Enabling miniaturized grid-interface power conversion

Abstract

Many of the most critical challenges of the twenty-first century revolve around energy and its management. Improved performance (efficiency, density) in electrical energy management systems require advancements in a number of areas - semiconductor devices, passive energy storage components, and a variety of circuit- and system-level concerns. The sections of this thesis are somewhat distinct and may find application in a great variety of circumstances. Nevertheless, they can be understood as contributions to a single application system: a grid-interface power converter. These kinds of converters have several unique aspects that make them good targets for research, including a heavy reliance on magnetic components, relatively high voltages for application of emerging GaN transistors, wide range of operating voltages and powers, and a twice-line-frequency energy storage component that is difficult to miniaturize. This thesis will present a high-frequency inductor structure with greatly improved density, an exploration of the limits of magnetic-based current sensing, a method for characterizing GaN losses with large-signal excitations, a control approach for miniaturizing grid-interface energy buffers, and a grid-interface circuit with several advantages over the state of the art.