Frontier
High-Fidelity Lumped-Parameter Thermal Models for Assessing Cooling Techniques of PMSMs in EV Applications
高精度集中参数热模型:电动汽车应用的永磁同步电机冷却技术评估
Dawei Liang; Zi Qiang Zhu; Ankan Dey
D. Liang, Z. Q. Zhu and A. Dey, "High-Fidelity Lumped-Parameter Thermal Models for Assessing Cooling Techniques of PMSMs in EV Applications," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 1-14, March 2025, doi: 10.30941/CESTEMS.2025.00001.
Abstract—This paper presents a high-fidelity lumped-parameter (LP) thermal model (HF-LPTM) for permanent magnet synchronous machines (PMSMs) in electric vehicle (EV) applications, where various cooling techniques are considered, including frame forced air/liquid cooling, oil jet cooling for end-winding, and rotor shaft cooling. To address the temperature misestimation in the LP thermal modelling due to assumptions of concentrated loss input and uniform heat flows, the developed HF-LPTM introduces two compensation thermal resistances for the winding and PM components, which are analytically derived from the multidimensional heat transfer equations and are robust against different load/thermal conditions. As validated by the finite element analysis method and experiments, the conventional LPTMs exhibit significant winding temperature deviations, while the proposed HF-LPTM can accurately predict both the midpoint and average temperatures. The developed HF-LPTM is further used to assess the effectiveness of various cooling techniques under different scenarios, i.e., steady-state thermal states under the rated load condition, and transient temperature profiles under city, freeway, and hybrid (city + freeway) driving cycles. Results indicate that no single cooling technique can maintain both winding and PM temperatures within safety limits. The combination of frame liquid cooling and oil jet cooling for end winding can sufficiently mitigate PMSM thermal stress in EV applications.
■ ■
Analysis of Radial Force, Vibration, and Noise in Low-Speed, High-Torque Density Spoke-Type PMSMs with Symmetric and Asymmetric Assisted Poles Designs
具有对称和非对称辅助极设计的低速、高扭矩密度辐条型永磁同步电机的径向力、振动和噪声分析
Sayyed Haleem Shah; Yun-Chong Wang; Dan Shi; Jian-Xin Shen
S. H. Shah, Y. -C. Wang, D. Shi and J. -X. Shen, "Analysis of Radial Force, Vibration, and Noise in Low-Speed, High-Torque Density Spoke-Type PMSMs with Symmetric and Asymmetric Assisted Poles Designs," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 15-25, March 2025, doi: 10.30941/CESTEMS.2025.00003.
Abstract—This article investigates the radial electromagnetic force, vibration, and noise phenomenon in a low-speed, high-torque density spoke-type permanent magnet synchronous machine (ST-PMSM) designed with assisted poles having symmetric and asymmetric topologies. Firstly, an analytical expression for the machine radial electromagnetic force (REMF) is derived to quickly estimate the REMF characteristics for the ST-PMSM with assisted poles having symmetric and asymmetric topologies. The 2D-Fourier decomposition method is applied to investigate the radial electromagnetic force harmonics (REMFHs). Secondly, Finite element (FE) models are designed for the machine structural analysis. Subsequently, the FE models and modal analysis are explored for different design cases of the analyzed machine. Lastly, vibration and noise behavior are investigated using an FE approach for the machine designs under symmetric and asymmetric assisted poles topologies. The findings indicate an increase in the richness of REMFHs, alongside a decrease in both the fundamental frequency and the lowest nonzero order of REMF, attributed to the presence of asymmetric assisted poles. Consequently, it is investigated that while considering the vibration and noise response in ST-PMSMs designed with asymmetric assisted poles topologies, it is essential to thoroughly account for induced nonzero low-order harmonics and their optimization for better vibration and noise performance.
■ ■
Regular Paper
Moving Towards the Reliability-Oriented Design of Hairpin Winding for EV Traction Machines Driven by SiC Inverter
面向可靠性的SiC逆变器驱动电动汽车牵引机发夹绕组设计
Xiaowei Ju; Yue Zhang; Zhiwei Xue; Yuan Cheng; Shumei Cui
X. Ju, Y. Zhang, Z. Xue, Y. Cheng and S. Cui, "Moving Towards the Reliability-Oriented Design of Hairpin Winding for EV Traction Machines Driven by SiC Inverter," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 26-35, March 2025, doi: 10.30941/CESTEMS.2025.00005.
Abstract—With the development of high-frequency and high-voltage traction machines (TM) incorporating hairpin windings (HW) and SiC inverters for electric vehicles (EV), both the interturn voltage stress and temperature within HW are rising, increasing the risk of partial discharge (PD), and presenting significant challenges to insulation safety. Therefore, this paper addresses this issue and proposes potential solutions. Firstly, the paper examines an 8-pole, 48-slot, 6-layer HW TM to highlight the unique characteristics of this winding structure, and explains the uneven distribution of interturn voltage stress and temperature. Subsequently, a high-frequency equivalent circuit model of the HW TM prototype is developed. The error of simulation and experiment is only 5.7 %, which proves the accuracy of the model. Then, an improved HW scheme is proposed to lower the maximum voltage stress by 29.3 %. Furthermore, the temperature distribution of HW TM is analyzed to facilitate a detailed examination of the impact of temperature on insulation PD. Finally, the partial discharge inception voltage (PDIV) of interturn insulation, considering temperature effects, is calculated and verified through experiment. The paper proposes a reliability-oriented design method and process for HW TM. It demonstrates that the reliability-oriented design can achieve PD-free performance in the design stage of HW.
■ ■
Design and Parametric Optimization of a Double-Sided Linear Induction Motor for Hyperloop Pod
用于Hyperloop吊舱的双面直线感应电机设计与参数优化
Bahaddin Goksun; Ismet Sen; Musap Kuzucu; Bati Eren Ergun; Ilhan Kocaarslan; Mehmet Onur Gulbahce
B. Goksun, I. Sen, M. Kuzucu, B. E. Ergun, I. Kocaarslan and M. O. Gulbahce, "Design and Parametric Optimization of a Double-Sided Linear Induction Motor for Hyperloop Pod," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 36-45, March 2025, doi: 10.30941/CESTEMS.2025.00009.
Abstract—The hyperloop idea, which is one of the most ecofriendly, low-carbon emissions, and fossil fuel-efficient modes of transportation, has recently become quite popular. In this study, a double-sided linear induction motor (LIM) with 500 W of output power, 60 N of thrust force and 200 V/38.58 Hz of supply voltage was designed to be used in hyperloop development competition hosted by the scientific and technological research council of turkey (TÜBİTAK) rail transportation technologies institute (RUTE). In contrast to the studies in the literature, concentrated winding is preferred instead of distributed winding due to mechanical constraints. The electromagnetic design of LIM, whose mechanical and electrical requirements were determined considering the hyperloop development competition, was carried out by following certain steps. Then, the designed model was simulated and analyzed by finite element method (FEM), and the necessary optimizations have been performed to improve the motor characteristics. By examining the final model, the applicability of the concentrated winding type LIM for hyperloop technology has been investigated. Besides, the effects of primary material, railway material, and mechanical air-gap length on LIM performance were also investigated. In the practical phase of the study, the designed LIM has been prototyped and tested. The validation of the experimental results was achieved through good agreement with the finite element analysis results.
■ ■
A Comprehensive Review of Torque and Speed Control Strategies for Switched Reluctance Motor Drives
开关磁阻电机驱动器转矩和速度控制策略综述
Sreeram K; Preetha P K; Javier Rodríguez-García; Carlos Álvarez-Bel
S. K, P. P K, J. Rodríguez-García and C. Álvarez-Bel, "A Comprehensive Review of Torque and Speed Control Strategies for Switched Reluctance Motor Drives," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 46-75, March 2025, doi: 10.30941/CESTEMS.2025.00006.
Abstract—Switched Reluctance Motors (SRMs), outfitted with rugged construction, good speed range, high torque density, and rare earth-free nature that outweigh induction motors (IM) and permanent magnet synchronous motor (PMSM), afford a broad range of applications in the domain of electric vehicles (EVs). Standard copper magnetic wire and low-carbon steel laminations are used to construct SRMs, which give them high efficiency in the range of 85–95%. Despite SRM's desirable features over traditional motor-speed drives, high torque ripples and radial distortions constrain their deployment in EVs. Precise rotor position is imperative for effective management of the speed and torque of SRMs. This paper provides an illustrative compendium on review of the torque-speed control and ripple mitigation techniques using design enhancements and control methods for SRM drives for EV applications. The various schemes were evaluated on their performance metrics-operational speed range, control complexity, practical realization, need for pre-stored parameters (lookup tables of current, inductance and torque profiles) and motor controller memory requirements. The findings provide valuable insights into balancing the gains and tradeoffs associated with EV applications. Furthermore, they pinpoint opportunities for enhancement by analyzing the cost and technical aspects of different SRM controllers.
■ ■
Model-Free Predictive Control of Motor Drives: A Review
电机驱动的无模型预测控制综述
Chenhui Zhou; Yongchang Zhang; Haitao Yang
C. Zhou, Y. Zhang and H. Yang, "Model-Free Predictive Control of Motor Drives: A Review," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 76-90, March 2025, doi: 10.30941/CESTEMS.2025.00002.
Abstract—Model predictive control (MPC) has been deemed as an attractive control method in motor drives by virtue of its simple structure, convenient multi-objective optimization, and satisfactory dynamic performance. However, the strong reliance on mathematical models seriously restrains its practical application. Therefore, improving the robustness of MPC has attained significant attentions in the last two decades, followed by which, model-free predictive control (MFPC) comes into existence. This article aims to reveal the current state of MFPC strategies for motor drives and give the categorization from the perspective of implementation. Based on this review, the principles of the reported MFPC strategies are introduced in detail, as well as the challenges encountered in technology realization. In addition, some of typical and important concepts are experimentally validated via case studies to evaluate the performance and highlight their features. Finally, the future trends of MFPC are discussed based on the current state and reported developments.
■ ■
Speed Harmonic Based Saturation Free Inductance Modeling and Estimation of Interior PMSM Using Measurements Under One Load Condition
单负载条件下基于速度谐波的内置永磁同步电机饱和自由电感建模与估计
Guodong Feng; Yuting Lu; Zhe Tong; Beichen Ding; Guishan Yan; Chunyan Lai
G. Feng, Y. Lu, Z. Tong, B. Ding, G. Yan and C. Lai, "Speed Harmonic Based Saturation Free Inductance Modeling and Estimation of Interior PMSM Using Measurements Under One Load Condition," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 91-99, March 2025, doi: 10.30941/CESTEMS.2025.00010.
Abstract—For permanent magnet synchronous machines (PMSMs), accurate inductance is critical for control design and condition monitoring. Owing to magnetic saturation, existing methods require nonlinear saturation model and measurements from multiple load/current conditions, and the estimation is relying on the accuracy of saturation model and other machine parameters in the model. Speed harmonic produced by harmonic currents is inductance-dependent, and thus this paper explores the use of magnitude and phase angle of the speed harmonic for accurate inductance estimation. Two estimation models are built based on either the magnitude or phase angle, and the inductances can be from d-axis voltage and the magnitude or phase angle, in which the filter influence in harmonic extraction is considered to ensure the estimation performance. The inductances can be estimated from the measurements under one load condition, which is free of saturation model. Moreover, the inductance estimation is robust to the change of other machine parameters. The proposed approach can effectively improve estimation accuracy especially under the condition with low current magnitude. Experiments and comparisons are conducted on a test PMSM to validate the proposed approach.
■ ■
An Improved Feedforward Control Strategy to Promote the Rapidity of PMSM Servo System and Reduce Overshoot Oscillation
一种提高永磁同步电机伺服系统速度并减小超调振荡的改进前馈控制策略
Wentao Zhang; Yan Zhang; Yongxiang Xu; Jibin Zou
W. Zhang, Y. Zhang, Y. Xu and J. Zou, "An Improved Feedforward Control Strategy to Promote the Rapidity of PMSM Servo System and Reduce Overshoot Oscillation," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 100-109, March 2025, doi: 10.30941/CESTEMS.2025.00008.
Abstract—Under the condition of large inertia load, the stability of the servo system is more sensitive to the response speed and more likely to produce overshoot oscillations. In order to realize the requirements of high-precision and fast-response control of permanent magnet synchronous motor (PMSM) under large inertia load, an improved feedforward control strategy based on position impulse compensation and PD iterative algorithm is proposed to improve the response speed of the PMSM servo system and reduce the overshoot oscillation. This paper analyzes the mathematical models of the speed servo system and position servo system of the PMSM, calculates position overshoot impulse of the PMSM servo system, and improves the traditional feedforward control strategy to reversely compensate when the position is about to overshoot. Moreover, in order to further reduce the position overshoot, the PD iterative control algorithm is superimposed without increasing the complexity of the algorithm. The input signal is continuously corrected through multiple runs to achieve a smoother response control. The effectiveness of the proposed feedforward control strategy is verified by simulation and experiment.
■ ■
PLL Frequency Stability Enhancement Under Weak Grid Considering Reactive Current Support
弱电网下考虑无功电流支持的锁相环频率稳定性增强方法
Bin Hu; Ling Zhan; Heng Nian; Donglian Qi
B. Hu, L. Zhan, H. Nian and D. Qi, "PLL Frequency Stability Enhancement Under Weak Grid Considering Reactive Current Support," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 110-114, March 2025, doi: 10.30941/CESTEMS.2025.00007.
Abstract—The phase-locked loop (PLL) plays an essential role for synchronizing renewable power generation to the grid. However, as per the grid-code compliance for reactive current support, the PLL output frequency fluctuates significantly and exceeds the limitation, which seriously threaten the safe supply of electricity. In this paper, the underlying theoretical mechanism and dominant force behind the maximum PLL frequency deviation are revealed. Accordingly, two feasible approaches are proposed to enhance the PLL frequency stability with validations in experimental results.
■ ■
Recent Development of Aircraft Electric Propulsion System: A Technical Review
飞机电推进系统的最新发展技术综述
Wei Chen; Yexin Yan; Yang Qi; Ming Huang; Weilin Li
W. Chen, Y. Yan, Y. Qi, M. Huang and W. Li, "Recent Development of Aircraft Electric Propulsion System: A Technical Review," in CES Transactions on Electrical Machines and Systems, vol. 9, no. 1, pp. 115-130, March 2025, doi: 10.30941/CESTEMS.2025.00004.
Abstract—The technology of electric propulsion aircraft (EPA) represents an important direction and an advanced stage in the development of aviation electrification. It is a key pathway for green development in aviation industry and can significantly enhance the energy efficiency of aircraft propulsion system. Electric motor is the most critical electromechanical energy conversion component in an aircraft electric propulsion system (EPS). High-performance electric motors, power electronic converters and EPS control form the foundation of the EPA. This paper provides an overview of the characteristics of electric motors for EPA, analyzes the inverter topologies of EPSs, and reviews ongoing EPA projects. The article highlights the latest advancements in three types of motors: superconducting motors (SCMs), permanent magnet synchronous motors (PMSMs), and induction motors (IMs). It summarizes the control system architectures of current EPA initiatives and, building on this foundation, proposes future research directions for EPSs. These include cutting-edge areas such as high-performance motors and advanced manufacturing technologies, GaN- or SiC- based inverter integration and innovation, electric propulsion control systems, and optimization of wiring systems.
■ ■
《中国电工技术学会电机与系统学报(英文)》(CES TEMS)是中国电工技术学会和中国科学院电工研究所共同主办、IEEE PELS学会技术支持的英文学术期刊。期刊发表国内外有关高性能电机系统、电机驱动、电力电子、可再生能源系统、电气化交通等研发及应用领域中原创、前沿学术论文。中国工程院院士马伟明担任主编,IEEE的执委Don Tan博士为国际主编。目前已被ESCI、EI、Scopus、 Inspec、Google scholar、IEEE Xplore、中国科学引文数据库(CSCD) 核心版、DOAJ、CSTPCD、知网、万方、维普等数据库收录。
中国电工技术学会
新媒体平台
学会官方微信
电工技术学报
CES电气
学会官方B站
CES TEMS
今日头条号
学会科普微信
抖音号
特别声明:以上内容(如有图片或视频亦包括在内)为自媒体平台“网易号”用户上传并发布,本平台仅提供信息存储服务。
Notice: The content above (including the pictures and videos if any) is uploaded and posted by a user of NetEase Hao, which is a social media platform and only provides information storage services.