Space Charge Measurement by PEA Method on an Aeronautical Cable

Technological evolutions in aircraft networks let us foresee an increase of the DC voltage up to several kilovolts while keeping minimal insulation thickness. This trend results in a strong increase of the electric field in the insulations and space charge can become an issue for the reliability of the systems. Indeed, space charge accumulation modifies the electric field distribution and may lead to a premature aging of the dielectric. Besides, the field distribution in complex structures such as multilayers cannot be anticipated under DC as easily as under AC because conductivity is more difficult to estimate and varies much more than permittivity. In this paper, we present the first results obtained on aeronautical cables. For this, it was necessary to develop a deconvolution strategy adapted to aeronautical cables to obtain electric field and charge density profiles in a part of the insulation thickness.