Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Résumé

Mineral-based insulating liquids have been crucial in the power sector as coolants and insulators for several years. However, environmental concerns surrounding these liquids have prompted a search for alternatives. Plant-based liquids are now emerging as promising options for transformer insulation due to their eco-friendly nature and minimal contribution to exacerbating global warming. Yet, some properties of plant-based insulating liquids lag behind mineral oil, notably in viscosity, oxidation stability, and pour point. This study explores a blend of canola oil and methyl ester from palm kernel oil to achieve an oil blend with reduced viscosity and improved oxidation stability. ASTM D 2440 guided the selection process through oxidative investigative analyses, considering factors like acidity, viscosity, FTIR, and dielectric spectroscopy. The sample combining equal parts canola oil and methyl ester exhibited superior oxidation stability. Moreover, to enhance the chosen blend's crystallization temperature, Taguchi-Grey relational analysis was used with Viscoplex 10–312 and Viscoplex 10–171 pour point depressants. The optimal performance, derived from Grey relational grading, was achieved when 0.7 wt% of both depressants was added to the base liquid. This synthesized liquid, comprising 50% canola oil, 50% methyl ester from palm kernel oil, and 0.7 wt% of both depressants, presents itself as a more effective green alternative insulating liquid in the industry, reducing the environmental impact caused by mineral oil.