This thesis investigates the potential of Solid-State Circuit Breakers in achieving more efficient and reliable aircraft electrification, in response to the pressing issue of climate change. The aviation sector has seen a significant increase in emissions due to the growth of air travel, making aircraft electrification a promising avenue for reducing emissions and meeting global climate goals. This research supports the development of more electric, hybrid-electric and all-electric aircraft, as well as the trend towards higher voltage direct current (HVDC) power distribution systems. The objective of this research is to compare the performance of classic and solid-state relays in HVDC microgrids on board aircraft, with a focus on identifying the most suitable relay type for a 1kV/500A Bus case scenario.