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Basic structure of the AFPM machine with a coreless stator. 1: Stator winding. 2: Steel rotor. 3: PMs. 4: Frame. 5: Bearing. 6: Shaft.
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This paper describes a hybrid method for calculating the performance of a coreless stator axial flux permanent-magnet (AFPM) generator. The method uses a combination of finite-element analysis and theoretical analysis. The method is then incorporated into a multidimensional optimization procedure to optimally design a large power coreless stator AF...
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... schematic drawing of a typical coreless stator AFPM ma- chine is shown in Fig. 1. The machine consists of two outer rotor disks and one coreless stator in the middle. On the two op- posing rotor disks, there are surface-mounted permanent mag- nets (PMs). The coreless stator winding consists of a number of single-layer trapezoidal-shaped coils. These coils have the advantages of being easy to make and having ...
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... in the laboratory and were analyzed. The tests fo- cused on its generation mode. A reconfigurable water-cooled bank of resistors was configured into a balanced three-phase load and then connected across the AFPM machine terminals. An induction machine was used as prime mover. The water cooling system consists of a water tank, pipe system, and a Fig. ...
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... Fig. 11, the no-load phase voltage of the prototype ma- chine at rated speed calculated by a FE time-stepped model is compared with the measured results. The details of the time-step modeling of AFPM machine is given in [27]. The output power and phase current were measured at different rotating speeds. The same conditions were simulated using ...
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... is given in [27]. The output power and phase current were measured at different rotating speeds. The same conditions were simulated using the FE computer program. The load resistance value used in the computation under various load conditions was compensated with an esti- mated temperature factor. The results are presented and com- pared in Fig. 12. Agreement between measured and predicted output power and phase current is shown to be well within the limits of experimental ...
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The optimal design of a set of two permanent magnet generators that share the same cross section to reduce the manufacturing cost is presented using a gradient optimization algorithm. The optimization tool is used to define the optimal number of pole pairs of the set of machines and the optimal permanent magnets width respecting the geometrical and...
Citations
... Additionally, the unconventional design may require specialized production facilities compared to standard motor designs [88]. ...
This guidebook provides a comprehensive exploration of Hybrid and Electric Vehicles (HEVs and EVs), detailing their development, technologies, and environmental impacts. It begins with basic definitions and classifications, exploring HEV systems including Parallel, Series, Power-Split, Plug-in Hybrids (PHEVs), and Mild Hybrids (MHEVs), alongside EV types like Battery Electric (BEVs), Fuel Cell Electric (FCEVs), and Extended Range Electric Vehicles (EREVs). The book discusses significant technological advancements such as advanced battery technologies, powertrain systems, Vehicle-to-Grid (V2G) systems, and smart charging solutions that enhance vehicle efficiency and sustainability.
The text also examines the integration of smart technologies that improve HEVs and EVs' operational efficiency and interactive capabilities, and considers environmental impacts like emissions reduction and sustainable manufacturing practices. Additionally, it covers market dynamics, including consumer preferences and infrastructural developments essential for widespread vehicle adoption, alongside the effects of policies and regulations.
Looking forward, the guide speculates on the future integration of autonomous technologies, Mobility-as-a-Service (MaaS), and urban transportation innovations. Case studies provide insights into the practical applications and adaptability of HEVs and EVs. This resource aims to equip students, engineers, and policymakers with a thorough understanding of HEVs and EVs' roles in advancing sustainable global transportation.
... Le principe de fonctionnement, les différents modèles mathématiques et les principales caractéristiques de la machine synchrone à aimant permanent, ont été discutés en détail dans de nombreux travaux de recherche [120][121][122][123][124][125][126]. Dans cette partie, nous ne donnerons que quelques notions plus générales sur ce type des machines. ...
Au cours des dernières années, les besoins en
énergie sont de plus en plus croissants, et le recours à des
alternatifs d’énergies renouvelables ne cesse de grandir.
Le champ des éoliens contribuent d’une manière très
significative à combler les besoins en énergies. Pour aider
à développer le marché de l'éolienne, de nombreux
chercheurs et fabricants se sont concentrés ces dernières
années sur l'étude et l'amélioration des performances de
cette technologie, et ils travaillent notamment sur le choix
de la bonne structure d'éolienne tout en considérant le
coût approprié et un rendement de production élevé.
Dans cette thèse, nous avons concentré notre attention
sur l'amélioration du rendement de production des
systèmes éoliens de petite puissance par la mise en œuvre
d’un système de contrôle avancé. D’où, deux nouvelles
techniques MPPT (Maximum Power Point Traking) de
hautes performances, sans capteur de la vitesse du vent et
sans aucune connaissance préalable des paramétrés de la
turbine ou de la génératrice ont été proposées. De plus,
pour faciliter l’étude des éoliennes et la validation
expérimentale des techniques MPPT proposées sans le
besoin d’accéder à la turbine elle-même ou de connaître
leur ressource naturelle (le vent), ce travaille propose le
dimensionnement d’un nouvel émulateur à faible coût
pour les éoliennes de petite puissance.
L'efficacité et la faisabilité de la chaîne éolienne
étudiée avec les différents schémas de commande
proposés dans ce travail ont été évaluées à l’aide du
logiciel de simulation MATLAB/Simulink, ainsi
qu'expérimentalement par un banc d’essai à base d’un
émulateur éolienne et d’une carte dSPACE1104. De plus,
plusieurs scénarios ont été adoptés pour la validation, y
compris l’influence de la variation de la vitesse du vent,
l’influence du changement de la charge électrique et
même l’effet de l’inertie de la turbine éolienne est pris en
considération. Les résultats expérimentaux obtenus sont
très satisfaisants et sont très similaires à ceux obtenus par
simulation.
Mots-clés– Turbine éolienne, émulateur, contrôle avancé,
convertisseur Boost, GSAP, MCC, MPPT, MATLAB/
Simulink, dSPACE1104.
... As shown in ref. (23), the copper loss P copper_loss consists of two parts: the winding ohmic loss P ohmic_loss and the winding eddy-current loss P eddy_current_loss , which are given by refs. (24) and (25), respectively [21]. P copper loss ¼ P ohmic loss þ P eddy current loss ð23Þ P ohmic loss ¼ mR s I 2 ð24Þ ...
... where P h and P e are the hysteresis loss and the eddy-current loss, respectively; k h , n and k e are the core loss coefficients. In PMR, the frequency of the natural magnetic field is zero, while that of the modulated magnetic field is nonzero, as shown in ref. (21). Hence, only the modulated component leads to core loss, while the natural component has no contribution. ...
... Hence, from refs. (21), (22) and (26), it can be deduced that in CS-MGDRM, the core loss is proportional to the speed difference. ...
Magnetic‐geared double‐rotor machines are recognized as a promising power‐splitting component in hybrid electric aircrafts (HEAs). However, the high fuel efficiency speed of the turbine engine in HEAs is about 10,000 rpm, whereas conventional topologies suffer from low efficiency at high speed due to its specific operation principle—the magnetic field modulating principle. A coreless stator magnetic‐geared double‐rotor machine (CS‐MGDRM) is proposed to enhance high‐speed efficiency and thus comply with the operation condition of HEAs. First, the machine structure and hybrid propulsion system configuration are introduced, and power‐flow analysis of three basic operation modes is presented. Second, the operation principle of the machine is illustrated, and investigation of electromagnetic performances is carried out by finite element analysis. Third, an analytical model of the machine is developed, based on which the design optimization towards the maximum torque capacity is investigated. Furthermore, the loss distribution law and transmission efficiency are analysed and compared with conventional scheme, and the power factor characteristic is investigated as well. Finally, the overall performance of the proposed machine is evaluated.
... Axial Flux Permanent Magnet (AFPM) machines with ironless topology have recently found growing interest, as an attractive alternative to other PM machines due to their high efficiency, low inertia, compact construction, and high power/torque densities, and low cogging torque [1], [2]. Because of the inexistence of iron losses, the ironless AFPM machines are particularly suitable to be used in a wide range of low or high-speed direct-drive applications, such as wind turbines generators [3], [4], airplanes [5], and traction [6]. ...
... The operation of AFPMG depends on many aspects. Besides the generator's construction, one of the most significant factors is the magnet selection: volume, shape and the magnet type [9][10][11][12][13][14][15][16][17][18][19][20][21]. For this purpose, analytical models as well as field models (FEM) are used. ...
... For this purpose, analytical models as well as field models (FEM) are used. Analytical models are very useful and are often used by engineers dealing with exploitation as well as by constructors in the initial stages of works [9][10][11][12][13][14]. ...
... where: (12) w s -the whole turns number of the stator phase winding, k |ς| s -the winding factor for ς th harmonic [7,39,40]: ...
In this article, the field (FEM) and analytical analyses were used for the optimal selection of magnets material for the Axial Flux Permanent Magnet Generator (AFPMG), without building the prototype before. The tested generator is an axial flux machine which consists of a single stator and two rotor discs with Permanent Magnets (PM). Three-dimensional (3D) ANSYS Maxwell package was used for magnetostatic and transient field (FEM) simulations. Two types of PM were selected for the analysis: Ceramic (also known as “Ferrite”) magnets made from Strontium Ferrite powder and Neodymium Iron Boron magnets (NdFeB). The authors compared obtained electromotive forces (EMF) and generator powers for selected magnets materials, performed FFT analyses of voltages and currents and indicated the optimal solutions. In addition to the operational properties of the AFPMG, the magnet and manufacturing costs were compared.
... However, none of these methods can eliminate cogging torque. This article is based on the TRIZ book by the Soviet inventor Altshuller, (10)(11)(12) (English translation: "Inventor-style tasksolving theory", abbreviated to TRIZ). This is also known as the theory of inventive problem solving (TIPS), which can be understood as an inventive problem-solving theory. ...
... Compared with the conventional radial flux permanent magnet (PM) machine, the axial flux permanent magnet (AFPM) machine can be used in some special applications such as electric vehicles [1], wind turbine systems [2], and unmanned aerial vehicles [3] due to its short axial size, compact structure, disk-shaped profile, and high efficiency. The AFPM machine has a variety of classical structures; wherein, the configuration with double rotors and a single stator is preferred chiefly [4,5], and the stator core is not necessarily required to form a closed magnetic circuit in the design. By eliminating the iron core of the stator, the coreless AFPM machine has the following advantages [6][7][8]: (1) The quality and cost of the machine are reduced; (2) The loss of the stator core and the cogging torque of the machine are eliminated; (3) The inductance of windings is small, and the influence of the stator current on the air gap flux density is almost negligible; (4) The ability of overload is greatly improved; (5) The arrangement of coils is more flexible and not constrained by slots and teeth of the stator. ...
In this paper, a type of novel composite structure coil applied in the coreless stator is proposed and studied to improve the output performance and efficiency of the axial flux permanent magnet (AFPM) machine. In which the effective conductor is changed to be wedge-shaped by the rolling technology so that the turns of coils and filling factor can be further increased, and the ends are kept in the cylinder with a larger diameter to reduce the DC copper loss. Meanwhile, the air region between the double rotors of the machine is also modified to be wedge-shaped, which fully matches the proposed coils and shortens the air gap length. The advantages of performance can be verified by the three-dimensional (3D) finite element analysis (FEA) and analytical method so that the output characteristics of no-load and load can be improved, and the DC copper loss and eddy current loss of coils can be reduced. The coreless AFPM machine finally performs a high efficiency of 95.34% according to these valuable optimizations.
... In Ref. [67], a multilayer winding arrangement was proposed to eliminate the non-torque producing MMF components for a coreless AFPM machine. In Ref. [123], a hybrid method was discussed for calculating the performance of a coreless stator AFPM generator with overlapping concentrated winding. ...
In recent years, coreless axial‐flux permanent‐magnet (AFPM) machines have been gaining attention. Being coreless, these machines do not experience eddy current (hence hysteresis losses) and has lower cogging torque leading to higher efficiency. However, limitations such as high leakage flux and weak mechanical structure impede its wide application. The results of a systematic review on coreless AFPM machine research is presented, wherein a total of 123 studies have been selected through the Preferred Reported Items for Systematic Reviews and Meta‐Analysis (PRISMA) protocol. About 55% of the articles have been published between 2017 and 2021, indicating recent attention of the researchers on coreless AFPM machines. More than 70% (87 out of 123) of the records have been published by IEEE, which proves the quality and acceptance of the studies. In two‐thirds (77 out of 123) of the studies, single‐stator double‐rotor has been adopted as the machine topology, and in 71.8% (84 out of 123) cases, trapezoidal shape magnets have been used in conventional array. The key research areas on coreless AFPM identified through this review are to produce an efficient design for multiphase and multi‐stage topology and develop lightweight rotor and stator structures.
... 3,4 In recent years, due to the development of materials science, such as rubidium magnets, the power-to-weight ratio of motors has begun to increase rapidly, which makes the power-toweight ratio of hydraulic components, especially for axial piston pumps, have higher challenges. 5,6 The main method of axial piston pumps to increase the power-to-weight ratio is to increase the rotational speed. 7 When the load pressure and the required flow rate are constant, the increase in the rated rotational speed of the pump can reduce the displacement of the pump, thereby increasing the power-to-weight ratio by reducing the weight of the pump. ...
In order to solve the limitations of the friction pairs in axial piston pumps on rotational speed and mechanical efficiency, a 2D piston pump whose 2D piston has two-degree-of-freedom motions of rotation and reciprocating motion was proposed by the author team. The volumetric efficiency of 2D pumps predicted by the original volumetric efficiency model is higher than the experimental results. A new mathematical model of the volumetric efficiency is researched by considering effect of clearance between the cone roller and the guiding rail. In previous studies, the volumetric losses of the 2D pump were considered to be composed of leakage and compressibility loss. However, it is found that the effect of the clearance on the volumetric efficiency in 2D pumps is greater than that of leakage and compressibility loss. The experimental results show that the difference between the prediction of the new model and the volumetric efficiency of the tested pump with 0.19 mm clearance is reduced from 8% to 1.5% comparing with the original model. The volumetric efficiency of the tested pump without the clearance is 96.5% at 5000 rpm rotational speed and 8 MPa load pressure.
... Generators in this class of applications typically have a cylindrical rotor with surface-mounted magnets, but axial magnetic flux disc generator solutions are also very popular [7,8]. For this reason, both design and mathematical modelling techniques of these machines are being constantly developed and improved [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. The Axial Flux PM (AFPM) generator deserves special attention due to their variety of designs and popularity in low-power home applications. ...
... Mathematical models of PM synchronous generators should provide the possibility of solving, in a relatively simple manner, various operational issues associated with the generation of electrical energy. For this purpose, the most suitable are so-called circuit models, commonly used in conventional machines [9][10][11][12]16,22] and the purpose of this paper is to extend the mathematical modeling methodology for this specific class of machines, i.e., axial flux PM synchronous generators operating in steady state. ...
In this paper, an application of the Harmonic Balance Method (HBM) for analysis of Axial Flux Permanent Magnet Generator (AFPMG) is carried out. Particular attention was paid to development of mathematical model equations allowing to estimate the machine properties, without having to use quantitative solutions. The methodology used here allowed for precise determination of Fourier spectra with respect to winding currents and electromagnetic torque (both quantitatively and qualitatively) in steady state operation. Analyses of space harmonic interaction in steady states were presented for the three-phase AFPMG. Satisfactory convergence was between the results of calculations and measurements which confirmed the initial assumption that the developed circuit models of AFPMG are sufficiently accurate and can be useful in the diagnostic analyses, tests and the final stages of the design process.
