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Keywords = unbalanced electric magnetic force

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20 pages, 4962 KiB  
Article
Unbalanced Magnetic Pull Calculation in Ironless Axial Flux Motors
by Guoqing Zhu and Jian Luo
Energies 2025, 18(9), 2397; https://doi.org/10.3390/en18092397 - 7 May 2025
Viewed by 518
Abstract
Axial flux motors have gained widespread attention in the field of electric vehicles. The stator may exert a unilateral axial force on the dual rotors under uneven air gaps. The unbalanced magnetic pull can influence the production and processing of the motor, leading [...] Read more.
Axial flux motors have gained widespread attention in the field of electric vehicles. The stator may exert a unilateral axial force on the dual rotors under uneven air gaps. The unbalanced magnetic pull can influence the production and processing of the motor, leading to issues such as vibrations, bearing degradation, reduced lifespan, and torque reduction attributed to the bearings. Accurate evaluation of the unilateral magnetic pull can reduce costs associated with bearing protection. For dual-rotor motors, the axial forces of the rotors act in opposite directions with nearly equal magnitudes, resulting in the catastrophic cancellation of unbalanced magnetic pull calculations. A similar phenomenon may occur between coils, introducing computational errors. To avoid these errors, the stator was selected as the computational target for unilateral axial force calculations. The integration domain was defined to encompass the entire air region containing all windings, rather than summing individual force components. This merged integration approach was mathematically validated through the Maxwell stress tensor method. Finally, the obtained stator axial force closely matched the rotor axial force in magnitude, demonstrating the accuracy of the proposed method. Full article
(This article belongs to the Section E: Electric Vehicles)
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21 pages, 5316 KiB  
Article
A Model Predictive Control Strategy with Minimum Model Error Kalman Filter Observer for HMEV-AS
by Ying Zhou, Chenlai Liu, Zhongxing Li and Yi Yu
Energies 2025, 18(6), 1557; https://doi.org/10.3390/en18061557 - 20 Mar 2025
Cited by 1 | Viewed by 350
Abstract
In hub-motor electric vehicles (HMEVs), performance is adversely affected by the mechanical-electromagnetic coupling effect arising from deformations of the air gap in the Permanent Magnet Brushless Direct Current Motor (PM BLDC), which are exacerbated by varying road conditions. In this paper, a Model [...] Read more.
In hub-motor electric vehicles (HMEVs), performance is adversely affected by the mechanical-electromagnetic coupling effect arising from deformations of the air gap in the Permanent Magnet Brushless Direct Current Motor (PM BLDC), which are exacerbated by varying road conditions. In this paper, a Model Predictive Control (MPC) strategy for HMEVs equipped with air suspension (AS) is introduced to enhance ride comfort. Firstly, an 18-degree of freedom (DOF) full-vehicle model incorporating unbalanced electromagnetic forces (UEMFs) induced by motor eccentricities is developed and experimentally validated. Additionally, a Minimum Model Error Extended Kalman Filter (MME-EKF) observer is designed to estimate unmeasurable state variables and account for errors resulting from sprung mass variations. To further improve vehicle performance, the MPC optimization objective is formulated by considering the suspension damping force and dynamic displacement constraints, solving for the optimal suspension force within a rolling time domain. Simulation results demonstrate that the proposed MPC approach significantly improves ride comfort, effectively mitigates coupling effects in hub driving motors, and ensures that suspension dynamic stroke adheres to safety criteria. Comparative analyses indicate that the MPC controller outperforms conventional PID control, achieving substantial reductions of approximately 41.59% in sprung mass vertical acceleration, 14.29% in motor eccentricity, 1.78% in tire dynamic load, 17.65% in roll angular acceleration, and 16.67% in pitch angular acceleration. Full article
(This article belongs to the Section F: Electrical Engineering)
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15 pages, 4772 KiB  
Article
Calculation and Analysis of Unbalanced Magnetic Pull of Rotor under Motor Air Gap Eccentricity Fault
by Rui Zhu, Xin Tong, Qingpeng Han, Keyuan He, Xinrou Wang and Xuechao Wang
Sustainability 2023, 15(11), 8537; https://doi.org/10.3390/su15118537 - 24 May 2023
Cited by 11 | Viewed by 4297
Abstract
Due to various factors such as manufacturing, assembly and operation, the motor air gap will be uneven in the circumferential direction, resulting in the air gap eccentricity having a longer air gap on one side and a shorter air gap on the other [...] Read more.
Due to various factors such as manufacturing, assembly and operation, the motor air gap will be uneven in the circumferential direction, resulting in the air gap eccentricity having a longer air gap on one side and a shorter air gap on the other side, which affects the normal operation and service life of the motor. This paper analyzed and compared the applicability of linear and nonlinear calculation methods of unbalanced magnetic pull. Based on the method of finite element analysis, the unbalanced magnetic pull of motor rotor under static eccentricity, dynamic eccentricity and compound eccentricity faults were calculated, and the influence of eccentricity on unbalanced magnetic pull was compared, respectively. The results showed that when the motor has static eccentricity, the main components of unbalanced magnetic pull on the rotor are zero frequency and twice the electrical frequency. When the motor has dynamic eccentricity, the unbalanced magnetic tension component of the rotor is mainly frequency conversion. When the motor has two faults at the same time, the unbalanced magnetic pull has zero frequency, rotating frequency and double electric frequency components at the same time. With the increase in the relative eccentricity, the frequency components of the unbalanced magnetic pull under the three faults increase. An air gap eccentricity fault widely exists in motor equipment. When the unbalanced magnetic pull increases to a certain extent, the rotor will be pulled towards the stator, causing the occurrence of rub-impact phenomenon, and seriously threatening the safe operation of the system. In this paper, the numerical analysis method and finite meta-computing method were used for the first time to analyze and compare the unbalanced magnetic pull on the rotor of permanent magnet synchronous motor under three kinds of air gap eccentricity faults. The results showed that the characteristic frequency amplitude of the unbalanced magnetic pull calculated by the two methods is relatively close. Therefore, it is of great significance to carry out calculation and analysis of the unbalanced magnetic pull force under the air gap eccentric fault of the motor. Full article
(This article belongs to the Special Issue Sustainable Science and Technologies of Intelligent Manufacturing)
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24 pages, 4851 KiB  
Article
Vertical-Longitudinal Coupling Effect Investigation and System Optimization for a Suspension-In-Wheel-Motor System in Electric Vehicle Applications
by Ze Zhao, Lei Zhang, Jianyang Wu, Liang Gu and Shaohua Li
Sustainability 2023, 15(5), 4168; https://doi.org/10.3390/su15054168 - 25 Feb 2023
Cited by 4 | Viewed by 2383
Abstract
In-wheel-motor-drive electric vehicles have attracted enormous attention due to its potentials of improving vehicle performance and safety. Road surface roughness results in forced vibration of in-wheel-motor (IWM) and thus aggravates the unbalanced electric magnetic force (UEMF) between its rotor and stator. This can [...] Read more.
In-wheel-motor-drive electric vehicles have attracted enormous attention due to its potentials of improving vehicle performance and safety. Road surface roughness results in forced vibration of in-wheel-motor (IWM) and thus aggravates the unbalanced electric magnetic force (UEMF) between its rotor and stator. This can further compromise vertical and longitudinal vehicle dynamics. This paper presents a comprehensive study to reveal the coupled vertical–longitudinal effect on suspension-in-wheel-motor systems (SIWMS) along with a viable optimization procedure to improve ride comfort and handling performance. First, a UEMF model is established to analyze the mechanical–electrical–magnetic coupling relationship inside an IWM. Then a road–tire–ring force (RTR) model that can capture the transient tire–road contact patch and tire belt deformation is established to accurately describe the road–tire and tire–rotor forces. The UEMF and the RTRF model are incorporated into the quarter-SIWMS model to investigate the coupled vertical–longitudinal vehicle dynamics. Through simulation studies, a comprehensive evaluation system is put forward to quantitatively assess the effects during braking maneuvers under various road conditions. The key parameters of the SIWMS are optimized via a multi-optimization method to reduce the adverse impact of UEMF. Finally, the multi-optimization method is validated in a virtual prototype which contains a high-fidelity multi-body model. The results show that the longitudinal acceleration fluctuation rate and the slip ratio signal-to-noise ratio are reduced by 5.07% and 6.13%, respectively, while the UEMF in the vertical and longitudinal directions varies from 22.2% to 34.7%, respectively, and is reduced after optimization. Thus, the negative coupling effects of UEMF are minimized while improving the ride comfort and handling performance. Full article
(This article belongs to the Topic Advanced Electric Vehicle Technology)
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23 pages, 8317 KiB  
Article
An Integrated Vibration Elimination System with Mechanical-Electrical-Magnetic Coupling Effects for In-Wheel-Motor-Driven Electric Vehicles
by Ze Zhao, Liang Gu, Jianyang Wu, Xinyang Zhang and Haixu Yang
Electronics 2023, 12(5), 1117; https://doi.org/10.3390/electronics12051117 - 24 Feb 2023
Cited by 8 | Viewed by 2465
Abstract
This study aims to improve the vehicle vertical dynamics performance in the sprung and unsprung state for in-wheel-motor-driven electric vehicles (IWMD EVs) while considering the unbalanced electric magnetic force effects. An integrated vibration elimination system (IVES) is developed, containing a dynamic vibration-absorbing structure [...] Read more.
This study aims to improve the vehicle vertical dynamics performance in the sprung and unsprung state for in-wheel-motor-driven electric vehicles (IWMD EVs) while considering the unbalanced electric magnetic force effects. An integrated vibration elimination system (IVES) is developed, containing a dynamic vibration-absorbing structure between the IWM and the suspension. It also includes an active suspension system based on a delay-dependent H controller. Further, a novel frequency-compatible tire (FCT) model is constructed to improve IVES accuracy. The mechanical-electrical-magnetic coupling effects of IWMD EVs are theoretically analyzed. A virtual prototype for the IVES is created by combining the CATIA, ADAMS, and MatLab/Simulink, resulting in a high-fidelity multi-body model, validating the IVES accuracy and practicability. Simulations for the IVES considered three different suspension structure types and time delay considerations were performed. Analyses in frequency and time domains for the simulation results have shown that the root mean square of sprung mass acceleration and the eccentricity are significantly reduced via the IVES, indicating an improvement in ride comfort and IWM vibration suppression. Full article
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17 pages, 1945 KiB  
Article
Optimal Design of an Inductive MHD Electric Generator
by Sara Carcangiu, Alessandra Fanni and Augusto Montisci
Sustainability 2022, 14(24), 16457; https://doi.org/10.3390/su142416457 - 8 Dec 2022
Cited by 4 | Viewed by 3147
Abstract
In this paper, the problem of optimizing the design of an inductive Magneto-Hydro-Dynamic (MHD) electric generator is formalized as a multi-objective optimization problem where the conflicting objectives consist of maximizing the output power while minimizing the hydraulic losses and the mass of the [...] Read more.
In this paper, the problem of optimizing the design of an inductive Magneto-Hydro-Dynamic (MHD) electric generator is formalized as a multi-objective optimization problem where the conflicting objectives consist of maximizing the output power while minimizing the hydraulic losses and the mass of the apparatus. In the proposal, the working fluid is ionized with periodical pulsed discharges and the resulting neutral plasma is unbalanced by means of an intense DC electrical field. The gas is thus split into two charged streams, which induce an electromotive force into a magnetically coupled coil. The resulting generator layout does not require the use of superconducting coils and allows you to manage the issues related to the conductivity of the gas and the corrosion of the electrodes, which are typical limits of the MHD generators. A tailored multi-objective optimization algorithm, based on the Tabu Search meta-heuristics, has been implemented, which returns a set of Pareto optimal solutions from which it is possible to choose the optimal solution according to further applicative or performance constraints. Full article
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29 pages, 6090 KiB  
Article
Fault-Ride-Through Approach for Grid-Tied Smart Transformers without Local Energy Storage
by Justino Rodrigues, Carlos Moreira and João Peças Lopes
Energies 2021, 14(18), 5622; https://doi.org/10.3390/en14185622 - 7 Sep 2021
Cited by 5 | Viewed by 2204
Abstract
The Smart Transformer (ST) is being envisioned as the possible backbone of future distribution grids given the enhanced controllability it provides. Moreover, the ST offers DC-link connectivity, making it an attractive solution for the deployment of hybrid AC/DC distribution grids which offer important [...] Read more.
The Smart Transformer (ST) is being envisioned as the possible backbone of future distribution grids given the enhanced controllability it provides. Moreover, the ST offers DC-link connectivity, making it an attractive solution for the deployment of hybrid AC/DC distribution grids which offer important advantages for the deployment of Renewable Energy Sources, Energy Storage Systems (ESSs) and Electric Vehicles. However, compared to traditional low-frequency magnetic transformers, the ST is inherently more vulnerable to fault disturbances which may force the ST to disconnect in order to protect its power electronic converters, posing important challenges to the hybrid AC/DC grid connected to it. This paper proposes a Fault-Ride-Through (FRT) strategy suited for grid-tied ST with no locally available ESS, which exploits a dump-load and the sensitivity of the hybrid AC/DC distribution grid’s power to voltage and frequency to provide enhanced control to the ST in order to handle AC-side voltage sags. The proposed FRT strategy can exploit all the hybrid AC/DC distribution grid (including the MV DC sub-network) and existing controllable DER resources, providing FRT against balanced and unbalanced faults in the upstream AC grid. The proposed strategy is demonstrated in this paper through computational simulation. Full article
(This article belongs to the Special Issue Innovative Solutions for Modern Distribution Networks)
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17 pages, 7631 KiB  
Article
High-Efficient Brushless Wound Rotor Synchronous Machine Topology Based on Sub-Harmonic Field-Excitation Technique
by Syed Sabir Hussain Bukhari, Qasim Ali, Jesús Doval-Gandoy and Jong-Suk Ro
Energies 2021, 14(15), 4427; https://doi.org/10.3390/en14154427 - 22 Jul 2021
Cited by 17 | Viewed by 3366
Abstract
This paper presents a new high-efficient three-phase brushless wound rotor synchronous machine (BL-WRSM) based on a sub-harmonic field excitation technique. In the proposed machine topology, the stator is equipped with two different three-phase windings: (1) main armature winding, and (2) additional armature winding. [...] Read more.
This paper presents a new high-efficient three-phase brushless wound rotor synchronous machine (BL-WRSM) based on a sub-harmonic field excitation technique. In the proposed machine topology, the stator is equipped with two different three-phase windings: (1) main armature winding, and (2) additional armature winding. The main armature winding is based on a 4-pole winding configuration, whereas the additional armature winding is based on a 2-pole winding configuration. Both windings are supplied current from two different inverters, i.e., inverter-1, inverter-2, and simultaneously. Inverter-1 provides the regular input current to the main armature winding, whereas inverter-2 provides a three-phase current of low magnitude to the 2-pole additional armature winding. This generates an additional sub-harmonic component of MMF in the airgap beside the fundamental MMF. On the other side, the rotor is equipped with (1) harmonic, and (2) field windings. These windings are electrically coupled via a rectifier. The fundamental component of MMF produces the main rotating magnetic field, whereas the sub-harmonic MMF gets induced in the harmonic winding to produce harmonic current. This current is rectified to give DC to the rotor field winding to attain brushless operation. To authenticate the operation and analyze its performance, the proposed BL-WRSM topology is supported using 2-D finite element analysis (FEA) in JMAG-Designer. Later on, the performance of the proposed brushless topology is compared with the customary BL-WRSM topology to verify its high efficiency, high output torque, low torque ripple, and low unbalanced radial force on the rotor. Full article
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11 pages, 9115 KiB  
Article
Experimental and Comparative Study of Rotor Vibrations of Permanent Magnet Machines with Two Different Fractional Pole/Slot Combinations
by Tae-Kyoung Bang, Kyung-Hun Shin, Jeong-In Lee, Hoon-Ki Lee, Han-Wook Cho and Jang-Young Choi
Appl. Sci. 2020, 10(24), 8792; https://doi.org/10.3390/app10248792 - 9 Dec 2020
Cited by 3 | Viewed by 3288
Abstract
This study deals with the noise, vibration, and harshness (NVH) characteristic analysis of permanent magnet synchronous motors (PMSMs) for electrical machines, such as electrically driven tools that are used in industries. An improved NVH design is needed for application to industrial tools. In [...] Read more.
This study deals with the noise, vibration, and harshness (NVH) characteristic analysis of permanent magnet synchronous motors (PMSMs) for electrical machines, such as electrically driven tools that are used in industries. An improved NVH design is needed for application to industrial tools. In general, the electromagnetic NVH characteristics of PMSMs are classified into electromagnetic excitation sources, such as total harmonic distortion of EMF, torque pulsation, magnetic pull force, and unbalanced magnetic force (UMF). This study compares the vibration and noise generated by fractional pole/slot combinations. In PMSMs with fractional pole/slot combinations, UMF is an important NVH source. PMSMs generate UMF because of armature reaction fields based on the pole/slot combinations and harmonics of magnetic flux density. UMF was derived using the finite element method, and the rotor vibration analysis was performed using electromagnetic mechanical coupling analysis. The analysis results and the effect of electromagnetic excitation characteristics on the rotor vibration of the PMSMs were compared and analyzed. Full article
(This article belongs to the Special Issue Modeling, Design and Control of Electric Machines)
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15 pages, 5481 KiB  
Article
Electromagnetic Vibration Analysis and Slot–Pole Structural Optimization for a Novel Integrated Permanent Magnet In-Wheel Motor
by Qiang Wang, Pingping Zhao, Xianbin Du, Fen Lin and Xu Li
Energies 2020, 13(13), 3488; https://doi.org/10.3390/en13133488 - 6 Jul 2020
Cited by 8 | Viewed by 3108
Abstract
This paper presents a novel integrated permanent magnet (PM) in-wheel motor (IWM) driving system for electric vehicles (EVs), in order to overcome the disadvantages of electromagnetic vibration and cogging torque in the topology scheme, on the basis of maintaining high output torque. Firstly, [...] Read more.
This paper presents a novel integrated permanent magnet (PM) in-wheel motor (IWM) driving system for electric vehicles (EVs), in order to overcome the disadvantages of electromagnetic vibration and cogging torque in the topology scheme, on the basis of maintaining high output torque. Firstly, the transient magnetic field of the integrated PM motor is analyzed using the improved analytical subdomain model and finite element (FE) model. The harmonic component of magnetic force density (MFD) is obtained with no-load condition. Furthermore, the vertical dynamic model for the dynamic vibration absorber is established to investigate the influence of the magnetic force harmonic on the vibration response of the stator and rotor. On this basis, the multi-objective optimization design of the pole–slot structure parameters is carried out by using the adaptive weighted particle swarm optimization (AWPSO) algorithm. Finally, the optimization results are compared and verified by FE analysis. The investigation shows that the unbalanced magnetic force and cogging torque is significantly reduced by the adjustment of the pole-arc coefficient, PM thickness, stator slot width and slot opening width. Full article
(This article belongs to the Section E: Electric Vehicles)
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21 pages, 11385 KiB  
Article
Two-Dimensional Exact Subdomain Technique of Switched Reluctance Machines with Sinusoidal Current Excitation
by Mohammed Ben Yahia, Kamel Boughrara, Frédéric Dubas, Lazhar Roubache and Rachid Ibtiouen
Math. Comput. Appl. 2018, 23(4), 59; https://doi.org/10.3390/mca23040059 - 11 Oct 2018
Cited by 11 | Viewed by 3811
Abstract
This paper presents a two-dimensional (2D) exact subdomain technique in polar coordinates considering the iron relative permeability in 6/4 switched reluctance machines (SRM) supplied by sinusoidal waveform of current (aka, variable flux reluctance machines). In non-periodic regions (e.g., rotor and/or stator slots/teeth), magnetostatic [...] Read more.
This paper presents a two-dimensional (2D) exact subdomain technique in polar coordinates considering the iron relative permeability in 6/4 switched reluctance machines (SRM) supplied by sinusoidal waveform of current (aka, variable flux reluctance machines). In non-periodic regions (e.g., rotor and/or stator slots/teeth), magnetostatic Maxwell’s equations are solved considering non-homogeneous Neumann boundary conditions (BCs). The general solutions of magnetic vector potential in all subdomains are obtained by applying the interface conditions (ICs) in both directions (i.e., r- and θ-edges ICs). The global saturation effect is taken into account, with a constant magnetic permeability corresponding to the linear zone of the nonlinear B(H) curve. In this investigation, the magnetic flux density distribution inside the electrical machine, the static/dynamic electromagnetic torques, the magnetic flux linkage, the self-/mutual inductances, the magnetic pressures, and the unbalanced magnetic forces (UMFs) have been calculated for 6/4 SRM with two various non-overlapping (or concentrated) windings. One of the case studies is a M1 with a non-overlapping all teeth wound winding (double-layer winding with left and right layer) and the other is a M2 with a non-overlapping alternate teeth wound winding (single-layer winding). It is important to note that the developed semi-analytical model based on the 2D exact subdomain technique is also valid for any number of slot/pole combinations and for non-overlapping teeth wound windings with a single/double layer. Finally, the semi-analytical results have been performed for different values of iron core relative permeability (viz., 100 and 800), and compared with those obtained by the 2D finite-element method (FEM). The comparisons with FEM show good results for the proposed approach. Full article
(This article belongs to the Special Issue Mathematical Models for the Design of Electrical Machines)
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20 pages, 4506 KiB  
Article
Analysis on the Amplitude and Frequency Characteristics of the Rotor Unbalanced Magnetic Pull of a Multi-Pole Synchronous Generator with Inter-Turn Short Circuit of Field Windings
by Guangtao Zhang, Junyong Wu and Liangliang Hao
Energies 2018, 11(1), 60; https://doi.org/10.3390/en11010060 - 1 Jan 2018
Cited by 11 | Viewed by 4937
Abstract
Inter-turn short circuit of field windings (ISCFW) is a common generator fault which can result in serious safety accidents for power systems, if the fault is not eliminated in time. Taking advantage of the electrical and mechanical characteristics of the generator after a [...] Read more.
Inter-turn short circuit of field windings (ISCFW) is a common generator fault which can result in serious safety accidents for power systems, if the fault is not eliminated in time. Taking advantage of the electrical and mechanical characteristics of the generator after a fault as a fault criterion is a new idea for fault monitoring, so finding out the frequency and amplitude frequency characteristics of rotor unbalanced magnetic pull (UMP)—the vibration excitation source of the fault—is the basis and key of the research. Taking a six-pole generator as an example, the effects of harmonic magnetic motive force (MMF) interaction on rotor UMP, as well as the frequency characteristics of rotor UMP after generator faults in different stator windings, are obtained based on the analysis of the air-gap MMF of the generator after a fault, and the results of theoretical analysis are verified by simulation. Based on the above results, the simulation calculation on rotor UMP of generators with three stator winding forms under different operating conditions has been achieved, to get the relation between rotor UMP amplitude and active power and field current, and to find out the mechanism of rotor UMP amplitude change along with operating conditions and effect of stator winding forms on UMP amplitude by theoretical analysis. The conclusions are of important significance for studying fault mechanical characteristics of generators and lay a foundation for online monitoring on ISCFW by integrating mechanical and electrical information. Full article
(This article belongs to the Section I: Energy Fundamentals and Conversion)
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19 pages, 6579 KiB  
Article
Fast Calculation Model and Theoretical Analysis of Rotor Unbalanced Magnetic Pull for Inter-Turn Short Circuit of Field Windings of Non-Salient Pole Generators
by Guangtao Zhang, Junyong Wu and Liangliang Hao
Energies 2017, 10(5), 732; https://doi.org/10.3390/en10050732 - 20 May 2017
Cited by 14 | Viewed by 7217
Abstract
Inter-turn short circuit of field windings (ISCFW) may cause the field current of a generator to increase, output reactive power to decrease, and unit vibration to intensify, seriously affecting its safe and stable operation. Full integration of mechanical and electrical characteristics can improve [...] Read more.
Inter-turn short circuit of field windings (ISCFW) may cause the field current of a generator to increase, output reactive power to decrease, and unit vibration to intensify, seriously affecting its safe and stable operation. Full integration of mechanical and electrical characteristics can improve the sensitivity of online monitoring, and detect the early embryonic period fault of small turns. This paper studies the calculations and variations of unbalanced magnetic pull (UMP), of which the excitation source of rotor vibration is the basis and key to online fault monitoring. In grid load operation, ISCFW are first calculated with the multi-loop method, so as to obtain the numerical solutions of the stator and the rotor currents during the fault. Next, the air-gap magnetic field of the ISCFW is analyzed according to the actual composition modes of the motor loops in the fault, so as to obtain the analytic expressions of the air-gap magnetic motive force (MMF) and magnetic density. The UMP of the rotor is obtained by solving the integral of the Maxwell stress. The correctness of the electric quantity calculation is verified by the ISCFW experiment, conducted in a one pair-pole non-salient pole model machine. On this basis, comparing the simulation analysis with the calculation results of the model in this paper not only verifies the accuracy of the electromagnetic force calculation, but also proves that the latter has the advantages of a short time consumption and high efficiency. Finally, the influencing factors and variation law of UMP are analyzed by means of an analytic model. This develops a base for the online monitoring of ISCFW with the integration of mechanical and electrical information. Full article
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6 pages, 2474 KiB  
Article
Abnormal Electromagnetic Noise of Motors depending on Fixing Methods of Permanent Magnets
by Myunggyu Kim and Hyunsu Kim
World Electr. Veh. J. 2015, 7(2), 195-200; https://doi.org/10.3390/wevj7020195 - 26 Jun 2015
Cited by 2 | Viewed by 2230
Abstract
Abnormal electromagnetic noise of traction motor in hybrid electric vehicle (HEV) occurred after the endurance test is experimentally investigated. Theoretical model explains that the abnormal components, which are ±1 orders of the number of slots, can be sourced from an unbalanced rotor. Experimental [...] Read more.
Abnormal electromagnetic noise of traction motor in hybrid electric vehicle (HEV) occurred after the endurance test is experimentally investigated. Theoretical model explains that the abnormal components, which are ±1 orders of the number of slots, can be sourced from an unbalanced rotor. Experimental approach confirms that the abnormal noise is mainly from the rotor. Since there are no variations in the strength of the magnet flux, the vibration of the magnets is strongly believed as the main reason of the abnormal noise. Finally, the magnetic fixing method is changed from bond to mold, and the improvement of the noise is demonstrated. Full article
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