MS student Andrew Freeman with Advisor A. Stillwell

The buildup of ice on aircraft poses a significant challenge for the aviation sector.  It directly contributes to fatal accidents, compromising air travel safety and necessitating costly, inefficient, and occasionally ineffective deicing methods before and during flights.  Adjacent to the development of an electro-thermal pulse dc-dc power converter for rapid and effective deicing, this work focuses on auxiliary startup and shutdown, which are necessary for rapid and repeatable deicing.  These circuits ensure flying capacitor balancing and low switch stress by limiting capacitor slew rate during on/off transitions.  Design considerations include minimizing throughput losses and ensuring safe transitions between operating converters. Verification of the mechanisms is performed via simulation compared to results of physical testing.  Furthermore, state observation methods, including voltage and current sensing, are being implemented to ensure stable control of the converter in unstable supply or loading conditions.

Figure 19. Auxiliary Startup and Shutdown Circuit.