Transient protection in cables under overvoltage

Abstract

With advances in technologies and materials, there is greater growth in aeronautical technologies, with an increase in the investigation and implementation of new forms of generation, distribution, and use of electric energy on board. More-electric Aircraft (MEA) reduce the aircraft's weight, reduce maintenance costs, and provide greater reliability and performance. This increases interest in new electrical technologies, such as fuel cells, variable frequency generators, new power distribution systems, and hybrid cabin pressurization systems. In this scenario, all Electric Aircraft need to consider long conductors in some cases. When the length of these conductors becomes a significant fraction of the wavelength, the transmission line model should be treated. If the High Voltage (HV) propagation is associated with switching impulses, it can produce sparks. Under these circumstances, the signal conductor and its return path must be considered together as a transmission line. The insulation must withstand without damage to avoid partial discharges and sparks. Thus, insulation is an important part of the study of protection. In addition, when considering conductors as transmission lines, the corona effect can manifest itself between conductors and result in energy losses, interference, and distortions. Despite the difficulties in its modeling, the corona effect is significant in electromagnetic transients and must be considered in the studies.The first step in designing insulation immune to partial discharges is to prevent overvoltages from flowing through the susceptible circuit. That can accomplish by insulating the circuit or providing an alternative path for these transient signals.Thus, This project aims for the following results: develop a methodology to guarantee the protection's reliability and predict failures associated with transient impulses; conceive procedures to mitigate harmful effects on the insulation of cables. (AU)