Improved IGSE Core Loss Calculation Method Based on The Magnetic Density Distribution Characteristics of Large-Size Cores

Accurate calculation of transformer core losses is an important basis for transformer loss analysis and optimal design. The Improved Generalized Steinmetz Equation (IGSE) is a non-sinusoidal excitation core loss calculation method based on the assumption of magnetic density consistency, which is widely used for core loss calculation of small-capacity high-frequency transformers. However, for megawatt-class medium-frequency transformers, the core size is significantly larger than that of small-capacity high-frequency transformers, and the magnetic density distribution on the core cross section is severely uneven, leading to a significant increase in the error of the iron loss calculation by the traditional IGSE equation. In this paper, the uneven magnetic density distribution of the medium frequency large size silicon steel core is analyzed in the original sense. The IGSE algorithm is modified by core stratification and loss integration methods. The accuracy of the modified IGSE algorithm in large-size core loss calculation is significantly improved, and the error is less than 10%, which is an important guidance for core loss optimization.