隨著人們對高功率密度的要求不斷提高以及環保意識增長，永磁電機(PM Machine)最近已被用於多種工業應用，包括機器人、風力渦輪機、航空航太和電動車 (EV)。由於傳統電機模型中為了方便計算，假設中簡化了鐵芯損失與齒槽轉矩等因素，然而在啟動及低速運轉時，齒槽轉矩影響速度表現；在工作在高速和高頻下，導致高功率損耗和溫升，正確考慮功率損失在建模至關重要。
本文將針對兩款永磁電機-永磁游標電機與永磁同步電機進行鐵損與齒槽轉矩探討，引入無載有限元素方法(FEM)搭配數據分析進行建模，在鐵損模型中採用曲線擬合(Curve-Fitting)等效鐵損電阻；而在齒槽轉矩建模中採用傅立葉轉換(FFT)數據進行建模。為了符合使電機模擬通用性，更將電機模型結合雙埠網路架構(Two Port Network)建立在模型在環(MIL)中。
建立之電機模型可顯示電機各項特性，如:磁性電機齒輪比、鐵損、齒槽轉矩等；並且透過鐵損實測證實所提出鐵損建模之準確性。綜合來說，透過此建模架構可使永磁電機模擬環境開發更為便利且精準。

With increasing demands for high power density electric motor and the growing environmental awareness on climate changes, permanent magnet motors have become a sort of electric machine across various industrial applications, including robotics, wind turbines, aerospace, and electric vehicles (EVs). To facilitate calculations in the traditional motor model, factors such as core loss and cogging torque are simplified as assumptions. However, during startup and low-speed operation, cogging torque affects the speed performance of electric machines; likewise, when operating at high speed and high frequency lead to more loss and temperature rise in the electric machine. It is crucial to correctly consider power loss due to core loss and cogging torque in electric machine modeling.
This article will discuss the core loss and cogging torque of two permanent magnet motors - Permanent Magnet Vernier Machine and Permanent Magnet Synchronous Machine. The finite element method (FEM) and data analysis will be employed for modeling. In the core loss model, Curve-Fitting equivalent iron loss resistance is used; while in cogging torque modeling, Fourier transform (FFT) is used for the modeling. Two Port Network framework is used to improve visualization and better understanding of the motor model developed for the model-in-the-loop (MIL) simulation.
The motor modelling using Two Port Network framework provides clarity by showing various characteristics of the motor, such as iron loss, cogging torque, magnetic gear effect etc. The accuracy of the proposed core loss modeling is verified through no load test of the electric machine. In summary, this modeling framework makes the development of permanent magnet motor simulation environment more convenient and accurate.

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