International Journal of Applied Electromagnetics and Mechanics - Volume 64, issue 1-4

Authors: Jiang, Chao | Liu, Wencai | Song, Yun | Wu, Xinjun

Article Type: Research Article

Abstract: The EMAT (electromagnetic acoustic transducer) has been used to measure the thickness of the metallic plate in some industries recently. Comparing with the piezoelectric transducer, its low energy conversion efficiency due to the lift-off effect limits its further application. Based on the eddy current energy partition, the distances between the copper sheet and the coils are studied. In consideration of the influence of magnetic flux density, a principle about the energy conversion efficiency and the coils position is proposed. The optimal distances between the copper sheet and the coils under a certain lift-off are obtained through a series of simulation …and experiment. The results offer a method for the EMAT structure design. Show more

Keywords: EMAT, energy partition, conversion efficiency lift-off effects

DOI: 10.3233/JAE-209430

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1135-1143, 2020

Authors: Hosokawa, Hiroyuki | Hirata, Katsuhiro | Niguchi, Noboru

Article Type: Research Article

Abstract: We propose a non-contact electromagnetic impact-torque device (EMI device) using induced currents, and its characteristics have been verified using 3-D finite element method (FEM) analysis and carrying out measurements on a prototype. This paper describes a new EMI device with a regenerative circuit. A boosting chopper circuit is connected to the proposed EMI device, and the impact torque is controlled using the regenerated power.

Keywords: Electromagnetic impact-torque device, boosting circuit, finite element method

DOI: 10.3233/JAE-209431

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1145-1154, 2020

Authors: Han, Zhen | Shi, Liwei | Yan, Bing | Zhang, Wenchao

Article Type: Research Article

Abstract: The field winding of conventional multiphase doubly salient electro-magnetic generator is wound across multiple stator poles. There is a problem that the flux paths of the respective phases are not completely symmetrical. A novel E-core stator was proposed, the basic topology of the multi-phase E-core doubly salient electro-magnetic generator (E-core DSEG) with symmetrical phase magnetic circuits is derived by using the electrical formulas. This establishes a theoretical basis for the design of multiphase E-core DSEG. Based on the finite element simulation software, the static characteristics of multi-phase E-core DSEG were analyzed, including magnetic field distribution no-load electromotive force, flux linkage, …self-inductance of field winding, cogging torque and so on. Finally, a prototype of three phases 18/20-pole generator was made and tested. The rationality of theoretical analysis and generator topology was verified by simulation and experiment. Show more

Keywords: DSEG, short circuit, multiphase, electromagnetic characteristic, E-core stator

DOI: 10.3233/JAE-209432

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1155-1164, 2020

Authors: Ayub, Muhammad | Hussain, Asif | Sirewal, Ghulam Jawad | Kwon, Byung-il

Article Type: Research Article

Abstract: This manuscript proposes a wye-delta winding configuration for brushless operation of a wound field synchronous machine (BL-WFSM). In existing third harmonically excited BL-WFSM topologies, the additional third harmonic component of the stator magnetomotive force (MMF) was produced by an extra thyristor drive circuit or by utilizing an additional inverter. In the proposed single inverter topology, the stator winding is divided into two coil sets: the wye coil and delta coil. Triplen harmonic currents are produced owing to the delta coils set and start to circulate in the delta coils. This triplen harmonic circulating currents produce a triplen harmonic pulsating MMF …in the airgap. The additional triplen harmonic pulsating MMF induces voltage in the rotor harmonic winding. This induced voltage in the harmonic winding is used to excite the rotor field. A 2D finite element analysis is performed, and the simulation results confirmed the operation principle of the proposed brushless topology. Show more

Keywords: Brushless, delta coils, MMF, triplen harmonic, wye coils, WFSM

DOI: 10.3233/JAE-209433

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1165-1172, 2020

Authors: Kurishima, Yusuke | Hashimoto, Hirokazu | Okuyama, Takeshi | Tanaka, Mami

Article Type: Research Article

Abstract: In this paper, a measurement system of swallowing motion is developed. A piezoelectric film is used as sensitive material of the sensor to measure the body surface deformation due to swallowing. We focused on laryngeal prominence and digastric muscle which are active during swallowing and developed sensors to attach to skin above laryngeal prominence and digastric muscle. As a result of experiments, it was confirmed that output fluctuation occurred at the swallowing. Next, by comparing the frequency spectral density distribution of sensor outputs during swallowing and resting, it was found that the output waveform during swallowing is mainly composed of …larger frequency components below 20 [Hz] than that during resting. From the results, it was suggested that the developed measurement system is available to detect the swallowing from skin deformation without obstructing the motion. Show more

Keywords: Swallowing, piezoelectric sensor, PVDF film

DOI: 10.3233/JAE-209434

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1173-1182, 2020

Authors: Wang, Minghui | Yu, Hongliu

Article Type: Research Article

Abstract: Fecal incontinence caused by sphincter dysfunction is an unresolved problem which has a serious effect on patients, both physically and psychologically. For patients with severe symptoms, treatment with an artificial anal sphincter could be a potential option to restore continence. Acticon Neosphincter still has safety and efficacy problems, which is the only device certified by the US Food and Drug Administration. The biomechanical compatibility is the key problem of artificial anal sphincter in the clinical application. This paper describes an artificial anal sphincter with superelastic shape memory alloys and its mechanical properties assessment in artificial intestine models. The new design …was developed as a low invasive and constant force or pressure prosthesis with a simple structure to solve the problem of severe fecal incontinence in patients. Show more

Keywords: Fecal incontinence, artificial anal sphincter, constant force, shape memory alloys, superelastic

DOI: 10.3233/JAE-209435

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1183-1190, 2020

Authors: Narita, Takayoshi | Oda, Yoshiho | Ito, Yasuaki | Kato, Hideaki

Article Type: Research Article

Abstract: The grasping and conveying of an object by utilizing the frictional force generated by contact are performed during various steps in the process of manufacturing industrial products. Deterioration of the surface quality due to these contacts is a problem. A noncontact way to transport steel plates using electromagnetic force has been proposed as a solution to these problems. In such applications to date, electromagnets are installed in the vertical direction. However, if the steel plate is thin and lacks sufficient flexural rigidity, it is difficult to exert enough suspension force to levitate the entire steel plate. To solve this problem, …we propose an edge-supported electromagnetic levitation system suitable for flexible steel plates using electromagnets installed in the horizontal direction. In this paper, we report on levitation experiments to verify the effectiveness of the proposed system and discuss characteristics of the horizontal positioning of electromagnets and levitation suspension. Show more

Keywords: Electromagnetic levitation, metal foil, noncontact support

DOI: 10.3233/JAE-209436

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1191-1198, 2020

Authors: Wang, Xiang | Wang, Xiaoyu | Chai, Hongyou | Gao, Feng | Wang, Haowei | Ji, Hongli | Qiu, Jinhao

Article Type: Research Article

Abstract: In order to suppress the vibration of large-scale flexible structures which are applied on the spacecraft, a semi-active control method based on fuzzy adaptive SSDV (synchronized switch damping on voltage) technique is proposed. The value of voltage source at the switching moment is adjusted adaptively by using fuzzy logic, in order to improve the stability and control precision of the semi-active control system. The feasibility of this method is verified by two kinds of experiments with typical disturbance conditions. By comparing different adaptive displacement-voltage curves, the fuzzy adaptive method can achieve higher control precision. For the initial displacement disturbance of …10 mm, the fuzzy adaptive SSDV method can increase the system damping ratio from 0.6% to 5.1%. The control effect decreases with the increase of initial displacement. For the disturbance caused by the mechanism at the tip position, the method can effectively shorten the vibration damping time and reduce the displacement from 0.3 mm to 0.04 mm. Show more

Keywords: Large-scale flexible structure, semi-active control, synchronized switch damping technique, fuzzy logic

DOI: 10.3233/JAE-209437

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1199-1206, 2020

Authors: Cheng, Jun | Yu, Cheng | Xu, Shuai | Qiu, Jinhao | Takagi, Toshiyuki | Xu, Dezhang

Article Type: Research Article

Abstract: In carbon fiber reinforced plastic (CFRP) composite, the alignment of continuous carbon fibers guides the directional flow of eddy currents, which is beneficial to the structural and damage detection. In this study, for the purpose of impact damage repair, the transmitter-receiver (T-R) and the flat-tangent eddy current probes are used to determine the fiber orientations and stacking sequence in the CFRP laminate by surface scanning. Theoretical analysis shows that the T-R probe can flexibly pick up the magnetic field generated by the stretched eddy current in CFRP layers. In the meanwhile, the flat-tangent probe possesses layer selective characteristics. By calculating …the fiber distribution images of individual directions based on two-dimensional fast Fourier transform (2D-FFT) and comparing the order of pixel intensity values of these images, the fiber orientation and the stacking sequence in the laminate plates can be obtained simultaneously, which provides guidance for damage detection and repair of the CFRP structures. Show more

Keywords: Eddy current testing, carbon fiber reinforced plastic, directionality measurement, image processing, two-dimensional fast Fourier transform

DOI: 10.3233/JAE-209438

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1207-1215, 2020

Authors: Li, Dawei | Li, Guijuan | Sun, Lin | Chen, Yunfei

Article Type: Research Article

Abstract: The effects of smart-material-based active surface perturbation (i.e. piezo-ceramic actuators) on wall shear stress and noise metric have been investigated by simulations and wind tunnel experiments. A periodic vibration through the application of piezo-ceramic actuators is imposed on the surface of a plate, and the vibration position is located on the upper part of the leading edge of the plate. Both the control results from simulations and experiments are close to each other, when the control parameters are the same. The simulations and wind tunnel experiments show that downstream skin-friction drag and noise metric can be reduced with the active control, …and the reductions strongly depend on control parameters. Comparing with the near wall flow structures, the turbulent kinetic energy and characteristic turbulence length scale in the turbulent boundary layer can be controlled with the piezo-ceramic actuator. Show more

Keywords: TBL, piezo-ceramic actuators, third keyword

DOI: 10.3233/JAE-209439

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. 1-4, pp. 1217-1226, 2020