International Journal of Applied Electromagnetics and Mechanics - Volume 57, issue S1

Authors: Ennassiri, H. | Benhamida, M.A. | Amara, Y. | Barakat, G. | Paulides, J.J.H. | Encica, L.

Article Type: Research Article

Abstract: This paper presents a summary of a vibrational behaviour investigation of a 27 slots/24 poles combination surface mounted synchronous electric motor. To achieve this investigation, first, an electromagnetic analysis is done using a quasi 3D finite element model allowing to consider the rotor skewing and to compute the machine magnetic quantities. Second, a modal analysis is done using a 3D FE structural model in order to compute the motor natural frequencies for two cases of contact (Prefect and Adjusted), which are correlated with the magnetic pressure harmonics to extract the possibly excited modes and to show the contact coefficients influence …on the overall results. Third, a structural mechanical analysis under static magnetic loads is done, in which the vibrational response for each harmonic of the magnetic pressure is computed in order to determine which harmonic is responsible of high order displacements. Finally, a structural mechanical analysis under time varying magnetic loads is done to compute machine’s vibrational response for a chosen operating speed using the corresponding local magnetic forces distribution. Show more

Keywords: Vibration, noise, magnetic pressure, natural frequencies, contacts coefficients

DOI: 10.3233/JAE-182302

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 95-106, 2018

Authors: Germishuizen, Johannes | Tanner, Ronald

Article Type: Research Article

Abstract: It is a well-known fact that motor parameters must be accurately known when it comes to designing the inverter control for variable-speed drives. Due to the nonlinear characteristics caused by cross-coupling and saturation effects, calculating inductances – and in particular the magnetic flux of synchronous motors – isn’t straightforward. This paper presents a numerical and stable method to accurately calculate the inductances from the two-dimensional motor characteristics.

Keywords: Cross-coupling, saturation, inductances, synchronous motors, partitioning

DOI: 10.3233/JAE-182300

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 107-114, 2018

Authors: Gonçalves, Bárbara Mara Ferreira | Afonso, Márcio Matias | da Rocha Coppoli, Eduardo Henrique | Ramdane, Brahim | Marechal, Yves

Article Type: Research Article

Abstract: In this paper, the Mixed Finite Element and Natural Element (Mixed FEM-NEM) Method is applied to determine the flux distribution in magnetic devices using its reduced magnetic circuit models. In this solution, the NEM is applied exclusively in the gap of the devices where deformations of the mesh are expected in case of movement and the FEM is applied in the remainder magnetic circuit. In order to reduce the computational cost, the use of anti-periodic boundary conditions is proposed allowing the reduction of the entire domain model. To show the effectiveness of the proposed methodology, the problem is solved by …using FEM and NEM in separate, and by the mixed FEM-NEM. The obtained results are compared using an error estimator and the computational cost. Show more

Keywords: Magnetic flux, reduced magnetic circuit model, Mixed FEM-NEM Method, anti-periodic boundary condition

DOI: 10.3233/JAE-182314

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 115-124, 2018

Authors: Hong, Do-Kwan | Jeong, Yeon-Ho | Woo, Byung Chul | Kim, Tae-Ho

Article Type: Research Article

Abstract: The ETC (Electric Turbo Charger) consists of high speed PMSM, ball or air foil bearings, impeller and controller and so on. KERI (Korea Electrotechnology Research Institute) is developing a high speed surface permanent magnet (SPM) type of synchronous motor and a PWM-driven inverter. This system operates at a power density of 3 kW at 100,000 rpm and is intended to fit the 1,600 cc diesel vehicles to reduce turbo-lag within 0.5 sec. This technology also virtually eliminates turbo lag and enables engine downsizing without compromising engine performance. The design and analysis of the PMSM for the ETC has been developed …successfully considering the electric and mechanical performance using multi-physics analyses. Show more

Keywords: Carbon fiber reinforced plastic (CFRP), iron loss, surface permanent magnet type synchronous motor (PMSM), critical speed, separation margin, turbo lag, electric turbo charger (ETC), eccentricity, forced vibration analysis, acoustic analysis

DOI: 10.3233/JAE-182303

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 125-133, 2018

Authors: Jagiela, Mariusz | Kulik, Marcin

Article Type: Research Article

Abstract: The effects of composite motion involving action of torsion and axial moment on the vibrating element on characteristics of a new cantilever-type nonlinear electromagnetic vibration energy harvester are analyzed. The systems with softening and hardening action of the magnetic force are analyzed. The impact of the phenomenon on electromagnetic quantities of the system is investigated using the 2d analytical and 3d numerical models. The simulated and measured frequency-response characteristics show noticeable differences when the phenomenon is taken into account.

Keywords: Energy harvesters, mechanical vibrations, electromagnetic systems, nonlinear systems, forces

DOI: 10.3233/JAE-182304

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 135-142, 2018

Authors: Januszkiewicz, Łukasz | Di Barba, Paolo | Hausman, Sławomir

Article Type: Research Article

Abstract: In this paper the optimization method and example for a wireless body area network is presented. The optimization goal is to improve the performance of the body area sensor network with respect to the on-body transmission channel and the off-body link performance jointly. The position of the two nodes of the network on the user’s trunk are the design variables. The objective function used in the design process includes two components: one which controls the on-body data transmission between the 3 sensor nodes and another controlling the off-body transmission between the nodes and the remote receiver. The optimization procedure utilizes …a low-cost EStra which is an evolutionary strategy optimization algorithm linked with finite-difference time-domain method based XFdtd electromagnetic simulator. Considering the two on-body and off-body components, the objective-alternance approach applied in this research yields a solution of the problem that compromise between on-body and off-body optimal solution. Show more

Keywords: WBAN, wearable antenna, FDTD, evolutionary optimization algorithms, computational electromagnetics

DOI: 10.3233/JAE-182305

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 143-154, 2018

Authors: Kato, Masayuki | Hirata, Katsuhiro

Article Type: Research Article

Abstract: Authors have proposed an electro/mechanical resonance method to improve characteristics of a linear resonant actuator. However, a reverse current caused by high capacitor voltage was not considered in the finite element analysis. In this paper, we evaluate dynamic characteristics through a modified analysis method in which a reverse current is considered and the validity is confirmed by comparing with measured results.

Keywords: Linear oscillatory actuators, reverse current, electrical resonance, mechanical resonance, linear resonant actuators, finite element method, electromagnetic actuators

DOI: 10.3233/JAE-182306

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 155-163, 2018

Authors: Kurihara, Kazumi | Kurihara, Naoki | Kubota, Tomotsugu

Article Type: Research Article

Abstract: The hysteresis motor produces the torque by magnetic hysteresis. The short-duration overexcitation of the hysteresis motor running at synchronous speed reduces the stator current and increases the pull-out torque at the same time. This excellent effect after one-time overexcitation lasts theoretically forever. However, the sudden changes of stator voltage or load torque reduce and vanish it. The duration time of the effect after one-time overexcitation has not been clear in the continuous operation without stator voltage or load torque changes. We used the three-phase balanced voltage source and measured the duration time after one-time overexcitation under no changes of the …stator voltage and load torque. It was found that the effect by one-time overexcitation lasted for two weeks of the experimental period. It seems that the effect will last forever. It is clear that electric power saving operation of the hysteresis motor using short-duration overexcitation is quite useful. Show more

Keywords: Electric power saving operation, short-duration overexcitation, hysteresis motor

DOI: 10.3233/JAE-182309

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 165-170, 2018

Authors: Lanciotti, N. | Ojeda, J. | Gabsi, M. | Boukhobza, T.

Article Type: Research Article

Abstract: The aim of this study is to analyze the vibration behavior of a five-phase flux switching machine in order to detect and discriminate full and partial open-phase faults. To achieve our goal, radial magnetic stress was calculated by two magnetic models. The first magnetic model, presented in this paper, is obtained by finite element analysis (FE) and the second one by permeance network analysis (PN) of the studied electrical machine. Stator radial accelerations were evaluated coupling each of the two magnetic models with an analytical mechanical model. The results of two multiphysics models are compared with experimental results, in …order to validate them. Experimental measurements are performed under healthy and faulty conditions, at fixed rotational speed. For faulty conditions, full open-phase and partial open-phase fault of the stator winding were analyzed. Show more

Keywords: Vibration behavior, multiphysics models, multiphase flux switching machine, open-phase fault discrimination, experimental validation

DOI: 10.3233/JAE-182310

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 171-178, 2018

Authors: Lowther, David A.

Article Type: Research Article

Abstract: The design of low frequency devices relies on the existence of models which can allow a designer to estimate the performance of a proposed device before it is actually constructed. The advances in information processing hardware have enabled more detailed simulations to be developed but these do not provide the interactivity required for a true design process. The paper discusses the needs of the design process and the difficulties of using computer simulations to create real-world solutions to design problems. Several alternate ways in which the increased computational power can be used to enhance the design process are suggested.

Keywords: Electrical machines, simulation, design systems

DOI: 10.3233/JAE-182312

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 179-190, 2018

Authors: Majer, Krzysztof

Article Type: Research Article

Abstract: This paper presents a method for specifying the magnetizing current of the transformers operating with different submagnetizing of DC flux and for different values of supply voltage (flux density in the core). The theoretical method of calculating of magnetizing currents has been developed. The computation and corresponding measurements were performed for single phase and three phase, three and five legs transformer cores. The influence of magnetization characteristics on the shape of instantaneous current value was investigated. The results obtained were used to determine the peak values of flux density in certain parts of the magnetic circuit. This has a significant …impact on precisely determine vibroacoustic parameters and losses in particular sections of the magnetic circuit of transformers. Show more

Keywords: Transformers, magnetizing current, flux density, submagnetizing

DOI: 10.3233/JAE-182313

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 191-200, 2018

Authors: Pietrzak, L. | Wiak, S. | Smolka, K. | Szymanski, L. | Kolacinski, Z. | Raniszewski, G. | Was, L.

Article Type: Research Article

Abstract: Nowadays there are growing need of energy in every aspect of human living. That is the reason of searching for a highly efficient sources of energy. Supercapacitors or ultracapacitors (how supercapacitors are also described) can be used as ones. Main reason is high energy and power density of those devices. The possibility of using supercapacitors grow along with a reduction in their size while maintaining the above mentioned parameters. Accomplishing of that goal imposes the use of modern materials especially nanomaterials during supercapacitors manufacturing. One of materials recently raising scientists’ interest, as material for ultracapacitors electrodes are carbon nanotubes (CNTs). …It is due to the great electrical and mechanical properties and high specific surface. This article presents results of parameters calculation based on finite element method, obtained for supercapacitors models. In the described models used for simulation, electrodes are made of carbon nanotubes, obtained by synthesis using LSCVD method. Show more

Keywords: Supercapacitors, carbon nanotubes, finite element method, energy sources

DOI: 10.3233/JAE-182315

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 201-207, 2018

Authors: Psuj, Grzegorz

Article Type: Research Article

Abstract: The use of electromagnetic nondestructive testing methods to assess damage and fatigue changes is a subject of numerous studies. However, the observed signals are influenced by many factors. Thus, making a proper assessment on the basis of single parameters’ behavior is complicated task. Therefore, in this paper, an approach of multiple parameters fusion for evaluation of damage was presented. The range of material changes in steel sample after successive stages of fatigue process was monitored using Magnetic Barkhausen Noise and AC magnetization method in a selected two-dimensional region. The acquired data was then processed for the need of signals parametrization. …The procedures in time, frequency and time-frequency domains were applied. Then the selection of representative features was carried out before the information was combined via multivariate regression. Finally, the obtained function was used to achieve the two-dimensional maps of evaluated damage for successive fatigue periods. Show more

Keywords: Fatigue evaluation, nondestructive evaluation, magnetic Barkhausen noise, AC magnetization method, multi-source data fusion

DOI: 10.3233/JAE-182316

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 209-216, 2018

Authors: Wiltuschnig, I.P. | Eckert, P.R. | Flores Filho, A.F. | Dorrell, D.G.

Article Type: Research Article

Abstract: The study in this paper compares three permanent magnet (PM) brushless AC machine topologies with external rotor configuration, which are attractive for in-wheel electric drive applications. All machines use the same stator but have different rotor geometries: a conventional surface PM structure, a surface quasi-Halbach PM array structure, and an interior V-shaped PM structure. For these topologies, the volume of the PM material is the same. A numerical simulation based on finite element analysis was carried out for the three cases to evaluate and compare their behaviour in terms of torque density, magnetic flux density, and torque ripple.

Keywords: Brushless motor, external rotor, interior magnets, permanent magnets, quasi-Halbach array

DOI: 10.3233/JAE-182299

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 217-225, 2018

Authors: Yamaguchi, Tadashi | Kawase, Yoshihiro | Asai, Hirofumi | Shibata, Masahide | Toida, Naotaka | Furukawa, Tomoyasu | Kawano, Hiroshi

Article Type: Research Article

Abstract: In this paper, we analyze the interbar current taking into account of the contact resistance between the secondary conductor and the steel sheets of squirrel-cage induction motors using the 3-D parallel finite element method. As a result, the effects of the contact resistance on the interbar current are clarified.

Keywords: 3-D parallel finite element method, squirrel-cage induction motor, interbar current, contact resistance, skew

DOI: 10.3233/JAE-182307

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 227-233, 2018

Authors: Zajac, Mieczysław | Sułowicz, Maciej

Article Type: Research Article

Abstract: The subject of this work concerns the problem of signal diagnostics of induction machines carried out in the time-and-frequency domain. It was assumed that the signal carrying the important information about the current state of the machine is the measured signal of the axial flux. The basis for the diagnostic decision making was the analysis of the energy of the detailed wavelet representation, obtained as a result of the use of a specially constructed orthonormal transformation basis. To ensure sufficient resolution of fault detection, the authors constructed orthonormal wavelet basis based on the recursive formulas for generating higher order Legendre polynomials. …The construction of the orthonormal basis was carried out using the scaling function, which was designed using the appropriately scaled Legendre polynomial. The synthesis of the basic wavelet and the orthonormal basis was based on the recurrent dependencies of the multi-resolution analysis using the relationship between the elements of the quadrature mirror filters. Dependencies between elements from two consecutive levels of decomposition were used. By applying the constructed orthonormal basis, the research on the nature of the energy flow of an axial flux signal of an induction motor between adjacent frequency bandwidths in steady-state depending on the machine load was presented. Studies have shown that significant flows of the diagnostic signal energy occur between the adjacent frequency bandwidths periodically at frequency of about 2.5 Hz. This periodic energy flows of the axial flux signal hamper fault detection and diagnostic decision making. The analysis results confirmed that it is possible to ensure a sufficient level of selectivity of a diagnostic system by means of this method. To ensure a sufficient efficiency of diagnostic systems it is required to separate flow effects from fault symptoms. Show more

Keywords: Technical diagnostics, induction motor faults, time-frequency analysis, wavelets, orthogonal polynomials

DOI: 10.3233/JAE-182319

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. S1, pp. 235-249, 2018