Zero-occupancy three-phase oil-immersed underground transformer is a type of compact distribution power equipment designed for underground installation, featuring fully sealed oil-immersed construction, three-phase power conversion, and maintenance-free unattended operation. It is engineered to be installed directly below ground level or in underground pits, providing power distribution solutions for urban areas and space-constrained environments without occupying surface land.
Key Design Features
- Adopts high-grade sealing technology to effectively isolate underground moisture and corrosive media
- Protection rating up to IP68, capable of continuous operation when fully submerged in water
- Eliminates the need for a separate oil conservator tank; corrugated-fin radiators compensate for oil volume changes through elastic expansion and contraction
- Vacuum oil impregnation removes air bubbles from windings for stable insulation performance
- No routine oil level checks, filter replacements, or on-site inspections required
- Sealed design extends service life and eliminates regular maintenance intervals
- Can be equipped with remote monitoring sensors for temperature, load, and power factor tracking
- Built-in protective devices (fuses, load switches) provide autonomous fault protection