Arc Model and Analysis in the New Generation More Electric Aircraft

Abstract

The idea of achieving zero CO2 emissions in the transport sector is a key concern to many global organisations operating in this sector. Efforts in this regard could be best described as being in the transitional stage, particularly in the aviation sector, which is gradually seeing the introduction of a more advanced generation of machines and consumption equipment to accommodate the new era of aircraft (such as the More Electric Aircraft (MEA)), which in turn has seen a resulting increase in greater current and voltage consumption. As a consequence, arcing between electrodes (Arc Tracking) might occur more frequently since the higher input voltages in the new modern aircraft are relatively close to the space breakdown voltages between electrodes; an area which may lead to aircraft being damaged. Therefore, this report aims to analyse arc behaviour based on an arc sustainability investigation, in addition to discussing arc behaviour through three perspectives which include V-I characteristics, arc conductance and power cooling in order to discover a method that may assist in minimising the higher frequency of arcing in the MEA. The results in this study indicated that an enhanced operating frequency resulted in the minimising of arc conductance, which prevented the arc forming between the electrodes for prolonged periods. Furthermore, arc time constant was considered as a trade-off parameter, with a significant contribution on power losses growth being offset with a higher reduction in arc voltage once sustained for a lengthy period. This raises questions as to the efficacy of this parameter in diminishing arc behaviour. Furthermore, it was noted that if the arc occurred between electrodes, arc time constant could not be controlled. In contrast, where this arc occurred between contact with the circuit breakers, it could be minimised through choosing an appropriate material such as copper or carbon. This procedure was conducted through a simulation in MATLAB using Black box models, which included the Cassie, Mayr and Schwarz models respectively. Electron behaviour was clarified from four perspectives: (1) ignition, relaxation and extinguish procedure, (2) gaining and releasing energy methodology, (3) pressure and temperature effectiveness on arc initiation, and; (4) collision rate speed variation with both power losses and changes in arc conductance.