The American-style combined transformer is an integrated outdoor power transformation device that combines an oil-immersed transformer (containing high-voltage load switch fuses), low-voltage switchgear, monitoring and control systems, UPS backup power, control transformers, measurement and protection components, and indicating instruments within a high-protection-level enclosure. The high-voltage load switch fuses are installed inside the oil tank, and the transformer uses cooling fins for heat dissipation. It features compact size, safety, reliability, high integration, energy efficiency, environmental friendliness, intelligent monitoring and management, and flexible configuration. It is suitable for small to medium-capacity applications such as photovoltaic power generation and wind power generation. Commonly used transformer capacities for 35kV and below include 1600kVA, 2000kVA, 2500kVA, 3150kVA, and 4000kVA.