Technical Lecture Session
DC Microgrids, Distributed control, Fixed-Time consensus protocol, Economic operation.
This paper presents a fully distributed fixed-time cooperative secondary controller for DC microgrids (MGs) to solve the economic dispatch problem (EDP) in a fixed-time manner. It contains both power optimizer and voltage regulator while a sparse communication network is modeled to convey the needed information between DGs based on peer-to-peer communication protocol. Based on equal incremental costs (ICs) scheme, the power optimizer sufficiently guarantees the optimum load power allocation between DGs within a predefined settling time. Additionally, the voltage regulator is mainly answerable to restore MG's average voltage to the nominal value and achieves the equilibrium between generation and demand using fixed-time average consensus protocol. The distinctive advantage of the developed controller is that the objectives can be realized within a fixed-time which is independent of the initial states and possible to be predesigned offline. Small scale islanded DC MG prototype has been developed to verify the efficacy of the proposed controller in case of load variations and communication failures and the plug-n-play capability is demonstrated as well.