Tunnel transformers are special transformers designed for underground tunnels and subway projects. It is waterproof, dustproof and moisture-proof, adapting to special use environments. In addition, tunnel transformers usually have fire resistance and earthquake resistance to ensure reliable operation and safety in special environments. The design considers heat dissipation and ventilation to ensure normal operation in underground enclosed spaces. Compact design adapts to limited spaces and meets underground engineering needs. Tunnel transformers play an important role in subway and tunnel projects to ensure safe and reliable operation of the power supply system.