Interest of nonlinear ZnO/silicone composite materials in cable termination

A common problematic in High Voltage (HV) and Medium Voltage (MV) applications is the presence of local triple points. A triple point is the junction between three media characterized by a specific permittivity; for instance: air (relative permittivity ≈ 1), a conductor and a dielectric (relative permittivity > 1). In this location, the control of the electric field is essential in order to minimize the risk of partial discharge (corona effect) or surface electrical discharges. In addition, surges (transient overvoltage imposed by lightning and switching operations) may lead to premature degradation of the dielectric material.