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Showing 1 to 20 of 24 for “"magnetic saturation"”.
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Analysis and Modelling of Fractional-Slot Concentrated-Wound Interior Permanent Magnet Machines
… (IPM) machines and establishes a basis for their magnetic and electrical analysis. In the state of the art methods for analyzing such machines, the non-homogeneous magnetic saturation and the non-linear B-H curve of the rotor iron are not considered. Moreover, the effect of the FSCW stator on the …
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Double-frequency stator core vibration in large two-pole turbogenerators
… an on-line monitoring scheme.<br/><br/>Electromagnetic forces at the stator bofe are represented as tooth-tip forces formed from the integral of Maxwell stress over a slot pitch. Conversion to core-back vibration is by means of transfer coefficients derived from structural finite-element …
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Low frequency, in-situ vibrating sample magnetometer : electrical systems and control software design
… built to measure the in-situ properties of ferromagnetic catalysts. The instrument allows measurements to be taken during an experimental catalyst test run (in-situ). The vibration is performed by a motor crank arrangement frequency of 2 Hz. The software designed to control the instrument and the …
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Robust adaptive control of induction machines using the L1 control scheme
… of unknown machine electrical parameters. Magnetic saturation within an induction motor results in nonlinear, changing flux dynamics. Also, rotor resistance changes with temperature as the machine is heated due to normal use, resulting in more parametric uncertainty. The proposed control …
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Electromagnetic fields in relation to eddy current gauging
… aspects of the relationships between electromagnetic fields and a non-contact type of eddy current gauge, which utilises a cylindrical solenoid and coaxially positioned metallic bar, either ferrous or non-ferrous.A rigorous mathematical analysis of the eddy current gauging system is …
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Electromagnetic fields in relation to eddy current gauging
… aspects of the relationships between electromagnetic fields and a non-contact type of eddy current gauge, which utilises a cylindrical solenoid and coaxially positioned metallic bar, either ferrous or non-ferrous. A rigorous mathematical analysis of the eddy current gauging system is …
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Predictive control of electrical drives
… Reluctance Machine, taking into account the magnetic saturation effects too. They are based either on the traditional control strategy or on optimization criteria, such as the minimum steady state Joule losses condition and the fastest achievement of the reference torque value. Finally, a …
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Percolation phenomena in amorphous iron-nickel alloys
… to be good ferromagnets, with the expected ferromagnetic critical behavior. Nickel, however, serves as a paramagnetic diluent. The amorphous structure permits the production of alloys that span the entire concentration range from paramagnetic (p=O) to ferromagnetic (p=l). The phase diagram has …
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Modelling and control of a hybrid stepping motor
… results are possible only when the effects of magnetic saturation are avoided or when the machine is available for magnetic circuit tests to be carried out. A new method of predicting the static torque characteristic is explained in detail. The method described uses the machine geometry and the …
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Development of Novel Synthetic Methods for Size-Tunable Synthesis of Superparamagnetic Iron Oxide Nanoparticles
The properties of magnetic nanoparticles vary dramatically with size, so reproducibly controlling size is critical for practical applications. This is particularly true when moving into clinical settings, where regulatory approval requires demonstrated reproducibility in efficacy that can only be …
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Optimization of a magnetically saturable interior permanent-magnet synchronous machine drive
… IPM machine design is to model the magnetic saturation of the core in a manner that is accurate, flexible, and computationally fast for design optimization. A magnetically-saturable lumped parameter model (LPM) is developed for the optimized design of high-performance IPM synchronous …
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Magnetic vector potential based formulation and computation of nonlinear three dimensional magnetostatic fields and forces in electrical devices by finite elements
… applied to a practical example with considerable magnetic saturation. A method, for the calculation of saturated device winding inductance, is presented. This method is based on an energy perturbation technique and was successfully applied numerically and verified experimentally. Two methods for …
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Investigation of Spinel Ferrite Thin Films for Spintronics Applications
… their extremely high specific resistance, high saturation magnetization, high Curie temperature, and exceptional flexibility in tailoring magnetic properties. In this dissertation, we attempt to address a most critical issue impeding the successful integration of spinel ferrites in ferrite-based …
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THE ANALYSIS AND SIMULATION OF HYBRID STEPPING MOTORS USING THE PHASE PLANE APPROACH
… stepping motor. It incorporates an efficient magnetic structure to obtain a high output torque, while maintaining a position resolution of fifty parts per million.</p><p>All stepping motors are nonlinear devices and, therefore, control strategies have been difficult to develop and implement. A …
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CHARACTERIZATION AND MODELLING OF MAGNETO-AUXETICITY, THE MAGNETICALLY INDUCED AUXETIC BEHAVIOR, IN GALFENOL
… is expected to be observed under application of magnetic fields even under zero stress conditions. This work deals with systematically studying the magneto-elastic contributions in Galfenol samples between 12 and 33 atomic percent Ga as a non-synthetic (no artificial linkages, unlike foams) …
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Experimental investigation and constitutive modeling of the large deformation behavior of anisotropic steel sheets undergoing strain-induced phase transformation
… X-ray diffraction, neutron diffraction, magnetic saturation, and magnetic permeability measurements. The latter is then used to measure the evolution of the martensite content throughout mechanical experiments. The experimental program for different stress states includes experiments for …
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Modeling of magnetorheological elastomers
… and reversibly change with the application of a magnetic field. MREs are composed of a non-magnetic polymer matrix embedded with magnetic particles. These materials can also demonstrate magnetostriction, with large strains compared to the magnetostriction seen in crystalline solids. Ultrasoft …
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Fabrication and characterization of a magnetic bacterial nanocellulose for neurovascular reconstruction of cerebral aneurysms
… to months. We hypothesized that a material with magnetic properties can provide the force required to speed up re-endothelization across the aneurysm defect, since it can facilitate high cell density coverage at the damaged site in virtue of its ability to capture and retain magnetically …
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Enhancement of Inductive Power Transfer Technology: Iron-based Nanocrystalline Ribbon Cores
… material. This material offers a higher saturation flux density, a higher permeability, superior thermal performance, and mechanical robustness compared to the standard MnZn ferrites commonly used in IPT systems. A feasibility analysis of this material was carried using intricate finite …
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Analysis of a permanent magnet hybrid linear stepping motor
… should be improved to take into account the magnetic saturation and edge effects and the FEM enhanced classical approach should be attempted to take advantages of the high accuracy of the FEM without significant increase in the solution time.
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