Electric Field and Current Conduction Modelling in Bi-layers Insulations HVDC Aeronautic Cables

For decades, electrical energy network in aircrafts was based on relatively low voltage (mainly 115V ac and 28V dc), providing the power to the different energy functions of the aircraft. Great strides have been made in the new aircraft generations, notably the A380 and the Boeing 787, with an increase of the aircraft size, and with the input of electrical energy in replacement of certain hydraulic or pneumatic actuations. Today, there is a tendency to replace HVAC network with HVDC (+/-270V dc, 540 V dc and higher in the future) network in order to benefit from these many advantages. This increase of the electrical energy pushes the transmission cables to their limits and leads to questions about the impact of these new constraints on the aeronautic cables insulation. This article presents a macroscopic model and comparison between simulation results and measurements made on bi-layer materials used in actual aeronautic cable insulation. The electric field distribution within materials and kinetic of interfacial charges build-up are analyzed.