Investigation of the Partial Discharge Inception and Flashover with IEC-based CTI Electrodes at Varying Pressures for Aerospace Applications

The surface discharge phenomenon of solid insulating materials is crucial for designing aeronautical electrical equipment. The comparative tracking index (CTI) is a mandatory step for designing the creepage distance and the choice of the insulating material. Following the testing procedure defined in the IEC standards, the materials are classified into different groups. On the other hand, the stage before the apparition of a partial tracking arc is characterized by partial discharge inception. This paper deals with the measurements of partial discharge inception voltage (PDIV) and flashover voltage (FOV) by using CTI electrodes at varying atmospheric air pressures with dry and clean solid insulating materials. The goal is to quantify and qualify the behavior of the materials before performing CTI tests.