Download or read book Analytical and Experimental Analysis of Losses in Inverter fed Permanent Magnet High speed Machines with Surface mounted Magnets written by T. Lu and published by . This book was released on 2002 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Speed Operation of Permament Magnet Machines written by Ayman M. El-Refaie and published by . This book was released on 2005 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Limits Modeling and Design of High Speed Permanent Magnet Machines written by Aleksandar Borisavljevic and published by Springer Science & Business Media. This book was released on 2012-10-31 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a growing number of applications that require fast-rotating machines; motivation for this thesis comes from a project in which downsized spindles for micro-machining have been researched. The thesis focuses on analysis and design of high-speed PM machines and uses a practical design of a high-speed spindle drive as a test case. Phenomena, both mechanical and electromagnetic, that take precedence in high-speed permanent magnet machines are identified and systematized. The thesis identifies inherent speed limits of permanent magnet machines and correlates those limits with the basic parameters of the machines. The analytical expression of the limiting quantities does not only impose solid constraints on the machine design, but also creates the way for design optimization leading to the maximum mechanical and/or electromagnetic utilization of the machine. The models and electric-drive concepts developed in the thesis are evaluated in a practical setup.

Download or read book Third Harmonic Utilization in Permanent Magnet Machines written by Kai Wang and published by Springer. This book was released on 2018-08-29 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book investigates the utilization of harmonics in the permanent magnet (PM) or rotor shape to improve the torque density of PM brushless AC machines including three-phase inner rotor and outer rotor machines, five-phase machines, dual three-phase machines, linear machines, by means of analytical, finite element analyses, and as well as experimental validation. The torque density can be improved while the torque ripple remains low in PM shaping utilizing the 3rd harmonic. In this book, the analytical expression of output torque is derived for PM machines with rotor shape using the 3rd harmonic, and then the optimal 3rd harmonic for maximizing torque is analytically obtained. The book compares the PM shape in surface-mounted PM (SPM) machines and the rotor lamination shape in interior PM (IPM) machines utilizing the 3rd harmonic, and it becomes clear that their shaping methods and amount of torque improvement are different. In a five-phase PM machine, the 3rd harmonic can be utilized in both the current waveform and PM shapes to further improve the output torque. For the dual three-phase SPM machines without deteriorating the torque more than 30% when the optimal 3rd harmonic into both the current and PM shape are injected. The harmonics in airgap flux density have significant influence on the cogging torque, stator iron flux distribution, and radial force between the rotor and stator. These effects has been investigated as well in this book.

Download or read book Advanced Theory of Fractional Slot Concentrated Wound Permanent Magnet Synchronous Machines written by Mohammad Farshadnia and published by Springer. This book was released on 2018-03-27 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the analytical modeling of fractional-slot concentrated-wound (FSCW) interior permanent magnet (IPM) machines and establishes a basis for their magnetic and electrical analysis. Aiming at the precise modeling of FSCW IPM machines’ magnetic and electrical characteristics, it presents a comprehensive mathematical treatment of the stator magneto-motive force (MMF), the IPM rotor non-homogeneous magnetic saturation, and its airgap flux density. The FSCW stator spatial MMF harmonics are analytically formulated, providing a basis on which a novel heuristic algorithm is then proposed for the design of optimal winding layouts for multiphase FSCW stators with different slot/pole combinations. In turn, the proposed mathematical models for the FSCW stator and the IPM rotor are combined to derive detailed mathematical expressions of its operational inductances, electromagnetic torque, torque ripple and their respective subcomponents, as a function of the machine geometry and design parameters. Lastly, the proposed theories and analytical models are validated using finite element analysis and experimental tests on a prototype FSCW IPM machine.

Download or read book Permanent Magnet Synchronous Machines with Fractional Slot and Concentrated Winding Configurations written by Wei-Zhong Fei and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The permanent magnet synchronous machines with fractional slot and concentrated winding configuration have been steadily gaining traction in various applications in recent times. This is mainly driven by several advantages offered by this configuration such as high-torque density, outstanding efficiency, and easy and low-cost fabrication. The main focus of this thesis is dedicated to the investigation of three main topologies of fractional-slot and concentratedwinding permanent magnet synchronous machines specifically suited for particular applications. Additionally, the cogging torque and torque ripple reduction technique based on a novel axial pole pairing scheme in two different radial-flux permanent magnet synchronous machines with fractional-slot and concentratedwinding configuration are investigated. First, an axial flux permanent magnet segmented-armature-torus machine with laminated stator is proposed for in-wheel direct drive application. Both simplified analytical method and three-dimensional finite element analysis model accounting for anisotropic property of lamination are developed to analyze the machine performance. The predicted and experimental results are in good agreement and indicate that the proposed machine could deliver exciting and excellent performance. The impact of magnet segmentation on magnet eddy current losses in the prototype is carried out by the proposed three-dimensional finite element analysis model. The results show that the eddy current losses in the magnet could be effectively reduced by either circumferentially or radially segmenting the magnets. Furthermore, a magnet shaping scheme is employed and investigated to reduce the cogging torque and torque ripple of the prototype. This is validated using the three-dimensional finite element analysis model as well. Second, a coreless axial flux permanent magnet machine with circular magnets and coils is proposed as a generator for man-portable power platform. Approximate analytical and three-dimensional finite element analysis models are developed to analyze and optimize the electromagnetic performance of the machine. Comprehensive mechanical stress analysis has been carried out by threedimensional structural finite element analysis, which would ensure the rotor integrity at expected high rotational speed. The results from both three-dimensional finite element analysis and experiments have validated that the proposed prototype is a compact and efficient high speed generator with very simple and robust structure. Additionally, this structure offers simplified assembly and manufacturing processes utilizing off-the-shelf magnets. Third, a novel radial flux outer rotor permanent magnet flux switching machine is proposed for urban electric vehicle propulsion. Initial design based on the analytical sizing equations would lead to severe saturation and excessive magnet volumes in the machine and subsequently poor efficiency. An improved design is accomplished by optimizing the geometric parameters, which can significantly improve the machine efficiency and effectively reduce the overall magnet volumes. Magnet segmentations can be employed to further improve the machine performance. Finally, a novel axial pole pairing technique is proposed to reduce the cogging torque and torque ripple in radial flux fractional-slot and concentrated-winding permanent magnet synchronous machines. The implementation of the technique in outer rotor surface mounted permanent magnet synchronous machine shows that the cogging torque and torque ripple can be reduced very effectively with different magnet pairs. However, careful pair selection is of particular importance for compromise between cogging torque and torque ripple minimizations during the machine design stage. This technique is also employed to minimize the cogging torque in a permanent magnet flux switching integrated-stator-generator and it is compared with rotor step skewed technique. The estimated and experimental results show that the axial pole pairing technique can not mitigate the torque ripple of the machine as effectively as rotor step skewed approach although both the techniques could reduce the cogging torque to the same level.

Download or read book Eddy current Losses in the Sleeves of High speed Synchronous Permanent magnet Machines written by David M. Saban and published by . This book was released on 2006 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optimization of multiphase permanent magnet synchronous machines on system level with reduced losses written by Dhamodaran. Nidhesh and published by BoD – Books on Demand. This book was released on 2022-01-01 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: The requirements of an electrical machine (EM) in Electric- (EV) and Hybrid Electric Vehicles (HEV) are high power density, a stator and rotor field with low harmonic content and best acoustic behavior. Six-phase permanent magnet synchronous machines (PMSM) have significant benefits over conventional three-phase PMSMs, such as reduced current per inverter phase leg, less fundamental losses because of a better winding factor and increased fault tolerance. Despite their advantages, considering the same installation space, the torque per ampere increase of a six-phase PMSM is very marginal. Therefore, the main focus of this dissertation lies in increasing the power density of the multiphase electric drive, where optimizations and investigations are done on a system level. System level simulation models, which consist of the power electronics, different control strategies and the electrical machines are developed and studied. Considering the electrical and mechanical phase shift between the two three-phase winding sets, different winding concepts of the sixphase EM are developed, in an effort to gain a better understanding of their advantages and disadvantages. Detailed analyses are performed, in order to understand the sources and influences of the space harmonics and high frequency inverter-induced time harmonics on the losses and performance of the EM. In particular, this dissertation will examine the EM torque, iron losses, magnet losses and copper losses for both inverter switched currents and sinusoidal currents supply.

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 1904 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Operation of Permanent Magnet Machine for Integrated Starter generator Application in Series Hybrid Bus written by Sinisa Jurkovic and published by . This book was released on 2009 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On the Design of Rare earth free and Reduced Rare earth Permanent Magnet Machines for High performance Traction Applications written by and published by . This book was released on 2015 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation focuses on techniques to design electric machines that approach the torque density and other key performance metrics of modern rare-earth permanent magnet (PM) machines, while limiting or eliminating the use of rare-earth materials. A wide variety of candidate PM machine topologies have been evaluated to determine their suitability to meet this objective based on a number of design and performance characteristics. Of major interest is the ability of each topology to shield the magnets from demagnetizing flux that is imposed by the stator winding currents. One particular topology - a PM-sandwiched flux-switching permanent magnet (FSPM) machine - is examined in detail. Closer examination has shown that this PM-sandwiched FSPM machines offers several attractive features including increased demagnetization-withstand capability, a critically important feature for the application of non-rare-earth PM materials. Several of the desirable performance features of the PM-sandwiched FSPM machine have their origin in its boosted magnet content compared to many other PM machine topologies. This property increases the magnetic loading without violating the geometric constraints imposed by the conventional FSPM machine geometry. As a result, the torque-per-current performance metric of the PM-sandwiched FSPM machine exceeds that of traditional IPM machines as well as conventional FSPM machines. When carefully designed, the predicted performance of the PM-sandwiched FSPM machine delivers higher efficiency over much of the torque-speed operating region. A concept demonstrator PM-sandwiched FSPM machine has been constructed using ferrite magnets to validate the analytical results. Test results for the machine are presented and compared to the calculated performance characteristics using finite element (FE) and closed-form analysis. Agreement between performance predictions based on FE analysis and experimental test results is quite good for the machine's back-emf and torque-per-current characteristics. However, discrepancies were encountered during experimental testing of the machine's efficiency. Closer examination showed that, when the extraneous/parasitic loss components are appropriately considered, the agreement between the predicted losses of the PM-sandwiched FSPM machine and the experimental test results is much improved. In addition to building confidence in the predicted performance advantages of the PM-sandwiched PM machine, the experimental testing also exposed the potential efficiency penalties imposed by various parasitic loss mechanisms.

Download or read book Advanced Permanent Magnet Machines and Drives written by Quntao An and published by Mdpi AG. This book was released on 2023-01-30 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reprint is comprised of eleven articles that are screened by our hard-working peer reviewers. It mainly focuses on the recent advances in electric motors and drives, to adapt to the ongoing trends of electrification in both transportation and industry. New structural motors, such as the axial flux machine and the multi-phase machine, are introduced because of their enhanced reliability for use in next-generation electrified transportation. Special attention is also given to the micro PM motor, which has a broad use in many areas. In addition, advanced control techniques, such as position sensorless control and fault-tolerant control, are also incorporated to fulfill the demand for safe crucial applications, and the modeling of the bearing voltage and a line-start permanent magnet motor can be of particular interest to the industrial sectors. Through this reprint, we hope to provide a new perspective for the readers to manage their encountered problems, as well as stimulate innovative ideas for the electrified transportation of the next generation.

Download or read book Modeling of Permanent Magnet Machines Using Field Reconstruction Method written by Lei Gu and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Permanent magnet synchronous machine (PMSM) is becoming more prevalent in industry applications due to its high power and torque density. The magnetic field distribution in the airgap of the motor is critical in predicting the performance, as well as implementing optimal design and control. Conventional methods to calculate the magnetic field include analytical lumped model, equivalent magnetic circuit (EMC) method, and finite element analysis (FEA) method. However, they have their limitation in terms of accuracy and computation time. Field reconstruction method was recently proposed for modeling of a surface mounted permanent magnet synchronous motor (SPMSM). It provides a fast method to reconstruct the magnetic field distribution with both high computation efficiency and good accuracy. However, due to the partial saturation effect in interior permanent magnet synchronous machine (IPMSM), conventional FRM method cannot be directly applied for modeling of IPMSM. An extended FRM (EFRM) is proposed to overcome the issue of partial saturation and slotting effect in IPMSM. Conformal mapping (CM) was recently proposed to calculate the magnetic field analytically. In general, CM is to map the complicated air gap structure into a simplified structure such as a rectangle or an annulus, in which the analytical solution of the magnetic field is readily available. The analytical solution of the magnetic field in simplified geometry is then transferred back to obtain the magnetic field distribution in original air gap geometry. Also, the effect of stator slots can be modeled with an equivalent permeability. As such original stator slots are transfomed into a slotless structure. This greatly simplifies the process of CM. What’s more, considering the equivalent permeability method would simplify the stator slot to a slotless structure which would greatly reduce the time to build the basis functions in EFRM. The combination of EFRM and CM would be an effective method to model IPMSM. In summary, CM shows a great advantage in achieving high calculation efficiency in modeling of PMSM though the accuracy is limited by only the saturation effects. The application of EFRM is extended to calculate the core loss and to estimate the average torque in PMSM. FEA simulation and experiments are conducted to verify the effectiveness of the proposed methods.

Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2003 with total page 774 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theses on any subject submitted by the academic libraries in the UK and Ireland.

Download or read book Analytical Representation and Finite Element Analysis of Magnetically geared Permanent Magnet Machines written by Sajjad Mohammadi Yangijeh and published by . This book was released on 2019 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, magnetic gears have drawn significant interest as a promising alternative to their mechanical counterparts by introducing features such as generating high torque at low speed, reduced acoustic noise and vibrations, low maintenance, inherent overload protection, improved reliability, physical isolation between shafts, and contactless power transfer. Conventional electrical machines can be combined with magnetic gears to form a compact device called a magnetically-geared machine. They have found their way into mechatronics, wind turbines, wave energy generation and electric vehicles. Such devices can be studied by numerical techniques or analytical frameworks. The former such as finite element methods (FEM), although powerful, is expensive and time-consuming, while the latter approach like flux-tube based models provide a flexible yet reasonable solution for preliminary designs and optimizations. In this thesis, there has been a comprehensive study on flux-tube based modeling and finite element analysis of the machine. The stator is represented using flux-tube based carterâĂŹs coefficient and a surface current density. The permanent magnets are modeled by different approaches including magnetization density, Coulombian fictitious charges and Amperian currents. The air-gap permeances are also modeled by flux-tubes. Closed-form expressions for the magnetic fields has been extracted. The developed torques has been calculated by different techniques including Maxwell stress tensor, Lorentz force and Kelvin force density. These options provide designers with a universal and flexible framework, enabling them to pick the best technique according to the configuration and application. The field modulation concepts and the gearing effects have been investigated using the developed analytical framework as well as 2D and 3D FEM, whose results agree. Both radial-flux and axial-flux configurations, the two main structures of rotating electrical machines, have been studied as well.

Download or read book Design of axial flux permanent magnet low speed machines and performance comparison between radial flux and axial flux machines written by Asko Parviainen and published by . This book was released on 2005 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book VF PMSM Magnetization State Manipulation Trajectories Operating Within Inverter Drive Limits to Achieve Load Cycle Energy Loss Reduction written by Brent Steven Gagas and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to utilize the power conversion and loss reduction capabilities of variable flux permanent magnet synchronous machines (VF-PMSMs), magnetization state (MS) should be manipulated over a wide speed range. Existing MS manipulation methods have a large transient voltage requirement, which limits their applicability to relatively low speeds. In this work, these existing methods are shown to have a severe dynamic voltage limitation. Existing methods are extended, and several new methods, which have a significantly higher speed capability, are proposed: a straight line stationary frame flux linkage trajectory (SLFsT), and a reverse rotating current vector trajectory (RRCVT). Existing and proposed trajectory methods are organized into families and analyzed regarding their required voltage, high speed capability, torque ripple, duration, and transient loss using simulations and experiments. Trajectories are evaluated experimentally on a prototype-scale variable flux, flux intensifying interior permanent magnet synchronous machine (VFI-IPMSM) and an EV-scale VF-PMSM. The effect of torque ripple from various trajectories on an EV mechanical drivetrain is estimated. FEA and experiments are used to evaluate the transient energy loss per MS change. Investigation is done on the effects of magnet temperature, which are shown to effect the controllability of MS. Mitigation of these effects is achieved with a proposed closed loop implementation of the SLFsT (CL-SLFsT) method. Ultimately, driving cycle energy loss reduction capability of the MS manipulation methods are evaluated, and the CL-SLFsT method is shown to significantly reduce the energy loss.