• 제목/요약/키워드: Electro-magnetic Induction

검색결과 65건 처리시간 0.023초

회전자 편심을 고려한 농형 유도전동기의 특성해석 (Characteristics Analysis on the Effects of Rotor Eccentricity in Squirrel-cage Induction Motor)

  • 김미정;김병국;황돈하;강동식;조윤현
    • 전기학회논문지
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    • 제56권2호
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    • pp.289-294
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    • 2007
  • This paper describes the effects of rotor eccentricity in squirrel cage induction machines. Asymmetric electro-magnetic force caused by the frictional worn bearing, rotor misalignment and unbalanced rotor etc. generates an asymmetrical operation, vibration and electro-magnetic noise. The need for detection of these rotor eccentricities has pushed the development of monitoring methods with increasing sensitivity and noise immunity. In this paper, we focus on investigating the asymmetrical operation considering of unbalanced magnetic pull in squirrel-cage induction motor with 380 [V], 7.5 [kW], 4P, 1,768 [rpm]. The effects of the non-symmetric rotor and magnetic force are simulated by finite element method (FEM) and tested using search coils for measuring the actual air-gap flux.

농형 유도전동기의 회전자 편심에 따른 특성분석 (Analysis of Squirrel Cage Induction Motors with Rotor Eccentricity)

  • 김미정;김병국;문지우;조윤현;황돈하;강동식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.825-826
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    • 2006
  • This paper describes the effects of air gap eccentricity in induction machines. Asymmetric electro-magnetic force caused by the frictional worn bearing, rotor misalignment and unbalanced rotor etc. generates an asymmetrical operation, vibration and electro-magnetic noise. In this paper, we focus on investigating the asymmetrical operation considering of unbalanced magnetic force in squirrel-cage induction motor with 380 [V], 7.5 [kW], 4P, 1,768 [rpm]. The effects of the rotor eccentricity, magnetic force are investigated by finite element method (FEM) and experiment. The results can be useful for on-line monitoring of an induction motor.

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회전자 편심을 고려한 농형 유도전동기의 특성해석 (Characteristics Analysis on the Effects of Rotor Eccentricity in Squirrel-cage Induction Motor)

  • 김미정;김병국;조원영;조윤현;황돈하;강동식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.188-190
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    • 2006
  • This paper describes the effects of air gap eccentricity in induction machines. Asymmetric electro-magnetic force caused by the frictional worn bearing, rotor misalignment and unbalanced rotor etc. generates an asymmetrical operation, vibration and electro-magnetic noise. The need for detection of these rotor eccentricities has pushed the development of monitoring methods with increasing sensitivity and noise immunity. In this paper, we focus on investigating the asymmetrical operation considering of unbalanced magnetic force in squirrel-cage induction motor with 380 [V], 7.5 [kW], 4P, 1,768 [rpm]. The effects of the rotor eccentricity, magnetic force are investigated by finite element method (FEM).

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TR 단조를 위한 유도 가열 공정의 전력제어 (Power Control of Induction Heating Process for TR forging)

  • 송민철;주성호
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 추계학술대회논문집
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    • pp.230-233
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    • 2004
  • The purpose of this study is to establish the optimal induction heating conditions of various preform types used for TR forging. The finite element model coupled electro-magnetic and transient heat transfer was employed to evaluate the distribution of temperature at the billet. Power control method was applied to control temperature of preform in induction heating because TR forging is not a continuous process. Power schedule that consists of heating and holding stage was suggested. In heating stage, power is inversely proportional to diameter of preform but the time of heating stage is directly proportional to the diameter of preform. But, in holding stage, the required power for thermal equilibrium per unit volume of the billet decreases with an increase in a diameter of billet due to the increase of efficiency.

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자동차용 중공 구동축의 고주파 경화 공정에 대한 수치적 연구 (Numerical Simulation of Induction Hardening Process of Tubular Drive Shaft for Automobile)

  • 강경필;오병기;김용환
    • 소성∙가공
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    • 제25권4호
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    • pp.248-253
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    • 2016
  • Induction hardening process of tubular drive shaft for automobile is simulated by combining the thermal, mechanical, electro-magnetic and metallurgical analysis models. Various material properties for each analysis model are obtained in a consistent way via material properties calculation software, JMatPro®. To consider the scanning process of induction heating, boundary element method is adopted for electro-magnetic field calculation. The distribution of temperature, stress and phase volume fraction are tracked out through the whole process and the effect of scanning velocity is reviewed. The analysis result shows that the critical principal stress is developed at the phase boundary where martensite is formed.

유도가열을 이용한 강판성형공정에서 유도코일 형상의 효과 (Effects of Inductor Shape in Steel Forming Process with High Frequency Induction Heating)

  • 양영수;배강열;신희윤
    • Journal of Welding and Joining
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    • 제26권4호
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    • pp.66-72
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    • 2008
  • Because of high intensity and easy controllability of the heat source, high frequency induction heating has been concerned and studied for the steel forming process in the ship building industry. However, the heating and forming characteristics have to be further properly modelled and analyzed for the process to be utilized with its optimal working parameters. In this study, a modelling with thermo-elasto-plastic analysis is performed using the FEM to study heat flow and deformation of the steel plate during the forming process with the electro-magnetic induction heating. The numerical model is then used to study the effect of the inductor shape on the magnitude of angular deformation of the plate during the forming process. It is revealed that the square shape of inductor induces the largest deformation among the rectangular inductors.

ANALYSES OF ANNULAR LINEAR INDUCTION PUMP CHARACTERISTICS USING A TIME-HARMONIC FINITE DIFFERENCE ANALYSIS

  • Seong, Seung-Hwan;Kim, Seong-O
    • Nuclear Engineering and Technology
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    • 제40권3호
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    • pp.213-224
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    • 2008
  • The pumping of coolant in a liquid metal fast reactor may be performed with an annular linear induction electro-magnetic (EM) pump. Linear induction pumps use a traveling magnetic field wave created by poly-phase currents, and the induced currents and their associated magnetic field generate a Lorentz force, whose effect can be the pumping of the liquid metal. The flow behaviors in the pump are very complex, including a time-varying Lorentz force and pressure pulsation, because an induction EM pump has time-varying magnetic fields and the induced convective currents that originate from the flow of the liquid metal. These phenomena lead to an instability problem in the pump arising from the changes of the generated Lorentz forces along the pump's geometry. Therefore, a magneto-hydro-dynamics (MHD) analysis is required for the design and operation of a linear induction EM pump. We have developed a time-harmonic 2-dimensional axisymmetry MHD analysis method based on the Maxwell equations. This paper describes the analysis and numerical method for obtaining solutions for some MHD parameters in an induction EM pump. Experimental test results obtained from an induction EM pump of CLIP-150 at the STC "Sintez," D.V. Efremov Institute of Electro-physical Apparatus in St. Petersburg were used to validate the method. In addition, we investigated some characteristics of a linear induction EM pump, such as the effect of the convective current and the double supply frequency (DSF) pressure pulsation. This simple model overestimated the convective eddy current generated from the sodium flow in the pump channel; however, it had a similar tendency for the measured data of the pump performance through a comparison with the experimental data. Considering its simplicity, it could be a base model for designing an EM pump and for evaluating the MHD flow in an EM pump.

강판의 유도가열에서 공정변수가 온도 및 자속분포에 미치는 영향에 관한 연구 (A Study of the Effects of Process Variables on Temperature and Magnetic-flux Distribution in Induction Heating of Steel Plate)

  • 배강열;이태환;양영수
    • Journal of Welding and Joining
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    • 제19권5호
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    • pp.526-533
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    • 2001
  • Induction heating of float metal products has an increasing importance in many applications, because it generates the heat within workpiece itself and provides high power densities and productivity. In this study, the induction heating of a steel plate to simulate the line heating is investigated by means of the Finite Element Analysis of the magnetic field and temperature distribution. A numerical model is used to calculate temperature distribution within the steel plate during the induction heating with a specially designed inductor. The effects of materital properties depending on the temperature and magnetic field are taken into consideration in an iterative manner. The simulation results show good magnetic field with experimental data and provide good understanding of the process. Since the numerical model demonstrates to be suitable for analysis of induction heating process, the effects of air gap and frequency on magnetic-flux and power-density distribution are also investigated. It is revealed that these process parameters have an important roles on the electro-magnetic field and power-density distribution governing the temperature distribution of the plate.

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IGBT 인버터구동 유도전동기의 회전자 편심 특성 해석 (Analysis of IGBT Inverter controlled Squirrel Cage Induction Motor during Eccentricity Rotor Motion)

  • 김미정;김병국;문지우;조윤현;황돈하;강동식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1055-1056
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    • 2007
  • Asymmetric electro-magnetic force caused by the frictional worn bearing, rotor misalignment and unbalanced rotor etc. generates an asymmetrical operation, vibration and electro-magnetic noise. The need for detection of these rotor eccentricities has pushed the development of monitoring methods with increasing sensitivity and noise immunity. This paper is proposed the analysis method of the squirrel-cage induction motor driven by IGBT inverter using finite element method (FEM) and subroutine. The effect of the unbalanced magnetic pull in the inverter-fed induction motor which is in asymmetrical whirling motion is presented. The analysis results of rotor eccentricity could compare with motors which have been made normal air-gap motor and irregular air-gap motor and verify reliability. The simulation and experiment results can be useful for on-line faults detection monitoring system of induction motors.

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전자기장 해석을 이용한 유도가열 해석 (Analysis of induction heating using analysis of electro-magnetic field)

  • 윤진오;양영수;조시훈;현충민
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2006년도 춘계 학술대회 개요집
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    • pp.187-189
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    • 2006
  • Transient finite element method for analysis of moving coil needs many number of elements and much time to make calculation. Therefore, induction heating process for moving coil was simulated by traveling the position of the heating planes in this paper. In the magnetic and thermal analyses, temperature-dependent magnetic and thermal material properties were considered. Finite element program was developed and finite element results were compared with the experimental results.

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