Advanced Power Electronics Topologies and Control for Electric Distribution and Microgrid Applications

The importance of power electronics is increasingly evident as the world economy becomes more electrified. Power electronics play a key role in enabling renewable energy generation growth. Every year the capacity of electricity generation using renewable sources of energy increases worldwide, this growth is expected to continue for several decades. Power electronic converters are needed to make the integration of such resources a reality. Renewable energy sources such as, solar photovoltaic (PV), wind turbines and micro-turbines are being installed even at distribution centers such as residential areas, industrial locations, etc. When the power generated by these distributed energy resources (DERs) is higher than the local load demand, it is nowadays possible to supply power to the utility grid from the distribution centers and store the excess energy in battery energy storage systems (BESS) for peak shaving and capacity smoothing. Additionally, the possibility of transacting energy between peers in the near future has received increased attention. As DERs penetration increases, the control of the system becomes more challenging for the distribution system operator (DSO), as the intermittent nature of renewable sources can result in grid instability and voltage magnitude variations, limiting the maximum amount of DERs that can be connected to the grid significantly. Therefore, this dissertation presents cutting edge power electronics topologies to enable the increased penetration of DERs in the distribution grid. The first topology accurately controls the voltage magnitude and phase combining phase shifting transformer techniques with AC/AC converters to achieve active and reactive power flow control. This accurate control enables the use of a modified angle droop control scheme, also proposed in this dissertation. The second topology is a self organizing power electronics converter with control intelligence at the edge of the distribution network, intended for residential applications. This topology significantly improves the traditional residential distribution network, allowing massive levels of PV penetration in residential systems, even 100%, promoting further investment on renewables. Every topology includes a suggested application to demonstrate their value for the electrical grid, as well as simulation results. Experimental results are also included for the second topology

Building the Future Internet through FIRE

The Internet as we know it today is the result of a continuous activity for improving network communications, end user services, computational processes and also information technology infrastructures. The Internet has become a critical infrastructure for the human-being by offering complex networking services and end-user applications that all together have transformed all aspects, mainly economical, of our lives. Recently, with the advent of new paradigms and the progress in wireless technology, sensor networks and information systems and also the inexorable shift towards everything connected paradigm, first as known as the Internet of Things and lately envisioning into the Internet of Everything, a data-driven society has been created. In a data-driven society, productivity, knowledge, and experience are dependent on increasingly open, dynamic, interdependent and complex Internet services. The challenge for the Internet of the Future design is to build robust enabling technologies, implement and deploy adaptive systems, to create business opportunities considering increasing uncertainties and emergent systemic behaviors where humans and machines seamlessly cooperate

Building the Future Internet through FIRE

The Internet as we know it today is the result of a continuous activity for improving network communications, end user services, computational processes and also information technology infrastructures. The Internet has become a critical infrastructure for the human-being by offering complex networking services and end-user applications that all together have transformed all aspects, mainly economical, of our lives. Recently, with the advent of new paradigms and the progress in wireless technology, sensor networks and information systems and also the inexorable shift towards everything connected paradigm, first as known as the Internet of Things and lately envisioning into the Internet of Everything, a data-driven society has been created. In a data-driven society, productivity, knowledge, and experience are dependent on increasingly open, dynamic, interdependent and complex Internet services. The challenge for the Internet of the Future design is to build robust enabling technologies, implement and deploy adaptive systems, to create business opportunities considering increasing uncertainties and emergent systemic behaviors where humans and machines seamlessly cooperate