International Journal of Applied Electromagnetics and Mechanics - Volume 60, issue 2

Authors: Qiu, Li | Yu, Yijie | Li, Tao | Feng, Guang | Su, Pan | Chang, Peng | Deng, Changzheng | Xiong, Qi

Article Type: Research Article

Abstract: To improve the heating efficiency of the induction cooker system, this paper adopts the method of introducing an adiabatic layer between the pot bottom and the coil. By using COMSOL software, the electromagnetic - thermal coupling model of the induction cooker is established to analyze the effect of the adiabatic layer on the food temperature and coil temperature, and finally the heating efficiency is explored. The obtained simulation results show good agreements with the experimental results, and then the effectiveness of the proposed method is verified.

Keywords: Induction cooker, adiabatic layer, heating efficiency, electromagnetic - thermal coupling model

DOI: 10.3233/JAE-180072

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 145-154, 2019

Authors: Tian, Lisi | Cao, Xiaoguang | Lv, Lankun | Wang, Haokun | Yu, Qiang

Article Type: Research Article

Abstract: Compared with L-and LC-filter, the LCL-filter attracts more and more research interests for its excellent harmonic suppression ability. However, the resonance peak of the LCL-filter may introduce potentially unstable dynamics that need to be carefully damped. Considering the PWM discrete nature and practical implementation in discrete form, to analysis the overall system stability is complex especially when considering the controller and the LCL-filter active damping as a whole system. Moreover different sampling frequency and different delay time that are specific in discrete domain influence the system stability scenario, which increase the analysis complexity. Different from the low order filter, LCL-filter …offers two kinds of possible current feedback, which presents totally different impact on overall system stability. In this paper, the stability of the overall system in discrete domain with two kinds of possible current feedback is investigated in detail. Three typical sampling frequency: high sampling frequency, medium sampling frequency and low sampling frequency are considered. And three typical delay time of active damping control: 0, T s ∕2, T s are introduced into stability analysis process. Experimental results get from a 3 kW laboratory prototype based on the TMS320F2808 are provided to validate the theoretical analysis presented in this paper. Show more

Keywords: Stability analysis, active damping, delay time, discrete domain, LCL-filter

DOI: 10.3233/JAE-180066

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 155-172, 2019

Authors: Zhao, Jianhui | Yue, Pengfei | Grekhov, Leonid | Wei, Kebiao | Ma, Xiuzhen

Article Type: Research Article

Abstract: In our study, the B–H magnetization curves at temperatures between 16 and 150 ∘ C and frequencies between 50 Hz and 1000 Hz were measured to analyse the effect of temperature and frequency on the magnetization characteristics of electrical iron DT4C. By researching a high-speed solenoid valve (HSV) for a common rail injector, the temperature and frequency dependence of DT4C and their effects on the electromagnetic force and dynamic response of a HSV were obtained. The research results showed that an increase in temperature could decrease the magnetic flux density; however, the decrease was …not apparent. The effect of temperature on the relative permeability depended on the range of magnetic flux density B . The temperature dependence of DT4C was weak in the temperature range of 16--150 ∘ C . This stability of magnetic characteristic of DT4C ensures that the dynamic response of a HSV could be maintained well for a common rail injector. Magnetization frequencies had a significant influence on the magnetization of DT4C. An increase in the frequency would delay the transition to the saturation magnetic flux density Bs . The effect of frequency on the electromagnetic force became increasingly significant as the driving current increased. In a frequency range of 50–200 Hz, the opening response time of a HSV could be maintained well. When the frequency was higher than 200 Hz, the opening time increased significantly with the frequency raised from 200 Hz to 1000 Hz, furthermore, the HSV was out of control and closed ahead of time. Show more

Keywords: Dynamic response, magnetic B-H curve, high speed solenoid valve, common rail injector

DOI: 10.3233/JAE-180022

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 173-185, 2019

Authors: Takei, Amane | Mizuma, Takeihito | Akatsuka, Motoki | Yamada, Tomonori

Article Type: Research Article

Abstract: This paper describes a method for evaluating the performance of electrical insulators exposed to winter environments using a large-scale numerical electrostatic analysis. Generally speaking, it is acknowledged that the presence of saltwater or accreted saline ice will degrade the ability of insulators to prevent electrical conduction. In our study, we began by confirming the insulation efficiency of insulators by conducting 50% impulse flashover voltage tests. Next, in order to study the performance of our evaluation method, the insulators were modeled via a parallel electrostatic analysis based on the hierarchical domain decomposition method. The mechanism for the deterioration of the insulation …performance was clarified with the proposed method. Show more

Keywords: Electrostatic analysis, ice accreted insulators, insulation performance evaluation, adventure system

DOI: 10.3233/JAE-170168

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 187-207, 2019

Authors: Qian, Junbing | Bao, Liping | Ji, Chuankun | Wu, Jing

Article Type: Research Article

Abstract: A permanent magnet synchronous linear motor (PMSLM) is a linear drive mechanism that converts electric energy into mechanical energy. PMLSMs have been deployed widely in modern precision industrial manufacturing. In this study, an air-gap magnetic field model of a rectangular permanent magnet array in a PMSLM is developed based on the Biol-Savart theorem and the molecular circulation model. Furthermore, an analytical expression for the magnetic field distribution of the air-gap space is derived. Ansoft and experimental measurement are used to model the PMSLM and calculate the magnetic induction intensity and validate the analytical model. The relation between the air-gap magnetic field …of a PMSLM and the geometrical dimension of the permanent magnet is analyzed. Show more

Keywords: Permanent magnet synchronous linear motor, permanent magnet, magnetic field analysis, air gap, magnetic induction intensity

DOI: 10.3233/JAE-170162

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 209-221, 2019

Authors: Ma, Xiaoping | Su, Sanqing | Wang, Wei | Yang, Yiyi | Yi, Shuchun | Zhao, Xuran

Article Type: Research Article

Abstract: Torsion tests on 50 Mn steel wire were implemented and illustrated in this research to probe into the relationship between normal components of self-magnetic-flux-leakage (SMFL) signals H p (y ) and early damage of steel wire subjected to torsional stress. Besides, a modified model with due consideration of coercivity and permeability varying with equivalent stress at elastic-plastic stage was presented to simulate H p (y ) signals of steel wire under torsion accurately. Relevant numerical simulations of magneto-mechanical coupling were performed. The results show that using zero crossing point (ZCP) of H p (y ) signals to …identify defect location does not apply to steel wire under torsion. However, there is crest (or trough) showing on magnetic signal curve prior to fracture. By utilizing location of crest (or trough), damage could be positioned accurately and ultimate fracture point could be forecasted in advance as well. Furthermore, simulation results obtained from the modified model are consistent with test results. Not only can study results demonstrate that MMM technique could be used for determining early damage of steel wire under torsion, but also provide certain reference for quantitative analysis about the relationship between damage and H p (y ) signals. Show more

Keywords: Steel wire, torsion, magnetic memory method, damage location, magneto-mechanical coupling

DOI: 10.3233/JAE-180075

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 223-246, 2019

Authors: Zhang, Guangwei | Yamamoto, Akio

Article Type: Research Article

Abstract: This work proposes a self-sensing method for a synchronous electrostatic film motor. The method utilizes the relation between the driving voltages and currents of the motor. Through several signal conversions on the measured motor currents, the system distills the information of the slider position to realize displacement sensing. The resulting system can track the slider position both for synchronous and non-synchronous operations. The system assumes stepwise motions of the slider and fully exploits the characteristic current features of the motions. Two different signal conversion methods have been tested using numerically simulated motor currents and real motor currents. The two methods …differ in terms of accuracy and noise immunity. Considering that the currents of the electrostatic motor are relatively small, the method with high noise immunity and relatively low accuracy was found useful for practical applications. The position resolution achieved by the method was in the order of the electrode pitch, which is 200 μm in the prototype motor used in this work. Show more

Keywords: Electrostatic film motor, displacement estimation, sensorless

DOI: 10.3233/JAE-180068

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 247-261, 2019

Authors: Xu, Junqi | Chen, Chen | Sun, Yougang | Ji, Wen | Lin, Guobin

Article Type: Research Article

Abstract: When the maglev train is running on the guideway, the coupling effect between the vehicle and the guideway will inevitably cause vibration. Especially when the guideway is flexible, the vibration of the vehicle will cause slight deformation of the guideway, which may cause resonance. The irregularity of guideway geometry is the main source of excitation for vehicle random vibration. On the premise that the guideway irregularities cannot be eliminated objectively and thoroughly. In order to analyze its vertical random vibration, the vehicle adopts the two stage suspension model, the guideway adopts the Euler–Bernoulli simple supported beam model, and the random …irregularity of the guideway itself is used as the vibration source to control. At present, the power spectrum method based on random vibration theory is generally regarded as the most reasonable method, but the computational efficiency problem brought by this method has always been the bottleneck of random vibration analysis. Therefore, from the point of view of computational mechanics, the pseudo excitation method (PEM) is used to simplify the calculation of random vibration and to calculate random vibration. The coupled motion equations of the maglev vehicle under random excitation are obtained, and the computational efficiency is greatly improved. In addition, the vehicle suspension state is simulated at different operating speeds, and the effect of feedback control parameters on the stability of the magnetic levitation system is proved by numerical simulation. Finally, the influence of random excitation on vehicle guideway coupling vibration and the reliability of levitation control performance under random excitation are verified by experiments. Show more

Keywords: Maglev system, random irregularity, the pseudo excitation method, dynamic characteristics, coupled vibration

DOI: 10.3233/JAE-180051

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 263-280, 2019

Authors: Wang, Zhen | Liu, Chunting | Wei, Weizhong

Article Type: Research Article

Abstract: The use of magnetic separation based on nanoparticles has been an efficient approach in many research fields and different industries. It has shown multiple advantages including high separation efficiency and fast separation speed as well as low cost, comparing to conventional sedimentation or centrifugation methods. The basic contents and modelling principles such as one-way and two-way coupling methods involving magnetic separation have been introduced specifically and comprehensively, which can be used for better understanding the process and optimizing design of magnetic separators. Then typical industry applications of magnetic separation including kaolin beneficiation, water treatment, protein purification, cell separation, and drug …delivery have been summarized in detail. Show more

Keywords: Magnetic separation, magnetic nanoparticle, industry applications, modelling

DOI: 10.3233/JAE-180087

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 281-297, 2019

Authors: Lahyaoui, Otmane | Lanfranchi, Vincent | Buiron, Nicolas | Martin, Floran | Aydin, Ugur | Belahcen, Anouar

Article Type: Research Article

Abstract: Soft ferromagnetic materials constitute the main components of magnetic circuits in electromechanical devices. However, their magnetic and magnetostrictive properties are strongly affected by mechanical loading. This can lead to a decrease in the performance and the efficiency of these devices and to a potential increase of the emitted noise. Aware of the importance of these factors, this paper proposes to study the effect of the mechanical stress on the magnetic and magneto-elastic properties of non-oriented electrical steel sheets. The stress dependency of permeability and Villari effect has been studied. Measurements of the magnetostrictive strain under applied stress are presented and …the anisotropic behavior under stress is described. Moreover, the ΔE effect has been observed and analyzed. The novelty of this work is the extension of the measurements to many directions of cut with respect to the rolling direction under tensile and compressive stress, as well as the demonstration of the magnetic and magnetostrictive anisotropy under uniaxial stress. Show more

Keywords: Magnetostriction, magnetization, mechanical stress, magneto-elastic effect, non-oriented electrical steel, magnetic material, anisotropy

DOI: 10.3233/JAE-180106

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 2, pp. 299-312, 2019