International Journal of Applied Electromagnetics and Mechanics - Volume 73, issue 2

Authors: Permata, Diah | Widyawati, Widyawati | Sinaga, Herman H. | Purwasih, Nining | Widiarto, Sonny

Article Type: Research Article

Abstract: Natural fiber composite becomes a necessity encountering the issue of eco-friendly materials. The application of natural fiber composite as electromagnetic interference (EMI) shielding enclosures has not been studied extensively. This study aims to investigate the performance of the coconut fiber composite as EMI shielding enclosure material. Enhancement of the electrical volume-conductivity of the composite was made by polymerization of coconut fiber with polyaniline and doping the multiwall carbon nanotubes to epoxy resin. Three types of composites were made with different weight percentages of coconut fiber: 5, 10, and 15 wt%. The highest volume-conductivity and shielding effectiveness of coconut fiber composite …are 0,0458 S/m and −7.69 dB from the highest weight percentage of coconut fiber (15 wt%). While the highest tensile strength (26.78 MPa) resulted from the lowest weight percentage (5 wt%). This study shows the coconut fiber composite could potentially be the material of EMI shielding enclosure though their electrical conductivity and tensile strength should be increased. Show more

Keywords: Coconut fiber, natural composite, enclosure, conductivity, shielding effectiveness

DOI: 10.3233/JAE-220295

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 73, no. 2, pp. 73-80, 2023

Authors: Zhao, Haining | Yu, Shenbo

Article Type: Research Article

Abstract: In this paper, the distribution of the air gap magnetic field in the motorized spindle is obtained through theoretical derivation, which is verified by comparing with the finite element simulation results. Based on the original calculation of air gap magnetic field, the rotor eccentricity theory is added, and the distribution of air gap magnetic field after rotor eccentricity is obtained. The correctness of the calculation theory of eccentric air gap magnetic field is verified by the finite element simulation results. Through the electromagnetic force calculation and finite element simulation of asymmetric magnetic field in eccentric state, the influence law of …unbalanced electromagnetic force on the fatigue life of motorized spindle rotor is summarized. Show more

Keywords: Motorized spindle, rotor eccentricity, unbalanced magnetic pull, fatigue life

DOI: 10.3233/JAE-220236

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 73, no. 2, pp. 81-96, 2023

Authors: Hou, Peng | Ge, Baojun | Tao, Dajun | Pan, Bo | Zhao, Liping

Article Type: Research Article

Abstract: The linear speed of the rotor surface of high speed permanent magnet motor (HSPMM) is as high as 100 m/s, and the air friction loss on the rotor surface is much higher than that of ordinary motors, accounting for a large proportion of the total loss, and the actual air friction loss on the rotor surface is much higher than that of ordinary motors. It is extremely difficult to directly measure and verify the size of the rotor surface. At the same time, the air friction loss on the rotor surface is related to various factors such as motor speed, air …gap structure and rotor surface roughness. It is difficult to accurately calculate through theoretical analysis and analytical methods. Based on the 3D fluid field physical model, this paper analyzes the relationship between the rotor air friction loss of FeCo based HSPMM and the rotor speed, rotor geometry, surface roughness and axial wind speed. Based on HSPMM, the calculation and test method of rotor surface air friction loss are studied. Through the FeCo based HSPMM no-load test, according to the relationship between the rotor air friction loss and other losses and the motor speed, the rotor surface air friction loss can be separated from the total loss. The experimental results are consistent with the calculated values, indicating that the HSPMM rotor air friction loss calculation method based on 3D fluid field analysis is effective. Show more

Keywords: Air friction loss, 3D fluid field, Fluid mechanics, HSPMM, Loss separation

DOI: 10.3233/JAE-230030

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 73, no. 2, pp. 97-110, 2023

Authors: Du, Yunlu | Huang, Yunkai | Guo, Baocheng | Zhu, Zichong | Peng, Fei | Dong, Jianning

Article Type: Research Article

Abstract: In this article, an efficient multi-objective optimization strategy for the Halbach array permanent magnet synchronous machine (PMSM) is developed by taking into consideration the nonlinear B-H behavior of soft magnetic materials. Based on the harmonic modeling (HM) technology, the electromagnetic performances (EPs) of the Halbach array PMSM can be computed. To specifically model the local magnetic saturation, the stator teeth are separated into several annular layers, and each tooth is further divided into several regions along the tangential direction. Then, the parameters of the Halbach array PMSM are optimized utilizing combined nonlinear semi-analytical model (SAM) and non-dominated sorting genetic algorithm …II (NSGA-II). To validate the effectiveness and accuracy of the developed optimization scheme, a Halbach array prototype is then manufactured in accordance with the optimization results. The multi-objective rapid optimization strategy developed in this article, which includes but is not limited to Halbach array permanent magnet (PM) machines, serves as a reference for the design and optimization of various PM machines. Show more

Keywords: Halbach array, permanent magnet synchronous machine (PMSM), magnetic saturation, non-dominated sorting genetic algorithm II (NSGA-II)

DOI: 10.3233/JAE-230029

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 73, no. 2, pp. 111-128, 2023

Authors: Fang, Hongwei | Li, Ziyan

Article Type: Research Article

Abstract: The application of coaxial magnetic gear (CMG) in wave generator instead of traditional variable speed gearbox can effectively improve torque density and reduce torque ripple. Thus, the operation principle of CMG from the perspective of magnetic field modulation is firstly analyzed in this paper. Then the air gap magnetic fields induced by high-speed and low-speed rotors are studied. And the radial height, inner diameter angle, and outer diameter angle of the modulating pieces (MPs) are optimized by using the combination of response surface method (RSM) and particle swarm optimization (PSO) algorithm to improve the torque transmission capacity of CMG. The …CMG is combined with the permanent magnet synchronous machine to get the magnetic-gear permanent magnet synchronous generator (MG-PMSG). The design feasibility of the MG-PMSG is verified from four aspects: static magnetic field analysis, no-load characteristics, load characteristics and load disturbance analysis. Show more

Keywords: Coaxial magnetic gear, magnetic-gear PMSG, torque, particle swarm optimization, parameter optimization

DOI: 10.3233/JAE-220082

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 73, no. 2, pp. 129-151, 2023