This series of three-winding oil-immersed power transformers covers rated capacities from 31,500 kVA to 300,000 kVA, with Class 1 (Type 22), Class 2 (Type 20), and Class 3 (Type 18) energy efficiency grades. Featuring a YNyn0d11 connection group, they support both step-up and step-down applications with customizable winding capacity distributions (100/100/100%, 100/50/100%, or 100/100/50%). Designed for large-scale power transmission systems, they offer low losses, high reliability, and compliance with IEC and GB standards, ideal for power plants and high-voltage substations.