This study focuses on a 2-pole induction motor with concentrated winding. A conventional 2-pole induction motor with distributed winding increases its motor size due to its large coil end height. An induction motor with concentrated winding is applied to decrease the height. However, the second component of the magnetic flux rotates in the opposite direction with the fundamental magnetic flux, and generates negative torque. In this study, a 2-pole induction motor with concentrated winding where a magnetic modulation is used is proposed. The operational principle is mathematically described, and the magnetic flux density is computed in a variety of pole-slot combinations. Finally, a transient analysis with motion equation is conducted to investigate the operational principle.

This study proposes a novel rotor structure for spoke-type Interior Permanent Magnet (IPM) motors. In this proposed structure, magnets molded into a flask shape are arranged radially in the rotor, similar to conventional spoke-type IPM motors. This design allows the magnets to be jammed onto the rotor core, holding them against centrifugal forces. Consequently, the bridges used to retain the magnets—a primary path for leakage flux in conventional structures—can be eliminated, which in turn increases the rotor flux.
The advantage of the proposed structure is the reduction of leakage flux, enabling it to achieve higher torque compared to conventional spoke-type IPM motors with an equivalent amount of magnets. To validate its effectiveness, the magnetic and strength characteristics were evaluated using numerical analysis via the Finite Element Method. Furthermore, the obtained results were compared with those of a conventional motor. Both the numerical analysis and experimental tests on a physical prototype confirmed that the maximum torque of the proposed motor exceeds that of the conventional motor.

In this research, a novel rotor structure is proposed for V-shaped interior permanent magnet (IPM) motors. By using V-shaped IPM motors, concentrated flux can be generated on the d-axis, resulting in a high torque density. However, there was a design issue, which was the leakage flux generated on the outer bridge. In the proposed motor, trapezoidal magnets are inserted into the rotor core instead of the conventional rectangular magnets. The width of the magnet is gradually narrowed in the radial direction so that the magnet can be supported by the rotor core without outer bridges. In this study, numerical verification and experimental verification were conducted to validate its effectiveness. From the numerical results and experimental results, it was confirmed that the volume of magnets required to obtain the desired torque was reduced by 10.2% compared to conventional V-shaped IPM motors.

Weight reduction of actuators, the main parts of collaborative robots (Cobots) is required for Cobots that can operate without a safety fence, because it improves the speed, safety, and ease of changing the layout of Cobots. One approach to realize it is reducing the weight of the motor while keeping the output torque.
Therefore, aiming at the motor with higher torque density, this research has proposed Magnetic Worm-Geared Motor (MWGM) imitating worm gear, and improved its torque density by introducing a claw-pole structure. However, it is not clear how much torque the integrated magnetic worm gear amplifies.
This presentation compares torque performance between MWGM and Permanent Magnet Vernier Motor (PMVM), which has the function of magnetic gear and exhibits high torque at low speed. In order to compare the theoretical and actual torque between both motors, two types of material are applied to the stator core. This analysis changes the material in one study by using the material variable function of JMAG-Designer (JMAG is the trademark of JSOL Corporation), thus reduces the effort to set up and run the study for each material. The analysis result shows that MWGM has better performance when magnetic saturation is neglected, but the performance is suppressed to the level of PMVM actually due to the saturation.

With the growing awareness of environmental issues, the development of electric agricultural and construction machinery has been accelerating in recent years. The electric motors installed in these machines are required to deliver high torque within limited spaces. As a promising candidate to meet such requirements, the axial-flux permanent magnet (AFPM) motors have attracted attention.
However, AFPM motors cannot be analyzed using a simplified two-dimensional (2D) model like radial-flux PM motors because their structure is non-uniform along the axial direction. Therefore, when applying optimal design methods, a 2D linear model is often employed. Nevertheless, this model cannot accurately represent flux distribution and eddy currents in the permanent magnets, which may cause large errors in loss estimation, especially at higher frequencies.
In this study, optimizations are performed using both a large-scale three-dimensional (3D) model with a supercomputer and a 2D linear model while varying the operating frequency. By comparing the results, the frequency limit at which the 2D linear model can achieve practically acceptable accuracy is investigated.

To address the issue of stable supply of rare earth magnets, motors that do not use neodymium magnets are being sought. Furthermore, permanent magnet motors face challenges such as reduced efficiency in high-speed rotation ranges and short-circuit current issues during failures, both caused by the high magnetic flux of the　permanent magnets. To solve these problems, we propose a Permanent Magnet Synchronous Motor that uses ferrite magnets and alnico magnets as auxiliary magnets, allowing the magnetic flux of the permanent magnets to be varied for driving in both low-speed and high-speed regions. JMAG analysis confirmed that the proposed motor can generate approximately 1.6times the torque of a Synchronous Reluctance Motor, and can also be driven as a reluctance motor with the magnet flux set to zero.

In recent years, growing interest in natural energy has promoted the use of offshore wind power generation. However, mechanical gears face maintenance problems due to friction and heat generation. In contrast, non-contact magnetic gears are expected to be the next generation of gears because they inherently generate less vibration, noise, and dust, making them easier to maintain.
Among various types of magnetic gears, flux-modulated magnetic gears are the most promising for practical applications due to their high torque density and efficiency, as all magnets in the inner and outer rotors constantly contribute to torque transmission. On the other hand, reducing the amount of magnets used in the inner and outer rotors and achieving weight reduction are important issues from the cost-reduction.
The diameter of magnetic gears used in offshore wind turbines can reach approximately 10 meters, making it challenging to optimize the magnet geometry using 3D electromagnetic field analysis by FEM due to the model size.
Therefore, this study investigates the optimization of magnet geometry using large-scale parallel computation with a supercomputer, aiming to improve torque-to-weight ratio and reduce the amount of magnets in large magnetic gears for offshore wind turbines.

Transverse-Flux-Type Switched Reluctance Motor (TFSRM) enables a high winding space factor due to its toroidal winding configuration. Therefore, it is expected to include higher torque compared to conventional SR motors. Previous studies have reported the relationship between TFSRM structural parameters and torque when using linear materials, specifically concerning the number of poles, stator yoke, and stator pole width. However, the relationship between structural parameters and torque when using nonlinear materials remains unclear. Therefore, this paper uses 3D-FEM to clarify the influence of the stator yoke and pole width on torque when using non-linear material, namely non-oriented electrical steel sheet.

As electric mobility advances, motors that can simultaneously provide a wide speed range and reduced weight are increasingly required. Conventional Variable Magnetic-Flux PMSMs need dedicated field windings and circuits, which enlarges the system. This paper therefore proposes an axial-gap PMSM that controls the field using the magnetomotive force of the stator coil ends together with a DC zero-sequence current i_z. A dual-inverter configuration is adopted so that i_z is supplied independently of the d-q currents. A consequent-pole structure is applied to the rotor core, allowing the polarity of i_z to switch the magnetic poles between S and N and thereby increase or decrease the air-gap flux density. Electromagnetic field analysis and circuit simulation are used to compare the proposed motor with a conventional PMSM and with a Variable Magnetic-Flux PMSM employing field windings. The results show that a negative i_z can weaken the flux nearly to zero, while a positive i_z enhances torque: under an identical line current of 6.5A_{rms}, the maximum torque increases by about 32% at i_z=3.5A_{DC/phase}. Moreover, compared with the field-winding approach, the proposed motor achieves approximately 39% higher torque and a wider speed–torque (N–T) operating range. These findings demonstrate the effectiveness of the proposed method in enabling field control without additional field windings.

The finite element method (FEM) is widely used for electromagnetic field analysis and enables high‑accuracy simulation. However, a major drawback is the substantial increase in computation time as the number of elements grows. For determining control parameters in real‑time control, there is a need not only for faster computation but also for compatibility with multiphysics analysis. In this presentation, we focus on the Cauer Ladder Network (CLN) method—one of the model order reduction (MOR) techniques for accelerating analysis—and report a method that replaces a three‑dimensional (3D) FEM model with an equivalent circuit based on a multiport Cauer ladder network.

Magnetic field homogeneity is crucial for enhancing the performance of MRI and NMR systems. The optimal design of correction coils is an effective method for compensating for magnetic field inhomogeneities (error fields) that arise during manufacturing. However, conventional coil design is often based on idealized error fields, making it difficult to accurately reflect the complex field distribution unique to the actual device, which is caused by factors such as variations in individual magnets and positioning errors.
In this presentation, we propose a method to address this issue by designing tailor-made correction coils directly from measured three-dimensional magnetic field distributions. First, the magnetic field distribution in the target space is precisely measured. Then, based on this measurement data, the optimal current distribution required to generate a target magnetic field that cancels out the error field is calculated using the stream function method, which is accelerated by the Adaptive Cross Approximation (ACA).
This integrated process allows for the efficient design of correction coil shapes based on the specific characteristics of the actual device, rather than relying on idealized simulations. For future work, we plan to fabricate the coil designed by this method using a metal 3D printer and validate its effectiveness through magnetic field distribution measurements and NMR measurements on the actual system.

In particle-beam radiotherapy accelerators, high-precision beam delivery tailored to a patient’s tumor geometry is essential.
Consequently, it is critical to generate magnetic fields that accurately account for the magnetic hysteresis in the iron cores of accelerator magnets.
The play model, a class of hysteresis models, allows for the deterministic identification of its parameters by estimating the shape function via the Everett function.
It is therefore considered effective in applications demanding high reproducibility, such as computing the fields produced by accelerator magnets.
Furthermore, magnetic field analysis based on the magnetic scalar potential method which enables efficient computation is widely used in the accelerator community.
Because the numerical solution obtained with this method is the magnetic field H, it is considered well-suited for an H-input play model.
However, our research suggests that a B-input play model may achieve superior fidelity when reproducing measured asymmetric minor loops.
In this work, we investigate the underlying cause of this discrepancy by focusing on the congruency property of minor loops inherent to the play model.
To this end, we developed a dSPACE-based measurement system capable of acquiring B-H loops under arbitrary waveforms.
This presentation reports on the construction of this system and presents preliminary results from a comparative evaluation of the reproduction accuracy of B-input versus H-input play models.

Multi-Mode Reluctance Motor (MRM) drives on both high-efficiency SynRM and high-power SRM modes with a single structure for performance improvement. Furthermore, MRM is a novel type of low-cost mode-switching motor without permanent magnet, multiphase winding or changeover winding. 12-pole 20-slot five-phase MRM is a promising model considering both performance and cost. However, mode-switching motors including MRMs have a common challenge for the performance trade-offs between their multiple modes. This presentation investigates the design optimization method to achieve MRMs that balance the performance between SynRM and SRM modes. This method utilizes the multi-objective genetic algorithm engine and the multi-study analysis tool of JMAG-Designer to handle two different modes. Moreover, the application of current vector control specific to five-phase MRM reduces the required analysis step and the time for design optimization process.

In automobiles, various driving environments such as urban driving and highway driving and etc., so motors for EV require a wide range of operating range. In response to such requests, Induction Motor Transmission System(IMTS) using multiple units of inverters is considered to be valid. In the IMTS, the same structure is used to change pole number, so it is desirable to explore geometry suitable for each pole driving by using optimization. However, analysis time for IM is longer compared to other motors, so multiple analysis such as geometric optimization comes with constraints core numbers and etc. in the local PC.
In this presentation, we report the methods of using JMAG in the supercomputer and suitable geometry for each pole driving in the IMTS by performing multi-objective geometric optimization analysis using supercomputer “TSUBAME 4.0”.

High-precision beam control is required in particle-beam therapy accelerators to match the patient’s tumor geometry.
To achieve this, magnetic field generation must account for the magnetic hysteresis of accelerator magnet cores.

The play model, which determines its shape function based on the Everett function, is a deterministic and highly reproducible method for magnetic field analysis.
In this study, we constructed a Reduced Play Model that maintains the original framework of the play model while reducing its dimensionality to extract dominant magnetization responses.

Magnetic field distributions on the midplane were obtained using finite element analysis, and the shape functions were identified through the Everett function.
The proposed model achieved a significant reduction in computation time while maintaining accuracy comparable to that of FEM.

Future work focuses on extending the model by using a user subroutine to calculate and reflect magnetic co-energy during analysis, enabling reproduction of hysteresis behavior consistent with real magnetization processes.

This poster presents the proposed Reduced Play Model, which reproduces hysteresis in accelerator magnets with both high fidelity and computational efficiency, and outlines its implementation method.

To realize a decarbonized society, the practical application of wireless power transfer to electric vehicles during operation is anticipated. This study measured the electrical characteristics and transmission efficiency of coils under two conditions—insulated reinforcing bars and untreated reinforcing bars—to clarify the impact of reinforcing bars within the road on the power transfer coils. These results were compared with analysis results obtained using JMAG. The results showed good agreement between analysis and measurement values for the receiving coil, while errors occurred in the transmitting coil due to factors like ferrite effects. Furthermore, it was confirmed that eddy current losses were significantly reduced by the insulation treatment. Future work will aim to improve analysis accuracy using models closer to actual rebar shapes.

In recent years, the demand for high–power-density converters has been increasing in applications such as data center UPS systems and hybrid electric vehicles (HEVs).
Large inductors used in these converters are essential passive components, and accurate loss evaluation is required. However, for large inductors, it is necessary to consider the non-uniformity of magnetic flux density.
In this study, an analytical method combining the loss map approach and finite element method (FEM) analysis is proposed to accurately predict the iron loss of large toroidal AC filter inductors under PWM inverter excitation.
The proposed method introduces a radial model that analytically represents the spatial distributions of magnetic field and flux density, enabling iron loss evaluation that accounts for flux density non-uniformity.
Furthermore, by comparing the measured results obtained from experiments with the analytical results derived from the proposed method, the effectiveness of the proposed approach is demonstrated.
As a result, it is confirmed that the proposed method enables accurate and efficient iron loss prediction for large toroidal inductors under PWM excitation.

Based on Life Cycle Assessment (LCA), the environmental impacts during manufacturing and driving were compared and evaluated for five types of automotive motors: copper-wound PMSM, SynRM, PMaSynRM, IM and aluminum-wound PMSM.
The usefulness of aluminum windings and rare-earth-free motors is assessed from the perspective of environmental impact. In addition, the challenges in designing aluminum-wound PMSMs with the same size and slot fill factor are also presented.

In recent years, the demand for electric vehicles have been increasing, meaning that high performance traction motors are desired. This research investigated a structure that achieves low torque ripple, low loss, and high manufacturability in high-speed traction motor with a maximum rotational speed of 30,000 rpm. Skewed rotor structures are commonly used to reduce torque ripple and cogging torque, but these have issues such as increased manufacturing costs and increased loss due to axial leakage flux. Hence, this study proposed a fractional slot structure and compared it with conventional structures using skewed rotor in terms of torque ripple and loss using JMAG. The results revealed a structure that is superior to conventional skewed structures.