Investigation of Radiated EMI Evolution of High-power Density GaN-based Converter Under Short-circuit Accelerated Aging
Résumé
Gallium Nitride (GaN) transistors have garnered considerable attention in power electronics owing to their superior efficiency. Nonetheless, enduring reliability issues remain, particularly under intense operational situations. This research examines the progression of radiated electromagnetic interference (EMI) in a high-power density GaN-based converter undergoing short-circuit accelerated aging. The experimental configuration simulates real-world stresses by subjecting the converter to repeated short-circuit occurrences to evaluate the degradation of essential electrical properties. A considerable spike in near-field EMI emissions was detected, corresponding with the evolution of parasitic capacitances. The findings indicate a reduction in gate-drain capacitance (CGD), resulting in increased dv/dt, which exacerbated high-frequency harmonics and electromagnetic interference (EMI) emissions. Concurrently, gate-source capacitance (CGS) demonstrated an increase, affecting gate drive stability and switching dynamics. Likewise, reverse transfer capacitance (CRSS) decreased, hence expediting switching transitions and augmenting EMI.
