Committee: 

Dr. Saeedifard, Advisor  

Dr. Meliopoulos, Chair

Dr. Divan

Abstract: The objective of this research is to address some of the main challenges in the control and realization of the Multi-Terminal Direct Current (MTDC) grids. Control of the MTDC grids need to be enhanced from two perspectives: i) Sophisticated control methods should be introduced to exploit the  MTDC grids to provide ancillary services for their surrounding AC grids; ii)   Reliable power electronics converters should be integrated to the MTDC grids to enable their interconnection and improve their control and operation. From the first perspective, two challenges are addressed in this research:  i) A Model Predictive Control (MPC)  control method is proposed;  ii)   A control method for frequency support of the AC grids through the MTDC grids is proposed. From the second perspective, analysis of an Isolated Modular Multilevel (IMM) DC-DC converter is presented.  To prove the presented analysis, a scaled-down prototype of this converter is simulated and under construction.