PhD ThesesThe intermittent nature of renewable energy sources (RES) such as wind turbines
and photovoltaic panels, requires advanced control systems to provide the
balance between energy supply and demand in any power system. For better
management of power quality and security issues, energy storage systems (ESSs)
are deployed to compensate for the temporary mismatch of supply and demand.
Furthermore, in rural areas with no connection to the main grid, ESSs such as
batteries are deployed in large quantities as a solution for temporary power stabilization
during RES unavailability. However, the control complexity of the
power system increases as more ESSs are getting installed due to the need for
coordination of the power transfer among them.
This thesis undertakes a thorough analysis of distributed control and state
estimation designs for direct current (DC) microgrids with ESSs based on constrained
communication networks. The developed distributed control and estimation
strategies are designed for operation over constrained communication
networks. They don't require a central coordinator for synchronization of the
control tasks between the ESSs. This forms a multi-agent environment where
the controllers cooperatively achieve the DC microgrid objectives, i.e. voltage
stabilization, proportional power-sharing, and balancing of ESSs' energy level.
To overcome the communication network constraints, event-based controllers
and estimators are designed, which e ectively reduce the network tra c and as
a result, provide higher throughput with reduced delays for the real-time control
loops of the DC microgrids. The controllers are designed to be distributed,
leading to use cases such as autonomous islanded microgrids, smart villages,
and plug-and-play mobile microgrids. The feasibility and performance of the
proposed control and estimation strategies are con rmed in several experimental
test benches by showing the higher reliability and robustness in the delivered
power quality. The results have shown considerable reduction in the network
tra c, meanwhile the control system provided high performance in terms of
stability, robustness, power quality and endurabilit
