Print Email Facebook Twitter Control for Bipolar DC Microgrid and DC/DC Bidirectional Converter in Energy Access Context Title Control for Bipolar DC Microgrid and DC/DC Bidirectional Converter in Energy Access Context Author Zhou, Xiaochuan (TU Delft Electrical Engineering, Mathematics and Computer Science) Contributor Qin, Z. (mentor) Mackay, Laurens (graduation committee) Degree granting institution Delft University of Technology Programme Electrical Engineering | Electrical Power Engineering Date 2023-08-23 Abstract Rural electrification remains a significant challenge for engineers, given its intricate relationship with multiple issues, including geographical constraints and underdeveloped infrastructural provisions. As a result, with the development of Solar Home Systems (SHS) and direct current (DC) microgrids, DC systems for energy access have emerged as a promising solution. In this context, a bidirectional DC/DC converter serves as a bridge connecting the SHS and the grid. Thus, it is important to design a converter's control mechanism to ensure a smooth and efficient exchange of power in both directions. Beyond this aspect, the system perspective involves the coordination of photovoltaic (PV), battery storage, and grid power supply priorities within the SHS. Consequently, this thesis centers its attention on two objectives: the control of the bidirectional DC/DC converter and the system-level control of the DC microgrid.To ensure high efficiency under variable loads and smooth transitions between two directional operations, this thesis proposes and evaluates a novel control methodology. Transfer functions are derived through mathematical modeling and PI parameters are determined by analyzing Bode-Plots. This work also shows the simulation and testing results. Both results demonstrate that the proposed control method achieves a high efficiency under light load conditions, maintaining a stable output voltage despite load power dramatic fluctuations.Analysis of energy exchange between the DC microgrid and SHS involves a bipolar DC microgrid model based on an established grid in Matlab/Simulink. Employing droop control, which is a widely used decentralized strategy, for each converter within the grid. To ensure priority order of power supply in the system, a system-level decentralized control methodology is developed, assuming internal communication within the SHS. Through simulation, the priority order of PV, battery, and grid is verified, along with the impact of dynamic shifts between scenarios on the load. However, given the absence of communication devices in the existing SHS, an alternate decentralized coordinated control strategy is developed and simulated, without direct communication interfaces. Simulation results demonstrate that the SHS bus voltage remains stable even with power supply changes. Subject Rural ElectrificationBipolar DC MicrogridDual Active Half bridge (DAHB)ZVSDecentralized ControlBurst Mode OperationDroop ControlPI Control To reference this document use: http://resolver.tudelft.nl/uuid:1534f971-06aa-45ac-8c95-1504aa6878cb Embargo date 2023-08-23 Coordinates 52.000999996,4.370165186 Part of collection Student theses Document type master thesis Rights © 2023 Xiaochuan Zhou Files PDF MSc_Thesis_Xiaochuan_Zhou.pdf 30.99 MB Close viewer /islandora/object/uuid:1534f971-06aa-45ac-8c95-1504aa6878cb/datastream/OBJ/view