在高功率密度與輕量化驅動系統的發展趨勢下，機器人關節致動器對於扭矩密度、動態響應與體積限制的要求日益提高。相較於傳統徑向磁通馬達（Radial Flux Motor），軸向磁通馬達（Axial Flux Motor）具備短軸向長度、高扭矩密度與扁平化結構等特性，適合應用於機器人關節與協作型機器人等空間受限之驅動系統。另一方面，無軛鐵分段式定子（Yokeless And Segmented Armature, YASA）結構能有效縮短磁通路徑並提升磁通利用率，因此逐漸成為高性能軸向磁通馬達的重要設計方向。
然而，傳統 YASA 定子為了形成具梯形靴部（Shoe）結構，以提升磁通集中效果與扭矩輸出，通常需進行多尺寸鋼片加工、疊片與組裝，使製程與專用模具需求增加，也增加快速原型開發與小型化機器人關節應用之製造門檻。此外，部分研究採用軟磁複合材料（Soft Magnetic Composite, SMC）或非晶合金（Amorphous Alloy, AA）作為鐵心材料，但其仍存在材料取得困難、加工不易與成本較高等限制。
本研究延續既有捲繞式電磁鋼片定子之成形概念，進一步將捲繞式電磁鋼片應用於靴部結構，提出梯形捲繞齒部與分離式捲繞靴部設計。相較於傳統梯形疊片式定子需針對不同截面尺寸之電磁鋼片進行沖壓與疊片，本研究利用連續電磁鋼帶進行捲繞成形，可減少多尺寸疊片與專用模具之需求，並提升原型製作與設計變更之彈性。同時，藉由電磁鋼片之薄片化與片間絕緣特性，改善碳鋼靴部於高速交變磁場下之渦流損耗問題。
為驗證捲繞式齒靴定子結構之可行性，本研究以8極9槽（8p9s）雙轉子單定子軸向磁通馬達為基礎，透過三維有限元素分析（3D Finite Element Analysis, 3D FEA）比較捲繞式有靴部定子、傳統疊片式有靴部定子及無靴部定子於磁交鏈、反電動勢與頓轉扭矩（Cogging Torque）等電磁性能之差異，並進一步比較捲繞式電磁鋼片靴部與碳鋼靴部於高速運轉下之渦流損耗。此外，本研究考量實際捲繞製程限制，設計梯形捲繞齒部與分離式捲繞靴部，並完成定子模組及整體馬達原型之製作與性能測試，以驗證其實際製造與運轉可行性。
研究結果顯示，相較於無靴部結構，捲繞式齒靴定子之頓轉扭矩降低約 17.4 %，磁交鏈提升約11.2 %，平均輸出扭矩提升約8.8 %，扭矩漣波則由 4.8 %降低至3.3 %，降低1.5個百分點。而與傳統疊片式有靴部定子相比，兩者之平均扭矩與磁交鏈差異分別約為1.0 %與1.4 %，Model A之頓轉扭矩則較Model B高約 6.1 %，顯示兩者主要電磁性能仍維持相近。另一方面，於4000 rpm、電氣頻率266.7 Hz之空載條件下，捲繞式電磁鋼片結構之渦流損耗較碳鋼靴部降低約99.3 %。實體製作方面，本研究已完成梯形捲繞齒部、分離式捲繞靴部、定子模組與整體馬達之組裝，並於動力計測試中達到約0.4 Nm之輸出扭矩及約194.7 W之輸出功率，證實捲繞式電磁鋼片應用於靴部結構具有實際製造與運轉之可行性。

This study investigates the application of a wound electrical-steel tooth-shoe structure to an axial-flux permanent-magnet motor intended for robot-joint actuation. A double-rotor single-stator, 8-pole/9-slot configuration with ferrite permanent magnets was designed, and a trapezoidal wound tooth together with a separately wound shoe was developed to improve manufacturability while retaining the electromagnetic function of the shoe. Three-dimensional finite element analysis was used to compare wound and conventional laminated stators, stators with and without shoes, and wound electrical-steel shoes with carbon-steel shoes. Compared with the no-shoe stator, the proposed wound tooth-shoe stator reduced cogging torque by 17.4%, increased flux linkage by 11.2%, increased average torque by 8.8%, and reduced torque ripple from 4.8% to 3.3%. Compared with the conventional laminated tooth-shoe stator, the differences in average torque and flux linkage were approximately 1.0% and 1.4%, respectively, while the cogging torque of the wound design was approximately 6.1% higher and its torque ripple was 0.2 percentage points lower. At 4000 rpm, corresponding to an electrical frequency of 266.7 Hz, the eddy-current loss of the wound electrical-steel structure was 0.755 W, 99.3 % lower than that of the carbon-steel shoe. A prototype was fabricated and tested, achieving approximately 0.4 Nm torque and a maximum mechanical output power of 194.7 W. These results demonstrate the manufacturing and operating feasibility of applying wound electrical steel to a separated shoe structure for axial-flux motors.

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