International Journal of Applied Electromagnetics and Mechanics - Volume Pre-press, issue Pre-press

Authors: Li, Daiyan | Zhang, Yanli | Jing, Ying | Wang, Zhen | Xie, Dexin

Article Type: Research Article

Abstract: A large number of experimental observations show that under two-dimensional (2-D) rotational magnetization, there is a complicated relationship between the magnetostrictive strain and magnetic flux density. In this paper, the magnetostrictive characteristics in a non-oriented electrical steel sheet under 2-D magnetization are measured and modelled based on the experimental system developed by the laboratory. The in-plane magnetostrictive strain tensor under the 2-D magnetization is expressed as nonlinear superposition of dynamic magnetostrictive strain in the rolling direction (RD) and transverse direction (TD), respectively. The magnetostriction’s first derivative with respect to magnetization depicts the pinning effect and the interaction among magnetic domains …which result in the hysteresis behaviour. And based on the particle swarm optimization (PSO), the model parameters are identified. The validity of the proposed model is verified by comparing the calculation results with the experimental ones. Studies have shown that the magnetostrictive properties in an electrical steel sheet have strong hysteresis behaviour under the 2-D magnetization, and the model proposed here can well characterize these characteristics. Show more

Keywords: Electrical steel sheet, magnetostriction, mathematical model, 2-D magnetization

DOI: 10.3233/JAE-210228

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-9, 2022

Authors: Li, Yongjian | Li, Yating | Cheng, Zhiguang | Tian, Yakun

Article Type: Research Article

Abstract: HVDC (High Voltage Direct Current) transmission equipment generally works under AC–DC hybrid excitation (with both DC-bias components and harmonics), increasing the loss of magnetic components and even causing local overheating. In order to study the influence of AC–DC hybrid excitation on the performance of magnetic materials, the loss properties of electrical silicon steel under AC–DC hybrid excitation are measured and modelled. This paper improves the iron loss model based on the Bertotti loss model by introducing a new term caused by DC bias. In addition, the improved loss model is combined with the transient loss model, and the iron loss …calculation is performed based on the results of the TEAM P21 extended model. The comparison between the calculated and measured loss shows that the improved loss model is more accurate than the traditional one. Show more

Keywords: AC–DC hybrid excitation, Bertotti loss model, TEAM Problem 21 Family, iron loss

DOI: 10.3233/JAE-210238

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2022

Authors: Zhang, Tao | Liu, Xuechao | Zhang, Weirui | Liu, Ruigang | Xu, Canhua

Article Type: Research Article

Abstract: Magnetic induction tomography (MIT) has been proposed as a novel, non-invasive, and non-contact technique for diagnosing brain injuries. The design of the hardware system of MIT is a challenging research area. In this study, we constructed a 16-coil MIT simulation model with an actual cranio-cerebral anatomical structure in COMSOL. We analysed the factors which influence the MIT signal by constructing different types of haemorrhagic stroke models. In addition, the safety of MIT devices was evaluated in detail using the specific absorption rate. The results show that the phase noise of the hardware data acquisition system should be less than 0.001° …for the detection of a small peripheral haemorrhage with 5 mL. The result of the specific absorption rate shows that the security of MIT equipment should not be overlooked, and we need to establish a trade-off between signal intensity and device security. This study can provide data to support additional improvements in the performance of hardware systems in the future. Show more

Keywords: Head model, magnetic induction tomography, numerical simulation, three-dimensional modelling

DOI: 10.3233/JAE-210231

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2022

Authors: Gao, Pengfei | Wang, Wenlei | Wu, Jie | Zhang, Hengyi | Zhang, Jitao | Tao, Jiagui | Deng, Wei | Pan, Jeng-Shyang

Article Type: Research Article

Abstract: Wireless power transfer (WPT) technology has been widely used in industrial and household fields. This technology is of great significance in the field of motor drives. However, if the WPT technology is applied to the motor drive and control system, power and control signals need to be transmitted at the same time, which will cause the problem of mutual interference between signals of different frequencies, and will also increase the difficulty of frequency decomposition on the secondary side. To solve the above problems, a dual-frequency simultaneous wireless information and power transfer (SWIPT) system using a tapped coil structure scheme is …proposed and the design principle of the tapped coil is given. Based on this scheme, a multi-frequency pulse width modulation (MFPWM) method is used to generate two components of different frequencies by the same inverter, which are automatically decoupled by the tapped coil, and finally transmitted to drive and control the motor. A closed-loop control strategy is used to solve the problem of precise motor speed control when the driving voltage of the wireless motor fluctuates. In the experiment, the motor speed increased from 1965 rpm to 2265 rpm, and the DC voltage corresponding to the set reference speed increased from 1.26 V to 2.30 V. The experimental results show that the scheme can control the BLDC motor speed stably and accurately. Show more

Keywords: Brushless DC motor, simultaneous wireless information and power transfer (SWIPT), motor drive and control, tapped coil, multi-frequency

DOI: 10.3233/JAE-210110

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-21, 2022

Authors: Wang, Lei | Wang, Qunjing | Zhou, Rui | Zhang, Tao | Feng, Youliang

Article Type: Research Article

Abstract: Due to the large amount of finite element calculation resources, the calculation stability is low. In order to obtain accurate torque data conveniently, a new torque modeling method is proposed in this paper. By establishing the minimum torque model, the finite element software is used to obtain elementary torque map, and the torque within the whole rotor motion range is built by polynomial fitting, and then the position torque in the process of rotor motion under different currents is obtained by multiple linear interpolation method, and converted to the global coordinate system by projection. The multicoil torque is superimposed and …corrected by using the dynamic error coefficient to obtain the final synthetic torque. Finally, the effectiveness of the modeling method is verified by simulation and experiments. The results show that this method not only ensures the modeling accuracy, but also speeds up the calculation. Show more

Keywords: Reluctance spherical motor (RSM), linear interpolation, torque map, multicoil, dynamic error coefficient

DOI: 10.3233/JAE-220018

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-19, 2022

Authors: Yang, Panpan | Zhou, Gongbo | He, Zhenzhi | Tang, Chaoquan | Zhu, Zhencai

Article Type: Research Article

Abstract: To improve the braking force of the Linear Permanent Magnet Eddy Current Brakes (LPMECB) under a large Air Gap (AG) length, this paper presents a novel structure of the LPMECB, named H-type Linear Permanent Magnet Eddy Current Brake (H-type LPMECB). To begin with, the analytical model of the LPMECB is established by using the equivalent magnetic circuit method, and it is found that the AG reluctance is greater than that of the other parts of the LPMECB. Based on this, a novel H-type LPMECB is proposed in order to compensate the influence of the AG. The H-type LPMECB adds Iron …Foils (IFs) in the AG. These IFs are rectangular sheets made of pure iron. Furthermore, the finite element model of the H-type LPMECB is established to optimize the geometry parameter of the IFs, then the braking performance of the H-type LPMECB is measured. The simulations show that the optimal geometry parameter of the IFs of the H-type LPMECB is 0.25 ∗ L , and the braking performance of the H-type LPMECB is superior to that of the LPMECB, around three times. Finally, experiments were conducted, which validated the simulations. Show more

Keywords: Air gap, braking force, eddy current brake, novel structure

DOI: 10.3233/JAE-210029

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-16, 2022