Partial Discharges under Slow Impulse Voltage Stress

Abstract:
The interpretation of the partial discharge measurement results under DC voltage stress requires understanding of the relevant physical phenomena. In this paper it is shown that the charge accumulation at the interface between the gaseous and the solid dielectrics is the key mechanism influencing the discharge activity. To demonstrate this mechanism the specimen are stressed with a slow impulse voltage. Partial discharge measurements on different specimen with artificial defects (internal and external partial discharges) are provided.