• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.109-111
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• 2002

It requires to study on accurate control skill for the technical improvement of servo system require. It needs to study on brake that has constant-torque speed range as load. In this paper, braking torque of eddy current brake between electromagnet stator and rotating disk are analyzed. The torque-speed characteristics and proper disk construction are presented in here. From the computer simulation results, it was found that eddy current braking torque is linear or approximately constant over the desired speed range depending on the rotor material, disk construction, pole number and pole displacement of stator, these are confirmed by experimental results.

• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.46-48
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• 2002

It needs to study on proper brake performance used in servo system of industrial application. In this study, braking torque of eddy current brake between electromagnet stator and rotating disk are analyzed. The torque-speed characteristics and proper disk construction are presented in this paper. From the computer simulation results, it was found that eddy current braking torque is linear or approximately constant over the desired speed range depending on the rotor material, disk construction, pole number and pole displacement of stator.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.642-647
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• 1994

This paper describes some research works of computer-aided design of blanking & piercing progressive die for stator and rotor parts by the press. An approach to the system is based on knowledge based rules. The developed system is composed of five main modules such as input & graphic interface, blanking feasibility check, strip layout, die layout and output module. Using this system, design parameters (geometric shapes, die generated in dimensions and dimensions of tool elements) are determined and output is generated in graphic form. Knowledges for tool design are extracted from the plasticity theories, handbooks, relevent references and empirical know-hows of experts in blanking companies. The developed system provides powerful capabilities for process planning and die design of stator and rotor parts.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.8
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• pp.675-683
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• 2004

The motor current signature provides an important source of the information for the faults diagnosis of three-phase induction motor. The theoretical principles behind the generation of unique signal characteristics, which are indicative of failure mechanisms, are Presented. The fault detection techniques that can be used to diagnose mechanical Problems, stator and rotor winding failure mechanisms, and air-gap eccentricity are described. A theoretical analysis is presented which predicts the presence of unique signature patterns in the current that are only characteristics of the fault. The predictions are verified by experimental results from a special fault Producing test rig and on-site tests in a steel company. And this study have made new diagnostic algorithm for the operating induction motors with the test results. These developments are including the use of monitoring and analysis of electric current to diagnose mechanical and electrical problems and gave the precise test results automatically.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.3
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• pp.105-109
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• 2001

In this paper, the windmill type ultrasonic motors with 11.35 mm diameter, 2.87 mm thickness of metal endcap and 1.47 g weight were fabricated. Effects of slots and thickness on torque characteristic in the windmill type ultrasonic motor were investigated, when stator's slots were changed from 4, 6, 8 and thickness 0.15 mm, respectively. Specially designed metal endcaps with windmill shaped cutting can provide longitudinal and torsional displacements simultaneously as the ceramic disk vibrates radically. The windmill type ultrasonic motor has only three components: a stator element with windmill shape slotted metal endcap, a rotor and bearing. Ultrasonic motor stimulated to ultrasonic oscillations by piezoelectrics to drive a rotor via friction contact. The ultrasonic motor fabricated here was the windmill type ultrasonic motor operated by single-phase AC source. Bidirectional revolution using single-phase high frequency for driving the ultrasonic motor was presented.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.11
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• pp.612-615
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• 2002

The main advantages of Disk type Single-Phase Switched Reluctance Motor (DSPSRM) is the simple construction, rugged structure, low manufacturing cost and simple driving circuit. It is especially possible to make the short axial length of DSPSRM. Therefore, it is suitable to setup this motor in a narrow space. This paper presents the shape design to maximize the average torque of DSPSRM that is achieved by 3D Finite Element Method (3D FEM) considering the nonlinear of magnetic material. The characteristics of two different rotor shapes are compared. The design parameters, such as the rotor and stator pole arc, are selected to the parametric study. The effect of pole arc ratios on the torque performance is investigated. From these results, the optimal pole arc to produce the maximum torque is determined.

• Journal of Electrical Engineering and information Science
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• v.2 no.4
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• pp.79-85
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• 1997

A unified, modular and decoupled approach for the simulation of converter fed induction machine systems is presented. The system under consideration could have semiconductor devices connected to the stator or the rotor of the induction machine for the purpose of controlling its performance. The machine model, however is invariant to these aspects. The model spans the circuit and equation domains of description thus allowing he advantages of both these domains of descriptions to be utilized. The results obtained using this machine and switch model for a VSI fed induction machine (stator fed, rotor shorted0 are compared with those from laboratory experiment to establish the validity and accuracy of th approach. Results for a slip energy recovery system are also presented and compared with those of earlier workers to establish the performance of the models and algorithms in he doubly-fed mode of operation of induction machine systems.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.3
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• pp.347-353
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• 2012

Design and analysis of a novel 2-phase 4/5 Switched Reluctance Motor(SRM) is presented. The proposed motor employs a novel stator pole configuration. A novel SRM employs four-rotor and five-stator poles. The motor has no dead-zone and can be operate at any rotor position. The structure and operating principle are also described. The comparison between the proposed motor and a conventional two-phase 4/2 SRM is undertaken in this analysis. Furthermore, the Finite Element Analysis(FEA) and matlab-simulink are used to predict and simulate the performance of a proposed motor. The results of investigation indicate that the proposed structure offers a better performance in term of torque production.

• The KSFM Journal of Fluid Machinery
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• v.20 no.2
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• pp.41-46
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• 2017

The flotation performance of the induced gas flotation (IGF) machine is considerably influenced by geometric configurations of rotor and stator. The interaction of rotor and stator, which are the most important components in IGF, serves to mix the air bubbles. Thus, the understanding of flow characteristics and consequential analysis on the machine are essential for the optimal design of IGF. In this study, two-phase (water and air) flow characteristics in the forced-air mechanically stirred Dorr-Oliver flotation cell was investigated using ANSYS CFX. In addition, the void fraction and the velocity distributions are determined and presented with different blade configurations.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.22-24
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• 1998

The Synchronous reluctance motor is a sinewave ac motor and it has cylindrical surfaces on both sides of the air gap. The stator is a conventional polyphase ac stator, while the rotor has internal flux barriers shaped to maximize the ratio of d-axis to g-axis reactance. This paper presents the finite element analysis and parameter measurement of the synchronous reluctance motor(SRM). The model motor is a 3-phase SRM with the segmental rotor and its rating is 0.175kw. The torque characteristic is analysed by finite element method and compared with that from measurement.