CES Transactions on Electrical Machines and Systems最新文献

{"title":"Novel Asymmetric IPM Rotor Design Using Cascaded Multiphysics Topology Optimization","authors":"Mohamed Reda Mahmoud;Mohamed N. Ibrahim;Peter Sergeant","doi":"10.30941/CESTEMS.2026.00018","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00018","url":null,"abstract":"Sustainable motor design is crucial for improving energy efficiency and reducing material consumption. This paper introduces a novel asymmetric interior permanent magnet (IPM) rotor design using topology optimization (TO). The study employs a two-stage TO approach to design IPM rotor. In the first stage, a multi-objective electromagnetic TO is conducted to enhance the average torque and reduce the mass of the magnetically active rotor zone. In the second stage, structural TO is performed to minimize the mass of the magnetically inactive rotor zone while maintaining mechanical integrity, ensuring the rotor withstands operational mechanical stresses. The asymmetric topology-optimized IPM (ATO-IPM) machine is analyzed and benchmarked against the conventional IPM design and the symmetric topology-optimized IPM (STO-IPM) design. The results indicate that the asymmetric flux barriers enhance the torque performance. The ATO-IPM design offers significantly more efficient utilization of permanent magnets (PMs) and improved torque density by approximately 13.3% compared to the conventional IPM motor. Moreover, ATO-IPM design supports the advancement of sustainability by improving efficiency by 2.3% compared to conventional design. Furthermore, ATO-IPM designs save about 46.7% of the amount of silicon steel of the conventional topology.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 2","pages":"153-165"},"PeriodicalIF":0.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11595069","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148443057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LPF-Free Harmonic Current Control in Multi-Synchronous Reference Frames for Dual Three-Phase PMSMs","authors":"Yulei Yang;Qian Wang;Fangrui Wei;Yichen Yu","doi":"10.30941/CESTEMS.2026.00013","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00013","url":null,"abstract":"Harmonic current regulation in multi-phase motor drives remains challenging under dynamic operating conditions due to non-sinusoidal back electromotive force (EMF) and inverter nonlinearities, which introduce dominant low-order harmonics. Multi-synchronous reference frame (MSRF) based methods are widely adopted for multi-frequency current regulation; however, conventional implementations typically rely on low-pass filters (LPFs) for harmonic decoupling, introducing detection delay and phase distortion that limit transient performance. This paper proposes an LPF-free MSRF-based harmonic current control method for dual three-phase permanent magnet synchronous motor (DTP-PMSM) drives. By introducing harmonic transformation matrix coefficients (HTMCs), the proposed method retains the independent regulation of multiple harmonic components within the MSRF framework, while eliminating the filtering step in the harmonic decoupling path, without the need for harmonic plane reconstruction or additional coordinate transformations. To support adaptive changes, a Goertzel-based harmonic amplitude extraction scheme is employed to periodically update the HTMC. Experimental results demonstrate that the proposed method significantly enhances dynamic performance, achieving a 19.3% reduction in speed transition stabilization time compared to other methods. The proposed LPF-free formulation provides a practical solution for MSRF-based harmonic current control in industrial motor drive applications where fast dynamic response is required.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 2","pages":"216-227"},"PeriodicalIF":0.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11495399","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148442260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Power Factor Analysis of Flux Modulated Dual-PM Excited Machines based on PM and Armature Flux Linkages","authors":"Hong Chen;Yao Meng;Boyi Li;Dawei Li;Ronghai Qu","doi":"10.30941/CESTEMS.2026.00011","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00011","url":null,"abstract":"Flux modulated dual-permanent magnet (PM) excited machine (FMDPMM) has become a promising candidate for direct-drive applications, featuring high torque density and efficiency. However, it usually suffers from a low power factor (PF) due to the imbalanced PM and armature flux linkages, which are mainly caused by the abundant PM and armature field harmonics. To address the problem, a comprehensive PF analysis of FMDPMM is conducted in this paper based on PM and armature flux linkages. First, the dominant PM and armature field harmonics contributing to the corresponding flux linkages are investigated using a simplified magneto motive force (MMF)-permeance model. Based on the qualitative analysis, several practical design guidelines are presented to improve the PF of FMDPMM. Then, the dominant field harmonics and flux linkage contributions of two FMDPMMs with different PM arrangements and winding configurations are comparatively analyzed, quantitatively verifying the effectiveness of the proposed guidelines for PF improvement. The results demonstrate that, by taking advantage of high PM flux linkage, low non-working armature flux linkage, and proper filtering effect of armature windings, MDPMM can simultaneously achieve a high PF and a large torque density. Finally, a prototype is manufactured for validation.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 2","pages":"166-175"},"PeriodicalIF":0.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11482263","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148442741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Electrically Excited Synchronous Machines Using Copper and Aluminum Windings in Stator and Rotor","authors":"Tianzheng Xiao;Zi Qiang Zhu;Ziad Azar","doi":"10.30941/CESTEMS.2026.00008","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00008","url":null,"abstract":"In this paper, electrically excited synchronous machines (EESMs) using copper (Cu) and aluminum (AI) windings are compared for the feasibility of replacing Cu windings with Al windings in electric vehicle (EV) applications since Al windings have lower mass density and cost per weight, but higher resistivity and lower thermal conductivity than Cu windings. The EESMs with four winding configurations are optimized with an electromagnetic-thermal co-optimization method. The optimized EESM with only Cu windings is considered as the baseline in this study. Results show that the EESM with stator-Cu/rotor-Al windings has the least torque reduction (12.1%) compared to the baseline among the three EESMs with Al windings and the highest torque mass density among all EESMs. Meanwhile, although the new European driving cycle efficiency of the stator-Cu/rotor-Al EESM is 1.8% lower than that of the baseline, the torque per cost is 71% higher, and the maximum rotor mechanical stress is 8% lower. Therefore, the EESMs with stator-Cu/rotor-Al windings are prospective substitutions of those with only Cu windings for EV applications considering the trade-off between performance and cost.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 1","pages":"16-27"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11470992","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147584933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fault-Tolerant Control and Fault Diagnosis of Symmetrical Six-Phase Permanent Magnet Synchronous Motor Drives without Controller Reconfiguration","authors":"Aihua Liu;Feng Yu;Qingan Zhu;Xiaoxin Wu","doi":"10.30941/CESTEMS.2026.00002","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00002","url":null,"abstract":"Owing to the multi-degree-of-freedom characteristics and inherent fault-tolerant capacity, six-phase motors have been widely adopted in high-power applications, such as electric vehicle propulsion and aerospace systems. This paper presents the fault-tolerant control strategy of symmetrical six-phase permanent magnet synchronous motor (SSPMSM) under an isolated neutral point topology and proposes a fault diagnosis scheme based on joint diagnosis of multiple variables. First, two mathematical models of SSPMSM and their relationship are established. Subsequently, the current vectors in the torque subspace and harmonic subspace of the two winding sets under fault conditions are analyzed, and the cause of post-fault torque ripple is explained as resulting from controller conflict. In addition, a multivariate fault diagnosis scheme based on voltage threshold in the <tex>$boldsymbol{x}-boldsymbol{y}$</tex> subspace and current trajectory characteristics in the <tex>$boldsymbol{alpha}-boldsymbol{beta}$</tex> subspace is proposed to enhance the diagnostic accuracy. Finally, the feasibility and stability of the proposed control and diagnosis methods are verified by experiments.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 1","pages":"87-96"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11471012","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147584923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiparameter Estimation of PMSM Combining Mechanical and Electrical Models with Nonlinear Saturated Inductance and Voltage Fitting","authors":"Lupeng Yang;Yuting Lu;Guodong Feng;Yu Han","doi":"10.30941/CESTEMS.2026.00007","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00007","url":null,"abstract":"In this paper, a precise and computationally efficient method for estimating multiparameter of permanent magnet synchronous motors (PMSMs) is proposed. This method can realize decoupling estimation with a small amount of data at a single speed, and considers the inductance correlation to improve the estimation accuracy. The saturation in the stator frame is first modeled, and then the related inductance model in the rotating frame is derived. The estimation model is established based on the related inductance model, which is modeled by polynomials of d-axis current <tex>$(boldsymbol{I}_{mathbf{d}})$</tex> for a given q-axis current <tex>$(boldsymbol{I}_{mathbf{q}})$</tex>. Then, the influence of permanent magnet (PM) flux linkage on inductance estimation can be eliminated by using the partial derivative of the correlated inductance model. The estimation model fully explores the inductance correlation and can realize the decoupling of PM flux linkage <tex>$(boldsymbol{lambda}_{mathbf{0}})$</tex> and inductance, which greatly improves the inductance estimation accuracy, especially when <tex>$boldsymbol{I}_{mathbf{d}}$</tex> is small. Moreover, this paper realizes the estimation of distortion voltage, PM flux linkage, and stator resistance based on the derived electrical model and mechanical model. Compared with the existing method, this method can use a small amount of data at a single speed to model voltage, which can effectively reduce the influence of measurement noise and improve the calculation efficiency. Experimental verification on a laboratory PMSM prototype shows that the method's performance of the proposed method is better than existing methods under various working conditions.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 1","pages":"109-120"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11470993","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147584925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced Repetitive Control with Phase Compensation Based ADRC for Harmonic Suppression in Magnetically Suspended Rotor Under Strong Gyroscopic Effects","authors":"Yuxiang Zhu;Fanqiang Gao;Kaiyu Shan;Zixin Li;Yaohua Li","doi":"10.30941/CESTEMS.2026.00003","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00003","url":null,"abstract":"Magnetically suspended rotor (MSR) systems have gained widespread industrial adoption owing to their frictionless operation and exceptional reliability. However, harmonic current generated by unbalanced mass and sensor runout threatens the system stability. Repetitive control (RC) effectively suppresses harmonic current, but its parameter design relies on an accurate decoupling model of the system. The decoupling model for the MSR system is often simplified to a second-order linear system. Such a simplification, however, necessitates explicit consideration of system uncertainties caused by unmodeled nonlinearities during the RC design process. Especially under strong gyroscopic effects, the parameter uncertainty is further increased. In this article, an active disturbance rejection controller (ADRC) based on phase compensation (PC) is used to suppress coupling disturbances and improve the control performance of harmonic suppression. Firstly, the dynamic model of the MSR system is established, and both internal and external disturbances are thoroughly analyzed. Then, the RC-PCADRC scheme is designed, integrating the complementary strengths of RC and ADRC, with a particular emphasis on PC to improve stability margins. A comprehensive stability analysis is conducted, along with parameter optimization guidelines. Finally, the effectiveness and superiority of the proposed scheme are validated through both simulations and experiments.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 1","pages":"97-108"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11470990","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147584932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asymmetric Voltage Vector-Based Initial Rotor Position Detection in Four-Switch Inverter Fed BLDC Motors","authors":"Xinmin Li;Kun Liu;Lu Zhou;Tingna Shi;Wei Chen","doi":"10.30941/CESTEMS.2026.00005","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00005","url":null,"abstract":"In position-sensorless brushless direct current (DC) motors (BLDCMs) fed by a four-switch three-phase (FSTP) inverter, only two phases are fully controlled, while the remaining phase is tied to the midpoint of the split DC-link capacitors. The voltage pulses required by inductance-based initial position detection can cause unequal discharge of the series capacitors, shifting the neutral-point voltage away from half of DC-link voltage <tex>$(boldsymbol{U}_{mathbf{dc}}/mathbf{2})$</tex>. This neutral-point drift breaks the spatial symmetry of the inverter voltage vectors, so the 360° electrical period can no longer be evenly partitioned into six sectors during initial rotor position detection. To address this issue, this paper proposes a detection-pulse injection sequence that explicitly accounts for the asymmetric voltage vectors of the FSTP inverter. With the proposed sequence, the initial rotor position can be identified within a 30° electrical sector. The method requires no additional voltage or current sensors, and experimental results confirm its feasibility.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 1","pages":"77-86"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11471013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147584939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Step-Up 25-Level Inverter Topology for Photovoltaic Systems","authors":"Fatemeh Esmaeili;Hamid Reza Koofigar;Frede Blaabjerg","doi":"10.30941/CESTEMS.2026.00004","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00004","url":null,"abstract":"Integration of renewable energy sources into power systems requires efficient multilevel inverters, capable of producing high-quality output voltage with low total harmonic distortion (THD). Conventional multilevel inverters often suffer from high component count, high switching stress, low voltage gain, and increased cost, limiting their practical application. This paper introduces a high-gain novel topology for multilevel inverters with reduced number of total components per level count, low voltage stress on power conductive devices, and minimizing a cost function, which depends on the number of components, standing voltage on switches and diodes, output voltage levels, and gain. The designed topology, which can be applied in photovoltaic (PV) systems, utilizes only one direct current (DC) input supply and a modular structure with the ability of capacitor's voltage self-balancing. The high gain property and low THD of the proposed topology are two advantages that provide sine output waveform, with no need to a high DC input voltage source. Moreover, generalized topology, consisting of cascaded basic units, has been proposed. A comprehensive method has been proposed to determining the values of DC supplies in this configuration, aiming to minimize redundant switching modes and maximize the voltage levels count. The comparison with some other multilevel inverters confirms the desired performance of the basic version given inverter. A prototype has been also implemented and the experimental results have been obtained to verify the advantages of the proposed 25-level topology.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 1","pages":"64-76"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11471014","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147584896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Review of Optimization Methods for Pole-Shoe Structures in Large-Scale Salient Pole Synchronous Motors","authors":"Pengcheng Ma;Jinxiu Chen;Yiwei Ding","doi":"10.30941/CESTEMS.2026.00009","DOIUrl":"https://doi.org/10.30941/CESTEMS.2026.00009","url":null,"abstract":"Optimizing the rotor pole-shoe structure of large salient pole synchronous motors is critical for improving their performance and efficiency, allowing for enhanced responsiveness to grid demands and adjustments in operating conditions. This paper provides a comprehensive review of various pole-shoe structures for salient pole synchronous motor rotors and their associated optimization techniques. First, it outlines the role of the pole-shoe structure and examines the theoretical theories of key electromagnetic parameters, including the pole-arc coefficient, voltage waveform coefficient, and armature reaction coefficient. Regarding structural design, this paper explores several configurations, including the three-segment arc, five-segment arc, single eccentric pole-arc combined with two chordal surface sections, and asymmetric poles. The effects of these designs on the air-gap magnetic field distribution and voltage waveform are evaluated. In terms of methodology, this paper reviews the application of numerical solutions to electromagnetic field inverse problems and the use of optimization algorithms for electrical machine structural optimization. This study illustrates the application of improved simulated annealing algorithms, tabu search algorithms, and particle swarm optimization algorithms for single-objective optimization of five-segment arc pole-shoe structures. Additionally, this paper discusses the use of vector tabu search and multi-objective quantum evolutionary algorithms for the multi-objective optimization of five-segment arc pole-shoe structures. The study concludes that multi-objective optimization algorithms are underutilized for pole-shoe structure optimization and suggests that multi-objective particle swarm optimization could be more extensively employed for this purpose. Furthermore, the potential application of topology optimization methods for the design of salient-pole synchronous motor rotor magnetic poles is proposed.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"10 1","pages":"28-43"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11470994","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147584927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}