International Journal of Applied Electromagnetics and Mechanics - Volume 33, issue 1-2

Authors: Song, Xiaochun | Jin, Zhisheng | Yu, Hao

Article Type: Research Article

Abstract: The uniform and steady bias magnetic field is the key to improvement of the transduction efficiency for the magnetostrictive guided-wave transducer. To optimize the magnetic circuit of the magnetostrictive transducer and obtain the best detection effects, the method to measure the homogeneity of magnetic flux density by sample standard deviation was studied. And the effects of such parameters as the thickness of the left and right enclosed magnetic conductor shell, the thickness of the outside round …shell of magnetic conductor, the distance between the bias magnetic exciting coil and the pipe's outer wall on the homogeneity of the excited bias magnetic field were analyzed quantitatively, both finite element simulation and experimental analysis were conducted to study the effects of different magnetic circuit design schemes on the excited bias magnetic field's homogeneity. The simulation results indicate that the homogeneity of the magnetic field is obviously improved with the above three parameters increasing, and the relatively uniform magnetic field can be obtained when the above parameters are all taken the maximum value of 20~mm. Show more

Keywords: Bias magnetic field, homogeneity, standard deviation, magnetostriction, guided wave

DOI: 10.3233/JAE-2010-1161

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 581-588, 2010

Authors: Jin, Sang-Min | Zhu, Yu-Wu | Lee, Sung-Hyung | Cho, Yun-Hyun

Article Type: Research Article

Abstract: sThe problem in improving the high positioning precision of permanent magnet linear synchronous motor (PMLSM) is the large detent force that is caused by the attraction between the permanent magnet (PM) and the iron core without input current. This detent force can be divided into two components: the slot effect and the end effect. In this paper we propose a novel method to reduce the detent force by employing the optimal designed auxiliary poles. To investigate …the characteristics of the detent force of PMLSM with auxiliary poles, the width, position, and height of auxiliary poles are chosen as the optimal factors and the two dimensional (2-D) finite element method (FEM) is used to predict to the values of detent force with different combinations of these three factors. And then the structure of auxiliary poles is optimized by the response surface method (RSM) through the fractional factorial design (FFD). Finally, the effectiveness of our proposed technique is verified by both the numerical calculations and experimental results. Show more

Keywords: Permanent magnet linear synchronous motor, detent force, optimal design, finite element method, response surface method

DOI: 10.3233/JAE-2010-1162

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 589-595, 2010

Authors: Zhang, Zhijun | Xu, Minglong | Feng, Bo | Zhang, Xinong

Article Type: Research Article

Abstract: A new inchworm-type piezoelectric actuator with round trip, variable step, large displacement is presented in this paper. It has two parts: the clamping structure, the pushing structure. Experiment system with high voltage drivers and closed-loop control system is designed. Dynamic model for piezoelectric actuator is built up. This actuator can move a displacement of ± 8 mm. Dynamic performance of the actuator is simulated by the MATLAB Simulink, and the results of simulation is in agreement …with that of the experiment in 30 nanometer accuracy demanded. Show more

Keywords: Inchworm, variable step, closed-loop, simulink

DOI: 10.3233/JAE-2010-1163

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 597-604, 2010

Authors: Zhu, Yu-Wu

Article Type: Research Article

Abstract: This paper proposes a novel technique to reduce the detent force in permanent magnet linear synchronous motor (PMLSM) using auxiliary poles. The detent force that is caused by the attraction between the permanent magnet (PM) and the iron core without input current can be divided into two components: the slot effect and the end effect. To reduce these two effects, we analyze the characteristics of the detent force according to semi-closed slot clearance length and auxiliary …poles position by using the two-dimensional (2-D) finite element method (FEM). The numerical calculations and the experimental results prove that this proposed technique has a good effect on the reduction of the detent force. Show more

Keywords: Permanent magnet linear synchronous motor, detent force, auxiliary poles, end effect

DOI: 10.3233/JAE-2010-1164

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 605-611, 2010

Authors: Wang, Haitao | Luo, Qiufeng | Cai, Jiahui | Zhang, Yajing | Wan, Junwei | Zhu, Yongkai | Tian, Gui Yun

Article Type: Research Article

Abstract: The principle of the inductance displacement sensor on optical aperture synthesis telescope is given with a measurement of mutual inductance to deduce the axial distance. It illustrates an effective modelling and calculation method based on Partial Element Equivalent Circuit (PEEC). PEEC is the method to calculate mutual inductances between coils utilizing partial parameter concept. Simulation for the change of mutual inductances is done which is prepared for the next step work.

Keywords: Optical aperture synthesis, mutual inductance, displacement sensor

DOI: 10.3233/JAE-2010-1165

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 613-620, 2010

Authors: Li, Jian | Cho, Yunhyun

Article Type: Research Article

Abstract: This paper presents the study of a high performance 3-Phase 3.7kW 2-Pole line start permanent magnet synchronous motor for pumping system. A method was proposed to study the starting torque characteristics considering line start with high inertia load. A direct-quadrate model including cage was built to study the synchronization capability. Two-dimensional transient finite element analysis was utilized for accurate calculation of efficiency, starting current speed curve and etc. Structural analysis was also conducted to study …the equivalent stress displacement of rotor at rated speed. Show more

Keywords: Line start permanent magnet synchronous motor, cage torque, braking torque, structural analysis, efficiency

DOI: 10.3233/JAE-2010-1166

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 621-628, 2010

Authors: Yuan, Qi | Ishikawa, Takeo | Oono, Masafumi

Article Type: Research Article

Abstract: In this paper, first the structure and composition of a new linear actuator with Soft Magnetic Composite material is presented. Next we study the simulation model of the linear actuator. By pole-placement design, the state-space model with a full-state feedback control is obtained. The result of simulation is given, and compared with the result of experiment. The results show that the two are basically the same.

Keywords: Actuator, analysis, SMC

DOI: 10.3233/JAE-2010-1167

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 629-637, 2010

Authors: Tagawa, Akihiro | Fujiki, Kazunari | Kojima, Fumio

Article Type: Research Article

Abstract: This paper presents development of a defect monitoring sensor using electromagnetic acoustic transducer (EMAT). The present study investigates the possibility of the defect monitoring using a new EMAT structure. The current EMAT was unsuitable for monitoring because of the large sensor area, and also it was necessary to have a mechanical scanning. Therefore, it was developed a new EMAT, smaller in size which does not need a mechanical scanning. The new EMAT was manufactured for a …trial purpose. Based on the result of the performance test, it was found out that the new EMAT is able to monitor a defect and also to monitor both a thin and thick piping wall. Show more

Keywords: Electromagnetic acoustic transducer (EMAT), halbach magnet structure, double coil

DOI: 10.3233/JAE-2010-1168

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 639-647, 2010

Authors: Yang, Byoung-Yull | Hwang, Kyu-Yun | Shin, Dong-Joo | Kwon, Byung-Il

Article Type: Research Article

Abstract: This paper introduces a rotor core in an interior permanent magnet type brushless DC motor. The rotor core consists of a rotor surface having a non-uniform air gap and a novel magnetic flux barrier. We show that, in the rotor core, the rotor surface having the non-uniform air gap effectively reduces the cogging torque while the optimized magnetic flux barrier reduces the cogging torque, and increases the average torque and the efficiency.

Keywords: Cogging torque, IPM type BLDC motor, taguchi method

DOI: 10.3233/JAE-2010-1169

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 649-654, 2010

Authors: Yang, Wenrong | Yang, Qingxin | Yan, Rongge | Liu, Suzhen | Yan, Weili

Article Type: Research Article

Abstract: A kind of magnetic fluid acceleration sensor (MFAS) is presented in the paper, which is using the magnetic and fluid characteristic of magnetic fluid. First, the output characteristics of MFAS and its static sensitivity are analyzed based on minimum potential energy principle, the result indicates the linear relationship between output voltage and acceleration. Then, the experimental research is carried out and compared with piezoelectric acceleration sensor simultaneity based on ZJY-601A experiment platform. The …output signal of MFAS is sampled and processed by the signal processing system, the output waveform demonstrate that the experimental results are both in agreement with theoretical analysis and output of piezoelectric acceleration sensor. Finally, system errors and influencing factors on measurement sensitivity are analyzed qualitative. Show more

Keywords: Magnetic fluid, acceleration sensor, dynamic response, permanent magnet

DOI: 10.3233/JAE-2010-1170

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 655-663, 2010