Search

This paper proposes the design and analysis of a flux modulated (FM) permanent magnet (PM) linear actuator for the long track gantry robot system used to detect fire hazards in an electric energy storage system (ESS). A detailed design framework for the FM-linear actuator inspired by the magnetic gearing effect is proposed which includes the selection of slot-pole pair numbers and assigning optimal geometric parameters based on working harmonic characteristics. Using the optimal model, the electromagnetic performances both under no-load and full load conditions are performed to check the feasibility of the actuator for the gantry system. A prototype is built to validate the results obtained using the 2D and 3D finite element analysis (FEA). [ABSTRACT FROM AUTHOR]

This work presents a coursework design process to study the fugitive dust generation and detection method in South Korean Cities. The work is broadly classified into two parts, namely, designing of a software-based virtual platform to study the fugitive dust generation sites i.e the construction sites in a 3D computational fluid dynamics (CFD) environment and developing a low-cost dust concentration detection sensor to perform the different laboratory-based test within undergraduate coursework. The work also evaluates the effectiveness of the dustproof nets usually used by the construction industry in preventing fugitive dust. A detailed background check in terms of theoretical and legal rules has been studied. Then detailed simulations are performed and finally, the sensor system is developed to perform field tests. [ABSTRACT FROM AUTHOR]

This article proposes a 65 kW rim-driven direct-drive flux concentrated permanent magnet synchronous generator (FCPMSG) used in urban water pipeline energy harvester (UWEH) system. The proposed UWEH system plans to use hydraulic bearing; thus, a balanced radial force topology should be selected with high electromagnetic performance. Considering the hydraulic bearing mechanism and the installation of the proposed PM synchronous generator (PMSG), the effect of the loading and slot harmonics on the radial magnetic forces is analyzed. Furthermore, by studying the effect of the passive and active electric loads on the PMSGs, radial force characteristics are analyzed to select the operation region. [ABSTRACT FROM AUTHOR]

This article proposes the design and driving mechanism of a single drive motor integrated electromechanical actuator system for the application in computer numerical control (CNC) lathe machines. The electromechanical actuator is designed in such a way that it can replace the conventionally used hydraulically powered headstocks of the lathe machine. To achieve a drawbar thrust of 50 kN and a spindle speed of 4000 r/m, a detailed design with an explanation of different internal parts of the electromechanical actuator is presented. The production ready model was simulated to select the safety factor of the whole system and to enquire the amount of deformation when 50 kN thurst is generated. A prototype is manufactured based on the analysis model and is tested for different modes of operation. The experimental results validate the capability of the electromechanical actuator to produce the require drawbar thrust of 50 kN and spindle speed of 4000 r/m. [ABSTRACT FROM AUTHOR]

In this article, the design and characteristic research of the coaxial magnetic gear for the contra-rotating propeller in the premium yacht are presented. The scale-down model of 1/25 is reviewed as the research of the applicability of the coaxial magnetic gear. The space harmonic characteristics of the magnetic field in the coaxial magnetic gear with the low gear ratio from 1 to 2 are investigated, and the optimized models with the surface-mounted permanent magnet and quasi-Halbach array are obtained using the response surface method. In the several operating points of the diesel engine, the magnetic loss and the resultant thermal characteristics are analyzed and compared in each model. Finally, the desired coaxial magnetic for the contra-rotating propeller in the premium yacht is achieved. [ABSTRACT FROM AUTHOR]

This paper proposes two novel airgap profile designs and distributed airgap arrangement scheme for reduction of winding and thermal losses in high frequency current transformer (HFCT) sensors. The novel airgap profiles namely, zigzag and stepped airgap profiles are proposed to reduce fringing flux around the winding conductors. Moreover, to decrease winding and thermal losses, distributed airgap arrangement scheme is proposed. In distributed airgap arrangement, a single airgap is distributed to multiple equidistant smaller airgaps around the magnetic core. The analysis is performed using 3D finite element analysis (FEA) method. The 3D-finite element analysis results confirm that the HFCT sensors with the proposed airgap profiles and arrangement scheme can reduce winding and thermal losses ensuring high performance for HFCT sensors. [ABSTRACT FROM AUTHOR]

Recently, the permanent magnet vernier machine (PMVM) is studied extensively because of its merits such as the high torque density. Similar to the magnetic gears, the PMVM operates on the principle of flux modulation. However, there is a distinct difference in between the two as unlike the magnetic gear, in case of PMVM, the winding MMF harmonics rotates with different speed as that of the fundamental. As a result, these harmonics are capable of making a working magnetic field by interacting with different permeance harmonics. Therefore, this paper aims to provide an analytical explanation of this whole process, which is helpful to understand the effect of the flux modulation on the output torque. Furthermore, using the analytical formulation, this work finds the optimal geometric parameters which maximize the working magnetic field and hence the torque. A detailed analysis of the PMVM with the doubly salient structure is studied and the performance is analyzed using the finite element method (FEM) and the experimental setup. The FEM and experimental results verify the maximum torque production by using the optimal geometric parameters in the PMVM modeling, obtained using the analytical formulation. [ABSTRACT FROM AUTHOR]

This paper proposes the design of a linear magnetic position sensor (LMPS) to detect the mover position of the permanent magnet linear synchronous machines (PMLSMs). The working principle of the LMPS is based on the well-known Hall-Effect. The Hall-Effect-based design of LMPS is considered because it provides a low cost and relatively harsh environment susceptible alternative for the position detection for long track PMLSM system. The initial design was performed using 3D-finite element analysis and genetic algorithm-based deterministic optimization. Based on the initial model, four LMPS were manufactured and tested under the output constraint of peak flux density > 0.1T and total harmonic distortion < 3%. From the test results, it is concluded that the manufactured LMPS suffered significant deviation in output compared to the simulation model. These anomalies arise because of the manufacturing tolerances. To further improve the design and manufacturing process of the LMPS considering the effect of tolerance, a reliability-based robust design optimization (RBRDO) of the LMPS is proposed. The results of RBRDO confirms its usefulness for the design process of the LMPS in terms of undesired design non-compliance cost and great robustness without sacrificing the accuracy of the output signal. [ABSTRACT FROM AUTHOR]

Unlike the coaxial magnetic gear (CMG), the magnetic geared machine (MGM) has the ac armature winding on the inner part or the outer part. Besides, the PM excitation field of the CMG and the ac armature field of the MGM have different space harmonic components of magnetic field from one other. Hence, the flux modulation characteristics in the CMG and the MGM are different, and the resultant magnetic radial forces at the modulating pieces are also occurred differently from one another. Thus, in this paper, first, the flux modulation characteristics of the PM excitation field in the CMG and the ac armature field in the MGM are presented. Second, the characteristics of the magnetic radial forces at the modulating pieces are analyzed, and the causes of the radial force according to the space harmonic components of the magnetic field are compared in the CMG and the MGM. [ABSTRACT FROM AUTHOR]

The problem of the computationally efficient analysis of the electromagnetic system with nonlinearity is considered in the proposed work. Unlike the previously proposed proper orthogonal decomposition (POD)-based model order reduction (MOR), the proposed method based on the dynamic mode decomposition works well even under the highly nonlinear system. Using the proposed method, a highly saturated interior permanent-magnet (IPM) motor model is analyzed. Comparisons in terms of the radial air-gap flux density and torque are made with that of the full and POD-based models. The results show that the proposed method is capable of giving a good approximation of the full model of the IPM motor. Also, a reduction in the computational time can be achieved compared with that of the traditional POD-based MOR. [ABSTRACT FROM AUTHOR]

This paper presents a novel parametric design analysis of the magnetic sensor module used to find mover positions in linear motors. The proposed framework utilizes a computationally inexpensive proper orthogonal decomposition-dynamic mode decomposition-based model order reduction (MOR), coupled with a multiparameter moment matching method. The model is then utilized by a moment-based probabilistic design optimization method that considers the manufacturing uncertainties to find the optimal sensor design. A magnetic sensor module is designed for employing the proposed framework, and the results show that: 1) the proposed MOR technique is accurate; 2) the reliability analysis performed during the probabilistic design optimization can help to reduce the excessive non-compliance costs for the manufacturers; and 3) the combined framework is able to significantly expedite the optimal design search. [ABSTRACT FROM AUTHOR]

This paper investigates the vibration and noise characteristics of the coaxial magnetic gear (CMG) by the electromagnetic forces. In the CMG, the vibration and noise can be generated by the exciting forces acting on three parts, namely, low-speed rotor, high-speed rotor, and modulating pieces, respectively. The electromagnetic forces acting on three parts of the CMG and their force frequencies are calculated by using the Maxwell stress tensor method. Also, the mode shapes of the CMG full model and their resonance frequencies are obtained by the modal analysis. Through the electromagnetic forces and the result of the modal analysis, the vibration calculation is performed by using the 3-D-finite element method. Then, the effect of displacement on noise is confirmed by comparing the vibration calculation data and experiment data. The result shows the most affected part among the three parts of the CMG due to the noise is the low-speed rotor. [ABSTRACT FROM AUTHOR]

This paper investigates the characteristics of the radial force density according to the shapes of the flux modulation poles (FMP) in a surface-mounted vernier machine (SPMVM). The air-gap flux density harmonics obtained from the finite-element analysis method are analyzed using the analytical equations derived from the magnetomotive force and the air-gap permeance distributions. Then, in order to find the radial force density harmonics that generate the exciting force on the stator, the spatial orders and the angular frequencies of the radial force density harmonics are calculated by using the Maxwell stress tensor method. The analysis results show that the permeance harmonics generate the radial force density harmonics, but the resulting harmonics of the radial force density are time-invariant in the spatial domain. Consequently, the variation of the FMP shape can improve the torque characteristics of the SPMVM without the increase of the exciting force on the stator core. [ABSTRACT FROM AUTHOR]

This paper presents an accurate initial pole position (IPP) estimation method for a surface mounted permanent magnet synchronous motor (PMSM) without the use of pole sensors. To estimate the IPP, the proposed method uses the concept of reference frame. In this method, three torque commands, separated by 45° electrically from each other, are applied to the PMSM. Using the reference torque commands, moving distances are measured and transformation matrix is applied to eliminate the load torque term. Finally, the IPP is determined using the secant method. The IPPs under no load and at specific loaded condition are measured. The result of the load condition is compared with the previously proposed two reference frame method. The proposed method gives better result under load condition, compared with the two reference frame method, which fails to give satisfactory result under load condition. [ABSTRACT FROM AUTHOR]