Global ETD Search
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 18 of 18 for “"Stator Windings"”.
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Transient analysis of six-phase synchronous machines
… coupling between the two sets of three-phase stator windings are included in the development of a d-q equivalent circuit. The six-phase machine is constructed from a three-phase machine by splitting the stator windings into two equal three-phase sets. The six-phase machine reactances and …
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Aspects of brushless doubly-fed induction machines.
… machine (BDFM)- an electric machine with two stator windings, a modified cage-rotor, and, when run synchronously, the electrical properties of a synchronous machine, i.e. precise speed and power-factor control. The first part of this dissertation is dedicated to the development of a two axis …
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A heat transfer finite element model of a high speed DC electric motor
… model incorporates the motor rotor assembly, stator windings, stator laminations, stator end windings, and the motor housing. Power dissipation is modeled as Joule heating in the motor winding elements and iron core losses in the stator laminations. The two-dimensional axisymmetric model is …
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Control and design of multi-use induction machines : traction, generation, and power conversion
… this is to design the machine with multiple stator windings where one winding acts as a primary for drive and power, and the others as secondaries for electrical power. The challenge is to control the mechanical outputs of torque and speed while independently regulating the electrical outputs …
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Development of a DFIG wind energy system for grid integration studies
… ensuring more efficient power conversion.The stator windings in a DFIG are directly connected to the grid while the rotor windings are connected to the grid via back to back converters. This allows for independent active and reactive power control through the rotor side convertor and lower …
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Calculation of Unbalanced Magnetic Pull in Cage Induction Machines
… of an induction motor is not concentric with the stator then an electromagnetic force is generated in a direction that will increase the eccentricity. This is called unbalanced magnetic pull (UMP). The first part of the work presented in this dissertation develops theoretical models which allow …
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Electronic rotor position sensing of switched reluctance motor
… a high frequency control level signal on the stator windings and measuring the response. The response is an indirect measure of the rotor position. The principle, design, and implementation of the sensor is described in this thesis. The proposed sensor is inexpensive compared to the available …
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Thermal Modelling of the Ventilation and Cooling inside Axial Flux Permanent Magnet Generators
… also demonstrates how the heat transfer in the stator windings is modelled in the generic thermal equivalent circuit. Two analytical models, which are the Simple Concentric Model (SCM) and Concentric-annulus Layer Model (CLM) were developed, for the evaluation of the thermal resistances of the …
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Brushless doubly-fed reluctance machine drive for turbo-electric distributed propulsion systems
… appropriate electrical excitations on the two stator windings for a given machine dimension while remaining within flux- and current-density limits. A single-objective optimization problem is formulated. The obtained results prove that while designs with equal electrical loadings on both …
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Ferrofluid flow and torque measurements in rotating magnetic fields
… centered inside a 2-pole or 4-pole motor stator winding, creating uniform or nonuniform rotating magnetic fields, respectively. The spindle rotates at a constant speed up to 100 rpm or is stationary in these measurements. Anomalous behaviors such as zero and negative magnetoviscosity are …
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Development of control techniques for direct AC‐AC matrix converter fed multiphase multi‐motor drive system
… (more than three‐phase) motors, where their stator windings are connected in either series or in parallel and the combination is supplied from a single multi‐phase power converter. This thesis explores the control techniques of multi‐phase direct AC‐AC converter for such specific series and …
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Current source based wind energy conversion system
… interface for a dual three-phase PMSG, with two stator windings, shifted by 30°. Both the generator and grid side dual PWM rectifier and inverters (CSR and CSI) of the WECS are controlled using selective harmonic elimination (SHE) for low semiconductor loss operation. The grid side CSI is …
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Condition Monitoring of VSD-fed Induction Motors
… of the Fourier transform to machine's stator current under steady state operating conditions [7]. The MCSA assumes that the motor is sufficiently loaded and operating under steady state conditions [19]. Despite its robustness, this fault diagnostic tool suffers nonnegligible drawbacks, …
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Development, manufacture, and qualification of stator components for a high-speed electric machine intended for aerospace applications
… and assembly of the PMSM's armature windings. The innovative winding design that is addressed is a key enabler to the machine's performance due to its ability to push electric loading to 40,000 A/m, while only using forced air cooling. Finally, the thesis concludes with a summary of …
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Variable air gap axial flux permanent magnet machine with mechanical field weakening
… controlled by a component of current in the stator windings. In surface-mount permanent magnet machines, however, electrical modification of the field strength is problematic, and the torque-speed curve quickly drops to zero above the rated speed. A method of weakening the field is still …
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Integrated on-board battery chargers for EVs based on multiphase machines and power electronics
… three-phase currents flow through machines’ stator windings, they are not capable of producing a torque; thus the machines do not have to be mechanically locked. The principal advantage is that either very few or no new elements are required in order to realise the charging process. Thus …
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On-line condition monitoring and detection of stator and rotor faults in induction motors.
… in this thesis investigates the detection of stator and rotor faults (i.e. shorted turn faults, eccentricity faults, and broken rotor bar faults) using three types of sensor signals (i.e. current, leakage flux, and vibration) under different loading conditions. The work is based on an …
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The impact of voltage unbalance and regulation on the life expectancy of LV induction machines
… in turn is used to predict the induction machine stator windings temperatures. Factors that are considered when analysing the impact of voltage unbalance and regulation on the life expectancy of machines include, the induction machine manufacturer, the size of the induction machine, the voltage …