Breakdown Characteristics of C60 Modified Transformer Oil

Transformer mineral oil play important roles in the insulating system of the transformer, such as heat dissipation and electrical insulation. C60 is an ideal choice for mineral oil modification due to its good lubricity and oil solubility. In this work, we attempted to obtain C 60 nano-mineral oil with concentrations of 50 mg/L, 100 mg/L, 150 mg/L, 200 mg/L,250 mg/L and 300 mg/L respectively. Ultrasonic dispersion were conducted when preparing the nanofluids. We determined the electrical properties of nano-modified oil samples with different concentration, (including negative and positive lightning impulse breakdown voltage and AC breakdown voltage). The results illustrate that the positive lightning impulse breakdown voltage increased by 7.51% and the negative lightning impulse breakdown voltage increased by 8.33% compared with the fresh oil sample at the concentration of 150 mg/L. At the concentration of 200 mg/L, the negative lightning impulse breakdown voltage increased by 9.30% while the AC breakdown voltage peaked at this concentration, increased by 18.02%.