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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 268 for “"Permanent magnet"”.
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Design optimization of permanent magnet actuators.
This study describes the design optimization of permanent actuators, of both rotary and linear topologies. Parameter scanning, constrained single and multi-criterion optimization techniques are developed, with due emphasis on the efficient determination of optimal designs. The modelling of devices …
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Radiation Damage in Permanent Magnet Lenses
… Alamos National Lab and elsewhere depend upon permanent magnet quadrupoles in their magnetic optics. Radiation exposure during radiography experiments is known to damage these lenses and degrade image quality. This effect is studied under controlled conditions, leading to the conclusion that …
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Magnetisation reversal in permanent magnet materials
… presents an investigation of the reversal of magnetisation in sintered anisotropic Nd-Fe-B, isotropic melt-spun Nd-Fe-B powder, and in Sm-(Co,Cu,Fe,Zr) 2:17 anisotropic powder. Magnetisation measurements have been performed using vibrating sample magnetometers, a permeameter, and an adapted …
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Torque estimation in permanent magnet synchronous machines
El uso de máquinas síncronas de imanes permanentes ha aumentado notablemente en aplicaciones industriales y de tracción eléctrica durante las últimas décadas, debido a su mejor comportamiento sobre otros tipos de motores eléctricos en aspectos clave como son la densidad de potencia, densidad de …
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New Sensorless Permanent Magnet Synchronous Motor Drive
In permanent magnet synchronous motor (PMSM) drives, magnetic-saliency-based techniques have been widely used to detect rotor position and speed, especially during the starting and low-speed operations. Among these techniques, pulsating high-frequency signal injection (PHFSI) stands out as a …
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A study of permanent-magnet torque motors
Thesis (M.S.) Massachusetts Institute of Technology. Dept. of Mechanical Engineering, 1953.
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Super High-speed Miniaturized Permanent Magnet Synchronous Motor
This dissertation is concerned with the design of permanent magnet synchronous motors (PMSM) to operate at super-high speed with high efficiency. The designed and fabricated PMSM was successfully tested to run upto 210,000 rpm The designed PMSM has 2000 W shaft output power at 200,000 rpm and at …
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Fault Tolerant Sensorless Permanent Magnet Synchronous Motor Drives
High cost and complexity of fault tolerant motor drives has relegated them to mission critical, no-compromise applications. Heeding to this target application, past research efforts have been mainly focused on developing highly redundant, multiphase fault-tolerant solutions able to assure a very …
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The Dynamic Stability of Permanent-Magnet Step Motors
Made available in DSpace on 2014-12-12T20:55:01Z (GMT). No. of bitstreams: 1 8004255.pdf: 8658158 bytes, checksum: c2bf13aec68772fdbbf6e865d3778542 (MD5) Previous issue date: 1979
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Rotordynamic assessment for a permanent magnet synchronous motor
… tip-speed, in particular, combined with high magnetic and electrical loading, are key enablers for obtaining high specific power in electric machines. The rotor described in this thesis pushes the tip speed to about 80% of the speed of sound. An outer rotor design with a carbon-fiber retaining …
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Design of a Vernier Permanent Magnet Wind Generator
… structure is as simple as a conventional permanent magnet (PM) machine, whilst eliminating the need for a mechanical gearbox. The research problem addressed by this dissertation relates to the assessment of the Vernier permanent magnet (VPM) machine topology for direct-drive wind …
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Phase-controlled rectification for permanent-magnet downhole alternators
… phase-controlled rectification to be used with permanent-magnet downhole alternators. The design faces unique challenges imposed by the downhole environment. The thesis discusses the design, simulation, and construction of the rectifier. A high-side semi-bridge phase-controlled model is …
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Failure monitoring in small permanent-magnet synchronous motors
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering, 1991.
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Development and Test of a Permanent Magnet Helicon Thruster
… thruster research. A helicon thruster using permanent magnets was also designed and tested. The helicon has several advantages, but the main disadvantage is the use of electromagnets to generate the required magnetic field, requiring a high power draw. The choice of using permanent magnets is …
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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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Development of high efficiency high speed permanent magnet generator
… the demand of electric energy. The High Speed Permanent Magnet (HSPM) generator is designed and developed and is expected to deliver 10 kW output power as well as to achieve a speed of 30000 RPM, however, to achieve a compact and efficient design with lower excitation losses, magnetizing …
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A novel magnetically levitated interior permanent magnet slice motor
A magnetically levitated motor, also known as a bearingless motor, combines the function of a magnetic bearing and motor to both levitate and rotate a rotor. This enables contact-free operation, which is advantageous in applications which require low friction, long operational lifetime, and high …
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A doubly-fed permanent magnet generator for wind turbines
… design is a doubly-fed, dual-rotor, axial-flux, permanent-magnet machine. Progress in the construction of a prototype is described. Analysis of the steady state and dynamic behavior of the machine is detailed, and a control algorithm developed therefrom.
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A fully-integrated multi-watt permanent-magnet turbine generator
… fabrication, and testing of a fully-integrated permanent-magnet turbine generator based on silicon MEMS technology envisioned to replace batteries. The air-driven device, supported on gas bearings, has been experimentally shown to deliver 19 mW to matched resistive loads of 0.33 [omega] while …
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