Oil-immersed transformer

Oil-immersed transformers are widely used in power transmission and distribution systems. They employ insulating oil as both a cooling and insulating medium, with a core assembly comprising an iron core, windings, an oil tank, insulating oil, and auxiliary components such as radiators and bushings. During operation, heat generated by winding losses and core losses is conducted through the insulating oil to the tank walls and then dissipated via the radiators, thereby achieving effective cooling. Simultaneously, the insulating oil isolates the windings from the ambient air, enhancing insulation performance. With low no-load and load losses, excellent resistance to lightning surges, strong short-circuit withstand capability, and significant energy-saving benefits, these transformers represent an ideal choice for the ongoing national grid modernization projects.

Dry-type transformer

A dry-type transformer is a power transmission and transformation device that uses air or a gas such as nitrogen as its cooling medium, eliminating the need for insulating oil. Its core components include an iron core and windings insulated by epoxy resin casting or impregnation, complemented by auxiliary devices like temperature controllers and cooling fans. The windings are encased in insulating materials and dissipate heat primarily through natural air convection (or with forced cooling via fans), thereby avoiding the risks of oil leakage and fire associated with oil‑immersed transformers. Additionally, dry‑type transformers are more compact, easier to maintain, energy‑efficient, environmentally friendly, maintenance‑free, offer superior fire‑resistance, produce no pollution, and are simple to install.