Ungrounded Aircraft Power System Protection

Abstract: Recent Studies are been made to implement the 270V DC/ Hybrid 115Vac electric Power Generating and distribution systems technology used in the small military aircrafts to domestic aircrafts. The studies are being made to design and build a high-efficiency, high-reliability, fault tolerant, low-weight, low-cost hybrid aircraft electrical system for future domestic airplanes. The system is distinguished as "Grounded" and "Un-grounded" depending upon whether the neutral point of the generator is connected to ground or not. The analysis indicate an Electrical Power generating system(EPGS) distribution system weight savings due to two wires for 270-Vdc rather than three or four wires for the typical 115V,400Hz ac system. The feeders, bus lengths, and wire sizes were chosen to be representative of what would be used in modern More Electric Aircraft (MEA). Keywords: Aircraft System, Grounding, Ungrounded System.