IEEE Transactions on Magnetics最新文献

{"title":"Magnetostrictive Properties of Cubic Cu0.6Co0.4Fe2O4 and Tetragonal Cu0.8Co0.2Fe2O4 Under Pulsed High Magnetic Fields","authors":"Shizuka Kosugi;Takanori Kida;Masayuki Hagiwara;Satoshi Seino;Takashi Nakagawa;Shun Fujieda","doi":"10.1109/TMAG.2026.3685647","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3685647","url":null,"abstract":"To clarify the magnetostrictive properties of the Cu-substituted cobalt ferrites <inline-formula> <tex-math>$left(mathrm{Cu}_{x} mathrm{Co}_{1-x} mathrm{Fe}_{2} mathrm{O}_{4}right)$ </tex-math></inline-formula> with spinel-type cubic and tetragonal structures, the magnetic field dependence of the strain was measured up to the saturation state using pulsed high magnetic fields. At 300 K, the strain-magnetic field curve of the <inline-formula> <tex-math>$x=0.6$ </tex-math></inline-formula> sample with a cubic structure exhibited an extremum at approximately 1 T and then approached saturation. From the saturated values, the saturation magnetostriction constant <inline-formula> <tex-math>$lambda_{mathrm{s}}$ </tex-math></inline-formula> was estimated to be -249 ppm. At the same temperature, the strain of the <inline-formula> <tex-math>$x=0.8$ </tex-math></inline-formula> sample with a tetragonal structure varied gradually with increasing magnetic fields and approached saturation without showing an extremum. It was revealed that the <inline-formula> <tex-math>$lambda_{mathrm{s}}$ </tex-math></inline-formula> value of the tetragonal <inline-formula> <tex-math>$x=0.8$ </tex-math></inline-formula> sample was -309 ppm, which is larger than that of the cubic <inline-formula> <tex-math>$x=0.6$ </tex-math></inline-formula> sample. Furthermore, for the cubic <inline-formula> <tex-math>$x=0.6$ </tex-math></inline-formula> sample, the <inline-formula> <tex-math>$left|lambda_{mathrm{s}}right|$ </tex-math></inline-formula> value increased with decreasing temperature and showed a maximum at approximately 100 K. In contrast, the <inline-formula> <tex-math>$left|lambda_{mathrm{s}}right|$ </tex-math></inline-formula> value of the tetragonal <inline-formula> <tex-math>$x=0.8$ </tex-math></inline-formula> sample monotonically decreased. These results suggest that the temperature dependence of the magnetostrictive properties of <inline-formula> <tex-math>$mathrm{Cu}_{x} mathrm{Co}_{1-x} mathrm{Fe}_{2} mathrm{O}_{4}$ </tex-math></inline-formula> is strongly related to the crystal structure.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"2500906-2500906"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Optimization of a High-Power-Density Six-Phase PMSM for UAV Propulsion Considering Inverter-Induced Harmonic Effects","authors":"Min-Fu Hsieh;Anh Thanh Huynh;Pei-Yun Li;Minh-Hoc Duong Le;Po-Wei Huang","doi":"10.1109/TMAG.2026.3690525","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3690525","url":null,"abstract":"This article presents the design, analysis, and optimization of a high-power-density outer rotor permanent-magnet synchronous motor (PMSM) with six-phase configurations for uncrewed aerial vehicle (UAV) propulsion. Symmetrical six-phase (S6P), asymmetrical six-phase (A6P), and dual three-phase (D3P) windings are first evaluated within a unified design framework to compare torque capability, efficiency, and power density. A novel D3P winding arrangement is proposed that increases the winding factor from 0.808 to 0.933 and the phase inductance, thereby improving torque density and efficiency over conventional D3P designs. This article explicitly incorporates inverter effects into the design stage by analyzing the influence of pulse-width modulation (PWM) switching frequency and current harmonics on core loss, AC copper loss, inductance-related current ripple, and overall efficiency. The results show that increasing phase inductance suppresses PWM low-frequency current harmonics and mitigates ripple-induced loss, thus increasing motor efficiency. Furthermore, a multi-objective optimization framework combining Box–Behnken design, Krigingbased surrogate modeling, and a multi-objective genetic algorithm (MOGA) is employed to simultaneously maximize efficiency and power density while minimizing losses and motor mass. The optimized D3P motor achieves a power density of 5.21 kW/kg and an efficiency of 96.47%, outperforming the other six-phase configurations while offering enhanced fault-tolerant capability. Experimental results from a fabricated prototype validate the proposed design and analysis.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"8206106-8206106"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical Rotor Magnetic Field Modeling of Surface-Mounted PM Motors Considering Magnet Shaping and Manufacturing Tolerances","authors":"Peng Wang;Zhuoran Zhang;Chendong Liao;Jincai Li;Longxin Du;Chen Wang","doi":"10.1109/TMAG.2026.3688678","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3688678","url":null,"abstract":"This article proposes an analytical model for calculating the air-gap magnetic field of surface-mounted permanent magnet (PM) machines, considering magnet shaping and manufacturing tolerances. A segmentation and superposition approach is adopted to handle the nonuniform distribution of magnets induced by magnet shaping and manufacturing tolerances. The effectiveness of the proposed method is further validated by both finite element analysis (FEA) and experimental results.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"7503707-7503707"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimized Parallel-Resonant Impedance Matching for Railway Magnetic Field Energy Harvesting","authors":"Pilhoo Jeong;Hyunsoo Lee;Youbin Jun;Sungryul Huh;Seungyoung Ahn","doi":"10.1109/TMAG.2026.3702112","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3702112","url":null,"abstract":"This article presents an optimized impedance-matching strategy for magnetic field energy harvesting (MFEH) systems operating in railway catenary systems operating in railway catenary systems, where relatively low source currents (9–50 A) and high-resistance Internet of Things (IoT) loads require sufficient voltage boosting. Under these conditions, conventional series-resonant matching becomes inefficient because the limited source current cannot provide sufficient voltage gain for high-resistance loads, resulting in degraded power transfer performance. To address this limitation, a parallel-resonant impedance-matching framework is proposed. An analytical model is developed that incorporates the series quality factor and parasitic resistance to determine the optimal parallel capacitance and load resistance while accounting for resonance-frequency shifts and effective resistance transformation caused by parasitic losses. Circuit-level simulations under practical railway operating conditions verify that the proposed matching strategy significantly increases the harvested power and extends the unsaturated operating region compared with conventional series configurations. In particular, the parallel matching topology achieves higher output power and maintains stable operation over a wider load resistance range. The proposed framework provides practical design guidelines for railway magnetic field energy harvesting systems and enables accurate performance prediction and parameter optimization under realistic operating environments.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"8700206-8700206"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IEEE Magnetics Society Information","authors":"","doi":"10.1109/TMAG.2026.3740677","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3740677","url":null,"abstract":"","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"0004601-0004601"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11751703","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnet Segmentation Strategy Considering Electromagnetic Force in Large-Scale Wind Generators With Surface-Mounted Magnets","authors":"Wenting Wang;Yuqi Wang;Chenning Zhang;Hui Wen;Zhengxuan Xun;Lijian Wu;Tianjie Zou;David Gerada;Chris Gerada","doi":"10.1109/TMAG.2026.3700895","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3700895","url":null,"abstract":"Circumferential and axial segmentation are effective in reducing eddy current losses in magnets of large-scale wind generators. However, improper segmentation strategies can induce uneven electromagnetic forces (EFs) with pronounced fluctuations, threatening the reliability of magnet immobilization. This article investigates segment-level transient EFs and compares different segmentation strategies by jointly considering magnet fixation reliability and eddy current losses. The results indicate that axial-only segmentation with a sufficient number of segments provides a favorable compromise between magnet stability and eddy current loss reduction.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"8700306-8700306"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal Design of a High-Efficiency Permanent Magnet-Assisted Synchronous Reluctance Motor Considering Anti-Demagnetization Performance","authors":"Xiao Liu;Wei Zhao;Meng Lu;Dongpei Lu","doi":"10.1109/TMAG.2026.3689764","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3689764","url":null,"abstract":"To address the issues of low efficiency and susceptibility to demagnetization in ferrite permanent magnets for permanent magnet-assisted synchronous reluctance motors (PMaSynRMs), an optimal design method that comprehensively considers antidemagnetization performance is proposed. Based on anti-demagnetization analysis, design variables are determined under the constraint of a 5% maximum fault-current demagnetization rate. Moreover, a self-iterative expected improvement (EI) criterionbased kriging model is proposed, which automatically concludes the adding points process and improves the prediction accuracy of the surrogate model. Subsequently, multi-objective optimization, focused on improving efficiency and torque, is performed using a multi-objective particle swarm optimization (MOPSO) algorithm. The optimized motor achieves an efficiency of 94.9%, representing a 2.9% improvement over the initial design, while the maximum demagnetization rate of the ferrite under fault conditions is controlled within 4.91%. Experiments confirm an efficiency of 94.8% under rated operating conditions, a wide high-efficiency operating region, and satisfactory anti-demagnetization performance.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"8201306-8201306"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tailoring of Magnetic Properties and Giant Magnetoimpedance Effect in Co-Fe-Si-B-Ni-Mo Amorphous Microwires","authors":"Mohamed Salaheldeen;Valentina Zhukova;Pablo A. Rodríguez Jiménez;Julian Gonzalez;Arcady Zhukov","doi":"10.1109/TMAG.2026.3697711","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3697711","url":null,"abstract":"We studied the impact of heat treatment on the magnetic properties and Giant Magnetoimpedance (GMI) effect of Co-Fe-Si-B glasscoated microwires doped by Ni- and Mo. A substantial change in the hysteresis loop shape from linear to rectangular, a significant increase in the GMI ratio, <inline-formula> <tex-math>$Delta Z / Z$ </tex-math></inline-formula>, from ~370% up to ~<inline-formula> <tex-math>$470 %$ </tex-math></inline-formula>, and modification in the <inline-formula> <tex-math>$Delta Z / Z$ </tex-math></inline-formula> dependence on the magnetic field are observed. The observed dependencies are explained by a change in the magnetization reversal mechanism from magnetization rotation toward magnetization switching through the domain wall (DW) propagation. Such a change in the magnetization reversal mechanism induced by heat treatment is confirmed experimentally by the Sixtus-Tonks-like method, revealing fast DW propagation with velocities up to <inline-formula> <tex-math>$850 mathrm{~m} / mathrm{s}$ </tex-math></inline-formula>. The observed results are discussed in terms of internal stress relaxation and a domain structure modification upon heat treatment of the studied microwire.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"2003006-2003006"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting Seed Thickness: When Improved Texture Does Not Enhance Perpendicular Magnetic Anisotropy in Co/Pt Multilayers","authors":"Rico Ehrler;Felix Engelhardt;Olav Hellwig","doi":"10.1109/TMAG.2026.3693886","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3693886","url":null,"abstract":"We investigated the impact of the Pt seed layer thickness on the magnetic properties of [Co(0.4 nm)/Pt(0.7 nm)]25 multilayers(MLs) when using a Ta adhesion layer on an amorphous SiO₂ substrate. Using magnetometry, X-ray diffraction (XRD), and X-rayreflectivity (XRR), we quantitatively correlated the perpendicular magnetic anisotropy (PMA) with the seed roughness and MLtexture by fitting the XRR and defining a self-defined texture parameter, respectively. We find that, above a certain threshold,seed roughness and ML texture are correlated and increase with the seed’s thickness. Magnetically, we observe only small changesin PMA that are anticorrelated with the seed’s roughness, effectively reducing PMA at higher seed thicknesses despite improvedtexture. We propose a competition between detrimental roughness increases that reduce interfacial anisotropy and beneficial textureimprovements that increase magnetocrystalline anisotropy, which we validate by comparison to previous results. For Co/Pt MLswith very thin individual layers, we conclude that the underlayer roughness has a much stronger impact on the system’s PMA thanthe crystal quality, marking another important factor in tuning the magnetism of such MLs.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"2300906-2300906"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast Parameter Extraction of an Extended Jiles–Atherton Model Using a Physics-Constrained CNN–KAN Framework","authors":"Bohua Zhang;Martin Pfost","doi":"10.1109/TMAG.2026.3694643","DOIUrl":"https://doi.org/10.1109/TMAG.2026.3694643","url":null,"abstract":"Accurate hysteresis modeling is essential for high-frequency magnetic components, and the Jiles–Atherton (JA) model is widely used for this purpose. However, parameter identification remains computationally demanding, as traditional optimization approaches require iterative fitting of individual hysteresis loops (typically 1–2 min per loop) and scale poorly to large datasets. To address this limitation, a physics-constrained convolutional neural network and Kolmogorov–Arnold network (CNN–KAN) framework is proposed for fast parameter extraction of a delay-enhanced JA model. The proposed method directly takes the excitation waveform H(t) as input and incorporates experimentally measurable hysteresis features into a multi-objective loss function to enforce physical consistency. Using measured data ranging from 300 kHz to 1MHz from a TDK N49 toroidal ferrite core for training, the model achieves accurate reconstruction of hysteresis loops and reliable prediction of JA parameters within a single forward pass. Comparative evaluations against conventional optimization-based methods and alternative neural network architectures demonstrate a substantial reduction in computation time while maintaining high modeling accuracy. These results indicate that the proposed framework offers a scalable and efficient solution for high-frequency hysteresis modeling with the delay-enhanced JA model.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"62 10","pages":"7301405-7301405"},"PeriodicalIF":1.9,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11523595","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149249969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}