A permanent magnet Brushless DC (BLDC) motor has been designed with different rotor configurations based on the arrangement of the permanent magnets. Rotor configurations strongly affect the torque and efficiency performance of permanent magnet electric motors. In this paper, different rotor configurations of the permanent magnet BLDC motor with parallel the Halbach array permanent magnet were compared and evaluated. Many applications of electric drives or air-crafts have recently preferred the surface-mounted permanent magnet design due to its ease of construction and maintenance. The finite element technique has been used for the analysis and comparison of different geometry parameters and rotor magnet configurations to improve efficiency and torque performance. A comprehensive design of a three-phase permanent magnet BLDC 35kW motor is presented and simulations were conducted to evaluate its design. The skewing rotor and Halbach magnet array are applied to the permanent surface-mounted magnet on the BLDC motor for eliminating torque ripples. In order to observe the skewing rotor effect, the rotor lamination layers were skewed with different angles and Halbach sinusoidal arrays. The determined skewing angle, the eliminated theoretically cogging torque, and the back electromotive force harmonics were also analyzed.

This paper presents the harmonic torque reduction by the different rotor pole angles of a three-phase 12/8 switched reluctance motor via an analytical model and simulation method. Improving torque performance by stator and rotor angles was applied for three-phase switched reluctance motor at stator pole/rotor pole ratios of 6/4, 8/12, 18/12, and 24/18. The average torque and the torque ripple effect by stator and rotor pole embrace have been recently studied in many projects. Due to the fact that leakage flux, flux density, and inductance are affected by the stator and rotor pole angles non-linear and linear leakage flux curves occur. Many stator and rotor pole angle combinations for the three-phase switched reluctance motor have already been done via a finite element method. In this paper, turn-on and turn-off angles will be figured based on stator and rotor pole embraces.

This research proposes a robust correction procedure to improve inaccuracies around edges and corners inherent to thin shell electromagnetic problems by means of perturbation technique. This proposal is developed with three processes: A classical thin shell approximation replaced with an impedance-type interface condition across a surface is first considered and then a volume correction is introduced to overcome the thin shell approximation. However, the volume correction is quite sensitive to cancellation errors, with dramatic effects in the calculation of the local fields near edges and corners. Therefore, a robust correction procedure is added to improve cancellation errors of the volume correction. Each step of the developed method is validated on the practical problem.

This paper presents a subproblem approach with h-conformal magnetostatic finite element formulations for treating the errors of magnetic shell approximation, by replacing volume thin regions by surfaces with interface conditions. These approximations seem to neglect the curvature effects in the vicinity of corners and edges. The process from the surface-to-volume correction problem is presented as a sequence of several subdomains, which can be composed to the full domain, including inductors and thin magnetic regions. Each step of the process will be separately performed on its own subdomain and submesh instead of solving the problem in the full domain. This allows reducing the size of matrix and time computation.

This paper analyzes the electromagnetic and thermal design of interior permanent magnet motors using filled slots and hairpin windings for electric vehicle applications. Two models of ∇ shape of the interior permanent magnet motors have been proposed to evaluate the temperature distribution and cogging torque performance. A narrow opening slot of the interior permanent magnet of 48 slots/8 poles with the filled winding has been designed to investigate the electromagnetic torque because the cogging torque depends on opening stator slots. A parallel–rectangle slot of the interior permanent magnet with the hairpin winding has been also implemented with finite element analysis to evaluate their performances. Normally, the slot opening of the interior permanent magnet stator equals the slot width, it is greater than the size of hairpin windings, and the cogging torque is increased significantly with a bigger slot opening. The main advantage of the hairpin winding design is the high slot fill factors. Hence, the lower the current density, the higher torque, and efficiency are, than the normal design with the same geometry parameters. To improve the cogging torque due to the wide slot opening, the step–skew rotor slices have been arranged to minimize the torque ripple with different skewing angles.