Estimation of High Frequency Arc Conductance in High Voltage Aircraft Systems Using a Modified Mayr Model

Higher on-board electrical power generation is a promising solution to significantly reduce greenhouse gas emissions generated by the aviation industry. With the increasing level of operating voltages to meet the electrical power generation requirements and the higher system frequencies to optimize weight, arc faults will become a serious threat to future aircraft electrical systems. Other conditions such as short electrode gap, low relative humidity and low-pressure ambient environment will introduce additional technical challenges. To provide better understanding of electric arcs at aeronautical conditions, this paper investigates high current (1-1.7 kA) arcs at high frequencies (150-1000 Hz) for a range of electrode gap lengths between 2.5 and 40 mm under pressures between 0.2 to 1 bar absolute. The arc conductance, used as a parameter for comparison of arc characteristics across arc models, is found to increase at shorter gaps, lower pressures, higher humidities and lower frequencies. A black box model is used to demonstrate comparable simulated and experimental arc waveforms below the atmospheric pressure. This modeling approach provides good estimation of high-frequency high-voltage arcing characteristics under aerospace conditions without the need to perform extensive experimental testing.