Current Measurement in Wide Band-Gap Power Devices for Characterization and Fast Overcurrent Protection

The advent of new materials, such as silicon carbide (SiC) and gallium nitride (GaN), is driving significant changes in the power electronics industry. These materials allow the fabrication of power devices with reduced leakage, lower power consumption, higher power density, and the capacity to operate at higher frequencies compared to their silicon counterparts. This implies that power converters can be manufactured in a smaller, lighter, more efficient, and more powerful form, while occupying a smaller volume. Conversely, the deployment of wide bandgap semiconductors, due to their enhanced switching speed, has introduced new challenges for measurement equipment. In order to guarantee the dependability of newly developed converters, measurement systems must possess a greater bandwidth and be capable of handling high current and voltage ratings while remaining compact. As one of the primary challenge in this field is the development of a current measurement scheme that meets all the new requirements, this thesis focuses on developing new solutions for measuring current in wide bandgap power electronic systems. Specifically, the research addresses the limitations of using SMD shunts in the latest generation converters and proposes solutions to overcome them. The proposed approaches are evaluated based on their potential, cost effectiveness and ease of implementation, taking into account their practical implications. The main contribution has concerned the development of simple and effectiveness SMD shunt resistor based current measurement networks and their implementation to realize overcurrent/short-circuit protection systems with incredibly time responses.