Electrical Characterization and Modeling of High Frequency Arcs for Higher Voltage Aerospace Systems

Abstract

Arcing in future high-voltage aerospace systems could occur more frequently and cause irreversible damage to electrical components and system structure, and increase the risk of fire. While arcs seen in low-voltage aerospace systems tend to be long-duration and low-energy events, higher-power but short-duration arcs may occur in high-voltage aerospace systems if they are readily detectable by system protection. This article investigates the characteristics of high current arc faults generated at the ac frequencies expected in future rotating machines used for higher voltage aerospace systems. As such, arcs with a peak current up to 4.6 kA are generated at frequencies in the range of 0.5-2 kHz using an underdamped RLC circuit, under pressures of 0.2-1 bar absolute. High-frequency arcs exhibit a similar characteristic to lower-frequency arcs. A reduction in pressure results in lower arc voltage and arc power. Arcing tests at atmospheric pressure may therefore represent a worst-case scenario and the development of a low-pressure test environment may not be necessary. A black box model is developed to provide good agreement with experimental arc voltage waveforms for different parameters investigated in this study. This is a generalized modeling approach to estimate high-frequency high-voltage arcing characteristics without recourse to experiment.