Scheduled System Maintenance:
Some services will be unavailable Sunday, March 29th through Monday, March 30th. We apologize for the inconvenience.
By Topic

Magnetics, IEEE Transactions on

Issue 8  Part 2 • Date Aug. 2013

Filter Results

Displaying Results 1 - 25 of 34
  • [Front cover]

    Publication Year: 2013 , Page(s): C1
    Save to Project icon | Request Permissions | PDF file iconPDF (183 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Magnetics publication information

    Publication Year: 2013 , Page(s): C2
    Save to Project icon | Request Permissions | PDF file iconPDF (196 KB)  
    Freely Available from IEEE
  • Table of contents

    Publication Year: 2013 , Page(s): 4745 - 4747
    Save to Project icon | Request Permissions | PDF file iconPDF (167 KB)  
    Freely Available from IEEE
  • In Memoriam

    Publication Year: 2013 , Page(s): 4748
    Save to Project icon | Request Permissions | PDF file iconPDF (342 KB) |  | HTML iconHTML  
    Freely Available from IEEE
  • Fast and Accurate Calculation of the Demagnetization Tensor for Systems With Periodic Boundary Conditions

    Publication Year: 2013 , Page(s): 4749 - 4755
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1639 KB) |  | HTML iconHTML  

    In micromagnetic simulations, the magnetization in one simulation cell is acted upon by the demagnetization field that is generated by all simulation cells. In simulations with periodic boundary conditions, this leads to an infinite number of interactions that have to be taken into account. A method is presented that allows for an accurate calculation of the demagnetization tensor with one and two-dimensional periodic boundary conditions using a small amount of computation time. The method has been implemented in a micromagnetic simulation tool. For a reasonable accuracy and two-dimensional periodic boundary conditions the presented method is about six orders of magnitude faster than the straightforward method in which all cells beyond a certain distance are neglected. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Dependences of Specific Loss Power on Magnetic Field and Frequency in Elongated Platelet \gamma -Fe _{2} O _{3} Particles Using Hysteresis-Loss Heating

    Publication Year: 2013 , Page(s): 4756 - 4760
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2608 KB) |  | HTML iconHTML  

    Elongated platelet γ-Fe2O3 particles with particle sizes of about 30 to 100 nm were prepared for magnetic thermoablation using hysteresis-loss heating of the ferromagnetic particles. The coercive force was based on the shape anisotropy of the elongated shape. The dependences of specific loss power (SLP) on the magnetic field strength and frequency were examined for particles in the range of 133 to 640 Oe and 117 to 429 kHz, respectively. The dependence of SLP on the magnetic field was similar to that of areas in minor hysteresis loops and showed that the heat generation in the particles was almost entirely based on hysteresis loss. To realize effective hysteresis-loss heating a magnetic field about four times stronger than the coercive force of particles was necessary. The SLP increased linearly with increasing frequency. Particles with a coercive force of 153 Oe showed an SLP of 1670 W/g under a magnetic field of 500 Oe and at a frequency of 429 kHz. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reducing Read Latency of Shingled Magnetic Recording With Severe Intertrack Interference Using Transparent Lossless Data Compression

    Publication Year: 2013 , Page(s): 4761 - 4767
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1322 KB) |  | HTML iconHTML  

    With the distinct advantage of retaining conventional head and media, the emerging shingled recording technology improves areal storage density through intentional track overlapping that nevertheless introduces severe intertrack interference (ITI). An economically tenable option for shingled drives is to utilize a single read head. As we continue to increase its areal storage density, there will be a higher probability that a read operation demands reading multiple adjacent tracks for explicit ITI compensation. This directly results in a significant read latency penalty when using a single read head. In this work, we propose a simple design strategy to reduce such ITI-induced read latency penalty. If a sector of user data can be compressed to a certain extent, it will leave more storage space for coding redundancy and, hence, opportunistically enable the use of a stronger-than-normal error correction code (ECC). The stronger ECC can accordingly reduce the probability of reading multiple adjacent tracks for explicit ITI compensation. Beyond a simple intrasector compression, the absence of the update-in-place feature in shingled recording makes it feasible to apply lossless compression across multiple consecutive sectors. This can further improve the compression efficiency and, hence, reduce the probability of reading multiple adjacent tracks. We carried out simulations that successfully demonstrate the effectiveness of the proposed design strategies on reducing the read latency penalty caused by severe ITI in shingled recording. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Low-Complexity Iterative Row-Column Soft Decision Feedback Algorithm for 2-D Inter-Symbol Interference Channel Detection With Gaussian Approximation

    Publication Year: 2013 , Page(s): 4768 - 4773
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (979 KB) |  | HTML iconHTML  

    In this paper, we study the complexity reduction problem of the iterative row-column soft decision feedback algorithm (IRCSDFA) for 2-D inter-symbol interference (ISI) detection. Specifically, Gaussian approximation (GA) is employed in both the component row and column detectors of the IRCSDFA in order to reduce its computational complexity. With the employment of GA, the state space dimension of the ISI trellis of either component detector can be reduced enormously (i.e., the number of branches in one ISI trellis section decreases). Bahl-Cocke-Jelinek-Raviv (BCJR) algorithm is then employed to perform detection over the GA-simplified ISI trellis. For brevity, we refer to the IRCSDFA with BCJR detection over the GA-simplified ISI trellis as “IRCSDFA-GA-BCJR”. Next, the iteration scheduling of component detectors and decoder in coded 2-D ISI channels with low density parity check (LDPC) coding and IRCSDFA-GA-BCJR detection is studied. Specifically, three iteration schemes: single detector (row or column) scheme, alternate detector scheme, and combined detector scheme, are considered, with the last scheme showing the best coded performance. Finally, the computational complexity of the proposed IRCSDFA-GA-BCJR is analyzed, and shown to have significant reduction with a cost of only about 0.3 and 0.35 dB in coded BER/FER performance loss compared to the conventional IRCSDFA without GA and the optimal symbol-based BCJR algorithm, respectively. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Novel Mat-Based System for Position-Varying Wireless Power Transfer to Biomedical Implants

    Publication Year: 2013 , Page(s): 4774 - 4779
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (850 KB) |  | HTML iconHTML  

    Wireless power transfer via magnetically resonant coupling is a new technology to deliver power over a relatively long distance. Here, we present a mat-based design to wirelessly power moving targets based on this technology. Our design is specifically applied to transcutaneously power medical implants within free-moving laboratory animals. Our system comprises a driver coil array, a hexagonally packed transmitter mat, a receiver coil, and a load coil, and generates a nearly flat magnetic distribution over a defined area to produce an approximately constant power output independent of the location of the receiver coil. This paper also describes a novel power receiver coil design of the same shape as the exterior of the implant, allowing for maximum magnetic coupling, eliminating the space restrictions due to the coil within the implant, and matching the resonant frequencies of the implant and the transmitter coil. Our new transmitter and receiver designs significantly reduce the size of a biomedical implant and may provide a lifetime power supply to implanted circuits without the need for an internal battery. Our designs are also useful in various other applications involving moving targets, such as part of a robot or a vehicle. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Tunable Left-Handed Characteristics of Ferrite Rectangular Waveguide Periodically Loaded With Complementary Split-Ring Resonators

    Publication Year: 2013 , Page(s): 4780 - 4784
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (935 KB) |  | HTML iconHTML  

    We propose, for the first time, a tunable left-handed (LH) waveguide consisting of an array of complementary split-ring resonators built on the broad wall of a rectangular waveguide filled with ferrite material. The left-handed behavior is caused by the negative permittivity of the complementary split-ring resonators together with the negative permeability of the transversely magnetized ferrite. The electromagnetic behavior of this structure is studied by means of an equivalent circuit model. From this model, the dispersion relation of the guide is derived and validated numerically by the finite element method. It is shown that this structure has a left-handed frequency band that can be tuned by changing the dc bias magnetic field applied to the ferrite. Compared to previous works, the fabrication requirements on this structure are not critical, which enhances its potential applicability. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Finite Element Analysis of Nondestructive Testing Eddy Current Problems With Moving Parts

    Publication Year: 2013 , Page(s): 4785 - 4794
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1931 KB) |  | HTML iconHTML  

    We present the logical expressions (LE) approach that allows fast computation of three-dimensional eddy current problems, including parts in motion. The approach applies time-dependent logical expressions to describe moving parts of the model on a fixed computational grid. The study is motivated by a novel nondestructive testing technique called Lorentz force eddy current testing (LET), which enables the detection of defects lying deep inside a conducting material. Depending on the definition of the frame of reference, we present two different implementations of the LE approach referred to as 1) moving magnet approach, and 2) moving defect approach. In order to demonstrate the advantages of the LE approach, we compare its results with the sliding mesh technique. The validation of the obtained results with experiments is also presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • MALTS: A Tool to Simulate Lorentz Transmission Electron Microscopy From Micromagnetic Simulations

    Publication Year: 2013 , Page(s): 4795 - 4800
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (906 KB) |  | HTML iconHTML  

    Here we describe the development of the MALTS software which is a generalized tool that simulates Lorentz Transmission Electron Microscopy (LTEM) contrast of magnetic nanostructures. Complex magnetic nanostructures typically have multiple stable domain structures. MALTS works in conjunction with the open access micromagnetic software Object Oriented Micromagnetic Framework or MuMax. Magnetically stable trial magnetization states of the object of interest are input into MALTS and simulated LTEM images are output. MALTS computes the magnetic and electric phases accrued by the transmitted electrons via the Aharonov-Bohm expressions. Transfer and envelope functions are used to simulate the progression of the electron wave through the microscope lenses. The final contrast image due to these effects is determined by Fourier Optics. Similar approaches have been used previously for simulations of specific cases of LTEM contrast. The novelty here is the integration with micromagnetic codes via a simple user interface enabling the computation of the contrast from any structure. The output from MALTS is in good agreement with both experimental data and published LTEM simulations. A widely-available generalized code for the analysis of Lorentz contrast is a much needed step towards the use of LTEM as a standardized laboratory technique. View full abstract»

    Open Access
  • Modeling and Analysis of Eddy-Current Damping Effect in Horizontal Motions for a High-Precision Magnetic Navigation Platform

    Publication Year: 2013 , Page(s): 4801 - 4810
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2057 KB) |  | HTML iconHTML  

    Recent advancements in micro/nano-domain technologies have led to a renewed interest in ultra-high resolution magnetic navigation platforms. A magnetic navigation platform (MNP) has been developed at the MagLev Microrobotics Lab of the University of Waterloo, Waterloo, ON, Canada. This platform consists of two separate basic components: a magnetic drive unit and a microrobot. The magnetic drive unit produces and regulates the magnetic field for noncontact propelling of the microrobot in an enclosed environment. The MNP is equipped with an eddy-current damper to enhance its inherent damping factor in the microrobot's horizontal motions. This paper deals with the modeling and analysis of an eddy-current damper that is formed by a conductive plate placed below the levitated microrobot to overcome inherent dynamical vibrations and improve motion precision. The modeling of eddy-current distribution in the conductive plate is investigated by solving the diffusion equation for vector magnetic potential. An analytical expression for the horizontal damping force is presented and experimentally validated. It is demonstrated that eddy-current damping is a key technique to increase the damping coefficient in a noncontact way and improve levitation performance. This damping can be widely used in applications of magnetic actuation systems in micromanipulation and microfabrication. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Improved Artificial Bee Colony Algorithm for Optimal Design of Electromagnetic Devices

    Publication Year: 2013 , Page(s): 4811 - 4816
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1009 KB) |  | HTML iconHTML  

    Optimal design problems of electromagnetic devices are generally multimodal, nondifferentiable, and constrained. This makes metaheuristic algorithm a good choice for solving such problems. In this paper, a newly developed metaheuristic algorithm is presented to address the aforementioned issues. The proposed algorithm is based on the paradigm of artificial bee colony (ABC). A drawback of the original ABC algorithm is because its solution variation is only 1-D, as this decreases its convergence speed. In this paper, a one-position inheritance scheme is proposed to alleviate this drawback. An opposite directional (OD) search is also proposed to accelerate the convergence of the ABC algorithm. The novel algorithm is applied to both TEAM Workshop problem 22 and a loudspeaker design problem. Both discrete and continuous cases of problem 22 are tested. The effectiveness and efficiency of the proposed algorithm are demonstrated by comparing its performance with those of the original ABC, an improved ABC known as Gaussian ABC, and differential evolution algorithms. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analytical and Semi-Analytical Solutions for the Force Between Circular Loops in Parallel Planes

    Publication Year: 2013 , Page(s): 4817 - 4823
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1972 KB) |  | HTML iconHTML  

    Closed-form solutions are presented for the force between noncoaxial coplanar circular current loops. A semi-analytical solution is given for the case where the loops lie in parallel planes. Numerical results are given which cross check these solutions against each other and against an independently developed method. The closed form solution for the force between a circular loop and a coaxial circular arc segment is also given. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Synthesis and Magnetic Behavior of Nickel Zinc Ferrite Nanoparticles Coated Onto Carbon Microcoils

    Publication Year: 2013 , Page(s): 4824 - 4826
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (425 KB) |  | HTML iconHTML  

    Magnetic nanoparticles consisted of nickel zinc ferrite (NZF) were chemically synthesized by co-precipitation and simultaneously coated onto carbon microcoils (CMC), and their structure and magnetic properties were investigated. The samples were prepared at various mass ratios of CMC : NZF ranging from 1 : 5 to 5 : 1. According to X-ray diffraction (XRD) measurements, all the samples synthesized in this study exhibit peaks associated with the spinel ferrite structure of NZF nanoparticles along with a fairly broad peak due to the amorphous structure of CMC. The sample synthesized at CMC: NZF = 1 : 1 gives the highest crystallinity and the largest magnetization at 300 K for NZF according to XRD and magnetization measurement using a superconducting quantum interference device magnetometer. Microstructural analysis of the CMC-NZF assemblies using scanning electron microscopy shows that the use of oleic acid and oleylamine improves the coverage of NZF on CMC and that the assembly made at CMC: NZF = 2 : 1 yields the highest coverage of NZF nanoparticles onto the CMC surface. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Magnetostrictive Performance in Py/TbFe Coupled Bilayers: Dependence on Hard Layer Thickness

    Publication Year: 2013 , Page(s): 4827 - 4830
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (560 KB) |  | HTML iconHTML  

    Magnetostrictive TbFe was chosen as hard layer, and the spin dynamics in the coupled bilayers Py(10 nm)/TbFe(t nm) (Py-permalloy; t=4, 7, 10, 30) were investigated by taking advantage of the engineering magnetostrictive strain under the constraints of the measurement. The dependence of the engineering magnetostrictive strain on TbFe layer thickness reflects a competitive process between the interfacial exchange interaction and the TbFe anisotropy. For the dominant interfacial exchange interaction in the coupled bilayers with 4 and 7 nm TbFe layer, coherent magnetization rotation of Py and TbFe layers is very similar to the behavior described by the Stoner-Wolfarth model. Magnetic hysteresis in the coupled bilayers with 10 nm TbFe layer and the decrease in the maximum engineering magnetostrictive strain in the coupled bilayers with 30 nm TbFe layer were observed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Materials Selection Exercise for Electromagnetic Launcher Rails

    Publication Year: 2013 , Page(s): 4831 - 4838
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1585 KB) |  | HTML iconHTML  

    Electromagnetic launchers (EML) are currently limited due to rail durability. The rail operating environment consists of large electrical currents, high local temperatures, large electromagnetic loads, and high sliding velocities. The desire to maximize magnetic energy for performance and durability for economic viability are the main objectives in selecting a rail material. A systematic process, often referred to as the Ashby method is used. The three steps include translating the design requirements into objectives and constraints, screening out materials that do not meet basic performance criteria, and ranking material candidates to maximize the objectives. Gouges, grooves, and fracture were identified as the three most life limiting forms of rail damage responsible for durability. Material property tradeoff plots show that magnetic energy and durability are conflicting objectives. A hybrid rail material in the form of a monolayer structure with an electrically conductive substrate and a damage resistant surface layer is the ideal configuration for maximizing the objectives. The results suggest that a conductive substrate, such as copper, is best for maintaining performance by means of magnetic energy and a damage resistant surface material consisting of tungsten, chromium, nickel, or tantalum has the best potential for increasing rail durability. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Metglas/PZT-Magnetoelectric 2-D Geomagnetic Device for Computing Precise Angular Position

    Publication Year: 2013 , Page(s): 4839 - 4842
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (945 KB) |  | HTML iconHTML  

    A magnetoelectric 2-D geomagnetic device for the precisely angular position computation is provided. The magnetic sensor module consists of two Metglas/PZT magnetoelectric 1-D sensors in an orthogonal arrangement. The sensor signals are excited and detected by a self-made digital lock-in amplifier. For mapping output sensor signals, normalization was performed on the operational module. Both spatial (azimuth and pitch) angles are then easily computed while rotating and/or swinging the sensor module. This simple and low-cost geomagnetic device is integrated with mobile transceivers for automatic determination and control of the latter antenna direction with respect to the position of the geostationary satellite in communication. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Planar Microcoil Optimization of MEMS Electrodynamic Microspeakers

    Publication Year: 2013 , Page(s): 4843 - 4850
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1012 KB) |  | HTML iconHTML  

    A method for optimizing the planar microcoil of MEMS electrodynamic microspeakers with the aim of maximizing the electroacoustic efficiency is presented. The proposed approach is based on a mixed-model using both analytical models and finite element method (FEM). FEM simulation was used for computing the spatial distribution of the magnetic field created by the permanent magnets, making thus possible to analyze any geometry of permanent magnets. Different configurations of magnets were considered, and for each the planar copper microcoil was optimized while taking into account the technological constraints due to the microfabrication process, the associated electronics and the targeted acoustic power emission. The results showed that the proposed method predicts the force factor in very good agreement with experimental measurements carried out on the micromachined device. Moreover, according to the electro-mechano-acoustic model, these results showed that the optimized microcoil associated to the best magnet configuration increases the electroacoustic efficiency by more than 200% compared to conventional microspeakers. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of a Mn–Zn Ferrite Bundle EMI Suppressor Using Different Suppressing Principles and Configurations

    Publication Year: 2013 , Page(s): 4851 - 4857
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1441 KB) |  | HTML iconHTML  

    A novel round cable electromagnetic interference (EMI) suppressor comprising a bundle of Mn-Zn ferrite tubes was realized using different principles of suppressing, such as direct suppressing, inverting/suppressing, transform/inverting suppressing, and transform/short circuited secondary suppressing. Different primary to secondary configurations were realized for each suppressing principle and characterized in the EMI frequency region. The results obtained for different bundle configurations were compared with known commercial round cable ferrite suppressors and the initial bundle configuration made of a half turn wire through the central ferrite tube of the bundle. The results obtained for different principles and configurations were correlated in order to optimize the electromagnetic coupling between primary and secondary circuits. The values such as maximums of impedance Zm, frequency of maximum impedance Fm and suppressing range Δf around Fm calculated on 0.707 Zm were defined as the main parameters for each configuration. Certain correlations were noticed between impedance Zm and frequency Fm changes. Finally, the realized configurations were considered as devices suitable for EMI suppressing applications. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Experimental Studies and New Feature Extractions of MBN for Stress Measurement on Rail Tracks

    Publication Year: 2013 , Page(s): 4858 - 4864
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1194 KB) |  | HTML iconHTML  

    The paper reports the design and implementation of magnetic Barkhausen noise (MBN) systems as well as its application and experiments for stress measurement on the rail track. Features of MBN signals including root mean square, average amplitude and pulse counts are calculated and analyzed, and a new feature the ratio of peak value and width at half maximum is introduced. All of these features of MBN signal decreases with the increase of compressive stress, but the feature of the ratio of peak value and width at half maximum has the fastest rate of decreasing against compressing stress which means that it has better sensitivity in stress measurement. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Closed-Double-Magnetic Circuit for a Long-Stroke Horizontal Electromagnetic Vibration Exciter

    Publication Year: 2013 , Page(s): 4865 - 4872
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1748 KB) |  | HTML iconHTML  

    A novel closed-double-magnetic circuit (CDMC) was presented to achieve high and uniform magnetic flux density (MFD) in the long air gap (LAG) of a long-stroke horizontal electromagnetic vibration exciter. First, the normal single-magnetic circuit (SMC) and the proposed CDMC were modeled by lumped element circuit using equivalent circuit principle, analyzed theoretically by the Kirchhoff's law and the superposition theorem. The comparison between the two circuits shows that the CDMC can have more intensive and more uniform MFD in the LAG. To strengthen the uniformity of the MFD in the LAG, the improved CDMC with uneven air gap and its design method were proposed theoretically. Thereafter, the uneven air gap structure expressed as a three-line-segment form was presented and its optimization was also conducted based on a finite element model referring to a prototype of a one-meter-stroke horizontal electromagnetic vibration excite. Then, the magnetic flux leakage of the magnetic circuits and the influence of slits in the outer magnetic yoke for practical application was also analyzed with the finite element method (FEM). The simulation demonstrates that the CDMC with optimal air gap can further improve the uniformity of the MFD in the LAG. In addition, it is also indicated that the CDMC has less flux leakage than the SMC and the influence of slits can be negligible. Finally, the experiment on the prototype also verifies the effectiveness of proposed CDMC with optimal air gap. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analytical 2-D Calculations of Torque, Inductance, and Back-EMF for Brushless Slotless Machines With Surface Inset Magnets

    Publication Year: 2013 , Page(s): 4873 - 4884
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3802 KB) |  | HTML iconHTML  

    In this paper, the electromagnetic torque, reluctance torque, inductance, and back-EMF are analytically calculated for brushless slotless machines with surface inset magnets. The calculations are based on the 2-D analytical magnetic field distributions. Although the expressions can be used for any magnetization patterns, the effects of three different magnetization patterns, i.e., radial, parallel, and Halbach, on the developed torque, back-EMF and inductances are examined. Besides, the influences of three types of armature current waveforms (sinusoidal, ideal rectangular, and six-step rectangular) on the mentioned quantities are investigated. The effects of pole arc per pole pitch ratio on the performance of slotless brushless machines are also studied. To evaluate the proposed 2-D analytical expressions, the analytical results are compared with those obtained by finite element analyses. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Influence of the Stator Windings Configuration in the Currents and Zero-Sequence Voltage Harmonics in Permanent Magnet Synchronous Motors With Demagnetization Faults

    Publication Year: 2013 , Page(s): 4885 - 4893
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1507 KB) |  | HTML iconHTML  

    Demagnetization faults in permanent magnet synchronous motors may generate specific fault harmonic frequencies in the stator currents and the zero-sequence voltage component (ZSVC) spectra. Hence, by analyzing the stator currents or/and the ZSVC spectra it is possible to develop fault diagnosis schemes to detect such faults. In order to have a broad view of such effects, a representative set of stator windings configurations must be considered. By analyzing different stator windings configurations this paper shows that the amplitude of the harmonic frequencies of both the stator currents and the ZSVC spectrato be analyzed are significantly influenced by the stator windings configuration. It is also proved that depending on the winding configuration, new harmonic components may emerge in both spectra. The results presented in this paper may help to develop fault diagnosis schemes based on the acquisition and further analysis of the stator currents and the ZSVC harmonic components. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

IEEE Transactions on Magnetics publishes research in science and technology related to the basic physics and engineering of magnetism, magnetic materials, applied magnetics, magnetic devices, and magnetic data storage.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Pavel Kabos
National Institute of Standards and Technology