International Journal of Applied Electromagnetics and Mechanics - Volume 50, issue 2

Authors: Ghandehari, Mehdi Bahdorzadeh | Khazaei, AliAkbar | Vaezi, Sedigheh

Article Type: Research Article

Abstract: An efficient and practical method to suppress the resonant frequency of a rectangular enclosure with aperture has been proposed. In this paper a lossy dielectric has been used as a matched load termination which acts as a wave absorber at the end of the shielding box. Transmission line method was used for modeling the rectangular enclosure with aperture under electromagnetic interference wave and the results were verified by transmission line matrix method and CST software. Also a complete range of measurements were performed to find the susceptibility of the shielding box against electromagnetic interferences. The proposed method resulted in …a very good improvement of the shielding effectiveness of the enclosure at the resonant frequency and the results were verified by measurement. Show more

Keywords: Rectangular shielding enclosure, shielding effectiveness (SE), absorber, lossy dielectric termination, electromagnetic interference

DOI: 10.3233/JAE-140181

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 215-224, 2016

Authors: Peng, Chia-Mei | Chen, I-Fong | Hung, Ching-Chih | Hao, Zheng

Article Type: Research Article

Abstract: A novel dual cross-shaped shorted-slots loaded patch antenna is proposed and analyzed in this article. The radiated patch antenna was chiseled two cross-slots, there are shorted-lines to be set at the middle- and cross-points of slots, which is designed to be operated at dual-ISM (Industrial, Scientific, and Medical) band (2.4 and 5.8 GHz bands). A prototype of the proposed antenna with 63 mm in length, 7.6 mm in height and 72 mm in width is fabricated and experimentally investigated. The experimental results indicate that the VSWR ≤ 2.5 bandwidths achieved were 13.3% and 15.9% at 2.45 GHz and …5.5 GHz, respectively. There is good agreement between the simulated and measured results. Show more

Keywords: Patch antenna, cross-shaped shorted-slots loaded, dual-band, ISM band, cross-slots

DOI: 10.3233/JAE-140185

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 225-232, 2016

Authors: Bao, Xiaohua | Wang, Hanfeng | Di, Chong | Cheng, Zhiheng

Article Type: Research Article

Abstract: Large submersible motors make a huge contribution to national security prevention and control of water. But the eccentricity fault has a strong impact on the operational reliability. Therefore, this paper uses new diagnostic signals of air-gap magnetic field to detect eccentricity fault in submersible motor. Compared with the previous papers, this paper combines the effects of eccentricity and slotting. Firstly, a new air-gap permeance model is established considering slotting effect aimed at eccentric motor. Then the time harmonics of air-gap magnetic field are obtained based on MMF and permeance wave approach. Compared with healthy motor, the characteristic frequencies are chosen …as diagnostic signals. The air-gap magnetic field is measured by search coil placed around stator tooth. The way is applied to detecting dynamic eccentricity and mixed eccentricity. Finally, for validating the theoretical results, the induced voltages of search coil are gained under different conditions in high voltage submersible motor by finite element method. The simulation is consistent with the theory in the process of data analysis. Show more

Keywords: Submersible motors, eccentricity fault, diagnostic signal, slotting effect

DOI: 10.3233/JAE-150004

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 233-245, 2016

Authors: Yan, Wei | Yu, Jing | Tang, Qiang | Zhang, Hailong | Cao, Jincheng | Wang, Enrong

Article Type: Research Article

Abstract: The controllable magneto-rheological damper has been widely used in vibration mitigation system, such as vehicle suspension and aerospace landing gear, which is subjected to the direct magnetic field based on the magneto-rheological damper controller under semi-active control strategy. Due to the displacement vibration and semi-active control strategy, conducted electromagnetic noises are generated through the power supply. In the paper, the conducted electromagnetic interference noise mechanism and model are proposed for the magneto-rheological damper with semi-active control strategy based on the theoretical and simulation analysis. Then, a novel smoothing algorithm is designed to reduce the above conducted electromagnetic interference noises. The …simulation and experiment results show that conducted electromagnetic interference noises can be suppressed 2-8 dBμ V by employing the present smoothing algorithm and comply with EN 55022, thus it can support the development, application and safety & electromagnetic compatibility design for the MRD device. Show more

Keywords: Magneto-rheological damper, electromagnetic interference, conducted EMI noise, semi-active control strategy, noise mitigation

DOI: 10.3233/JAE-150006

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 247-254, 2016

Authors: Uddin, M. Jasim | Ullah, M. Habib

Article Type: Research Article

Abstract: A comparison of balanced and unbalanced backward wave %direction dispersion relations and the constitutive electromagnetic effective parameters of dielectric constant, %as well as magnetic permeability are obtained. In the balanced case, the initial transmission line lies in left handed (LH) medium and the next %steps of to cut-off frequency of higher order regions transmission line becomes in right-handed (RH) medium. In the unbalanced case, there are a tiny reject band displays due to the attenuations. It is also desirable for %left handed metamaterial parameters extraction properties should behave in antiresonance behaviour in the band gap regions. The proposed extraction technique …shows the suitable results for dual negative magnetic permeability and electric permittivity that match with the theory. To demonstrate the infinite wave investigations, there are four unit cell of complementary split-ring resonators (CSRRs) microstrip implementation is obtained and the equivalent lumped element circuit is analyzed. The theory and experiment result exhibits excellent agreement that ensures minimum loss and electrical small size due to less than wavelength dimensions. Show more

Keywords: Metamaterials, dielectric constant, permeability, dispersion diagram

DOI: 10.3233/JAE-150009

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 255-262, 2016

Authors: Wang, Wen-Juan | Ren, Xiang | Sun, Yang | Li, Hao | Liu, Ma-Bao

Article Type: Research Article

Abstract: Detecting structural strain has become a momentous part of Structural Health Monitoring (SHM), however, conventional strain sensing technologies cannot meet the requirements of long-time, low-cost, real-time, etc. In order to surmount these shortcomings, rectangular microstrip patch antennas were designed, manufactured and utilized as strain sensors to detect the structural strains, and the detailed experimental setup was presented as well. A linear relationship with the coefficient of -1 between the percentage of resonant frequency shift of the microstrip patch antenna and the structural strain was theoretically derived and validated by the HFSSTM simulation as well as the experimental results.

Keywords: Microstrip patch antenna, structural health monitoring, resonant frequency, strain measurement

DOI: 10.3233/JAE-150014

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 263-273, 2016

Authors: Liao, Y.-H. | Zhu, H.-C. | Huang, K.-M.

Article Type: Research Article

Abstract: In this paper we present a fast time-domain algorithm to study the electromagnetic pulse heating on dispersive medium. Using the proposed fast algorithm, the long heating process can be compressed by accelerating thermal conduction and scaling the power dissipation density. Comparing with the previous computation of several pulse periods, the proposed algorithm can deal with the heating process up to billions of pulse periods. Besides, employing the proposed algorithm, we study a 2D water post heated by electromagnetic pulses. The results reveal that comparing with continuous microwave heating, pulse heating cannot improve temperature uniformity or enhance heating efficiency.

Keywords: Electromagnetic pulse heating, fast algorithm, temperature uniformity, heating efficiency, Debye medium

DOI: 10.3233/JAE-150038

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 275-282, 2016

Authors: Cai, Jinliang | Sun, Xiaoying | Zhao, Xiaohui

Article Type: Research Article

Abstract: A new global description of shielding effectiveness is proposed in consideration of total energy storage in a metal enclosure, in order to replace some existing descriptions defined on one specific point, such as frequency domain shielding effectiveness and time domain shielding effectiveness. Electric fields and magnetic fields are considered globally in this new description, and numerical evaluation according to this new description with different transient pulses can be obtained. Simulation performed on a rectangular cavity having a circular aperture excited by the pulses is provided to show the validity of our proposed description.

Keywords: Shielding effectiveness, total energy reduction, enclosure, transient pulses

DOI: 10.3233/JAE-150061

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 283-295, 2016

Authors: Yang, Yongming | Liu, Xingmou | Yang, Fan | Jadoon, Ammad | Zhang, Chenyang

Article Type: Research Article

Abstract: Monopole operation model of Ultra High Voltage Direct Current (UHVDC) system, DC bias has great influence on the safety and stability of the system, especially for transformers, including temperature rising and increased in vibration. However, there is less research have done on increased vibration of transformer due to influence of DC bias on HVDC system. This study explored transformer vibration caused by DC bias, including the principle of transformer DC magnetic bias and the related calculation method. The mathematical model of the electromagnetic force coupling of the transformer core was also studied and after that its core magnetic field and …force field were analyzed. The displacement change of the transformer core which included core clamps and fixed structures were analyzed and discussed. Results revealed that the leakage flux of the clamps increases with DC bias and odd harmonics appeared in each displacement component. Specifically, the direction of the y displacement component changed, and the maximum displacement occurred with the 90-degree phase shift. Then, vibration experiment was done to analyze the DC bias characteristic of core, which also valid the effectiveness of the built simulation mode. Results indicate that amplitude and harmonics of the core limb vibration increase greatly under DC bias condition. The research of paper will also serve as references for addressing the vibration problems of transformers under DC bias conditions. Show more

Keywords: DC bias, transformer, vibration, coupling field

DOI: 10.3233/JAE-150078

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 297-309, 2016

Authors: Samsuzzaman, M. | Islam, M.T. | Mandeep, J.S. | Mahmud, M.Z. | Alam, T. | Islam, M.M.

Article Type: Research Article

Abstract: A miniaturized multiband printed antenna designed for high dielectric ceramic filled Bio plastic composite material is presented. The multiband antenna formed by Y shaped patch with a partial ground plane. The performance benchmarks of the proposed antenna have been experimentally verified by fabricating a printed prototype. The experimental results confirm that the proposed antenna achieves -10 dB impedance bandwidth of 10.07% (1.79-1.98 GHz) at lower band and 8.83% (2.38-2.6 GHz) at the upper band, respectively. The antenna configuration and parametric study have been carried out with the help of the commercially available EM simulator and a good harmony is apparent …between experimental and numerical results. Moreover, the antenna has a simple planar structure of a small area of only 38 mm × 40 mm. The proposed antenna can operate PCS1900 and WLAN bands. Good radiation characteristics, gain and radiation efficiency are obtained over these operating bands. Show more

Keywords: Dual band, printed antenna, bio plastic material substrate

DOI: 10.3233/JAE-150087

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 50, no. 2, pp. 311-320, 2016