Stability Enhancement of High Frequency DC Distribution Network by Incorporating Wide Bandgap β-Ga2O3 Power MOSFET as Switching Element

摘要

We propose stability enhancement of a high frequency (1.2MHz) DC distribution network comprising numerous feedback-controlled buck converters by replacing their conventional electro-mechanical switches with ß-polymorphic Gallium Oxide (β-Ga₂O₃) power MOSFETs operated on soft switching. The performance anomaly in terms of output voltage oscillations and poor overall stability resulting from negative incremental impedances have been successfully addressed with the help of the Middlebrook Criterion. Having the highest Johnson's Figure of Merit (2844) among all studied Wide Band Gap (WBG) materials, β-Ga₂O₃ promises the best Power-Frequency operation. In our simulations here, it leads to substantial performance improvement compared to the conventional system design - in terms of output voltage oscillation and overall stability of the DCdistribution network. Losses have been calculated and analyzed, with regard to the Minimum System Efficiency Degradation versus Maximum Stability Enhancement trade-off. Further, we demonstrate the dominance of a solid-state switch at the converter input, over a feedback loop at the back-end, in securing a system with higher stability.