International Journal of Applied Electromagnetics and Mechanics - Volume 57, issue 3

Authors: Safdarzadeh, O. | Afjei, E. | Torkaman, H.

Article Type: Research Article

Abstract: Rotary-linear motors which produce linear and rotary motions simultaneously have coupled magnetic paths. In this paper, coupling of a Rotary-Linear Switched Reluctance Motor (RLSRM) is studied and formulated. Then, an algorithm based on inductance profiles of the motor phases is proposed to decouple the motions – rotary and linear movements. This algorithm is developed from two excitation modes which produce the linear force and rotary torque, independently. Therefore, the control on the rotary and linear motions is realized by controlling the torque and force, respectively. Finite Element Analysis (FEA) is applied to the RLSRM model and the obtained results are …utilized in the algorithm. A control flowchart is presented for applying the motion modes. The algorithm is implemented on a microcontroller and applied to a fabricated model. Experimental results are measured to verify effectiveness of the proposed control algorithm. Show more

Keywords: Magnetic decoupling method, finite element analysis, rotary-linear motor, SRM, hybrid motion

DOI: 10.3233/JAE-170044

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 257-274, 2018

Authors: Zhou, Yang | Bao, Xiaohua | Wang, Chunyu | Di, Chong

Article Type: Research Article

Abstract: Eccentricity problem is always ineluctable in rotating electric machine, especially in large electric machine. Hence, the influence of eccentricity in operating machine is necessary to be investigated. According to the investigation, current of different parallel branches are varied under the same eccentricity. This paper focuses on comparative current analysis on two types of parallel branches in consideration of static and dynamic eccentricities. Parallel branch model in circumferential position is established for analysis and explanation of branch current due to eccentricity. Stator winding current and rotor wingding current are worked out under static and dynamic eccentricity at two types of parallel …branches. Their winding losses are calculated for comparison, respectively. Finite element model simulations are used for validation. Show more

Keywords: Static and dynamic eccentricity, parallel branch, current analysis, winding loss

DOI: 10.3233/JAE-170124

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 275-293, 2018

Authors: He, Wen | Tang, Bo | Jia, Shushi

Article Type: Research Article

Abstract: A novel broadband electromagnetic angular vibrator with a disk-type rotating coil is brought forward to satisfy the calibration demand of various angular vibration transducers. First, the structure of the electromagnetic angular vibrator is introduced, and the electromechanical coupling equation is established to reveal the relation between the input and output of the vibrator. Then, in order to realize wide operating frequency range and low total harmonic distortion of angular motion output, four key technologies have been adopted in our angular vibrator, which include a rotating coil made of a multilayer printed circuit board, a rotating component with a high torsional …resonant frequency, a double-magnetic-source magnetic circuit with pole shoes and a linear suspension device with large angular displacement. Finally, the performance indexes and the total harmonic distortion of output motion waveform from the developed broadband electromagnetic angular vibrator are measured. The test results show that the angular vibrator can output maximum angular displacement of 60 ∘ and maximum angular acceleration of 2000 rad⋅ s - 2 , and the total harmonic distortion of the angular acceleration waveform from the developed vibrator is less than 1% over its whole operating frequency range from 0.01 to 1200 Hz, which has met the requirement of the angular vibrator for calibration according to ISO 16063-15: 2006. Show more

Keywords: Electromagnetic, angular vibrator, rotating coil, magnetic circuit, linear suspension device

DOI: 10.3233/JAE-170132

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 295-307, 2018

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

Article Type: Research Article

Abstract: High-altitude electromagnetic pulse may cause damage to electronic equipments through coupling pipeline system. In order to study the effects of high-altitude electromagnetic pulse on overhead pipeline, the electromagnetic field-to-overhead pipeline coupling equations are derived from Maxwell’s equations. The coupling equations are solved in frequency domain by applying the Green’s functions, and the time-domain waveforms of induced currents and voltages are obtained by using inverse Fourier transform. The currents and voltages at both ends and in the middle of pipeline are calculated by MATLAB software. It is shown that the peak values of the currents along the pipeline don’t vary much. …The voltages at the 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. The effects of system characteristics on induced voltages are presented, such as the length of the pipeline, the height 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, overhead pipeline, coupling equation, induced current, induced voltage, system characteristics

DOI: 10.3233/JAE-170137

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 309-324, 2018

Authors: Liu, Yafeng | Wang, Xinjie | Qiao, Kun | Wang, Jiong

Article Type: Research Article

Abstract: The lanthanum-doped lead zirconate titannate (PLZT) ceramic has been widely used in light-controlled wireless actuators activated by ultraviolet light for their characteristic of converting light energy directly into the mechanical energy. The photovoltaic effect of PLZT is the result of multi-physics fields coupling, and the primary purpose of this article is to provide a comprehensive experimental analysis on the influence of photo-induced deformation of PLZT ceramics under the action of bias electric field. To this end, the amount and the speed of arriving at the electrodes of photo-generated carriers are analyzed. Furthermore, whether the bias electric field promotes the photovoltaic …effect is investigated by a series of experiments. The experimental results indicate that the deformation of PLZT ceramic with combined action of ultraviolet light and bias electric field is larger than that with only irradiation action. However, the increment is only contributed by bias electric field based on the converse piezoelectric effect, and the bias electric field has no effect on the photo-generated carriers. Therefore, adding a bias electric field cannot promote the photo-induced deformation of PLZT. Show more

Keywords: PLZT ceramic, bias electric field, photo-generated carriers

DOI: 10.3233/JAE-170152

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 325-335, 2018

Authors: Qiu, Li | Yu, Yijie | Wang, Ziwei | Yang, Yuqi | Yang, Yaqin | Su, Pan

Article Type: Research Article

Abstract: As a high-speed forming technology, electromagnetic forming has been more and more widely used because it can improve the material forming performance greatly. In electromagnetic forming process, the pulsed electromagnetic force generated by the coils is the load of the workpiece, hence its distribution characteristics have a great influence on the workpiece forming performance. Based on the basic principle of electromagnetic forming, this paper introduces and analyzes some latest electromagnetic forming technologies with different coil systems, including electromagnetic incremental forming, space-time-controlled multi-stage pulsed magnetic field forming, and electromagnetic tube expansion with axial compression. Aim at each forming method, the following …contents are mainly studied: 1) The key technical problems solved by this method. 2) The structure of the coil system. 3) The distribution of magnetic flux density and electromagnetic force. 4) The advantages and disadvantages of the method. Through above analysis, it is hoped that the basic idea of technological innovation in electromagnetic forming is clarified in this paper, which can provide guidance for the future innovation direction of electromagnetic forming. Show more

Keywords: Electromagnetic forming, coil system, axial electromagnetic force, radial electromagnetic force

DOI: 10.3233/JAE-170163

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 337-345, 2018

Authors: Li, Zhao | Wang, Dazhi | Zheng, Di

Article Type: Research Article

Abstract: Accurate analytical model is critical for the design and optimization of the electromagnetic devices. In this paper, a fully 3D analytical model for eddy-current couplers with a Quasi-Halbach magnet array is presented. The originality of this paper lies in the Halbach magnet array with arbitrary magnetization direction and the eddy currents generated in conductor rotor are considered in the 3D analytical computation. To avoid the complex computation with Bessel function, the 3D cylindrical geometry is linearized and discussed in 3D Cartesian coordinates. The magnetic scalar potential in the non-conductor region (PM, air-gap, and back iron) and magnetic field strength in eddy-current …region (conductor disk and its back iron) are calculated based on the separation variable method. The electromagnetic field, axial force and torque are obtained. In the end, by using the 3D finite element analysis, the feasibility and validity of the general 3D analytical model are verified. Show more

Keywords: Analytical model, eddy-current couplers, Halbach array

DOI: 10.3233/JAE-170164

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 347-366, 2018

Authors: Xiong, Qi | Huang, Hao | Deng, Changzheng | Li, Liang | Qiu, Li | Tang, Hongtao

Article Type: Research Article

Abstract: Low forming accuracy is the main defects in electromagnetic forming process of sheet metal. One of the main reasons is that shapes of the coil and required workpiece are cylindrical and deep concave respectively. The distance between the coil and the side wall of deformed sheet metal is too far in forming process, which leads to a consequence that electromagnetic force in the side wall is not enough. To solve this problem, a solenoid field shaper was introduced to enhance the electromagnetic force at the side wall, and then improve forming accuracy of electromagnetic forming of sheet metal. To verify …the effectiveness of the method, a series of simulations based on circuit-electromagnetic-structure were finished. The results showed that the maximum electromagnetic force with field shaper increased more than 10 times at the side wall. And the maximum deformation was 1.18 mm which can improve forming accuracy effectively. The presented method and results can be helpful in designing electromagnetic forming systems of sheet metal. Show more

Keywords: Electromagnetic forming, sheet metal, forming accuracy, field shaper

DOI: 10.3233/JAE-180001

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 57, no. 3, pp. 367-375, 2018