• 제목, 요약, 키워드: electromagnetic force

검색결과 618건 처리시간 0.048초

전자계-기계계 결합해석에 의한 건식변압기의 단락강도 예측 (Short Circuit Electromagnetic Force Prediction by Coupled Electromagnetic-Mechanical Field Analysis of Dry-Type Transformer)

  • 안현모;한성진
    • 전기학회논문지
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    • v.60 no.2
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    • pp.301-308
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    • 2011
  • This paper deals with the coupled electromagnetic-mechanical field analysis for short-circuit electromagnetic force of the dry-type transformer. The short-circuit currents are calculated using external circuit in accordance with short-circuit test equipment. According to short-circuit current, the generated magnetic leakage flux density in dry-type transformer model is calculated by finite element method. The radially-directed electromagnetic forces in windings are calculated using electromagnetic field analysis and then axially-directed electromagnetic forces in windings are calculated using electromagnetic-mechanical field analysis. The calculated axially-directed electromagnetic forces in high voltage winding are compared to those of measured ones and showed good agreement with experimental results.

Numerical analysis of the electromagnetic force for design optimization of a rectangular direct current electromagnetic pump

  • Lee, Geun Hyeong;Kim, Hee Reyoung
    • Nuclear Engineering and Technology
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    • v.50 no.6
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    • pp.869-876
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    • 2018
  • The force of a direct current (DC) electromagnetic pump used to transport liquid lithium was analyzed to optimize its geometrical and electrical parameters by numerical simulation. In a heavy-ion accelerator, which is being developed in Korea, a liquid lithium film is utilized for its high charge-stripping efficiency for heavy ions of uranium. A DC electromagnetic pump with a flow rate of $6cm^3/s$ and a developed pressure of 1.5 MPa at a temperature of $200^{\circ}C$ was required to circulate the liquid lithium to form liquid lithium films. The current and magnetic flux densities in the flow gap, where a $Sm_2Co_{17}$ permanent magnet was used to generate a magnetic field, were analyzed for the electromagnetic force distribution generated in the pump. The pressure developed by the Lorentz force on the electromagnetic force was calculated by considering the electromotive force and hydraulic pressure drop in the narrow flow channel. The opposite force at the end part due to the magnetic flux density in the opposite direction depended on the pump geometrical parameters such as the pump duct length and width that defines the rectangular channels in the nonhomogeneous distributions of the current and magnetic fields.

실리콘 압저항형 진동 센서를 이용한 Voice-coil형 구동기의 미소 전자력 측정 (The Micro Electromagnetic Force Measurement of Voice-coil Actuator using Semiconductor Piezoresistive Type Vibration Sensor)

  • 권기진;이기찬;박세광
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • v.48 no.2
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    • pp.147-152
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    • 1999
  • Semiconductor piezoresistive type vibration sensor was fabricated by using semiconductor process and micromachining technology. To measure the micro electromagnetic force between coil and magnet, fabricated vibration sensor was used. Toapply micro electromagnetic force produced from the micro exciter, small-sized NdFeB permanent magnet was attached on the mass of the fabricated vibration sensor. The measured electromagnetic force are about 5~180dyne when the applied sinusoidal current of 1KHz in the range of 1.5~8mA. The measurement of micro electromagnetic forcewas performed by changing the distance between coil and magnet. Output characteristics of micro electromagnetic force according to the applied coil current were linear. Furthermore, output results were used to get the transfer constant that is important to decide the efficiency and the performance of the coil and magnet.

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Electromagnetic Forming Process Analysis Based on Coupled Simulations of Electromagnetic Analysis and Structural Analysis

  • Lee, Man Gi;Lee, Seung Hwan;Kim, Sunwoo;Kim, Jin Ho
    • Journal of Magnetics
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    • v.21 no.2
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    • pp.215-221
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    • 2016
  • We conducted a phased electromagnetic forming process analysis (EFPA) over time through a coupling of electromagnetic analysis and structural analysis. The analysis is conducted through a direct linkage between electromagnetic analysis and structural analysis. The analysis process is repeated until the electric current is completely discharged by a formed coil. We calculate the forming force that affects the workpiece using MAXWELL, a commercial electromagnetic finite element analysis program. Then, we simulate plastic behavior by using the calculated forming force data as the forming force input to ANSYS, a commercial structure finite element analysis program. We calculate the forming force data by using the model shape in MAXWELL, a commercial electromagnetic finite element analysis program. We repeat the process until the current is fully discharged by the formed coil. Our results can be used to reduce the error in data transformation with a reduced number of data transformations, because the proposed approach directly links the electromagnetic analysis and the structural analysis after removing the step of the numerical analysis of a graph describing the forming force, unlike the existing electromagnetic forming process. Second, it is possible to simulate a more realistic forming force by keeping a certain distance between nodes using the re-mesh function during the repeated analysis until the current is completely discharged by the formed coil, based on the MAXWELL results. We compare and review the results of the EFPA using the peak value of the forming force that acts on the workpiece (which is the existing analysis method), and the proposed phased EFPA over time approach.

Optimal Design of Electromagnetic Actuator with Divided Coil Excitation to Increase Clamping Force

  • Kim, Tae-Woo;Chang, Jung-Hwan
    • Journal of international Conference on Electrical Machines and Systems
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    • v.3 no.4
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    • pp.446-450
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    • 2014
  • This paper performed the optimal design of electromagnetic linear actuator with divided coil excitation. The table of orthogonal array and response surface methodology (RSM) are applied to maximize the clamping force of the electromagnetic linear actuator with colenoid (COL) and multipolar solenoid (MPS) excitation. The analysis results show that the clamping force of the optimal models with COL and MPS excitation are increased by 41% and 54% at the gap of 0mm compared to the initial models, respectively.

지중 2회선 154 kV 송전케이블의 정상 및 지락고장에 따른 전자기력 분포에 관한 연구 (Study on the Distribution of Electromagnetic Force for 154 kV Power Transmission Cable on Dual Underground Lines by Normal and Earth Fault Current)

  • 김희민;김소영;임상현;박관수
    • KEPCO Journal on Electric Power and Energy
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    • v.1 no.1
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    • pp.21-27
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    • 2015
  • The goal of this study is the size and distribution of the electromagnetic force generated by the current flowing through the second underground line of 154kV power transmission cables by using electromagnetic finite element analysis. So we interpret how mutually electromagnetic force has an effect on the comparable judgement of Trefoil, Duct and Flat, which shows in a numerical arrangement. 154kV OF 1200SQ Cable 1.281km not only is applicable to modeling for underground transmission cable but also examine the effect of line to line, phase to phase and size and direction of the electromagnetic force preparing for the occurrence of normal state and single-phase earth fault, which are arranged in trefoil, duct and flat formation between sections. As showing how the trajectory, and size distribution of the electromagnetic force translate as the arrangement of the cables when a steady-state current and a fault current flows on the underground cables, I hope that when Underground transmission is designed, this data will be useful information.

Design and Analysis of Electromagnetic Tubular Linear Actuator for Higher Performance of Active Accelerate Pedal

  • Lee, Jae-Yong;Kim, Jin-Ho;Lee, Jeh-Won
    • Journal of Magnetics
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    • v.14 no.4
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    • pp.175-180
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    • 2009
  • This paper describes the design and analysis of a tubular linear actuator for intelligent AAP (Active Accelerate Pedal) system. In a driving emergency, the electromagnetic actuator produces an additional pedal force such as the active pedal force and vibration force to release the driver's foot on accelerator pedal. A prior study found that the linear actuator with a ferromagnetic core had a problem in transferring the additional force naturally to a driver due to the cogging force. To reduce the cogging force and obtain higher performance of the AAP system, a coreless tubular linear actuator is suggested. Electromagnetic finite element analysis is executed to analyze and design the coreless tubular actuator, and dynamic analysis is performed to characterize the dynamic performance of the AAP system with the suggested tubular actuator for two types of thrust force.

송전케이블 삼상단락 실증시험을 통한 전자력 대책방안 연구 (The Study on Countermeasures of Electromagnetic Force by Three Phase Short-Circuit Test of Underground Transmission Cable)

  • 강지원;박흥석;윤종건;김양상;홍동석;장우석
    • 전기학회논문지
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    • v.58 no.12
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    • pp.2342-2348
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    • 2009
  • Even though underground transmission cable is an essential transmission method to supply stable power for downtown and population center, the interaction of electromagnetic force by fault current is very large comparing to overhead transmission line due to restricted installation space such as tunnel, and close consideration is required for it. This paper presents countermeasures to reduce and release the effect of electromagnetic force with rope binding and installation of spacer and describes its efficacy through three phase short-circuit test, which will be utilized as basic materials for improvement and development of cleat, hanger, etc. to reduce and release effect of electromagnetic force in the future.

전자기력을 이용한 알루미늄 스크랩 중의 Fe 제거에 관한 연구;Part 2. Al-Si-Cu계 합금 스크랩에서 전자기력에 따른 Fe계 금속간화합물의 이동양상 (A Study on the Elimination of Fe Elements in Aluminum Alloy by Electromagnetic Force;Part 2. The Movement of Fe-Contained Intermetallics with Electromagnetic Force in Al-Si-Cu Scrap)

  • 김정호;노정훈;박준표;윤의박
    • 한국주조공학회지
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    • v.18 no.3
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    • pp.240-245
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    • 1998
  • In the view point of the environmental conservation and the energy reduction, the recycling of metal scrap is coming as one of the global subjects in the world. In this study, the movement of intermetallics with electromagnetic force in a melt of a scrap of Al-Si-Cu alloy (JIS ADC12), which was widely used in diecasting process, was investigated in order to eliminate the Fe element, which was usually accumulated in a scrap. In this study, we applied electromagnetic method to eliminate Fe element in ADC12 aluminum alloy scrap which contains 1.64wt.% Fe and the effects of electromagnetic force on the particle movement was visualized and confirmed by water modeling and experiment. As a result, the Fe intermetallic compounds are moved to the direction opposite to that of the electromagnetic force as the force applies, thus eliminated from the bulk metal. Therefore, the content of Fe in matrix decreased from 1.64wt.% to 0.45wt.%.

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케이블 삼상단락 실증시험을 통한 전자력 영향 검토 (The Study of Electromagnetic Force by Three Phase Short-Circuit Test of Cable)

  • 홍동석;김해준;박성민;장우석;박흥석;장태인;강지원
    • 대한전기학회:학술대회논문집
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    • pp.395_396
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    • 2009
  • This paper handles with effect of electromagnetic force on the cables by fault current accompanied by accident of underground transmission cable. Even though underground transmission cable is an essential transmission method to supply stable power for downtown and population center, interaction of electromagnetic force from fault current is very large comparing to overhead transmission line due to restricted installation space such as tunnel, etc. and close consideration is required for it. This paper describes the effect of electromagnetic force through results of three phase short-circuit test and electromagnetic force analysis using theoretical calculations and electrical evaluation test after three phase short-circuit test, which will be utilized as basic materials for improvement and development of cleat, hanger, etc. to reduce and release effect of electromagnetic force in the future.

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