Conversion and control techniques in microgrids

This thesis first proposes a hybrid ac/dc microgrid and its coordination control for reducing the processes of multiple conversions in an individual ac or dc grid. Afterwards, new power electronics interfaces and their corresponding control algorithms for ac type energy resources are studied in ac microgrid. The voltage buck-boost function Z-source indirect matrix converter is proposed to provide interface for ac type distributed generators. Operation of the indirect matrix converter in reverse power flow mode is investigated to produce a boosted gain, whose challenges are addressed with distributed generation suggested as a potential application. Moreover, droop control strategy for two parallel indirect matrix converters is studied in islanded mode. Finally, a novel versatile matrix converter is proposed to integrate two three-phase ac (or hybrid ac/dc) energy resources to the grid. Simulation and experimental results for the proposed design methodologies and control algorithms are provided.Doctor of Philosophy (EEE