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

Authors: Hasan, Alfaisal A. | Mekheimer, Khaled S. | Tantawy, Bassem E.

Article Type: Research Article

Abstract: The present work studies magnetohydrodynamic stability with streaming resistive triple superposed fluid layers. This system is influenced by an oblique magnetic field. The solution of motion equations by using the method of perturbation analysis under the boundary conditions which leads to deriving the dispersion relationship describing the behaviour of the perturbed and unperturbed system. The effect of different parameters on the stability and the instability of this system was studied. Regions of stability and instability are identified by drawning the curves to illustrate the regions of stability and instability behaviour. It is found that the magnetic field permeability coefficient, the …intensity of the magnetic field values, the increase of the fluids density values and the streaming velocity have destabilizing influences on the considered system. The presence of an oblique magnetic field plays a stabilizing role and can be used to retard the destabilizing influence. Show more

Keywords: Self-gravitating, resistive, superposed fluids, streaming, oblique magnetic fields

DOI: 10.3233/JAE-190110

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-11, 2020

Authors: Li, Peng | Jiang, Jiafu | Liu, Sheng | Fu, Peng | Huang, Yiyun | Hui, Xie | Qiang, Liu | Hongyan, Zuo

Article Type: Research Article

Abstract: As an important electrical power distribution system of ITER (International Thermonuclear Experimental Reactor) device, PPEN (Pulsed Power Electrical Network) feeds the pulsed loads for the superconducting coils and the heating and current driving systems. The PPEN transforms 400 kV power grid to 66 kV and 22 kV distribution voltage levels by 3 main step-down transformers. In this paper, the power loss of PPEN transformer is analyzed and calculated. The 2D PPEN transformer model is built. The temperature rise of PPEN transformer is calculated by ANSYS software. To validate the feasibility and correctness of the proposed method, the temperature rise test of PPEN transformer …is carried out, then the related results are compared with the test data. Show more

Keywords: ITER, PPEN, temperature rise, ANSYS, short-circuit method

DOI: 10.3233/JAE-190105

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2019

Authors: Bai, Peigen | Shi, Pengpeng | Zhao, Yingsong | Chen, Hong-En | Xie, Shejuan | Chen, Zhenmao

Article Type: Research Article

Abstract: As one typical material of nuclear power plant structure, austenitic stainless steel (SS) is often accompanied by residual stress and plastic deformation during their manufacture and application, which may affect the structure service safety. In this paper, the effects of the composite state of residual stress and plastic deformation on the pulsed eddy current testing (PECT) signals of SS are studied theoretically and experimentally. By considering the electromagnetic properties in the composite state, the PECT theory is established for the 304 SS in the composite state. The numerical simulation is completed using the reduced vector potential method and the verification …experiment is also carried out. The comparison between simulation and experimental results shows that the peak value of the PECT signal increases with the increase of plastic deformation or residual stress. This means that if the residual stress is not considered in the composite state, the effectiveness of the PECT method for evaluating plastic deformation may be seriously affected. Show more

Keywords: 304 austenitic stainless steel, composite state, plastic deformation, residual stress, pulsed eddy current testing

DOI: 10.3233/JAE-190124

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-12, 2019

Authors: Chang, Jiujian | Fan, Yanen | Zhu, Bo | Luo, Liang | Wu, Jinglai | Pan, Yishan | Kang, Peng

Article Type: Research Article

Abstract: This paper takes the demand of high power density motor for new energy vehicles as the application background. In order to solve the problem of low power density of radial flux motor, a novel direct cooling yokeless and segmented armature axial flux machine (YASA) is proposed. The thermal-fluid multi-physical coupling field of YASA motor has been studied by combining numerical analysis and computational fluid dynamics (CFD). On this basis, the internal relationship among the output power, flow resistance and structural parameters of the cooling system has been studied, and then the parameters of cooling system has been multi-objectives optimized. On …the premise of meeting the pressure loss of the cooling system, the heat transfer efficiency has been improved, and then the output power of the motor has been increased. Show more

Keywords: YASA, cooling system, power density, CFD, pressure loss

DOI: 10.3233/JAE-190085

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-11, 2019

Authors: Ding, Li | Zhang, Jiasheng | Lin, Aiguo | Ge, Yulei

Article Type: Research Article

Abstract: In actual operation, the skin effect electric heat tracing system is powered by the inverter circuit, and the higher harmonic components are inevitably introduced. There is not much research on the influence of harmonic current on the electric heat tracing load loss. In this paper, the harmonic distribution under PWM driving mode is analyzed, and the load loss of the electric heat tracing body under harmonic current is derived. The co-simulation method of PWM inverter circuit and skin electric heat tracing body coupling is proposed. The simulation results of current and loss of co-simulation method and sine wave driving method …are compared. The results show that the parameters of PWM driving mode increase to different degrees, which proves the correctness of the joint simulation method. At the same time, the influence of the output characteristics and modulation parameters of the PWM inverter circuit on the load loss of the electric heat tracing body is analyzed, which provides a theoretical basis for the determination of the parameters of the inverter circuit. In addition, combined with multi-physics coupling analysis, this paper obtains more accurate temperature distribution results of the electric heat tracing system without scaling the size of the electric heat tracing ontology. Not only can we intuitively understand the material selection and hot spot configuration of the electric heat tracing components, but also further understand the influence of current harmonics on the load loss in actual operation, so as to better realize the efficient heat tracing of the skin electric heat tracing system. Show more

Keywords: Electric heat tracing system, harmonic analysis, loss calculation, co-simulation, multi-physics coupling analysis

DOI: 10.3233/JAE-190106

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-16, 2019

Authors: Li, Ke | Ling, Feng | Sun, Xiaodong | Cai, Yingfeng | Zhao, Dean | Yang, Zebin

Article Type: Research Article

Abstract: The traditional displacement sensors used in the bearingless induction motors (BIM) have many disadvantages, such as high cost, poor temperature stability, low conversion efficiency and complex motor operation. To improve these disadvantages, the detailed study on the novel displacement sensorless control based on the model reference adaptive system (MRAS) is presented in this paper. Firstly, the principle of radial suspension force generation and the mathematical model of the BIM are introduced. Secondly, the basic structure of the proposed MRAS is constructed and the stability is verified by the Popov’s integral inequality. Thirdly, to improve the control accuracy and dynamic characteristics …of sensorless vector control system, a method of directly controlling rotor eccentric displacement by using suspension force compensation is proposed. Finally, the feasibility and accuracy of the proposed method have been verified by the simulation and experimental results. According to the results obtained, the radial displacement of the rotor can be accurately estimated, and the rotor displacement sensorless control of the BIM based on MRAS is achieved. Show more

Keywords: Bearingless induction motor, model reference adaptive system, rotor displacement sensorless control, direct suspension force control

DOI: 10.3233/JAE-190118

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-19, 2019

Authors: Yao, Wang | Hai Tao, Yu | Rong, Guo | Dong Yang, Li | Ningjun, Feng | Zheng, Xu

Article Type: Research Article

Abstract: An extended state observer (ESO) based fuzzy adaptive sliding mode control (FASMC) for permanent magnet synchronous motor (PMSM) drive system is proposed in this paper. In order to improve the disturbance rejection property, a dynamic disturbance compensation method is developed based on extended state observer. A fuzzy adaptive sliding mode control method with a novel sliding mode reaching law is presented to enhance the tracking performance. Then, the proposed method called FASMC-ESO, is applied to regulate the speed of PMSM. The global asymptotic stability analysis of the system is proved by Lyapunov functions. Comparative simulation and experiment results verify the …effectiveness of the proposed method. Show more

Keywords: Disturbance observer (DO), permanent magnet synchronous motor (PMSM), fuzzy adaptive (FA), sliding mode control (SMC), extended state observer (ESO)

DOI: 10.3233/JAE-190098

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-17, 2019

Authors: Zuki, Nor Aishah Md | Othman, Raja Nor Firdaus Kashfi Raja | Ahmad, Suhairi Rizuan Che | Shukor, Fairul Azhar Abdul

Article Type: Research Article

Abstract: This paper discusses the constants in various types Double Stator Permanent Magnet Brushless DC Motor (DSPM BLDC). Hybrid or electrical vehicles requires fast response motor that are capable of reacting as soon as possible. Thus, the motor should have a faster time response with lower electrical time constant, T e and mechanical time constant, T m . However, there are few literatures that reported the time response for a double stator topology. The time response relates to various constant parameters of the motor. It is known that double stator has high torque density which can be implemented …for other applications in the future. For this research, various DSPM BLDC motors had been redeveloped. Finite Element Method (FEM) was used to simulate the characteristics of DSPM BLDC motor that considered the presence of the analytically calculated T e and T m . The results show that the Double Stator Slotted Rotor Permanent Magnet Brushless DC Motor (DSPM-SR) had good performance such as highest back emf, torque and good time response. A prototype of DSPM-SR had been manufactured and measured. The percentage differences between Analytical-FEM and Analytical-Mea for T e and T m were 4.2% and 9.1%, respectively. As a conclusion, this paper reveals the constants that could affect the performance of double stator topology. Show more

Keywords: Double stator, electrical time constant, mechanical time constant

DOI: 10.3233/JAE-190126

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-17, 2019

Authors: Zhou, Hongliang | Zhao, Wu | Zhang, Huiduan | Wang, Yanqin | Wu, Xuefeng | Sun, Zhijia

Article Type: Research Article

Abstract: Magnetorheological fluid (MRF) sealing technology has gained more and more attention in civil engineering, safety engineering, manufacturing, life science, aviation and so on, owing to its great pressure bearing capacity due to the viscous stress and controllable yield stress of MRF under external magnetic field. Even if overpressure occurs, magnetorheological seal (MRS) can restore the serviceability automatically with the help of magnetic field when pressure difference drops back. To have a deep understanding of magnetorheological sealing technique, the paper begins with an introduction of the basic features of MRF and relevant applications of MRS. Then several basic design issues of MRS structure are …introduced. Furthermore, main factors influencing MRS performance are discussed on how to increase the pressure drop of MRS structure. In the end, modeling techniques of MRS structure are provided according to Bingham plastic model, Bi-viscous model, Herschel–Bulkley model and Herschel–Bulkley model with preyield viscosity, respectively, for calculating yield stress of MRF and pressure drop of MRS structure. Hopefully, this review can be regarded as a useful complement to other reviews on MRF technology and applications. Show more

Keywords: Magnetorheological seal, magnetorheological fluid, structure, performance, modeling

DOI: 10.3233/JAE-190082

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-24, 2019

Authors: Iwamoto, Yuhiro | Nakasumi, Hayaki | Ido, Yasushi | Yamaguchi, Hiroshi

Article Type: Research Article

Abstract: Mn-Zn ferrite-based magnetic fluid is temperature-sensitive. Because of the low Curie temperature of Mn-Zn ferrite particles, magnetization is dramatically attenuated as the temperature rises. This temperature-dependent magnetization can be used to transport heat by magnetically driving a fluid via the application of a non-uniform magnetic field and heat. A potential application of this scheme is long-distance heat transport without the use of mechanical pumps. In the present work, a miniaturized magnetically-driven heat transport device with an inner diameter of 𝜙1.54 mm and a flow path length of 1,500 to 6,000 mm was fabricated. The influence of flow path length on the flow …rate induced by the magnetic body force was investigated experimentally and theoretically. Although the flow rate decreased with increasing flow path length due to friction loss, the driving pressure increased with rising heater temperature because of the temperature-dependent magnetization. The influence of flow path length on the driving pressure is relatively insignificant. An increase in the flow path length leads to effects that both attenuate and enhance the driving pressure. Substantial long-distance (6,000 mm) heat transport was realized by applying a non-uniform magnetic field and heat. Show more

Keywords: Magnetic nanofluid, heat transfer, magnetic fluid, temperature-dependent magnetization, energy conversion

DOI: 10.3233/JAE-190033

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-14, 2019