dc.title: Compact pulsed power systems using GaN devices dc.description.abstract: Pulsed power systems enable the delivery of extremely high power over ns-to-μs timescales, with fast rise times, high voltages, and large currents. Applications range from military systems, such as rail guns and directed energy weapons, to civilian uses, including high-energy lasers, plasma generation, and tumor ablation. Traditional pulsed power generators rely on spark gap switches, which are hard to control and expensive. Modern approaches leverage modular architectures, such as inductive voltage adders (IVAs), and advanced semiconductor devices, including SiC switches, to achieve scalable, controllable, and fast pulses. This dissertation investigates the limitations and opportunities in synthesizing an IVA, a compact pulsed power system, using modern GaN high electron mobility transistors (HEMTs).
Key contributions of the dissertation include: a dynamic Ron measurement method for GaN devices in sub-μs pulsed conditions, including characterized data for commercial GaN devices; a comparative evaluation of ultra-fast gate-driver topologies for optimal rise-time performance; the development of a closed-loop synchronization scheme to align gate signals across bricks with sub-ns precision; an exploration of non-conventional magnetic geometries for the IVA conductors; and finally, the design and demonstration of a GaN-based IVA achieving a 4.96-ns rise time at 2 kV and 32 A.
The findings provide design strategies for optimizing device selection, minimizing parasitic effects, and improving pulse rise times in high-voltage, modular pulsed power systems – advancing the integration of GaN devices into next-generation high-speed pulse generators.