Conference Agenda

Permanent Magnet Synchronous Motors (PMSMs) are no longer un-fimillar to industrial applications due to their high torque and power density, high efficiency, reliability and excellent dynamic performance. Six-phase PMSMs represent an important step forward in enhancing overload capability and fault tolerance of these motors. With outer rotor (OR), PMSMs increase the ability to produce more torque, making them especially suitable for traction applications i.e. ship propulsion, lifting, mining, oil exploitation, etc. This study proposes an optimal design strategy for six-phase OR SPMSM using particle swarm optimization (PSO). Firstly, an analytical method is introduced to calculate the main dimensions of a 155kW six-phase OR PMSM with 10-pole/30-slot combination. Next, an optimal method using PSO is developed by MATLAB programming with objective functions focusing on minimizing total losses of iron and copper as well as material cost. The finite element method is then employed to calculate electromagnetic parameters of motors to validate the accuracy of the proposed analytical method and optimal design. The results of the motors are analyzed and compared, showing that after optimization process, the efficiency of the motor increases by 0.2% along with a reduction of 54$ in material cost. Moreover, other electromagnetic parameters such as back EMF THD, torque ripple are improved in comparison to the initial motor design.

This paper proposes a novel design methodology aimed at efficiently reducing the computation costs associated with axial flux permanent magnet synchronous motors (AFPMM). The proposed method utilizes the analysis results of the initial position of the rotor, called initial state finite element analysis (ISF), as a 3-dimensional analysis of AFPMM, and generates a surrogate model using machine learning. This approach can significantly reduce the computation time required to analyze the nonlinear characteristics of the motor, as it eliminates the need for any additional periodic analysis. The performance of ISF will be verified through comparison with full periodic finite element analysis (FPF). The machine learning model used for optimization of the proposed method is LightGBM, and its performance will be verified through comparison with other ML models using test functions. By combining many samples generated at low computational costs through ISF with LightGBM, the method aims to perform optimization and achieve the numerous required performances of electric vehicle (EV) driving motors.

This paper presents a computationally efficient and reliable method for designing conductor shapes in wound field synchronous motors (WFSM) with hairpin windings to enhance efficiency considering AC ohmic loss. First, a hybrid method combining magneto-static analysis and analytical modeling is proposed for the accurate and practical estimation of AC resistance and loss. The proposed method is validated through detailed comparisons with conventional transient analysis, demonstrating high accuracy and consistency. Additionally, the optimal conductor shape is designed by applying the previously proposed method. The optimization framework considers variations in conductor geometry and their impact on iron loss. Motor parameters, including current vectors and field current, are analyzed to minimize total losses across various operating conditions. Finally, the optimal conductor shape and motor design are determined to achieve maximum efficiency.

This paper proposes a design for a permanent magnet assisted synchronous reluctance motor (PMa-SynRM) with a focus on mechanical robustness. Permanent Magnet Synchronous Motors (PMSMs) are widely used for their high performance and efficiency, achieved through the use of rare-earth permanent magnets. However, the use of rare-earth magnets poses economic challenges in terms of motor design and maintenance. To address this, research is being conducted on PMSM designs that incorporate non-rare-earth materials. The PMa-SynRM is a variation of the Synchronous Reluctance Motor (SRM) that uses non-rare-earth permanent magnets in the rotor to improve power factor and output. Consequently, PMa-SynRM requires a multi-layer arrangement of permanent magnets, which complicates miniaturization and introduces vulnerabilities to stress. This paper analyzes the correlations between design variables affecting both electromagnetic performance and stiffness, using optimization algorithms. The findings of this study are expected to be valuable for selecting critical design parameters in the initial design phase of PMa-SynRM.

In recent decades, we have observed a rapid development of new metaheuristic algorithms due to many factors. One of these factors is the increasing complexity of real-world problems, which make them very challenging for traditional algorithms. Another important factor is the advancements in hardware and parallel processing which have significantly enhanced the computational capabilities of modern computers, enabling the implementation of more sophisticated algorithms. The aim of this paper is to evaluate and compare the performance of several modern metaheuristic algorithms for the optimal design of electromagnetic devices. This comparative study analyzes each algorithm, highlighting their strengths and limitations. By systematically examining their performance, we seek to provide insights into which methods are most suitable for addressing the complexities of electromagnetic device optimal design.

The study of the molecular level effects in blood cells of the variable magnetic field requires the design of appropriate magnetic devices. In this article, four immobile configurations are analyzed: Helmholtz coils, Gramme coils, quadrupole magnet, and sextupole magnet. These devices can create a rotational magnetic field, intense (up to hundreds of mT), of high frequency (up to 1 MHz) and with an appropriate degree of homogeneity (minimum 95%) in the bioreactor area of 1 cm in diameter. The rotational field is created by supplying the component coils by currents having shifted phases. The original comparative numerical analysis with the help of COMSOL software highlighted the effect of the device geometry, the type of core and conductor, correlated with the working frequency, on the magnetic field level in the area of the blood cells.

In this paper, the optimal design of hybrid hairpin winding permanent magnet synchronous generator(PMSG) for gas turbine engine is derived considering the reduction of AC copper loss. The hybrid hairpin winding includes aluminum conductor to overcome the weakness of AC copper loss by the wide area of the hairpin winding. The aluminum conductors have lower electrical conductivity than copper conductors and trade-off relationship between DC and AC copper losses. In case of PMSG for gas turbine engine, the operating region is focused on high-speed region, so the effect of reducing AC copper loss is emphasized. The material combination and size of the conductors were optimized based on the algorithm to reduce the copper losses including AC and DC copper losses. In addition, the weight and cost of PMSG were also reduced according to the characteristics of aluminum.

Synchronous motors with PWM control are the main ones. When a motor is driven through PWM control, the current waveform considering PWM control shows a different waveform from the sinusoidal current waveform used for general Finite Element Method (FEM) analysis. It is a waveform with harmonics in a sinusoidal current waveform, and this harmonic component has a great effect on eddy current loss generated in permanent magnets, and this eddy current loss causes demagnetization in permanent magnets and affects motor performance. In this paper, the magnet division method is selected as a method to reduce eddy current loss per unit volume, and the reduction of eddy current loss per unit volume according to the decrease in length of the magnet is confirmed. In addition, the effect of harmonics on the eddy current loss of the permanent magnet is confirmed by comparing the current waveform considering PWM with the sinusoidal current waveform. The validity of the above points is verified through FEM.

This paper proposes a methodology to reduce electromagnetic vibration of 10 pole 12 slot permanent magnet synchronous machine (PMSM) by mitigating 2nd and 10th order radial force, which have critical impact on generation of vibration. By deriving an equation that describes the relationship between the radial force and flux density harmonics, flux density harmonics of permanent magnet (PM) field and armature reaction field, which should be minimized to reduce 2nd and 10th order radial force are identified. Based on the equation, coupled with flux density analysis, PM angle is determined, and notches are grooved on the stator tooth. As a result, 2nd and 10th order radial force is reduced so that the electromagnetic vibration of 10 pole 12 slot PMSM is decreased.

Slotless permanent magnet synchronous motor (PMSM) are widely used in precision and high-speed applications but face significant AC copper loss due to direct flux linkage with the windings. This study uses finite element analysis (FEA) to investigate the mechanisms of AC copper loss in slotless PMSM. Results show that wire diameter and flux linkage are the primary factors: increasing wire diameter from 0.2 mm to 0.6 mm raises AC copper loss by 577%, while shifting the wire position to reduce flux linkage lowers it by 8.27%. These findings highlight the importance of conductor size and placement in reducing losses. Future research will examine the effects of number of turn, number of pole, and wire shape, and validate the analysis results through prototype testing.

In electrical regenerative braking systems, permanent magnet synchronous motors with fractional slot combinations are commonly used. Concentrated windings with lap winding configurations are typically employed. However, for compact 500 W-class motors, achieving a slot fill factor exceeding 50-60 % with conventional lap-wound concentrated windings poses significant challenges, limiting motor miniaturization. This paper explores the design of a size-reduced motor using maximum slot occupation (MSO) coils, which enable a slot fill factor exceeding 80 %. To verify the effect of the MSO coil only, the rotor geometry was designed to match the prototype. The performance of the designed model was evaluated using finite element analysis and d- and q-axis equivalent circuit analysis. The results confirm that the proposed design maintains comparable performance to the prototype while achieving approximately 28 % reduction in the stator core volume.

This paper proposes a computationally efficient sensitivity analysis method to evaluate the impact of manufacturing uncertainties on Surface Permanent Magnet Synchronous Motors (SPMSMs). Key tolerances, including geometric and material variations, are analyzed using an analytical approach, reducing the reliance on computationally intensive finite element analysis (FEA). Latin Hypercube Sampling (LHS) is employed for experimental design, with performance and robustness quantified through variance analysis. Finally, the proposed process is validated against FEA and prototype testing.