Energy Efficiency in Electric Devices, Machines and Drives

Energy Efficiency in Electric Devices, Machines and Drives

Author: Gorazd Štumberger

Publisher: MDPI

Published: 2020-06-18

Total Pages: 218

ISBN-13: 3039363565

DOWNLOAD EBOOK

This Special Issue deals with improvements in the energy efficiency of electric devices, machines, and drives, which are achieved through improvements in the design, modelling, control, and operation of the system. Properly sized and placed coils of a welding transformer can reduce the required iron core size and improve the efficiency of the welding system operation. New structures of the single-phase field excited flux switching machine improve its performance in terms of torque, while having higher back-EMF and unbalanced electromagnetic forces. A properly designed rotor notch reduces the torque ripple and cogging torque of interior permanent magnet motors for the drive platform of electric vehicles, resulting in lower vibrations and noise. In the field of modelling, the torque estimation of a Halbach array surface permanent magnet motor with a non-overlapping winding layout was improved by introducing an analytical two-dimensional subdomain model. A general method for determining the magnetically nonlinear two-axis dynamic models of rotary and linear synchronous reluctance machines and synchronous permanent magnet machines is introduced that considers the effects of slotting, mutual interaction between the slots and permanent magnets, saturation, cross saturation, and end effects. Advanced modern control solutions, such as neural network-based model reference adaptive control, fuzzy control, senseless control, torque/speed tracking control derived from the 3D non-holonomic integrator, including drift terms, maximum torque per ampere, and maximum efficiency characteristics, are applied to improve drive performance and overall system operation.


Switching Equipment

Switching Equipment

Author: Hiroki Ito

Publisher:

Published: 2019

Total Pages:

ISBN-13: 9783030007829

DOWNLOAD EBOOK

This CIGRE Green Book provides the entire know-how about switches in a high voltage system. The switching equipment includes circuit breakers, vacuum interrupters, disconnecting switches, and earthing switches used in AC & DC transmission and distribution systems. The Green book describes different switching equipments and their roles in the power systems. It explains the fundamental switching behaviors in power systems targeted for practitioners and students and joining electrical industries. The Green book also covers fundamental specific subjects including DC circuit breakers, controlled switching, fault current limiting devices and future technologies. Like all Green books, this book covers the cumulative understanding of numerous experts in the CIGRE study committee. It offers the approved and outstanding practical knowledge of CIGRE Study committee A3 and was collected by Dr. Hiroki Ito.


Mathematical Models for the Design of Electrical Machines

Mathematical Models for the Design of Electrical Machines

Author: Frédéric Dubas

Publisher: MDPI

Published: 2021-03-15

Total Pages: 252

ISBN-13: 3036503986

DOWNLOAD EBOOK

This book is a comprehensive set of articles reflecting the latest advances and developments in mathematical modeling and the design of electrical machines for different applications. The main models discussed are based on the: i) Maxwell–Fourier method (i.e., the formal resolution of Maxwell’s equations by using the separation of variables method and the Fourier’s series in 2-D or 3-D with a quasi-Cartesian or polar coordinate system); ii) electrical, thermal and magnetic equivalent circuit; iii) hybrid model. In these different papers, the numerical method and the experimental tests have been used as comparisons or validations.


Reluctance Electric Machines

Reluctance Electric Machines

Author: Ion Boldea

Publisher: CRC Press

Published: 2018-07-20

Total Pages: 416

ISBN-13: 0429857365

DOWNLOAD EBOOK

Electric energy is arguably a key agent for our material prosperity. With the notable exception of photovoltaic generators, electric generators are exclusively used to produce electric energy from mechanical energy. More than 60% of all electric energy is used in electric motors for useful mechanical work in various industries. This book presents the modeling, performance, design, and control of reluctance synchronous and flux-modulation machines developed for higher efficiency and lower cost. It covers one- and three-phase reluctance synchronous motors in line-start applications and various reluctance flux-modulation motors in pulse width modulation converter-fed variable speed drives. FEATURES Presents basic and up-to-date knowledge about the topologies, modeling, performance, design, and control of reluctance synchronous machines. Includes information on recently introduced reluctance flux-modulation electric machines (switched- flux, flux-reversal, Vernier, transverse flux, claw pole, magnetic-geared dual-rotor, brushless doubly fed, etc.). Features numerous examples and case studies throughout. Provides a comprehensive overview of all reluctance electric machines.


Design, Analysis and Application of Magnetless Doubly Salient Machines

Design, Analysis and Application of Magnetless Doubly Salient Machines

Author: Christopher H. T. Lee

Publisher: Springer

Published: 2018-01-22

Total Pages: 215

ISBN-13: 9811070776

DOWNLOAD EBOOK

This thesis investigates the key characteristics of magnetless doubly salient machines, evaluates their design philosophies, and proposes new topologies for various applications. It discusses the background of and previous research on magnetless machines, while also outlining upcoming trends and potential future developments. The thesis begins by presenting various torque-improving structures – namely the multi-tooth structure, the double-rotor (DR) structure, the axial-field (AF) structure, and the flux-reversal (FR) structure – for magnetless machines. It subsequently addresses the idea of merging the design philosophies of two different machines to form new dual-mode machines. Thanks to a reconfigured winding arrangement and controllable DC-field excitation, the proposed machines can further extend their operating range to meet the extreme demands of applications in electric vehicles and wind power generation. Lastly, the thesis employs the finite element method (FEM) to thoroughly analyze the proposed machines’ key performance parameters and develops experimental setups to verify the proposed concepts.


General Airgap Field Modulation Theory for Electrical Machines

General Airgap Field Modulation Theory for Electrical Machines

Author: Ming Cheng

Publisher: John Wiley & Sons

Published: 2022-12-06

Total Pages: 568

ISBN-13: 1119900360

DOWNLOAD EBOOK

General Airgap Field Modulation Theory for Electrical Machines Introducing a new theory for electrical machines Air-gap magnetic field modulation phenomena have been widely observed in electrical machines. This book serves as the first English-language overview of these phenomena, as well as developing systematically for the first time a general theory by which to understand and research them. This theory not only serves to unify analysis of disparate electrical machines, from conventional DC machines, induction machines, and synchronous machines to unconventional flux-switching permanent magnet machines, Vernier machines, doubly-fed brushless machines etc., but also paves the way towards the creation of new electrical machine topologies. General Airgap Field Modulation Theory for Electrical Machines includes both overviews of key concepts in electrical machine engineering and in-depth specialized analysis of the novel theory itself. It works through the applications of the developed theory before proceeding to both qualitative analysis of the theory’s operating principles and quantitative analysis of its parameters. Readers will also find: The collective experience of four award-winning authors with long records of international scholarship on this subject Three separate chapters covering the principal applications of the theory, with detailed examples Discussion of potential innovations made possible by this theory General Airgap Field Modulation Theory for Electrical Machines is an essential introduction to this theory for postgraduates, researchers, and electrical engineers.