Semi-analytical calculation method for parasitic capacitance of high-frequency transformers based on partitioned solution

The parasitic capacitance of the windings significantly affects the transmission characteristics of high-frequency transformers, and its accurate calculation is crucial for the optimal design of transformers. To address the limitations of traditional methods, which exhibit low computational efficiency and difficulty in accurately accounting for winding-to-ground capacitance, this paper systematically examines the influencing factors and solution principles of various types of parasitic capacitances in high-frequency transformers. We propose a semi-analytic calculation method based on the partition solution strategy. For inter-winding parasitic capacitance, we derive analytical expressions for different winding configurations. For winding-to-ground capacitance, we establish three-dimensional finite element models of high-frequency transformers with diverse structures and dimensions to enable parameter fitting and solution. The accuracy of the proposed method is validated through comparison with experimental results.