本研究主要在於設計一直驅式筒狀線型往復式壓縮機，以取代傳統採用旋轉馬達配合連桿機構帶動活塞之驅動方式，如此可降低活塞所造成的側向力，減少摩擦損耗，進一步達到高機械強度、低機械損耗、低噪音及高效率之目的，並藉由輕量化動子設計以提高工作頻率。該線型馬達應用於小型壓縮機上有結構簡易、加工組裝精密度要求低以及成本低等優點。往復式壓縮機需要較大的馬達推力來達成氣體的壓縮循環，然而受限於壓縮機整體體積，一般筒狀型線型馬達無法滿足需求，故本研究利用軟磁複合材料(Soft Magnetic Composite, SMC)之特色設計一具三維磁場之筒狀線型馬達，藉此提升槽面積以允許較多的繞線匝數，在有限體積下，使馬達可達到較高的推力密度。
由於本型馬達具有特殊之磁路結構，因此需利用三維有限元素軟體來建模求解。然而三維模擬計算在分析上十分耗時，為了縮短設計時程，本文提出一氣隙磁導分佈模型結合等效磁路分析方法，使得在馬達設計初期，即可快速預測馬達輸出特性，如頓轉力(Cogging Force)與勞倫茲力(Lorentz Force)，提供定性與定量上的參考。如此可大幅降低設計流程所需的時間。本研究最後利用有限元素軟體模擬比較馬達輸出特性，以驗證所提出分析方法的合理性與正確性。

This thesis proposes a tubular linear motor for direct driving reciprocating compressors to replace the common-use configuration of rotary motors with crank. This design can hence reduce the cylinder wearing problem caused by the crank side force. It can also achieve the objective of high mechanical strength, low mechanical loss, low noise and high efficiency. A light mover mass is employed to increase the operating frequency. The proposed design has the advantages of simple structure, low demand of manufactures and low cost. Reciprocating compressors often require large thrust to drive and complete coolant compression cycles. However, the motor specification is limited by the volume of the compressor and it is often beyond the capability of common tubular linear motors. In order to solve this problem, this thesis designs a single-phase tubular linear motor formed with soft magnetic composite (SMC). Such a 3-D stator design allows large slot area for more conductors so that the slot-fill factor can be greatly increased. Therefore, the trust density can be increased for direct drive of the reciprocating compressors.
Since this motor has a complex flux distribution, the time-consuming 3-D finite element analysis is required to perform the simulation. In order to simplify the design process, a model of air-gap permeance is developed to work with magnetic circuit modeling so that the characteristics such as cogging force and electromagnetic thrust can be calculated at the primary stage of motor design. This will improve the design efficiency. The analytic results are compared with the finite element simulation, and the constructed model is verified.

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