本論文旨在研究將捲式鐵心配電變壓器之鐵心做尺寸改良及修改設計結構，並使用電磁模擬軟體之有限元素法來達到降低整體變壓器的鐵心損失及提高運轉效率為目標。且研究捲式鐵心對於配電變壓器的磁場及電氣特性的影響，並針對於捲式鐵心的磁路特性、電壓及電流轉換特性、鐵心損失、激磁電流、運轉效率、負載、輸入電源及頻率等不同的影響來做更深入分析，首先經由現場實測捲式鐵心變壓器之電氣特性的結果來建立有限元素模型，接著將配電變壓器之捲式鐵心尺寸及型式做重新分析及設計，最後將所改良的結構與基本型捲式鐵心之特性做比較，俾選擇最佳捲式鐵心的結構得到高品質、低鐵損、高效率之捲式鐵心配電變壓器，並瞭解在任何有可能對於捲式鐵心配電變壓器在各種干擾及影響下的電氣特性。

The aim of this thesis is to modify the size and structure of roll-iron core distribution transformers to achieve lower core loss and higher operating efficiency using an electromagnetic-field simulation software based on finite-element method (FEM). To study the influence of various dimensions and structures of roll-iron core on magnetic-field characteristics of the distribution transformers, magnetic-field distribution, voltage-current transformation characteristics, core loss, exciting current, operating efficiency under different loading effects and various values of input voltage and frequency are examined. The first step is to validate the proposed FEM model by comparing the measured electrical quantities of a roll-iron core distribution transformer to the simulated ones. After the FEM model has been established, the original size and structure of the roll-iron core can be modified and redesigned. The performance of the revised dimensions and structures is compared with the one of basic roll-iron core model in order to obtain the best structure and dimension for the studied roll-iron core distribution transformers with high quality, low core loss, and high efficiency. In addition, the characteristics of the studied roll-iron core distribution transformers under various disturbance conditions are also investigated.

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