• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.981-983
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• 2000

Linear induction motors have static and dynamic end effects due to its finite core length, so that per-phase impedances are asymmetric and the air gap flux distribution is distorted. Because of these points the d-q equivalent circuit model considering both end effects has not been exactly completed. So this paper proposes a characteristic analysis method considering both static and dynamic end effect of the LIM. This method is to utilize asymmetric d-q equivalent circuit model with dynamic end effect coefficient. As a result, it is shown that the simulation results have a good agreement with experimental ones.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.876-878
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• 2000

In this paper, the characteristic of the Linear DC motor(LDM) are analyzed by using 3 Dimensional Equivalent Magnetic Circuit Network (3D EMCN), the movement of mover substitutes for the movement of magnetization in permanent magnet expressed by Fourier series, thrust characteristic analysis is performed and the appropriateness of analysed result is verified by comparing with the results of 2 Dimensional Finite Element Method (2D FEM) and experiment.

• Journal of Electrical Engineering and Technology
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• v.4 no.2
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• pp.229-233
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• 2009

This paper proposes a correction method for the error inherently created by time-step approximation in finite element analysis (FEA). For a simple RL and RLC linear circuit, the error in time-step analysis is analytically investigated, and a correction method is proposed for a non-linear system as well as a linear one. Then, for a practical inductor model, linear and non-linear time-step analyses are performed and the calculation results are corrected by the proposed methods. The accuracy of the corrected results is confirmed by comparing the electric input and output powers.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.7 s.262
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• pp.777-783
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• 2007

Since the performance of the circuit breaker mainly depends on the spring operating mechanism, the analysis of the spring operating mechanism is required. The spring, especially closing spring, stores the deformation energy due to the compression and then accelerates the big loads rapidly in the circuit breaker. To accurately carry out the kinematic and dynamic analysis of the circuit breaker, the precise modeling of the spring behavior is necessary. In this paper, the static stiffness of the spring is captured by using the tester. A simple mechanism similar to the spring operating mechanism was designed to generate the release motion of the spring. A high speed camera was used to capture the behavior of the spring. Three types of spring models such as a linear spring model, modal spring model, and nodal spring model are suggested and compared with the experimental results.

• Structural Engineering and Mechanics
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• v.60 no.2
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• pp.271-299
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• 2016

In this article, based on the higher-order shear deformation plate theory, buckling analysis of a rectangular plate made of functionally graded piezoelectric materials and its effective parameters are investigated. Assuming the transverse distribution of electric potential to be a combination of a parabolic and a linear function of thickness coordinate, the equilibrium equations for the buckling analysis of an FGP rectangular plate are established. In addition to the Maxwell equation, all boundary conditions including the conditions on the top and bottom surfaces of the plate for closed and open circuited are satisfied. Considering double sine solution (Navier solution) for displacement field and electric potential, an analytical solution is obtained for full simply supported boundary conditions. The accurate buckling load of FGP plate is presented for both open and closed circuit conditions. It is found that the critical buckling load for open circuit is more than that of closed circuit in all loading conditions. Furthermore, it is observed that the influence of dielectric constants on the critical buckling load is more than those of others.

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.9-10
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• 2015

EI core inductor in power electronic circuit simulation is usually assumed as linear by using matrix model. However, nonlinear magnetic characteristics such as B-H characteristic are also important for the accurate simulation of the circuit behavior. To model nonlinear magnetic characteristics of EI core inductor with only DC bias table, this paper presents a method in PLECS simulation tool which is a commercially available simulation tool for power electronics circuit analysis. Comparing with ideal matrix model, the simplification and accuracy are improved by this modeling method. Also, compared to analysis by FEM, it is much simpler, faster and easier to simulate with power electronics circuit. Validation of the proposed model was verified by simulation and experiment results.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.43-45
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• 1999

This paper is presented about the development of magnetic levitation conveyor with a transverse flux linear synchronous motor (TFLSM). The TFLSM is proposed as the new type linear motor for the conveyor driving system. The flux density distribution. the thrust and etc. of TFLSM are analyzed by the finite element method. To analyze the dynamic characteristics of TFLSM, the parameter of equivalent circuit is calculated by the analytical method.

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.3
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• pp.226-232
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• 2002

This paper explains a technique to improve the fault coverage of oscillation-test [1-5] for linear analog circuits. The transient behavior of the virtual ground is monitored during oscillation to extract information of the circuit. The limitation of the oscillation-test is analyzed, and an efficient signature analysis technique is proposed to maximize the fault coverage. The experimental result proves that the parametric fault coverage can be significantly increased by the proposed technique.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.2
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• pp.36-42
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• 2000

This paper presents the characteristics analysis of electromagnetic pump using linear induction motors. The electromagnetic pump is designed to transfer the molten metals by the electromagnetic force of linear induction motors. The characteristics f a linear induction motor are analysed by the equivalent circuit method considering the end effects. For the verification of the analysis method, the locked test and load test with molten tin were made. The test results of locked test were compared with the simulations, and the velocity of the load test with molten zinc showed 0.24[m/x] with air gap 30[gap] which is sufficient for transferring molten tin.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.22-24
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• 1997

The 4-pole LHSM was composed of the figure-of-eight shaped 3-phase armature windings. DC field windings, and the segmented secondary with the transverse bar track. The motor was designed on the base of the performance characteristic equations and the equivalent circuit model, with the coefficients of the magnetic shape. These coefficients were computed from the analytical expressions and examined from FEM analysis. The magnetic equivalent circuit of 3-D model of LHSM was obtained. and this concept provided the equivalent models for 2-D FEM analysis. Therefore, the airgap field, the lift and thrust force were calculated and compared with the results of magnetic equivalent circuit method.