ELECTROLUMINESCENCE AND SPACE CHARGE MEASUREMENTS FOR THE STUDY OF PEN AGEING UNDER UV IRRADIATION

• Published in: Journal of Optoelectronics and Advanced Materials 2004-09, Vol.6 (3), p.1049-1054
• Main Authors: Petre, A, Mary, D, Marty-Dessus, D
• Format: Article
• Language: English
• ISSN: 1454-4164

UV irradiation is one of the possible sources of electrical insulator degradation. Their origin can be partial discharges, parasitic discharges (environmental) or ambient light. Our intention is to determine the degree of UV interaction, according to the material photosensitivity, on the electric properties in the bulk as well as at the surface, and on the space charges creation. The presence of space charge is now recognized as one of the causes of the electrical insulating material ageing leading to their dielectric breakdown. To highlight this phenomenon, we used a space charge measurement technique in association with the results obtained by electroluminescence in the study of PEN used in the insulation of the certain rotating machines subjected to an UV irradiation. Space charge measurements were carried out using FLIMM (Focused Laser Intensity Modulation Method). This nondestructive technique permits realization of 3D cartographies [1] and localized space charge detection in a solid dielectric. Moreover, electroluminescence (EL) measurements carried out simultaneously emphasize the irradiated zone emission level variations compared to that of unirradiated part. Photoluminescence measurements confirm that the irradiation mainly involves surface modifications of the treated samples.