This project involves the design of a cost-optimized three-phase YD distribution transformer with specific performance and design constraints. Our goal is to deliver a transformer with nominal primary to secondary line to line voltages of 10kV/400V and a nominal apparent power of 1100kVA, ensuring efficiency levels above specified thresholds at different load conditions. The design addresses the short circuit current limitations imposed by existing circuit breaker ratings and considers both air and oil cooling methods with detailed constraints on materials, geometrical dimensions, and raw material costs.

1. High Efficiency:

   • 85% efficiency at 50% load,

   • 95% efficiency at 75% load,

   • 92% efficiency at full load, all at unity power factor and rated voltage.

2. Design Constraints

   • The project details constraints related to cooling methods, winding current densities, core and winding materials, insulation capabilities, and geometrical considerations.

3. Cost Considerations

   • Includes a detailed breakdown of raw material costs for copper, aluminum, silicon steel laminations, transformer oil, and structural steel.

The design process is iterative, encouraging the use of computational tools for design and analysis. Key steps include initial dimensioning, selection of design variables, electromagnetic analysis, performance parameter analysis, and sensitivity analysis. The process aims at optimizing the design for cost while meeting all operational specifications.