International Journal of Applied Electromagnetics and Mechanics - Volume 55, issue 4

Authors: Zhang, Ju-Qiu | Liang, Zhi-Shan

Article Type: Research Article

Abstract: High-altitude electromagnetic pulse can couple oil-gas pipeline systems to cause damage to electronic equipments. In order to study the effects of high-altitude electromagnetic pulse on buried pipeline, the differential equations for high-altitude electromagnetic pulse coupling buried pipeline are derived based on Maxwell’s equations. The coupling equations are solved in frequency domain, and then the induced current and voltage waveforms are obtained by using inverse Fourier transform. The currents and voltages at both ends and in the middle of pipeline are calculated. It is shown that the peak values of the currents along the pipeline don’t vary much. The voltages at …both ends of the pipeline are larger and the voltage polarity at one end is opposite to another, while the voltages in the middle of the pipeline are smaller. Finally, the effects of system characteristics on induced currents are presented, such as the length of the pipeline, the depth of the pipeline, the radius of outer surface of the pipeline and the conductivity of the ground. The results of these studies are applicable to electromagnetic pulse protection. Show more

Keywords: High-altitude electromagnetic pulse, buried pipeline, coupling equation, induced current, induced voltage

DOI: 10.3233/JAE-160141

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 507-522, 2017

Authors: Sun, Xiaodong | Shi, Zhou | Wang, Shaohua | Chen, Long | Yang, Zebin | Li, Ke

Article Type: Research Article

Abstract: Aimed at enhancing the control precision and speed tracking rapidity of a permanent magnet linear synchronous motor (PMLSM), a novel control scheme combining the inverse system method and the internal model control is proposed in this paper. A decoupling pseudo-linear system can be obtained by cascading the inverse model of the PMLSM with the original system. In addition, in order to improve the robustness of the whole system and to reject the influence of the unmodeled dynamics and various disturbances to the linearizing control accuracy, the internal model controller is used as the extra closed-loop controller for the pseudo-linear system. …Therefore, the presented control scheme incorporates the advantages of both the inverse system method and the internal model control. The effectiveness of the proposed control scheme is verified by simulation and experimental results at various operations. Simulation studies are performed to prove the effectiveness of the proposed control scheme. Show more

Keywords: Permanent magnet linear synchronous motor (PMLSM), inverse system, linearizing control, internal model control

DOI: 10.3233/JAE-170040

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 523-534, 2017

Authors: Chen, Fan | Yang, Xiaolong | Gao, Shanghan | Chen, Yanhui

Article Type: Research Article

Abstract: In order to improve the pressure capacity of ferrofluid seal with large gap, ferrofluid sealing structure with two magnetic sources was designed. The magnetic field distributions in its sealing gap were analyzed by finite element method. The effects of sealing gap, ratio of permanent magnet length to its height, slot width and ratio of the pole piece height to the shaft radius on ferrofluid seal have been investigated. The results show that the pressure capacity of ferrofluid seal decreased significantly with the increase of the sealing gap. Its pressure capacity increases initially, then decreases and remains unchanged at last with …the increase of the ratio of permanent magnet length to its height. Its pressure capacity decreases firstly and then increases with the increase of the slot width. Its pressure capacity increases firstly and then decreases with the increase of the ratio of the pole piece height to the shaft radius. Show more

Keywords: Large gap, ferrofluid, seal, key parameters

DOI: 10.3233/JAE-170048

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 535-543, 2017

Authors: Bowen, L. | Vinolas, J. | Olazagoitia, J.L.

Article Type: Research Article

Abstract: The energy balance of internal combustion engines used in vehicles today shows that between 50 and 80% of the fuel energy is lost. This waste of energy has fostered a growing interest in energy harvesting systems in the automobile sector. This energy can be recovered, for example, from the cooling and exhaust systems, the brakes or the suspension system. With regard to suspension system harvesters, usually called Energy Harvesting Shock Absorbers (EHSAs), many solutions, based on different technologies, have been proposed so far in the literature available. Unfortunately, to date there is no commonly-accepted approach that allows the designers to …select the best technology to replace a conventional damper with another component, i.e. an EHSA, which harvests energy but at the same time offers the same contribution to comfort and handling as the conventional damper. This paper presents a general methodology which can be used to compare present or future EHSA solutions. It studies the technology behind direct drive and electromechanical shock absorbers, and an electromechanical representation is proposed for each of them. Besides, for comparison purposes, a common equivalent mechanical representation for each EHSA is suggested. Some experimental results, using track-recorded data to estimate an urban road profile and also the ISO 8608 standard class C roughness index, are included, which demonstrate the ability of the methodology to compare effectively different EHSAs which harvest energy but at the same time have the damping characteristics of a conventional shock absorber. Show more

Keywords: Energy harvesting, regenerative shock absorber, suspension, damper, shock absorber, vehicle, EHSA

DOI: 10.3233/JAE-170057

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 545-564, 2017

Authors: Li, Tonglin | Chen, Hanbo | Wang, Heng | Xiong, Bing

Article Type: Research Article

Abstract: In recent years, the controlled-sources electromagnetic method has been widely applied for oil and metallic ore exploration. It is necessary to study the effects of the constituents and microstructure in pyrite-bearing hydrocarbon-bearing reservoir sandstones on 3D marine controlled source electromagnetic sounding, so as to improve the accuracy of the marine controlled sources electromagnetic (MCSEM) Method. In this paper, we present a new finite element algorithm for 3D MCSEM modeling, which is based on unstructured grids. In the modeling, we adopted the secondary formulation for the quasi-static variant of Maxwell’s equation, so that the source singularity could be avoided effectively. We …first applied the four-phase incremental model to calculate the conductivity of the pyrite-bearing hydrocarbon. This is of use in studying the electrical conductivity of pyrite-bearing sandstones. The finite element equations were solved by means of the preconditioned IDR(s) method. We applied our algorithm to calculate the response of various key parameters of MCSEM (i.e. pyrite content, porosity, pyrite conductivity, grain aspect ratio and water saturation). The results of the modeling show the performance of the algorithm, and are expected to assist in future CSEM data interpretation when a pyrite-bearing sandstone reservoir is encountered. Show more

Keywords: Secondary formulation, IDR(s), marine controlled sources electromagnetic, multi-phase incremental model, unstructured mesh, vector finite element method

DOI: 10.3233/JAE-170073

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 565-581, 2017

Authors: Bao, Xiaohua | Fang, Jinlong | Ni, Youyuan | Xu, Wei | Wu, Changjiang

Article Type: Research Article

Abstract: Induction machines with conventional skewed rotor have lower starting torque compared with non-skewed rotor induction motors. In order to improve the electromagnetic torque, an induction motor with two different doubly skewed rotors was proposed in this paper. The fundamental electromagnetic torque and harmonic electromagnetic torque are analyzed by the virtual displacement method. Theoretical analysis shows that both doubly skewed rotor induction motor without middle ring (DSRIMWOMR) and doubly skewed rotor induction motor with middle ring (DSRIMWMR) can efficiently reduce the harmonic torque. The reduction of harmonic torque can improve the starting torque and reduce the torque ripple. The validity of …the analytical method was verified by a large number of three dimensional (3-D) finite element simulations. Results of 3-D finite element analysis (FEA) indicated that both DSRIMWOMR and DSRIMWMR can improve starting torque compared with the conventional skewed rotor induction motor. Furthermore, the optimal skew width for improving the starting torque and reducing torque ripple was ascertained according to different 3-D finite element simulations. Show more

Keywords: Starting torque, torque ripple, doubly skewed rotor induction motor, skew width, 3-D finite element method

DOI: 10.3233/JAE-170085

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 583-595, 2017

Authors: Vértesy, G. | Bálint, B. | Bingler, A. | Gyimóthy, S. | Bilicz, S. | Pávó, J.

Article Type: Research Article

Abstract: The magnetic flux density in the magnetizing coil during the hysteresis measurement was calculated. The influence of a slot, machined in a ferromagnetic plate was simulated. The size of the magnetizing yoke was changed and the influence of this modification was studied on the detectable flux density. The size of the slot and the thickness of the air gap, which appears between the magnetizing yoke and plate’s surface, was also taken into account. It was found that by this simulation the experimental conditions could be successfully modelled. A sensitivity analysis of the studied nondestructive testing setup was also performed and …the impact of different experimental parameters was analyzed. The results of simulation can be used successfully for determining the optimal parameters of the actual measurement arrangement if method Magnetic Adaptive Testing measuring technique (which is based on systematic measurement and evaluation of minor magnetic hysteresis loops) is applied. Show more

Keywords: Electromagnetic nondestructive testing, magnetic hysteresis measurements, magnetic adaptive testing, magnetic field simulation, sobol-indices

DOI: 10.3233/JAE-170089

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 597-612, 2017

Authors: Pan, J.F. | Li, Qianlong | Qiu, Li | Cheung, Norbert | Wu, Xiaoyu | Zhang, Bo

Article Type: Research Article

Abstract: A fuzzy position controller is employed for the linear switched reluctance motor. Performance comparison between the fuzzy controller and a proportional-differential (PD) controller is carried out. Under the PD controller, the absolute steady-state error is 44.5 ∼ 211.5 μ m under normal condition and 1157–1212 μ m under sustained time-variant disturbance circumstance, respectively. The absolute steady-state error of 3 μ m and 9 μ m can be achieved under the fuzzy controller in the normal and sustained disturbed circumstance. Experimental results demonstrate that the position tracking performance from the …proposed algorithm is superior to the conventional PD control strategy, both in normal circumstance and disturbance environment. Show more

Keywords: Position control, fuzzy controller, PD controller, linear switched reluctance motor, disturbance

DOI: 10.3233/JAE-170092

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 613-624, 2017

Authors: Lim, Dong-Kuk | Jung, Sang-Yong | Jung, Hyun-Kyo | Ro, Jong-Suk

Article Type: Research Article

Abstract: The cogging torque calculation of interior permanent magnet synchronous motors (IPMSMs) has only been conducted by the finite element method (FEM) due to their complexities. However, FEM analysis requires considerable computational time during the design process. To deal with this problem, a new analytical method is proposed to calculate the cogging torque in IPMSMs. The radial and circumferential air-gap flux density for calculating the cogging torque utilizes the magnetic equivalent circuit model, conformal mapping method, and approximate equations of the magnet end. The validity of the proposed method was confirmed by comparing the results of the proposed method with those …of FEM. Show more

Keywords: Analytic method, conformal mapping, interior permanent magnet synchronous motor, magnetic equivalent circuit

DOI: 10.3233/JAE-9170094

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 625-635, 2017

Authors: Zhang, Weichen | Chen, Feng | Wang, Jiawei

Article Type: Research Article

Abstract: An electro-magneto-thermo-elastic coupled model is proposed for the transient simulation of large bearing disassembly based on the induction heating technique. The computational complexity of the coupled model is decreased with a proposed semi-analytical method for calculating the displacement of the cylindrical workpieces under the temperature load. Based on the proposed method, the multivariate analysis with respect to the source location, the operating frequency and the source power is carried out to realize the optimization with the objective of minimizing the energy consumption and the disassembly time. The efficiency and validity of the proposed model are verified by the numerical tests.

Keywords: Induction heating, multi-physics, eddy current

DOI: 10.3233/JAE-9170097

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 637-643, 2017

Authors: Bai, Xubin | Chen, Feng | Wang, Jiawei

Article Type: Research Article

Abstract: An Adaptive Cell Method (ACM) is proposed for high-precision simulation of eddy-current problems on the uniform coarse grid. The calculation error of the Cell Method (CM) is analyzed to draw the conclusion that the discretization of the constitutive equations is the main error source. The spirit of the ACM is to decrease the discretization error by using the constitutive matrix recovery technique without refining the grid. The accuracy and efficiency of the proposed approach are verified by the numerical tests.

Keywords: Cell Method, adaptive cell method, eddy currents, quasi-static magnetic field

DOI: 10.3233/JAE-9170098

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. 4, pp. 645-652, 2017