International Journal of Applied Electromagnetics and Mechanics - Volume 71, issue S1

Authors: Liu, Zhengshuai | Li, Yong | Su, Bingjie | Ren, Shuting | Ren, Yanzhao | Chen, Zhenmao

Article Type: Research Article

Abstract: In this paper, the imaging and evaluation of defects hidden within the stratified conductor via pulse-modulation eddy current testing (PMEC) is intensively scrutinised through theoretical and experimental investigation. Following the proposition regarding the optimal excitation signal of PMEC, a fused signal feature integrating the harmonic and pulsed characteristics of PMEC signals is proposed in an effort to further enhance the testing sensitivity and signal-to-noise ratio (SNR). By comparing with the features of conventional PMEC and pulsed eddy current testing (PEC), the superiority of the fused feature is identified via theoretical simulations. This is subsequently supported by the corrosion imaging results …obtained from the experiments, further indicating the advantage of the fused feature over traditional features in terms of testing sensitivity and SNR. Show more

Keywords: Pulse-modulation eddy current testing, feature fusion, defect imaging and evaluation, testing sensitivity, signal-to-noise ratio

DOI: 10.3233/JAE-220163

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S283-S293, 2023

Authors: Ogawa, Kazuki | Miyazaki, Riku | Funada, Kohmei | Uchida, Yamato | Uchino, Daigo | Ikeda, Keigo | Endo, Ayato | Kato, Taro | Narita, Takayoshi | Kato, Hideaki

Article Type: Research Article

Abstract: Recently, demand for thin steel plates has increased. In the manufacturing of thin steel plates, surface quality deterioration due to contact between the rollers and steel plate involved is problematic. We are investigating magnetic levitation conveyance to propose a noncontact conveyance system using electromagnets. However, the magnetic levitation of thin steel plates is unstable because of the deflection in the range where the electromagnetic force is not affected. Therefore, to improve the levitation stability, we are investigating a bending magnetic levitation system in which a thin steel plate is bent during magnetic levitation but not deformed plastically. In this study, …a dynamic analysis using the finite difference method is performed to understand the behavior of a thin steel plate during magnetic levitation. In the dynamic analysis, vibration is evaluated based on the displacement standard deviation. The dynamic simulation visualizes the dynamic behavior of a levitated flexible steel plate. Show more

Keywords: Electromagnetic levitation, bending levitation control, flexible steel plate

DOI: 10.3233/JAE-220167

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S295-S303, 2023

Authors: Li, Yiying | Fei, Zhangjun | Huang, Yanlan | Yang, Shiyou

Article Type: Research Article

Abstract: A metamaterial (MM) generally works on a resonance mode, and its permeability will vary sharply around this resonance frequency. Consequently, the performance of a MM will be largely degraded if it is designed using a traditional optimization technique without considering these inevitable imperfections in fabrications. In this regard, the robustness of a solution must be included in the design optimization of a MM, exacerbating additional computational burdens to the already costly design procedure arising from the application of a high-fidelity model. Consequently, it is demanding to reduce the function calls for a high-fidelity model in the robust design of a …MM. In this point of view, an optimization methodology by combining the genetic algorithm (GA) and a local search surrogate model is proposed for efficiently robust optimizations of a MM unit. Show more

Keywords: Genetic algorithm, metamaterial, robust optimization, surrogate model

DOI: 10.3233/JAE-220168

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S305-S311, 2023

Authors: Rao, Shaowei | Yang, Shiyou | Zou, Guoping

Article Type: Research Article

Abstract: A methodology to diagnose transformer faults based on dissolved gas analysis (DGA) is proposed. Since a fault is more sensitive to the ratios of gas contents, a general ratio feature extraction framework is proposed to generate a feature subset as the input of the diagnosis model. The feature subset is evaluated by the improved case-based reasoning (CBR) and optimized by using a proposed new algorithm called the k -optimal algorithm (k -OA). The comparison results between the k -OA and the genetic algorithm (GA) show that the k -OA is more efficient in solving such a combinatorial optimization problem. The …obtained optimal feature subset is used to diagnose a public transformer fault dataset, and a 92.6% diagnosis accuracy is observed as compared to that of only 85.1% diagnosis accuracy by using the original features. Show more

Keywords: Case-based reasoning, combinatorial optimization, fault diagnosis, feature extraction, transformer

DOI: 10.3233/JAE-220169

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S313-S320, 2023

Authors: Takeuchi, Yuka | Hamasaki, Atom | Kawaguchi, Hideki | Matsuda, Mizushi

Article Type: Research Article

Abstract: Cellulose is a promising sustainable material due to its flexibility and high strength. The light scattering characteristics of anisotropic cellulose crystals from various angles with magnetic orientation were experimentally clarified in this study. The intensity of the light scattered from cellulose crystals is reduced by the application of a magnetic field. Therefore, it was suggested that switching the magnetic field would allow the light intensity to be controlled similarly to an attenuator.

Keywords: Magnetic orientation, light scattering, cellulose crystal, diamagnetic material

DOI: 10.3233/JAE-220172

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S321-S327, 2023

Authors: Bergqvist, Anders

Article Type: Research Article

Abstract: A magnetic vector hysteresis model is presented using play hysterons as building blocks. The main difference compared to earlier play based magnetic hysteresis models is that instead of forming a superposition of plays with different coercivities, this work uses a set of identical plays which are connected in a chain so that the output of one play acts as input to the next. Like models using a superposition, this yields far more complex minor loop behavior than a single play is capable of. Comparisons are made with measurements on a nonoriented electric steel for BH curves and alternating and rotational …losses, showing satisfactory agreement. The approach is found to have both advantages and disadvantages compared to models using superpositions of plays. The problem of determining model parameters becomes simpler and the model can be reversed so either magnetic field or magnetization may be used as known variable. On the other hand, there is no apparent connection to underlying physical processes. Show more

Keywords: Magnetic hysteresis, vector hysteresis, electrical steel

DOI: 10.3233/JAE-220173

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S329-S332, 2023

Authors: Kuroda, Jumpei | Majima, Yuhei | Ogawa, Kazuki | Ikeda, Keigo | Kato, Taro | Endo, Ayato | Narita, Takayoshi | Kato, Hideaki

Article Type: Research Article

Abstract: In recent years, further improvements in the performance of internal combustion engines to reduce environmental burden have been demanded. The combustion state of an engine is affected by the parameters of the dynamic valve system, such as the opening/closing timing and the lift of the intake and exhaust valves. Therefore, we investigate an electromagnetic valve-drive system in this study. Two models are created to improve the magnetic circuit and increase thrust. To investigate the thrust characteristics of these actuators, an electromagnetic field analysis is conducted using the finite element method. Meanwhile, to investigate the effect of the yoke material on …the thrust, an electromagnetic field analysis is performed based on materials with different saturation magnetic flux densities and magnetic permeabilities. Show more

Keywords: Linear motor, linear actuator, voice coil motor, electromagnetic valve drive system, EVDS, electromagnetic

DOI: 10.3233/JAE-220174

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S333-S341, 2023

Authors: Kayama, Shuta | Ichikawa, Yusuke | Nagayoshi, Tatsuya | Kawamura, Shintaro | Ogawa, Kazuki | Ikeda, Keigo | Endo, Ayato | Kato, Taro | Narita, Takayoshi | Kato, Hideaki

Article Type: Research Article

Abstract: In the production line of thin steel plates, contact conveyance by rollers causes deterioration in the surface quality of the plates. To solve this problem, our research group has been continuously investigating the optimal placement of permanent magnets in hybrid magnetic levitation systems. In this study, when a thin steel sheet was magnetically levitated, the effect of the horizontal electromagnet position on the gap between the steel sheet and the permanent magnet was investigated through a permanent magnet configuration optimized using a genetic algorithm.

Keywords: Electromagnetic levitation control, thin steel plate, permanent magnet, genetic algorithm

DOI: 10.3233/JAE-220175

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S343-S353, 2023

Authors: Liu, Mengqi | Zhang, Chi | Sun, Yanhua | Jiang, Xiaoyuan | He, Lingsong

Article Type: Research Article

Abstract: As promising non-destructive testing (NDT) method, magnetic flux leakage (MFL) testing has been widely applied for steel structure detection. However, magnetic flux leakage (MFL) signal collected by the sensors is weak, especially for the small diameter wire rope. The methods of using the traditional circular coil sensors, or increasing the number of magnets is ineffective in some situations. This study proposes a new method of highly sensitive long-strip-shape coil sensors with an analogue signal processing circuit used to detect wire rope in the timing belt of wind turbines. It is investigated by theory analysis, circuit simulation, and experiment conduction. The …circuit is used to amplify the weak signal and filter high-frequency noise to obtain a high signal-to-noise ratio (SNR). Experiments show that the resolution of the method can reach 3 broken wires of 0.1 mm wire diameter, and the method can not only obtain a high SNR signal but also have good repeatability. Meanwhile, this method will have great significance in practical applications and provide some solutions for other similar NDT projects. Show more

Keywords: Non-destructive testing (NDT), magnetic flux leakage (MFL), wire rope, coil sensors, analog signal processing circuit

DOI: 10.3233/JAE-220177

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S355-S361, 2023

Authors: Uchino, Daigo | Hira, Takamasa | Ogawa, Kazuki | Ikeda, Keigo | Kato, Taro | Endo, Ayato | Kato, Hideaki | Narita, Takayoshi

Article Type: Research Article

Abstract: An ultra-compact electric mobility vehicle cannot be equipped with power steering, and the physical burden is large. Therefore, we are continuously researching steering support for an ultra-compact electric mobility vehicle equipped with a steer-by-wire system (SBWS). The SBWS has not been widely diffused because the steering and front wheels are connected only to electric signals and do not have a high redundancy level. However, the advantage of an SBWS is that the steering reaction torque felt through the steering wheel can be controlled freely. We investigated an active steering wheel system (ASWS) that can control an appropriate steering feeling for …each driver by being equipped with SBWS and evaluating the steering burden of each driver. So far, research on the SBWS has been considered to improve operability by transmitting road information and feeding back vehicle motion, however few research on an SBWS considers the physical and mental burden on the driver. In this study, we conducted a fundamental analysis of the effect of the steering reaction torque on the steering burden, focusing on the operating direction of the steering wheel. Show more

Keywords: Active steering wheel system, ultra-compact electric mobility vehicle, steering muscle burden, surface electromyogram, inverse kinematics

DOI: 10.3233/JAE-220179

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S363-S371, 2023