Electrical stress enhancement of contaminants in XLPE insulation as quality control criteria

Cleanliness is one of the most important quality criteria for high performance XLPE insulation materials. The cleanliness level that is routinely achievable today forms the foundation for development of smaller cable constructions and the continued development of 500 kV XLPE cable system. The cleanliness specifications for these compounds need to consider the typical geometry and electrical nature of any contaminant. A combination of quality control techniques makes it possible to identify frequency, type and geometry of contaminants. By applying theoretical models, calculation of electrical stress enhancement from these contaminants can be assessed with improved reliability.