Microgrid is new emerging power distribution infrastructures, in smart grid architectures that has the potential to solve major problems arising from distributed generation. Microgrid is defined as the cluster of multiple distributed generators (DGs) that supply electrical energy to consumers with lower power loss. The realization of demand response, efficient energy management, high capability of Distributed Energy Resources (DERs), and high-reliability of electricity delivery leads to a successful Microgrid. In this thesis, DC Microgrid in islanded mode was modelled and controlled and its performance is tested for 24 hours period. The different distributed energy generation systems used are photovoltaic (PV) system, battery energy storage (BESS) system and fuel cell (FC). PV system is modelled by calculating series and shunt resistances of the real life equivalent circuit of the Solar Cell. Four experiments were performed in the Smart Energy lab, RIT Dubai, for the PV systems, to calculate open circuit voltage and short circuit current, to plot the IV characteristics of the PV system, and to track the maximum power point at different irradiances and calculating the daily irradiances. FC modeling was performed in Simulink, the fuel flow was controlled by the output current of the FC to reach the nominal current of 133.3 A and nominal voltage of 45 V. Lithium Ion batteries were used for storing energy generated by the PV system when the supply power exceeds the demand power. Demand power was estimated as the usual daily demand for 24 hours. Controlling these generation systems is performed using converters. Boost Converter used for the PV system was controlled by Maximum Power Point Tracking (MPPT) incremental conductance algorithm to maintain a constant voltage of 300 V at the DC bus despite daily change of the solar power in a day. Boost Buck converter is used to control the charging and discharging processes of the BESS to maintain a constant voltage at the input terminals of the battery to charge it at 130 V and a constant voltage at the DC bus. Boost Converter used for the FC maintained a constant voltage of 100 V.
Library of Congress Subject Headings
Electric power distribution--Direct current; Microgrids (Smart power grids); Electric power systems--Control
Electrical Engineering (MS)
Bahij, Zeina, "DC Microgrid Modeling and Control in Islanded Mode" (2021). Thesis. Rochester Institute of Technology. Accessed from