Compared with non-grain-oriented silicon sheet (NGO), the grain-oriented silicon sheet (GO) has superior magnetic characteristic along its rolling direction, but bad
characteristic along other directions. GO silicon sheet is a popular material used in transformers 1. For electrical machines, it can be only used to design the stator teeth 2. While,
reasonable design and optimization of joint part between the GO silicon sheets and NGO silicon sheets is very important, otherwise the main performance of electrical machine with hybrid
GO - NGO cores will be reduced. In the pasts, optimizing main dimensions is a main mainstream however shape optimization of the joint part was neglected. In this paper, the shape design
optimization method is adopted for obtaining the best joint shape between the GO and NGO silicon sheets based on an 12 slot 8 pole (12s8p) interior permanent magnet machine (IPMSM)
as shown in Fig. 1(a). For achieving better machine performance, the magnetic barrier shape are optimized as well. Specifically, the GO silicon sheets are used for building the stator teeth,
and the others are made by NGO silicon sheets. By using finite element method (FEM), the main performance of the IPMSM with different GO silicon sheets can be obtained. Piecewise
linear interpolation method is used to establish the GO silicon sheets and rotor barrier shape, as shown in Fig. 1(b) and (c). Fig. 1(d) shows the obtained new rotor barrier shape after
optimization. For benchmark comparison the optimized traditional IPMSM with 12s8p and IPMSM with 48s8p with NGO silicon sheets are adopted. Fig 2 shows the performance
comparison of 12s8p IPMSM using NGO (NGO-IPMSM (12 Slot)), 12s8p IPMSM using GO teeth (GO-IPMSM (12 Slot)), 12s8p IPMSM using GO teeth and new magnetic flux barriers
(GO-B-IPMSM (12 Slot)), and 48s8p IPMSM using NGO (NGO-IPMSM (48 Slot)). More results will be presented in the final submission.
1 S. Magdaleno-Adame, T. D. Kefalas, A. Fakhravar and J. C. Olivares-Galvan, "Comparative Study of Grain Oriented and Non–Oriented Electrical Steels in Magnetic
Shunts of Power Transformers," 2018 IEEE International Autumn Meeting on Power, Electronics and Computing (ROPEC), 2018, pp. 1-7.
2 Y. Tsuchiya and K. Akatsu, "A Study of the Switched Reluctance Motor using Grain-Oriented Electrical Steel Sheets," 2020 IEEE Energy Conversion Congress and Exposition (ECCE), 2020, pp. 3623-3628.