# A Novel Magnetic Equivalent Circuit Model for the Corner of Inductor Core  
[PERSON]  
1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) [PERSON]  
1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) [PERSON]  
1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) 1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 4000714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) 1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) 1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 4000714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) 1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) 1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.C. ); [EMAIL_ADDRESS] (L.D.) 1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Bebei District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.C.); [EMAIL_ADDRESS] (L.D.) 1 Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Beivelt District, Chongqing 400714, China; [EMAIL_ADDRESS] (X.W. ); [EMAIL_ADDRESS] (H.  
element method [12], the common method is to simplify the corner as a quarter-circle that has a fixed radius, replacing the original rectangular geometry, such as the IEC (International Electrotechnical Commission) 60205 [13] model, which has a radius equal to half the average length of the corners and is adopted in [9]. In the Snelling [14; 15] model, the authors choose a quarter of the average length of the corner as the radius and this corner model is adopted in [5; 6]. In the [PERSON] [16] model, the corner flux path length is equal to half the rectangular side beside the limb and is adopted in [11]. However, these corner models use a single fixed flux path length to calculate the reluctance without considering the nonlinearity of reluctance. In real cases, the corner flux density distribution is non-uniform where the inner corner is high, and the outer corner flux density is low [17]. The magnetic flux mainly flows around the inner corner. As the strength of the magnetic field increases, the inner corner reaches saturation and leads to a significant increase in local reluctance and the flux density (\(\mathbf{B}\)) distribution also changes. Therefore, the simplified reluctance equivalent length model of the corner is not consistent with the real condition and contributes to inductance error, especially under the saturation condition. In this paper, we focus on the power inductor, especially with UI/EI or other core structures with rectangular corners. In order to describe the flux density distribution at the corner and improve the accuracy of the core corner reluctance, so as to improve the accuracy of inductance calculation, we propose a local MEC model of a corner. Based on the finite element analysis, the corner and the joint part between the corner and the core limb enclosed by winding are divided into several reluctance branches to describe the flux density distribution.