International Journal of Applied Electromagnetics and Mechanics - Volume 55, issue S1

Authors: Kawaguchi, Kohei | Takahashi, Yasuhito | Fujiwara, Koji | Matsushita, Makoto | Takahashi, Norio | Tokumasu, Tadashi

Article Type: Research Article

Abstract: In order to develop a highly efficient motor, it is important to understand the influence of manufacturing processes on the resulting magnetic properties of magnetic materials. The deterioration of magnetic properties of laminated cores due to the welding significantly depends on its process. Therefore, the deterioration of magnetic properties upon the welding process has to be evaluated so as to calculate the iron losses using numerical simulation accurately. First, the iron losses of a single punched steel sheet and stator cores in which some punched steel sheets are stacked and welded are measured. Next, differences of these results are compared …to evaluate the influence of welding process. It is confirmed that the lager the number of welding parts is, the larger the deterioration of magnetic properties becomes. Finally, the validity of the measurements is discussed based on iron loss calculations using the finite element method (FEM). Show more

Keywords: Stator core, punched steel sheet, welding, deterioration of magnetic properties

DOI: 10.3233/JAE-172271

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. S1, pp. 169-176, 2017

Authors: Li, Yongjian | Wang, Lixiang | Yang, Qingxin | Zhu, Jianguo | Zhang, Changgeng

Article Type: Research Article

Abstract: In this paper, a novel three-dimensional (3-D) magnetic tester with symmetrical orthogonal excitation structure and cubic field-metric sensing structure is designed and analyzed. Automatic measurement system, which includes feedback control method, harmonics compensation, and automatic data processing is developed for the 3-D magnetic tester. In order to improve the measurement precision, cross effects of the magnetic fields in three principal directions are concerned, and error mitigation methods which fit for different excitation models are proposed. Magnetic properties of typical grain-oriented (GO) and non-grain-oriented (NGO) laminated silicon steel specimens under alternating and rotating excitations are measured and analyzed by using the …designed 3-D magnetic tester. Show more

Keywords: Laminated silicon steel, 3-D magnetic tester, automatic measurement system, dynamic magnetic properties, rotating excitation

DOI: 10.3233/JAE-172272

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. S1, pp. 177-191, 2017

Authors: Zhou, Hang | Zhang, Yanli | Zhang, Dianhai | Ren, Ziyan | Xie, Dexin

Article Type: Research Article

Abstract: In this paper, the dynamic magnetostriction of the electrical steel sheet is measured by a triaxial strain gauge based on a single-sheet tester under the alternating magnetic flux condition. The anisotropic magnetostriction property is analyzed, and an improved back propagation neural network assisted model is applied to model the anisotropic principal strain of magnetostriction along different excitation directions. To keep the evaluation cost at an acceptable level, the Levenberg-Marquardt algorithm combined with particle swarm optimization is developed. Finally, the proposed model is verified by comparing the measured magnetostriction and computed one.

Keywords: Anisotropic magnetostriction, electrical steel, BP neural network, alternating magnetization

DOI: 10.3233/JAE-172273

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. S1, pp. 193-201, 2017

Authors: Le, Minhhuy | Kim, Jungmin | Kim, Jisoo | Do, Hwa-Sik | Lee, Jinyi

Article Type: Research Article

Abstract: This paper presents an electromagnetic testing method for moisture separator reheater (MSR) tubes, which is based on partial saturation eddy current testing (PSECT). The sensor probe has a permanent magnet that is used to partially saturate the MSR tube material, a bobbin coil is used to supply an alternating electromagnetic field that penetrates into the tube, and a bobbin-type integrated Hall sensor (BIHaS) array is used to measure the radial component of the electromagnetic field distribution in the tube. The BIHaS has 15 Hall sensor elements arrayed at 24 ∘ (2.72 mm) intervals on the circumference …to make a 13.5 mm diameter sensor probe. Thus, the spatial resolution of measurement can be improved rather than using a single/differential-type sensing coil as used in conventional PSECT systems. The efficiency of PSECT over magnetic flux leakage testing and eddy current testing is presented. Furthermore, the quantitative evaluation of damage volume can be performed. Show more

Keywords: Hall sensor array, partial saturation eddy current testing, electromagnetic testing, moisture separator reheater

DOI: 10.3233/JAE-172274

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. S1, pp. 203-209, 2017

Authors: Kim, Jungmin | Le, Minhhuy | Hong, Wanpyo | Lee, Jinyi

Article Type: Research Article

Abstract: This paper presents a nondestructive testing method for bleed air duct tubes in aging aircrafts. The inspection technique is based on eddy current testing. The sensor probe is constructed of a bobbin coil as a magnetic source and a bobbin-type integrated Hall sensor (BIHaS) array to measure the electromagnetic field distribution around cracks on the bleed air duct tube. The BIHaS has many Hall sensor elements arrayed in a circumference that can measure the radial component of the electromagnetic field with high spatial resolution. For example, 45 Hall sensor elements were used for inspection of a bleed air duct tube …having an inner diameter of 38 mm. To verify the effectiveness of the proposed system, tests were carried out on artificial cracks in bleed air duct tubes. The system was able to inspect 3 mm long cracks and their length was quantitatively evaluated with 1.57 mm of standard deviation. Show more

Keywords: Control rod, encircling coil, eddy current, sensor array, small-bore piping system, magnetic camera, imaging

DOI: 10.3233/JAE-172275

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. S1, pp. 211-216, 2017

Authors: Zhu, Lihua | Li, Yang | Yang, Yimei | Yang, Qingxin | Zhang, Xin

Article Type: Research Article

Abstract: Controllable saturable reactor (CSR) has been developed rapidly because of its continuous adjustable output characteristics. However, the vibration of the saturated core is serious and becomes a bottleneck problem in its application. Electromagnetic vibration analysis become an essential part in designing and manufacturing. In this paper, the electromagnetic vibration of cores and windings of CSR under actual working conditions was numerical calculated and measured. In order to obtain the magnetic properties, magnetization curves under DC bias were got through repeated measuring with different setting and simple calculation. Magnetostriction (MS) was measured by laser interferometer under DC bias. Based on the …measured properties under different DC control current, magnetic field was firstly analyzed and the magnetic forces, which include Lorentz, Maxwell and magnetostrictive force, were calculated. Then the vibration of cores and windings due to electromagnetic forces were calculated by using a weak 3D magneto-elastic model under actual working conditions. Finally, the vibration of a CSR, which is a single-phase prototype with 4.4 kVar/220 V, were tested and analyzed. The error between measurement and calculation results is in a reasonable range. Show more

Keywords: Controllable saturable reactor, electromagnetic vibration, DC control current, magnetostriction

DOI: 10.3233/JAE-172276

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 55, no. S1, pp. 217-227, 2017