International Journal of Applied Electromagnetics and Mechanics - Volume 64, issue S1

Authors: Lasek, Pawel | Habelok, Krzysztof | Stepien, Mariusz

Article Type: Research Article

Abstract: The design considerations of AC machines with windings made of high-temperature superconductors (HTS) are presented in the following paper. The considerations were narrowed to permanent-magnet excited machines, although the results can be extrapolated to many other machine types as general guidelines. The influence of basic machine parameters and coefficients during the design of such machines are considered in order to estimate operating conditions of HTS windings. The number of poles, number of slots or slot dimensions, coil placement, and arrangement, are taken into account with the intent to fully utilize features of superconducting materials such as the capability of conducting …high current density without significant losses. The attention is placed on low power machines, below 1 kW, operating at liquid nitrogen temperature (77 K). For analysis purposes, the finite element method (FEM) is used to calculate the distribution of the magnetic field and its effect on the critical current of the HTS coil. The numerical analysis is carried out in ANSYS software. Show more

Keywords: Electric motors, high-temperature superconductors (HTS), finite element method (FEM)

DOI: 10.3233/JAE-209523

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. S1, pp. S269-S278, 2020

Authors: Habelok, Krzysztof | Lasek, Pawel | Stepien, Mariusz

Article Type: Research Article

Abstract: The influence of permanent magnet excitation on HTS coil in transverse-flux linear motor is analyzed. Numerical analysis using finite-element method is carried for two commonly used magnet arrays - alternating and Halbach. The influence of magnet arrangements on critical current density of HTS winding operating in temperature of liquid nitogen of 77 K is examined. The goal is to find optimal air gap size and magnet span to assure the best performance of the motor where anisotropy of superconductor is taken into account.

Keywords: Critical current density, electric linear motor, high-temperature superconductors (HTS), magnetic flux, permanent magnets

DOI: 10.3233/JAE-209524

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. S1, pp. S279-S286, 2020

Authors: Di Barba, Paolo | Dughiero, Fabrizio | Forzan, Michele | Lupi, Sergio | Mognaschi, Maria Evelina | Sieni, Elisabetta

Article Type: Research Article

Abstract: In industrial manufacturing process for tube production the stress relieving is achieved by heating the part to be treated at a very uniform temperature. In the paper, the optimized design of an inductor for stress relieving at temperature close to 600° is considered. The design of the inductor is initially performed by means an automated-design using optimization algorithms and objective functions that are minimized. In the range of obtained solutions, some of them appear more promising in terms of heating uniformity. Starting from these improved solutions, a technologically acceptable solution is proposed. This technological feasible solution is selected between the …ones obtained by means of a multi-objective optimization procedure and suitably adapted in order to achieve not only the technological targets but also a cost-effective design. Show more

Keywords: Multi-objective evolutionary optimization, multi-physics analysis, finite elements, induction heating

DOI: 10.3233/JAE-209525

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. S1, pp. S287-S296, 2020

Authors: Güney, Ömer Faruk | Çelik, Ahmet | Bozkurt, Ahmet Fevzi | Erkan, Kadir

Article Type: Research Article

Abstract: This paper presents the electromagnetic and mechanical analysis of an axial flux permanent magnet (AFPM) motor for high speed (12000 rpm) rotor which is vertically suspended by magnetic bearings. In the analysis, a prototype AFPM motor with a double-sided rotor and a coreless stator between the rotors are considered. Firstly, electromagnetic analysis of the motor is carried out by using magnetic equivalent circuit method. Then, the rotor disk thickness is determined based on a rotor axial displacement due to the attractive force between the permanent magnets placed on opposite rotor disks. Hereafter, an analytical solution is carried out to determine the …natural frequencies of the rotor-shaft system. Finally, 3D finite element analysis (FEA) is carried out to verify the analytical results and some experimental results are given to verify the analytical and numerical results and prove the stable high-speed operation. Show more

Keywords: Electromagnetic modeling, high speed, axial flux permanent magnet motor, mechanical stress analysis, rotor vibration analysis

DOI: 10.3233/JAE-209526

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 64, no. S1, pp. S297-S310, 2020