本文著重於分析永磁同步馬達轉子磁障層設計與抗退磁能力之關係。在馬達初步設計時，較高的磁鐵操作點有利於增加馬達的過載能力，提高馬達最大功率密度，而車用動力馬達經常運作於高溫與高電流密度之操作環境，容易使磁鐵發生不可逆的退磁現象，進而導致馬達壽命減短。為避免此狀況發生，除了改善散熱條件外，藉由磁路設計提高馬達抗退磁能力也相當重要。
本文分為兩部分，第一部分為轉子幾何改變對於特徵電流與抗退磁能力之影響；第二部分則藉由加入磁障層設計，在維持馬達性能條件下提高磁鐵抗退磁能力，並以有限元素分析模擬驗證磁鐵退磁面積與部分退磁現象。最後，本文提 出V型內藏型永磁同步馬達設計流程，透過模擬與實驗量測，驗證磁障層設計對於抗退磁能力的重要性。

This thesis focuses on the analysis and design of flux barriers for improving the anti-demagnetization capability of interior permanent magnet synchronous motor (IPMSM).
The finite element analysis (FEA) is applied in order to understand the flux barrier impact on the IPMSM anti-demagnetization capability. It is necessary to improve the anti-demagnetization capability of the traction motors that usually operate at high temperature and high current density. This makes the permanent magnet motor vulnerable to irreversible demagnetization.
In this thesis, a brief study of the characteristic current and the demagnetization characteristic of the IPMSM is conducted to understand their relationship on the motor performance during flux weakening operation. The study is done by varying the rotor geometric variables and observing their effect on the parameters (characteristic current and demagnetization characteristic), which are calculated by FEA.
Finally, various V-type IPMSMs are designed. The best model of anti-demagnetization capability is selected as the prototype design. The design is verified by experiments.

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