隨著電動車輛對高效率馬達需求的增加，傳統永磁同步馬達因稀土材料依賴性、高溫性能限制及成本問題而受限，電激磁同步馬達(EESM)憑藉其可調節磁場的特性成為理想替代方案。
首先建立了EESM的數學模型，為後續控制策略設計提供理論基礎，提出對於電激磁同步馬達在不同轉速區域之控制策略，針對低速時採用MTPA實現低速高轉矩特性，以及高速時的弱磁控制，且針對高速區負載變動，提出一種動態調整激磁電流與d-q軸電流的轉矩補償策略，確保馬達在不同負載條件下的最佳轉矩輸出。此外，本研究分析非接觸式激磁電路架構，探討傳統滑環與非接觸式供電之差異，並模擬旋轉變壓器之電磁耦合對馬達響應之特性。
最後將非接觸式電激磁同步馬達整體系統建立於MATLAB/Simulink中進行模擬驗證，分析馬達的動態行為與響應，並透過設計軟體JMAG/FEA匯出之馬達相關參數驗證本文所提出之數學模型，以及激磁電流控制策略。

With the increasing demand for high-efficiency motors in electric vehicles (EVs), the conventional permanent magnet synchronous motor (PMSM) faces limitations due to its reliance on rare-earth materials, poor high-temperature performance, and high cost. The electrically excited synchronous motor (EESM), with its controllable magnetic field, has emerged as a promising alternative. This thesis first establishes a comprehensive mathematical model of the EESM, providing as a theoretical foundation for subsequent control strategy development. A control strategy accommodating different speed regions is then proposed: maximum torque per ampere (MTPA) is applied at low speeds to achieve high torque, while field weakening is employed at high speeds. To further enhance high-speed performance, a torque compensation strategy is introduced for high-speed regions to dynamically adjust the excitation current and the d-q axis currents in response to load variations, ensuring optimal torque output across different operating conditions.
In addition, a contactless excitation circuit is analyzed and compared with conventional slip-ring excitation, and the cross-coupling effects of the rotary transformer is modeled to evaluate its effect on motor performance. The proposed system is validated through MATLAB/Simulink simulations, with motor parameters obtained from JMAG/FEA. Results confirm that the mathematical model accurately reflects motor behavior and that the proposed excitation current control strategy ensures stable operation and improved torque performance under varying speed and load conditions.

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