008-6822 10 2 2019 12 01 A Novel Robust Hierarchical Consensus Algorithm with Application in DC Nanogrids Coordination 97 110 4178 10.22075/ijnaa.2019.4178 EN Ahmadreza Ghaznavi Faculty of Electrical Engineering, Yazd University, Yazd, Iran SMT Almodarresi Faculty of Electrical Engineering, Yazd University, Yazd, Iran Journal Article 2017 12 15 This research investigates the delay sensitivity of discrete-time consensus among agents which communicate over a scale-free network with hubs. In this paper, a novel hierarchical consensus algorithm, based on the idea of virtual communication graph degree reduction, is proposed. As a result, a significant consensus speed gain is obtained which provides a potential time margin for applying cyber-physical techniques that cause systematic input delay. This approach provides robustness and resiliency in case of any communication topology disturbance during cyber- physical attacks or plug-and-play events. The feasibility of plug- and-play, which has the potential to increase the input delay, is presented based on the gained margin as a sample scenario. The algorithm application in the coordination of distributed photovoltaic resources of several nano-grids communicating over a scale-free network, is assessed via simulation as well. https://ijnaa.semnan.ac.ir/article_4178_e2cb52dc5f3439b05970db7f87599e80.pdf