Modeling, analysis and design of electromechanical systems
Amirhossein Koushki; Zahra Nasiri Gheidari
Abstract
Coreless Permanent Magnet (CPM) machines are increasingly used in many industrial applications, such as automotive and aerospace applications, wind turbines, medical equipment, robotics, servo drives, and so on. In coreless permanent magnet DC machines, the rotor has a coreless winding structure and ...
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Coreless Permanent Magnet (CPM) machines are increasingly used in many industrial applications, such as automotive and aerospace applications, wind turbines, medical equipment, robotics, servo drives, and so on. In coreless permanent magnet DC machines, the rotor has a coreless winding structure and due to the absence of an iron core, the permanent magnet plays a significant role in these machines. Also, the shaft’s material can change the flux distribution and is another effective parameter on machine performance. Thus, in this paper, a typical coreless PMDC brushed machine is simulated and the effects of magnetization direction and the amount of the residual flux density of permanent magnet, and also the influence of ferromagnetic and non-ferromagnetic material of the shaft on machine performance, are studied and analyzed through three-dimensional finite element analysis. The results show that using a ferromagnetic shaft with a diametrical magnetized permanent magnet can improve the machine's performance in motor mode.
Modeling, analysis and design of electromechanical systems
Amin Nobahari; Antti Lehikoinen
Abstract
Finite element (FE) method, is the most popular numerical approach to low-frequency electromagnetic modeling, especially in the field of electrical machines. Although FE method is nowadays widely used by experts, still it can find widespread efforts toward additional developments that make it more applicable ...
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Finite element (FE) method, is the most popular numerical approach to low-frequency electromagnetic modeling, especially in the field of electrical machines. Although FE method is nowadays widely used by experts, still it can find widespread efforts toward additional developments that make it more applicable to various problems. This paper takes a look at the state of the arts in the electromagnetic modeling of electrical machines via FE analysis. The addressed subjects cover new techniques for loss calculation in electrical machines, the state of art toward more efficient computation, which is a serious challenge for numerical methods, and modeling efforts for the hysteresis phenomenon. The paper tries to address a portion of the recent hot topics of FE analysis of electrical machines. The authors believe that the paper will give a brief but useful insight into the challenges and developments of FE applications in electrical machine analysis, as the most practical numerical tool in this area.
Modeling, analysis and design of electromechanical systems
Hamed Tahanian; Ahmad Darabi
Abstract
Magnetic hysteresis affects the performance of electromagnetic devices, e.g., motors, generators, and transformers. However, due to complex, non-linear, and multi-valued nature of this phenomenon, its accurate coupling to Finite Element Analysis (FEA) of these devices has been always a challenging task. ...
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Magnetic hysteresis affects the performance of electromagnetic devices, e.g., motors, generators, and transformers. However, due to complex, non-linear, and multi-valued nature of this phenomenon, its accurate coupling to Finite Element Analysis (FEA) of these devices has been always a challenging task. A novel approach has been presented in this paper for linking FEA to the Preisach model, which is known as the most accurate hysteresis model. An individual Preisach module has been considered for each field component of each element of the hysteresis material mesh. Hysteresis characteristics between each two successive time steps have been linearly approximated. An iterative algorithm has been proposed for obtaining field distributions along with parameters of these lines, simultaneously. The proposed method has been applied to a general magnetic circuit to predict its behavior over a given time span. Space distributions of flux density at some time steps, time variations of flux density and field intensity for one element, induced voltage, and hysteresis characteristics for some elements have been obtained. In contrast with most previous works, approach of this paper could reflect the details of hysteresis phenomenon, including minor loops, into the FEA. Also, it is applicable to problems with non-uniform and rotating field distributions.
Modeling, analysis and design of electromechanical systems
Mehdi Aliahmadi; Alireza Ghaempanah; Javad Faiz
Abstract
Increasing loading without comparable change in the size of synchronous generators, causes end-winding force estimation become important. Therefore, design of an appropriate support to protect windings deterioration and damages by the above mentioned forces is critical. In slot-embedded portion of coils, ...
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Increasing loading without comparable change in the size of synchronous generators, causes end-winding force estimation become important. Therefore, design of an appropriate support to protect windings deterioration and damages by the above mentioned forces is critical. In slot-embedded portion of coils, the forces could be adjusted by teeth and slot wedges. Normally, the ends of coils have no external support and it is necessary to provide it. Synchronous generators have been considered reliable if accurate end winding forces are evaluated and taken into account in the design process of the external support. The topic based on the current literature is reviewed. Structure of end windings and different analytical and numerical techniques for forces estimation are discussed. The current state of the art is reviewed and more successful developments are introduced. At the end, the area of research which needs more attention in the future to advance the subject is identified.
Modeling, analysis and design of electromechanical systems
Alireza Sheikhi Fini
Abstract
Iran is one of the known countries that has unfavorable energy efficiency, therefore the policy makers of the country have put the correction of this situation on the agenda. This paper has been compiled to review and study the basics of the road map for the development of high-efficiency building technologies ...
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Iran is one of the known countries that has unfavorable energy efficiency, therefore the policy makers of the country have put the correction of this situation on the agenda. This paper has been compiled to review and study the basics of the road map for the development of high-efficiency building technologies and to present a picture of the current state of these technologies in the country. In this paper, the necessity and importance of these technologies and the necessity of developing a road map for this development are expressed. Gathering all the upstream documents in the field of these technologies, the current state of the technology and its characteristics, actors and stakeholders are examined. The strengths and weaknesses in the country for the development of energy-efficient technologies in the building sector have been identified, then the threats and opportunities caused by external factors (outside the country), which stand in the way of the development of energy-efficient technologies in the building sector inside the country, has been studied. A drawing of the existing situation is also provided. This article is useful and effective for policymakers and planners, managers and officials, researchers and academics, industrialists and builders, and in other words, all stakeholders in the field of electricity industry.
