A General Analytical Model of Single-Layer Common-Mode Chokes

To accurately model common-mode (CM) chokes is crucial for ensuring the design and optimization of EMI filters. This letter identifies the limitations of the commonly employed analytical model, which results in significant margin errors when applied to CM chokes. It proposes a comprehensive and more precise analytical model that addresses these errors by considering the influence of time-varying electromagnetic fields and the geometric characteristics of CM chokes. Furthermore, this letter provides a detailed explanation of the physical significance behind the proposed model. Both methods are compared, and the suggested approach is validated through simulations and experiments in four distinct scenarios.