Scheduled System Maintenance on May 29th, 2015:
IEEE Xplore will be upgraded between 11:00 AM and 10:00 PM EDT. During this time there may be intermittent impact on performance. For technical support, please contact us at onlinesupport@ieee.org. We apologize for any inconvenience.
By Topic

Magnetics, IEEE Transactions on

Issue 5  Part 2 • Date May 2012

 This issue contains several parts.Go to:  Part 1 

Filter Results

Displaying Results 1 - 22 of 22
  • [Front cover]

    Publication Year: 2012 , Page(s): C1
    Save to Project icon | Request Permissions | PDF file iconPDF (232 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Magnetics publication information

    Publication Year: 2012 , Page(s): C2
    Save to Project icon | Request Permissions | PDF file iconPDF (39 KB)  
    Freely Available from IEEE
  • Table of contents

    Publication Year: 2012 , Page(s): 1837 - 1838
    Save to Project icon | Request Permissions | PDF file iconPDF (62 KB)  
    Freely Available from IEEE
  • Effect of Grain Size on Structural and Magnetic Properties of CuFe _{2} O _{4} Nanograins Synthesized by Chemical Co-Precipitation

    Publication Year: 2012 , Page(s): 1839 - 1843
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (397 KB) |  | HTML iconHTML  

    CuFe2O4 nanograins have been prepared by the chemical co-precipitation technique and calcined in the temperature range of 200-1200°C for 3 h. A wide range of grain sizes has been observed in this sintering temperature range, which has been determined to be 4 to 56 nm. Formation of ferrite has also been confirmed by FTIR measurement through the presence of wide band near 600 and 430 cm-1 for the samples in the as-dried condition. Systematic variation of wave number has been observed with the variation of the calcination temperature. B-H loops exhibit transition from superparamagnetic to ferrimagnetic state above the calcination temperature of 900°C. Coercivity of the samples at lower calcination temperature of 900°C reduces significantly and tends towards zero coercivity, which is suggestive of superparamagnetic transition for the samples sintered below this temperature. Frequency spectrum of the real and imaginary part of complex initial permeability have been measured for the samples calcined at different temperature, which shows wide range of frequency stability. Curie temperature, Tc has been measured from temperature dependence initial permeability at a fixed frequency of 100 kHz. Although there is small variation of Tc with sintering temperature, the reduction of permeability with temperature drastically reduce for lower sintering temperature, which is in conformity with the change of B-H loops with the variation of sintering temperatures. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Influence of Remanence on Magnetostrictive Vibration and Hysteresis in Mn-Zn Ferrite Cores

    Publication Year: 2012 , Page(s): 1844 - 1850
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (498 KB) |  | HTML iconHTML  

    Previously, experimental results have been presented showing that Mn-Zn ferrite core losses rise significantly with dc bias levels due to an increase in magnetostrictive vibration. In addition, it has been shown that the presence of a high level of remanent flux density, Br, left within a core after the removal of a dc bias can significantly increase core losses and, therefore, influence the hysteresis loop shape. In this paper it is shown that this loss mechanism is rate-independent in nature; furthermore, it is proposed to originate from regions of irregular stress that are dependent on the magnetostrictive vibration of a core. Accordingly, it is also proposed that certain parameters of the Jiles-Atherton (J-A) model must be modified, in order to allow influence of Br on hysteresis loops to be shown. These modifications are consistent with the real physical effects experienced by a ferrite core in the presence of a high level of Br. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Micromagnetic Computer Simulated Scaling Effect of S-Shaped Permalloy Nano-Element on Operating Fields for and or or Logic

    Publication Year: 2012 , Page(s): 1851 - 1855
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (707 KB) |  | HTML iconHTML  

    The scaling effect of permalloy s-shaped element, a rectangular element with appendages, on operating fields, Hx and Hy, was investigated by micromagnetic computer simulations for and or or logic. The optimized combination of operating fields (Hx, Hy) was found to be (27.7±9.9, -16.7±8.8), (37.9±12.4, -25.9±6.0), and (42.2±8.8, -23.9±4.0) in kA/m for the 100, 50, and 30 nm long s-shaped elements, respectively. As the s-shaped element is scaled down, the allowable deviation from the optimized operating fields becomes smaller and optimized operating fields shift to higher field. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Novel Transverse-Flux Moving-Magnet Linear Oscillatory Actuator

    Publication Year: 2012 , Page(s): 1856 - 1862
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1044 KB) |  | HTML iconHTML  

    A novel transverse-flux moving-magnet linear oscillatory actuator (TMLOA) for a compressor is proposed and analyzed, which features a unique configuration composed of usual laminated stators and moving-magnet mover. It not only offers low manufacturing cost and great dynamic characteristics, but also provides high thrust force density for its transverse flux path. The magnetic field and thrust force are analyzed by three-dimensional finite-element model. The proposed model is also used for studying effects of the axial dimensions variation on the thrust force and stroke, and then the selection of axial parameters is obtained with reference to the amplitude and smoothness of thrust force. Finally, the measurements of a prototype validate the predicted results. It shows the proposed TMLOA is very suitable for linear reciprocating motion drive applications such as compressors and pumps. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Analytical Model to Study the Transfer of Magnetic Pattern From Videotape to Garnet Film

    Publication Year: 2012 , Page(s): 1863 - 1868
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (953 KB) |  | HTML iconHTML  

    The magneto-optical readout system based on a signal transfer from videotape to magnetic garnet film has been proposed. To find the garnet film suitable for this system, we developed an analytical pattern of transfer readout. The garnet film considered has a magnetization almost in-plane but slightly inclined with respect to the film plane. On the basis of this model, when a videotape on which the bit length of 0.4 μm was recorded and brought close to the garnet film, the tilt angle of magnetization was estimated to be about 5 degrees for the garnet film with thickness of 0.6 μm, magnetization of 3 × 10-2 Wb/m2, and saturation field of 39 kA/m. The transfer of bit patterns from videotape to garnet film was demonstrated by using a polarizing microscope. The dependence of signal level on bit length obtained by the readout experiment with laser beam in which videotape was moved agreed well with that predicted by calculation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Actuation of Novel Blood Pump by Direct Application of Rotating Magnetic Field

    Publication Year: 2012 , Page(s): 1869 - 1874
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (703 KB) |  | HTML iconHTML  

    This paper presents a magnetic centrifugal pump, driven by an external rotating magnetic field, for use in artificial heart-assist blood pumps. The magnet rotor in the pump is synchronized to a rotating magnetic field, which then causes the fabricated impeller to produce a centrifugal force in the pump. Because the pump is driven by the direct application of an external rotating magnetic field, the proposed pump does not require a shaft or mechanical bearings. Thus, the proposed mechanism and external driving source give the pump the advantages of compact size; wireless, battery-free operation; heat-free operation; and minimal risk of bacterial infections. The pump weight, length, and diameter are 34 g, 35 mm, and 20 mm, respectively. The compact size and performance make the device suitable for use in pediatric cardiac assistance pumps. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Algorithm for Calculation of the Self and Mutual Inductance of Thin-Walled Air Coils of General Shape With Parallel Axes

    Publication Year: 2012 , Page(s): 1875 - 1889
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (804 KB) |  | HTML iconHTML  

    The general method of calculation described in this paper is applicable to the calculation of the self and mutual inductance of thin-walled solenoids of general shape with parallel axes in both coaxial and non-coaxial relative positions. The method is based on the solution of integral equation, the validity of which is defined in the text and additionally the physical interpretation of each section of the equation is documented. The manner of utilization of the method is demonstrated for the cases known in systems with a circular solenoid and subsequently applied to the case of two solenoids of rectangular shape in a general relative position. In these cases, a similarly detailed algorithm is compiled and the measurements are then compared with the calculation results. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Modeling, Analyzing, and Parameter Design of the Magnetic Field of a Segmented Halbach Cylinder

    Publication Year: 2012 , Page(s): 1890 - 1898
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1063 KB) |  | HTML iconHTML  

    The Halbach magnet array has become more and more attractive in many electromagnetic engineering domains such as electrical motors for its potential features such as self-shielding and providing sinusoidal field distribution. This paper develops analytical models formulated in polar coordinates for predicting the field distribution of a segmented Halbach magnet cylinder with or without back iron. Based on the analytical models, the relationships between the air-gap flux density and four design parameters including pole-pair number, segment number per pole, permanent-magnet radial dimension, and air-gap length are analyzed. Further, the Taguchi method is employed to identify the settings of design parameters and determine the parameters which have a significant effect on the field distribution. The analytical models are verified by taking advantage of the finite-element method (FEM), which shows that all the results can be of considerable use in the design of permanent-magnet machines. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Techniques Mitigating Update-Induced Latency Overhead in Shingled Magnetic Recording

    Publication Year: 2012 , Page(s): 1899 - 1905
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (583 KB) |  | HTML iconHTML  

    Shingled writing has recently emerged as a promising candidate to sustain the historical growth of magnetic recording storage areal density. However, since the convenient update-in-place feature is no longer available in shingled recording, in order to update one sector, many sectors must be read and written back, leading to a significant update-induced latency overhead. This work develops two simple design techniques that can reduce such a latency overhead. Because the spatial locality of update-invoked read operations naturally enables the use of the 2-D read channel signal processing, the first technique aims to reduce update-invoked read latency by trading the SNR gain obtained by a 2-D read channel for higher disk rotation speed. Since update-induced latency overhead strongly depends on the location of the sectors being updated within each shingled region, the second technique aims to reduce the latency overhead by leveraging the data access locality in most real-time workloads in order to determine appropriate data placement. Through extensive simulations, we show that disk rotation speed boost assisted by a 2-D read channel can reduce the update latency by up to 33%, and data access characteristic sector placement can reduce the update latency by over one order of magnitude. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Subdomain Model for Predicting Magnetic Field in Slotted Surface Mounted Permanent-Magnet Machines With Rotor Eccentricity

    Publication Year: 2012 , Page(s): 1906 - 1917
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (825 KB) |  | HTML iconHTML  

    An analytical subdomain model for the prediction of open-circuit magnetic field in slotted surface-mounted permanent-magnet machines is developed in this paper, which considers the effect of rotor eccentricity. The magnetic field domain is divided into three types of simple and regular subdomains, viz. magnet, air gap, and stator slots. The analytical solution is derived by solving the field governing equations in each subdomain and applying the boundary conditions to the interfaces between these subdomains. The perturbation method is used to describe the effect of rotor eccentricity. The model accurately accounts for the effect of stator slots, the mutual influence between slots, and rotor eccentricity. The analytical model is validated by the corresponding finite-element results. The results show that the proposed subdomain model up to the first-order perturbation can accurately predict the open-circuit magnetic field in slotted surface-mounted permanent-magnet machines with rotor eccentricity. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Study on the Novel Coefficient Modeling for a Skewed Permanent Magnet and Overhang Structure for Optimal Design of Brushless DC Motor

    Publication Year: 2012 , Page(s): 1918 - 1923
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1452 KB) |  | HTML iconHTML  

    A novel coefficient modeling technique, using a coefficient estimation method, is introduced for a brushless DC (BLDC) motor with a skewed permanent magnet and overhang structure. To construct the novel coefficient, the 3-D FEM and a design of experiment (DOE) are utilized along with the moving least square method (MLSM). Also, to verify the accuracy of the novel coefficient modeling, the conventional coefficient modeling using LSM is constructed and compared. Then the novel coefficient is combined with an approximate model constructed by 2-D FEM for use with an optimal design algorithm. For the searching process to obtain an optimal point, the genetic algorithm (GA) is used. Three-dimensional FEM simulation is used to verify the accuracy of the novel coefficient for the optimal design. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Numerical Prediction of Electromagnetic Vibration and Noise of Permanent-Magnet Direct Current Commutator Motors With Rotor Eccentricities and Glue Effects

    Publication Year: 2012 , Page(s): 1924 - 1931
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1060 KB) |  | HTML iconHTML  

    Numerical models are developed to predict the electromagnetic vibration and noise of permanent-magnet direct current (PMDC) commutator motors when both rotor eccentricities and glue effects are involved. Finite-element method (FEM) and boundary-element method (BEM) are combined to analyze the electromagnetic, mechanical, and acoustical characteristics of the studied motor. By using the finite-element method, an electromagnetic field considered as the electromagnetic vibration and noise sources of the motor is calculated in the two-dimensional air-gap region. Based on the electromagnetic field, the radial and tangential magnetic forces exciting the structure of the motor are then obtained in the time and frequency domains. Consequently, the transient responses (accelerations) of the motor are simulated by applying the magnetic forces on the three-dimensional dynamic-structure finite-element model of the motor. Furthermore, the sound pressures radiated from the vibrating surface of the motor can be obtained by using the boundary-element method in the frequency domain. The numerical results agree well with those measured in the laboratory. The present research reveals that the static eccentricity distorts the distribution of the magnetic forces in the spatial domain. And the distorted magnetic forces mainly exaggerate the accelerations of the motor for the frequency range which is lower than the natural frequencies of the motor. In addition, the epoxide-resin glue between the permanent magnets and the stator can influence the vibrational and the acoustical characteristics of the motor. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Manufacturing Tolerances: Estimation and Prediction of Cogging Torque Influenced by Magnetization Faults

    Publication Year: 2012 , Page(s): 1932 - 1936
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (274 KB) |  | HTML iconHTML  

    Permanent-magnet excited synchronous motor servo drives are increasingly employed in industrial applications. During mass production, deviations from the ideal machine occur. Thereby, parasitic effects such as cogging torque and torque ripple are influenced in particular. For permanent-magnet excited machines, the magnet's quality is important. There are many possible failure configurations requiring the study of their influence on the machine's behavior. In this paper, an approach for the estimation of cogging torque considering magnetization faults is presented. This approach is applied to determine crucial configurations of permanent-magnet faults. The intent is to evaluate the influence of the faulty magnetic materials with its asymmetries on the later produced machine. In the process, analytical and numerical methods are combined whereby finally a small computational effort with accurate results is achieved. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimizing Efficiency Driver Comprising Phase-Locked Loop for the Single-Phase Brushless DC Fan Motor

    Publication Year: 2012 , Page(s): 1937 - 1942
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (851 KB) |  | HTML iconHTML  

    Because the single-phase brushless fan motor presents an inductive load, the winding current will lag the back-electromotive force (EMF) an unequal phase based on the different motor speed. In order to improve the efficiency and torque performance, adjusting the commutation angle to keep the optimizing commutation at different speed is necessary. In this paper, the new structure with low cost to achieve the optimizing commutation is accomplished by the concept of phase-locked loop (PLL) to synchronize the winding current and back EMF. The PLL IC CD4046 is adopted to develop a feedback circuit and performs the function of phase advance. The purpose is to force the winding current to be synchronized with the back-EMF. Finally, the related experimental results are used to confirm the feasibility and effectiveness of the proposed driving method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Design and Optimization of Arc Permanent Magnet Synchronous Motor Used on Large Telescope

    Publication Year: 2012 , Page(s): 1943 - 1947
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1097 KB) |  | HTML iconHTML  

    In this paper, we propose to analyze the cogging force of an arc permanent-magnet synchronous motor (Arc PMSM), which will be applied on the next generation large telescope. Finite element analysis (FEA) is carried out to analyze the cogging force of Arc PMSM by using planar cross sections. By adopting optimization methods, such as adjusting the length of stator and adopting fractional slot, the end cogging force decreased from 6.2 N·m to 2 N·m, and the slot cogging force decreased from 6.0 N·m to 0.67 N·m accordingly. A geometric optimization in regards to the relative positions of stators along the rotor is also contrived to reduce the end cogging force. Both simulation and experimental results show that the total toque ripple can be as little as 2%, which can satisfy the tracking accuracy of the telescope. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Method to Segregate Detent Force Components in Permanent-Magnet Flux-Switching Linear Machines

    Publication Year: 2012 , Page(s): 1948 - 1955
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1287 KB) |  | HTML iconHTML  

    Detent force in permanent-magnet (PM) linear machines is caused by both end effect and slot effect. Segregation of the detent force into its end-effect and slot-effect components is helpful to better analysis and design. For conventional PM linear machines, the end-effect component of detent force can be easily calculated in a related slotless linear machine model, where the slot effect is eliminated. However, the slotless model is not applicable to permanent-magnet flux-switching (PMFS) linear machines, where the magnets and core teeth are set together on either a same stator or a same mover. This is because the PMFS machines cannot work at all without the teeth or slots. Therefore, a new method for segregating the detent force in the PMFS linear machines is proposed in this paper. Since a linear machine can be considered as a part of a particular rotary machine with large radius, and furthermore, cogging torque in the PM rotary machine is caused by the slot effect only, thereby the slot-effect component of the detent force in the PMFS linear machine can be calculated from the cogging torque in a related rotary machine, while the residual of the detent force is the end-effect component. Both finite element analysis (FEA) and experimental results show that the proposed method works well for the PMFS linear machines. View full abstract»

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

    Publication Year: 2012 , Page(s): 1956
    Save to Project icon | Request Permissions | PDF file iconPDF (799 KB)  
    Freely Available from IEEE
  • IEEE Magnetics Society Information

    Publication Year: 2012 , Page(s): C3
    Save to Project icon | Request Permissions | PDF file iconPDF (30 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Magnetics institutional listings

    Publication Year: 2012 , Page(s): C4
    Save to Project icon | Request Permissions | PDF file iconPDF (136 KB)  
    Freely Available from IEEE

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