Search

With the introduction of stricter energy-efficiency-ratio regulations, the surface-mounted permanent-magnet motor (SPM) is gaining increasing attention due to its inherent high-power density. This article investigates the feasible SPM structures for refrigerant compressor applications, particularly those used in metal industry factories with high surrounding temperatures so that cost-effective solutions can be achieved. A theoretical model is first established to aid structural parameter optimizations and the management of specific operational objectives and constraints; multiple SPM arrangements are investigates, with ease of manufacturing implementation being one consideration, as shown in Liu et al., 2021. Detailed finite element calculations and experimental measurements are performed to develop feasible SPMs with optimized structural arrangements that meet the desired operational objectives. [ABSTRACT FROM AUTHOR]

With high surrounding temperatures, winding resistance increases and thus lowers the operational efficiency of a motor. To meet the large application requirements and conform with the ever-increasing energy-efficiency regulations for pump equipment in the metals industry, consistent efforts have focused on producing single-phase motors that can deliver superior performance at a low cost. Because the steady-state rotational speed is synchronized and no driver circuit is required, a direct-on-line synchronous reluctance motor is a potentially viable alternative to the commonly adopted induction motors. Its inherently simple structure and comparably low operational speed necessitate a challenging structural design for accomplishing the high-efficiency objectives of pump applications. These challenges and their potential solutions are reported in detail. By employing a systematic design scheme and including thermal concerns of the performance, a competitive high-efficiency single-phase direct-on-line synchronous reluctance motor for pump applications in various metal industry equipment was offered. [ABSTRACT FROM AUTHOR]

To meet the severe operating conditions in the metal industry, more thorough design and operational assessments about those implemented electric motors for specific applications must be emphasized. With its inherent robust structure, the induction motor is generally adopted to fulfill such driven objective. However, due to global warming and energy conservation concerns, those strictly enforced regulations have potentially increased the complexity and cost of high efficiency induction motor. Since the synchronous reluctance motor (SynRM) has relatively simpler structure with no copper loss in its rotor, it is a very attractive alternative for accomplishing the high-efficiency objectives of those common hoist, punch, roller, and pump applications. In addition, to eliminate drive circuits that can further reduce the overall system construction costs, the rotor barriers of the SynRM can be equipped with direct-on-line capability (DOL_SynRM) with conductors filled in. The impacts to the operational performance of these DOL_SynRMs for different applications will all be thoroughly investigated. The competitive high-efficiency DOL_SynRMs for driving various metal industry equipment can thus be offered. [ABSTRACT FROM AUTHOR]

Demands of appropriate personal mobility‐assistive devices for those needed persons have been increased considerably in recent years, with their specific operational requirements, developments of adequate motors to different device parts are the main concerns. For applications onto those knee joint parts of the exoskeleton system, three types of permanent‐magnet (PM) motors, namely the surface‐mounted PM motor, the Vernier motor, and the flux‐switching motor were designed. Based on the operational and physical constraints of the particular exoskeleton parts, optimisations of these PM motors were provided along with their thorough performance comparisons. From emulated finite‐element analyses along with hardware experimental validations, by following the standard test settings, selection guidance for the suitable motor structures at different operational objectives will thus be supplied. [ABSTRACT FROM AUTHOR]

To meet different loading requirements in the metal industry, special attention must be paid to the operational performances and start-up characteristics of those electric motors implemented for desired driven applications. However, because of the global warming and energy conservation concerns, the enforced operational regulations have increased the complexity of those commonly applied induction motors for supplying the desired equipment driven forces. By adopting the same stator, the synchronous reluctance motor (SynRM) can be achieved with properly redesigned rotor structure of an induction motor. Due to its robust structure and lack of secondary copper loss, it is very competitive for the related hoist, punch, roller, and pump applications. Furthermore, by inserting adequate ferrite permanent magnets and conductors into the rotor barriers, composition designs of the direct-on-line SynRMs (DOL_SynRMs) will also be proposed. The operational characteristics of the DOL_SynRMs for fulfilling different specifications will all be thoroughly investigated and confirmed by experimental measurements. The DOL_SynRM structures that can provide potential alternatives for related high-efficiency metal industry-driven applications can thus be validated. [ABSTRACT FROM AUTHOR]

To meet the higher operational efficiency regulations of electric motors due to energy-conservation concerns, specific design efforts have been dedicated to those motors for different industrial application requirements. Since the synchronous reluctance motor (SynRM) is generally designed based on the same stator structure as that of the induction motor and operated at synchronous speed, whereas no electrical contact to its rotor, it is capable of providing a robust structure and no rotor copper loss. Such features are very attractive for the related hoist, punch, roller, and pump applications that are commonly adopted in the metals industry. By equipping adequate power factor correction and line-start capabilities, the detailed designs and performance analyses of the SynRMs with a common rotor structure composed by laminated electrical steels will be proposed. Based on this common rotor structure, the operational characteristics of the SynRMs for fulfilling different specifications will all be thoroughly investigated. Confirmed by experimental validations, valuable guidance for related SynRM constructions and applications can thus be provided for metals industry and motor designers. [ABSTRACT FROM AUTHOR]

To meet the increasingly stringent regulations on operational efficiencies of electric motors, efforts have been devoted to design and construct motors with less power losses. Without the need of rotor conductors, and hence, no secondary copper loss, the feasibilities of applying synchronous reluctance motor (SynRM) have attracted many attentions on the related industries. Since the operation of SynRM is mainly based on the reluctance torque, appropriate electromagnetic steel selections for the motors will be the key factors. To adequately evaluate the performance of SynRM, with the available magnetization and hysteresis characteristics of the commercial steel sheets, the SynRMs that are composed of different electromagnetic steels at various operational specifications will be thoroughly investigated. From theoretical analyses of the selected SynRMs by different stator and rotor material compositions along with experimental validations, valuable guidance for related SynRM constructions and operations can thus be provided for steel manufacturers and motor designers. [ABSTRACT FROM PUBLISHER]

By appropriately inserting ferrite magnets into the rotor of a synchronous reluctance motor (SynRM), the machine operational power factors and torque outputs can be improved. With specific rotor structures to accommodate those ferrites, many of these permanent-magnet-assisted SynRMs (PMA-SynRMs) have been proposed to comply the expected operational objectives. For construction convenience, the ferrites that being inserted into the flux barriers of these PMA-SynRMs are generally in rectangular shapes; hence, some adjustments on the rotor flux barriers and additional bridges are required. Such changes will inevitably affect the performance of the original SynRMs with optimized rotor structures, and these tradeoffs are thus to be recovered by parts of those adopted ferrites. This paper will provide an evaluation index that can characterize the performance of PMA-SynRMs with different volume compositions of the ferrites, along with the impact assessments of the SynRMs with modified flux barriers such that those ferrites can be properly allocated. Based on the designs obtained from thorough 3-D finite-element analyses, a 3-hp PMA-SynRM will be constructed and the related experimental measurements will also be supported to validate the design adequacies. [ABSTRACT FROM AUTHOR]

To effectively retrieve the inherent vibration energies, feasibility of replacing those common mechanical shock absorbers of the suspension system that are mounted between the wheels and bogie of a motorbike with electromagnetic motion device will be assessed. Instead of consuming additional energies to control the vibration patterns, the main design objectives are to produce the su-spension forces to meet the maximum encountered force specifications and to convert the input mechanical vibrations to electric energies directly. Based on proper emulation designs and electrical output controls, the operational fluxes and dynamic characteristics of this hybrid suspension system at various operational conditions will be thoroughly investigated, and the satisfactory performances of the proposed system can then be systematically validated. [ABSTRACT FROM AUTHOR]

This paper will present the designs and feasibility assessments of a linear electromagnetic actuator that can directly provide the electric power steering (EPS) forces for an economy sized vehicle. Within the physical and operational constraints, a tubular device being composed by a linear permanent magnet motor and a magnetic gears set will be systematically designed to form the coaxially magnetic-geared linear actuator. Determinations of the optimized geometrical compositions of the motor and the gears set based on the fluxes and thrust forces will be assessed in detail. For practical considerations, the dynamic performances of the proposed EPS system and the corresponding radii of turning circles will also be evaluated at various driving speeds. It is thus confirmed that the adoptions of such electromagnetic systems for those common EPS systems are technically feasible. [ABSTRACT FROM PUBLISHER]

To achieve relatively lower costs and higher operational efficiencies, without adopting permanent magnets or rotor conductors, the synchronous reluctance motor (SynRM) has received more and more attentions as a competitive solution recently. To establish a rational guidance for the related designs and constructions, this paper is aimed to present the thorough performance impact assessments of SynRMs that are composed of different electromagnetic steels at various operational specifications. Based on the magnetization and hysteresis characteristics of the steel sheets, variations of the average torques, torque ripples, and iron losses by using different stator and rotor materials are investigated, and some valuable comparison results can be provided for designers and engineers in the related motor and metal industries. [ABSTRACT FROM AUTHOR]

By adopting the analytical model and magnetic equivalent circuit concepts, a systematic scheme that can be conveniently applied for the optimal component composition designs of an integrated tubular linear magnetic-geared machine (TLM2) will be provided. The TLM2 system can be either adopted to generate electric powers or to supply large mechanical thrust forces. With its complex double-mover and coaxial magnetic gear structures, the associated system performance based on different component parameters and arrangements can be rationally and efficiently evaluated. Based on thorough flux coupling designs and 3-D finite-element analyses, the adequacies of the proposed analytical scheme for assisting the optimal TLM2 system design at specified physical constraints can be confirmed. A laboratory TLM2 prototype has successfully been developed to operate as a generator for demonstration, and it is confident that its linear actuator counterparts can also be conveniently and reasonably designed based on the same scheme. [ABSTRACT FROM PUBLISHER]

This paper will present the detailed design and feasibility assessments of a linear electromagnetic actuator for providing the required roll-gap adjustment forces directly. A systematic analyzing scheme will be developed to optimize the system structures within specified physical constraints and steady-state operational requirements. The magnetic fluxes and thrusts that can be provided by the proposed system will be analyzed in detail, and the installation comparisons with those rotary electromagnetic counterparts will be discussed. By considering the desired system response times, the corresponding dynamic operational performances are also investigated. From these investigations, the technical feasibilities of adopting such electromagnetic systems for those commonly used hydraulic cylinder/servo valve compositions in the tandem roll mill can then be confirmed. [ABSTRACT FROM AUTHOR]

With the ever rigorous operational efficiency requirements, effective copper loss reduction is one of the viable approaches for small-power alternative current motors. Among those cost-effective schemes, by eliminating the rotor windings while keeping the same stator structures, the synchronous-reluctance motor (SynRM) offers a potential substitute for those small-power applications that the induction motors are commonly adopted. Since the key factor that affects the SynRM-generated torque will be the difference between its direct-axis and quadrature-axis inductances, by arranging the rotor field paths aligned to the direct axis and by considering the possible cross-coupling magnetic saturations on the rotor ribs and segments, the performance impacts due to field path arrangements on the rotor will be thoroughly evaluated by 3-D finite-element analyses. From the experimental measurements, it is clear that the operational objectives can be achieved, and the adequacy of the proposed design guidance can then be confirmed. [ABSTRACT FROM AUTHOR]

This paper is aimed to provide the detailed design and operational investigations of synchronous reluctance motors (SynRM) that are commonly assembled by laminated electromagnetic steels. The magnetic flux paths in the SynRM rotors with various barrier and segment compositions will be analyzed, along with the generated motor torque and loss assessments. As the related mechanical cutting and/or punching processes on the rotor steels are required to achieve desired direct- and quadrature-axis reluctance ratios, their impacts to the flux paths due to saturations will also be thoroughly evaluated. Assisted by 3-D finite-element analyses, the results clearly indicated that the additional annealing process on the electromagnetic steel strips must be introduced for these SynRM designs with smaller sizes and higher efficiency requirements. [ABSTRACT FROM PUBLISHER]

By properly designing the magnetic fields on top of the target surface, more target atoms can be sputtered and smoother depositions onto the substrate surface can be achieved of a dc magnetron sputter (MS). Based on detailed 3-D field information and appropriate emulation process, the argon ion bombardments to the target surface and collisions to those sputtered target atoms can then be thoroughly evaluated. Therefore, from Taguchi’s method and feasible structural compositions, the optimization objective of designing adequate refinement parts for dc MS can be conveniently achieved. From the experimental measurements, by both the thickness gauge and atomic force microscopy, the enhanced performances of the existing dc MS systems can then be confirmed. [ABSTRACT FROM AUTHOR]

This paper describes design techniques for a doublesided hybrid excited linear flux switching permanent magnet motor to achieve low force ripple while satisfying the required average thrust force. In this paper, we employ auxiliary poles fixed to both sides of the mover and determine the switching signal turn-on angle to reduce the force ripple in the initial design. Then, the sensitivity analysis of two split ratios is conducted to provide a feasible search direction for the optimization process. Finally, a finite-element-based optimization is utilized to minimize the force ripple and to satisfy the required average thrust force. Simulation results are validated by experimental measurement. [ABSTRACT FROM AUTHOR]

With their consistent production line load increments, the possibilities of substation congestion problems in the integrated steel companies are inevitable. To meet these power demands, well-organized system infrastructure expansion plans must be designed in advance. An alternative scheme to alleviate some short-term facility overload problems is to integrate distributed generator units into the system to defer possible congestion. Based on substation operational constraints, systematic guidance for evaluating the optimal location and reliability indices of DG units into the system will be provided for related operations. The proposed scheme can be adopted by steel companies and other industries in determining the installation and integration schedule of DG units and thus defer the required expansions of substation infrastructures. [ABSTRACT FROM PUBLISHER]

By adopting the double-rotor structure and the coaxial magnetic gear concept, a permanent magnet (PM) generator is proposed for harvesting the wind energy directly without mechanical conversions. In addition to the physical model realizations, this paper will present the detailed design and implementation concerns of the magnetic-geared double-rotor PM generator along with thorough loss assessments. The comparisons of PM magnetization directions and arrangements, the selections of proper windings, and the operational efficiencies of this machine along with the terminal voltage phase shifts due to different loading conditions will all be summarized. The realization process of a portable 2.5-kVA generator that can be directly coupled to the mechanical driven source without additional mechanical gears will be demonstrated, and the feasibility of such a machine structure can certainly be confirmed from the satisfactory performance results. [ABSTRACT FROM PUBLISHER]

With proper adjustments of the magnetic fields inside an existing dc magnetron sputter (MS), trajectories of those argon electrons in the vacuum chamber can be further confined and the racetrack erosion patterns on the target surface can be better controlled. Hence the target can be more effectively utilized and the system sputtering rate can also be enhanced. By implementing appropriate passive iron annulus and active compensation magnetizations onto the dc MS, based on Taguchi’s method, three typical reference target erosion patterns are selected for verification. From the promising emulation results, it can be demonstrated that these target erosion patterns can be precisely controlled to the designated profiles and more electron trajectories can be confined, hence the objectives of designing structural refinements for better the dc MS performance can be confirmed. [ABSTRACT FROM PUBLISHER]

This paper presents a procedure for determining the winding layout for the design of high performance flux switching permanent magnet (FSPM) machines with concentrated windings. Three winding configurations, namely, single-layer, double-layer and multilayer windings are illustrated. A comparison of the electromagnetic performance of the three winding configurations is made using finite element analysis. It may provide a useful reference to be considered in the FSPM machine design. [ABSTRACT FROM PUBLISHER]

This paper deals with the optimal design of surface-mounted permanent magnet motors for use in a high speed spindle machine tool in glass grinding applications. We apply the Taguchi method to refine the stator structure and use segmented rotor magnets for the motor to yield the desired performance. A thermal analysis is conducted to obtain the temperature distribution within the motor. We examine the results using finite element analysis and validate them by experimental measurements. [ABSTRACT FROM PUBLISHER]

To design a stable and fully controllable process for conveying steel plates with less noise, we have extensively investigated the feasibility of incorporating the structure that can provide appropriate extra electromagnetic attraction forces. By implementing appropriate fixed electromagnetic poles on top of the rollers at the run-out table of a steel mill, controllable lift and propulsive forces can thus be provided to drive the movable steel plate to the desired 2-D directions. Based on the stringent operational environment at a steel mill, an online recursive gap detection scheme combined with a real-time fuzzy-based controller has been developed. Realization results showed that the system, being implemented with the proposed fine-tuned processing/control scheme, can supply rapid and accurate online 2-D controls onto the steel plates and thus fulfill the design and operational objectives. [ABSTRACT FROM AUTHOR]

This paper describes a technique to minimize the use of rare-earth magnets in surface mounted permanent magnet (SPM) motors, while still meeting the specifications of the motor. The method is based on calculating the no-load flux linkage in the stator winding in terms of a volume integral applied to the volume of the PM inside the machine. We apply it to three SPM motors equipped with integral-slot windings. Both finite element analysis and experimental results show that this technique can not only improve the machine performance but also reduce the use of magnets while still maintaining the required value of average torque. [ABSTRACT FROM AUTHOR]

This paper describes a design optimization based on the fuzzy-based Taguchi method coupled with finite element analysis (FEA). The proposed approach takes advantage of both the Taguchi method and a fuzzy rule based inference system, which forms a robust and practical methodology in tackling multiobjective optimization problems. The proposed methodology is applied to the optimization design of a surface-mounted permanent magnet (SPM) motor. The experimental results confirm the validity of the proposed method. [ABSTRACT FROM PUBLISHER]

To investigate the possible performances of electromagnetic steel products before their constructions, adequate assessments of the related losses are required. Without using the detailed finite-element analyses, based on the ideas of common magnetic equivalent circuit and numerical Epstein Frame test circuit, a rational iron loss emulation scheme will be proposed. By properly modeling the possible magnetizing recoil loops, this scheme can process those information on the electromagnetic steel datasheets supplied by the manufacturers directly. Therefore, the detailed hysteresis inner-loop characteristics resulted from product structures and magnetization harmonics can be appropriately modeled, and a reliable and convenient iron loss assessment scheme for the electromagnetic steel products in the design and online operation stages can be established. [ABSTRACT FROM PUBLISHER]

To smooth the substrate depositions of DC magnetron sputter (MS), such that the supplementary electrical and mechanical adjustment efforts can be alleviated, a refinement scheme that can be applied directly to the existing DC MS will be introduced. By properly control the magnetic and electric fields inside the vacuum chamber, trajectories of those atoms that are sputtered from the target surface can be more spread out. In addition, with the resultant higher plasma density, chance of collisions among the sputtered atoms and those Ar ions in the plasma will also be increased, hence the resulting distributions of target atoms deposited on the substrate surface will certainly be even out. To further confirm such concepts, a rational emulating process that can exploring both the atom sputtering process from the target and those collisions at the chamber with different three-dimensional magnetic and electric field environments is also developed. Thus the associated performance investigations on the DC MS with different magnetron arrangements can then be conveniently explored. [ABSTRACT FROM PUBLISHER]

A hybrid excited linear flux switching permanent magnet motor (HLFSPMM) is a possible solution for developing a rare-earth-magnet-free electric motor with high force density. We designed an HLFSPMM that uses a ferrite magnet in place of a rare earth magnet. A suitable mover slot and stator pole number combination was selected in the initial design stage to achieve the desired performance capability. Structural refinements using design sensitivity analysis (DSA) based on the finite element method (FEM) were performed to enhance the machine performance. Simulation results have been validated by experimental measurements. [ABSTRACT FROM AUTHOR]

In this paper, a technique for reducing the cogging force in slotted permanent magnet linear synchronous motors (PMLSMs) is presented. A two-step minimization process that depends on the slotting and end effects is proposed. Taguchi's parameter method, coupled with 2-D and 3-D finite element analysis (FEA), is employed to minimize the cogging force. [ABSTRACT FROM PUBLISHER]

To improve the production qualities of a steel mill, in-mold electromagnetic stirrers (M-EMS) are generally implemented at the continuous casting process to provide the desired stirring forces to remove those undesired inclusions and bubbles during the metal solidification. As the system is mainly operated by interaction of induced eddy currents and composite traveling electromagnetic fields in the molten metal, inputs of stator currents and structures of M-EMS will dominate the entire system performance. Assisted by three-dimensional (3-D) finite-element analysis (FEA) and flux path modeling refinements, a compact analytical model with sufficient accuracy that can adequately predict the time-averaged performance of the M-EMS system at various structure- and material-compositions will be devised. From these confirmed operational indices, a convenient assessment tool for on-site operation and maintenance of the M-EMS at the metal industry has been successfully established. [ABSTRACT FROM PUBLISHER]

This paper presents impacts of different permanent magnet materials and operational temperatures on the performance of interior permanent magnet (IPM) machines for electric vehicle applications. Variations of the average torque, torque ripple, cogging torque, and no-load EMF with different neodymium-iron-boron (NdFeB) permanent magnet materials and operational temperatures are investigated. Based on finite-element method (FEM), performance about the ripple and cogging torques of the IPM machine will be analyzed and some useful conclusions can be provided for researchers and engineers in the related traction motor industries. [ABSTRACT FROM AUTHOR]

Presents information on a study which developed an approach to analyze the characteristics of disc permanent magnet linear synchronous machines (DPMLSM). Significance of improved permanent magnet in electric vehicles; System modeling; Characteristics analyses of DPMLSM; Results of the experiments; Conclusion.

Discusses the development of a multiple reference frame for dynamic analysis and controller design of linear electromagnetic motion devices. Application of vector control schemes to rotary alternating current (ac) machine systems; Significance of the reference frame theory on magnetic field systems; Use of algorithms in system voltage equations.