This invention discloses a nano-
silicon-based special
transformer cooling oil and its preparation method. The cooling oil comprises the following components by
mass percentage: 85%–90% modified
silicone oil
base oil, 2%–3% spherical nano-
silicon particles, 1%–5% composite
antioxidant, 0.5%–2% polyether-modified
silicone oil dispersant and stabilizer, and the balance being functional additives. This invention constructs a three-dimensional thermally conductive network using surface-modified nano-
silicon, synergistically combining composite antioxidants, low-temperature flow improvers, and anti-
cavitation additives. This allows the cooling oil to maintain high insulation performance while achieving a
thermal conductivity increase of ≥50%, good low-temperature fluidity at -80℃,
partial discharge ≤5pC,
cavitation inhibition rate ≥78%, overload capacity up to 200%, and service life extended to 40 years. This product is particularly suitable for extreme environments with altitudes ≥5000 meters and temperature differences
ranging from -80℃ to +120℃, meeting the requirements of ultra-
high voltage DC converter transformers and intelligent substations in cold regions for efficient heat dissipation and long-term stable operation.