Advancements in wide band-gap (WBG) power semiconductors will play a critical role in a wide spectrum of power electronics systems and applications. Compared to their current counterparts, WBG devices are capable of higher blocking voltage, switching frequencies, power handling capacity and thermal conductivity, which can motivate migration toward electrification of transportation and a highly automated modern grid, among other applications. In harsh operating environments, these components are subjected to various mechanical and electrical stresses, wear out, and vibration that contribute to increased equipment failure potential, where a failed component can cause unexpected interruptions, serious safety issues, or easily lead to millions of dollars in repair costs. The proposed research plan will help achieve self-monitoring reliable WBG power electronics systems by providing condition monitoring tools that broaden understanding of the WBG device degradation process, incipient fault diagnosis and remaining useful lifetime prediction. Establishing an advanced reliability framework will lead to new scientific tools, accelerating deployment of WBG systems in grid integration, electric transportation and defense systems. The long-term vision and career plan of the PI is to integrate several thrusts relevant to this program, namely: WBG power semiconductors, power electronics systems, and fault diagnosis/prognosis theory as core disciplines. On the educational side, the goal is to develop educational materials that provide an integrated view of relevant fields for training the next generation of power electronics engineers. The PI will continue to reach out to high school students with tangible, project centric experience in his laboratory. The technologies and tangible applications developed as a result of the proposed plan will serve as instruments to inspire and encourage students to pursue STEM careers.
More specifically, the proposal aims to investigate incipient faults of wide band-gap semiconductor devices and create online fault diagnosis / failure prognosis tools to establish early warning systems for future power electronics systems. The rapid and widespread deployment of wide band-gap semiconductors raises significant reliability concerns, particularly for mission and safety critical systems due to limited field data and potential uncertainties. Continuously monitoring these systems is essential to prevent unexpected shutdowns and catastrophic failures that could result in fatal accidents or significant loss in operations. However, current diagnostic engineering tools are not mature enough to detect or identify failure precursors in real time, leading to a major reliability gap in WBG-based power conversion systems. In order to reliably move WBG technologies forward, this proposal investigates: (i) WBG device degradation processes under various accelerated aging conditions and failure precursors for use in early warning systems; (ii) novel online degradation monitoring tools to improve overall reliability using readily available system components; (iii) new analytical insights for fault growth model derivation to dynamically evaluate the fault severity level, obtain an adaptive fault threshold, and predict the remaining useful lifetime; (iv) an integrated framework enabling autonomous incipient fault diagnosis and health assessment for self-monitoring smart-energy conversion systems; and (v) secondary control/modulation schemes which minimize electrical and thermal stresses on faulty WBG components for lifetime extension. These tools will provide a foundation for self-monitoring, smart-energy conversion systems that can recognize failure precursors at an early stage and thus help prevent catastrophic failures.
