• Journal of the Korean Society for Precision Engineering
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• v.21 no.12
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• pp.37-43
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• 2004

The performance of magnetic abrasive finishing fur surface is evaluated by the characteristic curve. The characteristic curve is generated by experiment in surface finishing. For experiment, new magnetic inductor is designed and manufactured. 15 kinds of powders are provided to find the relationship between powder characteristic and finishing performance. As powder, Fe-TiC. Polymer-TiC and Fe-NbC are used with different size. The size of abrasives and location are also important factor for the performance. From characteristic curve, two index are obtained, which specify the initial finishing performance and endurance of finishing performance. It is proved that the performance index can be applied to select proper powder for efficient deburring. It is shown that the characteristic curve can be used as good tools for evaluating powder performance in surface finishing and deburring.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.128-130
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• 2002

This paper describes the operating characteristic analysis of magnetic actuator that is used in breaker using 3-D axisymmetry finite element method. To analyze the operating characteristic of magnetic actuator for configuration change is designed an A, B model and C. Also, For Transient analysis of Electromagnetic system is considered Non-linear characteristic for magnetizing of iron. The analysis results of A, B model and C for magnetic actuator compared with those characteristic respectively.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.857-859
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• 2002

This paper describes an analysis of Magnetic actuator with permanent magnet using 2-D axisymmetric finite element method. Magnetic actuator is the machine to change electrical signal into mechanical signal, and fast switching device to be used for breaker and automation field etc. This magnetic actuator considered action for armature distance, external circuit, and nonlinear material characteristic and current. Also, comparative analysis is performed for 2 coil type and 1 coil type by coil type of actuator, then characteristic is grasped. It is Combined with external circuit for analyzing transient characteristic by variable time. According to the results, we analyzed action characteristic of Magnetic actuator.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.3
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• pp.236-243
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• 2008

This paper analyses magnetic flux saturation of matching transformer considering characteristic of dynamic voltage restorer(DVR) system to solve voltage sags which are considered the dominant disturbances affecting power quality. This DVR consist of PWM inverter to inject arbitrary voltage, LC low pass filter and matching transformer for isolation and grid connection. However, the matching transformer has an excess of inrush current by magnetic flux saturation in the core of transformer. Due to this inrush current, the rating of matching transformers is double for needed nominal rating for protection of DVR. Therefore, in this paper, an advanced modeling method of magnetic flux saturation is used to analyze a magnitude and characteristic of magnetizing current. Simulation and experimental results considering characteristic of DVR system are provided to demonstrate the validity of the proposed analysis method.

• International Journal of Railway
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• v.3 no.1
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• pp.14-18
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• 2010

This paper describes design and characteristic analysis of long primary type linear synchronous motor (LSM) for high speed train system. LSM is designed using loading distribution method and magnetic equivalent circuit. For characteristic analysis of LSM, analytical and numerical methods are applied. Analytical method for solving the magnetic field distribution of the analytic model is based on the Maxwell’s equations. Using the characteristic equation and magnetic equivalent circuit, we analyze the effect of variation of parameters, and then we validate the result by comparing with numerical method by finite element method (FEM). We compare the analytical method with numerical method for analyzing the effect by variable parameters. This result will be useful of design and forecast of performance without FEM.

• Progress in Superconductivity and Cryogenics
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• v.8 no.3
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• pp.59-62
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• 2006

For electric power applications of Bi-2223/Ag superconducting tapes, a transport characteristic is important issue. A transport characteristic is strongly depends on the magnitude and direction of external time-varying magnetic field. To verify a effect of external magnetic field, we manufactured a prototype magnet and obtained transport characteristics with respect to the magnitude, the direction and the frequency of external magnetic field. The data acquired in this paper will be used as a source for the study of HTS electric power applications which is supposed to carry on.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.25-27
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• 1998

In this paper electromagnetic force and its distribution are analyzed on the nonlinear magnetic materials by Finite Element Method. Most of magnetic materials have the nonlinear characteristic, which considerably effects on the magnetic system. And it is necessary to know its distribution at the every Part of the magnetic material in order to design the, magnetic system considering noise, vibration and strain characteristic. The results are obtained by Maxwell stress. virtual work and magnetic charge method and compared with one another.

• Progress in Superconductivity and Cryogenics
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• v.16 no.1
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• pp.27-31
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• 2014

2G HTS tapes are widely used for various electric machines. In addition, stacked or parallel connected HTS tapes are essentially used to raise transport current level for large capacity electric machines. Therefore, critical current characteristic of stacked tapes need to be studied. Recently developed 2G HTS tapes are fabricated with various defects doping so that tapes possess pinning center to improve the critical current characteristic. During this process, the critical current is determined minimum value in not perpendicular magnetic field but a specific magnetic field angle according to the reported research. However, the effects of magnetic field angle to critical current of multi-stacked 2G HTS tapes have not been examined. In this paper, field coil which is a race-track coil wound by using an HTS tape with iron-core was fabricated to apply angle adjustable magnetic field to the 2G HTS tape samples. We measured critical current of single and multi-stacked two tapes that have different characteristic depending on various magnetic field angle and magnitude in liquid nitrogen environment. Furthermore, results of single and multi-stacked tapes were compared and analyzed.

• Journal of Magnetics
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• v.18 no.2
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• pp.111-116
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• 2013

This paper presents a characteristic analysis method of a permanent magnet type transverse flux linear motor (TFLM) with spiral cores. The spiral cores are used as the mover cores in order to make 3-dimensional (3-D) magnetic flux paths at the TFLM which have 3-D magnetic flux flows. The 3-D Equivalent Magnetic Circuit Network Method is used to analyse the magnetic characteristics of the machine, and an imaginary part, 'flux barrier,' is introduced to consider the spiral core characteristic. Magnetic parameters such as flux, inductance, and thrust are calculated from the analysis results. The computed thrust forces are compared to measured values to confirm the accuracy of the analysis.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.253-255
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• 2000

This paper describes the operating characteristic analysis of PM-type magnetic circuit breaker for electromagnetic field, electric circuit and mechanical motion problems. Transient calculations based up 2D finite element magnetic field solution including non-linearity of materials. Change of dynamic characteristic from eddy current in mover is quantified from FEM analysis.