當前電力電子領域追求轉換器具有高功率密度以及體積小型化，因此提高操作頻率以實現小型化為現今的設計趨勢。本論文旨在探討平板變壓器在高頻操作時的特性，因此設計三種不同排列的繞組，並使用S參數來獲得變壓器的頻率響應與物理特性。研究中採用自適應建模法和預設等效電路建模法，分別建立不同的變壓器等效模型。自適應建模法根據實際測量數據動態調整模型參數，提高模型的準確性和可靠性，但是計算過程較為複雜，計算出來的等效變壓器電路非常龐大，且物理意義不直觀。預設等效電路建模法則是基於既有理論和經驗建立模型，物理意義明確但是模型階數較低，在高頻的部分，無法完全符合實際的情況。本論文基於提出之兩種建模法分析不同繞組排列的平板變壓器。並採用返馳式轉換器作為實驗平台，將變壓器等效模型導入電路模型中，用以驗證等效電路與實際電路的特性是否相符。最終實驗結果顯示，本論文所建立之變壓器等效模型在返馳式轉換器中具有與實際電路相符的頻率響應以及動態特性，證實等效模型具有準確性和有效性。

In power electronics, there is a pursuit for high power density and miniaturized volume, making high-frequency operation a design trend. This thesis investigates the characteristics of planar transformers under high-frequency conditions, designing three different winding configura-tions and using scattering parameters to obtain the transformer's frequency response and physical characteristics. The study uses adaptive modeling and predefined equivalent circuit modeling methods to establish different transformer models. The adaptive modeling method dynamically adjusts model parameters based on actual measurement data, improving accuracy and reliability but resulting in complex and less intuitive circuits. The predefined equivalent circuit modeling method, based on existing theories and experience, provides clear physical significance but has a lower model order that may not fully conform to high-frequency conditions. This thesis analyzes planar transformers with different winding configurations using these modeling methods and employs a flyback converter as the experi-mental platform. The final results show that the transformer equivalent model has frequency response and dynamic characteristics in the flyback converter that align with the actual circuit, confirming the model's accuracy and validity.

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