• 제목/요약/키워드: eddy-current loss

검색결과 218건 처리시간 0.026초

Numerical Investigation on Permanent-Magnet Eddy Current Loss and Harmonic Iron Loss for PM Skewed IPMSM

  • Lim, Jin-Woo;Kim, Yong-Jae;Jung, Sang-Yong
    • Journal of Magnetics
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    • 제16권4호
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    • pp.417-422
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    • 2011
  • This paper presents the characteristics of PM eddy current loss and harmonic iron loss for PM step-skewed Interior Permanent Magnet Synchronous Motor (IPMSM) with concentrated windings and multi-layered PM under the running condition of maximum torque per ampere (MTPA) and flux-weakening control. In particular, PM eddy current loss and harmonic iron loss in IPMSM have been numerically computed with three-dimensional Finite Element Analysis (3D FEA), whereby IPMSM with concentrated windings and multi-layered PM has been designed to identify the optimized skew angle contributing to the reduced PM eddy current loss and torque ripples, while maintaining the required average torque. Furthermore, numerical investigation on PM eddy current loss and iron loss at MTPA and flux-weakening control has been carried-out in terms of PM step-skew.

Improved Design to reduce Eddy Current Loss in Retain Ring in Superconducting Machines

  • Lee, Sang-Ho;Jung, Jae-Woo;Sun, Tao;Hong, Jung-Pyo;Kim, Yeong-Chun
    • 한국초전도ㆍ저온공학회논문지
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    • 제13권2호
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    • pp.13-16
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    • 2011
  • This paper describes the reduction method of eddy current loss generated into a retaining ring installed in wound-field superconducting machine. In order to suggest the reduction method of eddy current loss of the retaining ring, this paper is divided into three parts. Firstly, eddy current loss of prototype model is calculated. Secondly, eddy current loss versus material and shape of the retaining ring is compared. Finally, the material and the shape of the retaining ring to reduce coupling loss generated by a time-varying magnetic field are proposed. In this paper, eddy current loss is calculated by 3-dimensional transient analysis.

마그네틱 기어의 영구자석 부착방법에 따른 영구자석 와전류손실 분석 (Analysis of Permanent Magnet Eddy Current Loss by Permanent Magnet Attaching Method of Magnetic Gears)

  • 박의종;김성진;정상용;김용재
    • 전기학회논문지
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    • 제66권6호
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    • pp.911-915
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    • 2017
  • Recently, there has been an increasing interest in the non-contact power transmission method of magnetic gears. Since there is no mechanical contact, noise caused by friction can be reduced, and even if a sudden large force is applied, the impact of the gear is close to zero. Further, since the power is transmitted by the magnetic flux, it has high reliability. However, there is a problem that a loss due to a magnetic field due to use of a magnetic flux. The loss caused by the magnetic field of the magnetic gear is a joule loss called eddy current loss. In addition, the eddy current loss in the magnetic gear largely occurs in the permanent magnet, but it is a fatal loss to the permanent magnet which is vulnerable to heat. Particularly, magnetic gears requiring high torque density use NdFeB series permanent magnets, and this permanent magnets have a characteristic in which the magnetic force decreases as temperature increases. Therefore, in this paper, the eddy current loss of the permanent magnet according to the permanent magnet attaching method is analyzed in order to reduce the eddy current loss of the permanent magnet. We have proposed a structure that can reduce the eddy current loss through the analysis and show the effect of reducing the loss of the proposed structure.

공간고조파법을 이용한 반경방향 영구자석을 갖는 자기커플링의 와전류 손실 해석 (Eddy Current Loss Analysis in Radial Flux Type Synchronous Permanent Magnet Coupling using Space Harmonic Methods)

  • 민경철;강한빛;박민규;조한욱;최장영
    • 전기학회논문지
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    • 제63권10호
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    • pp.1377-1383
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    • 2014
  • This paper deals with eddy current loss of magnetic coupling with radial permanent magnet (PM) using analytical method such as a space harmonic method. Superposition of two kinds analysis model is used to analyze eddy current loss induced in inner PM and outer PM of magnetic coupling. When the eddy current is induced, the environmental temperature increases, and the permanent magnet(PM) characteristics are degraded because the performance of PM is greatly influenced by temperature rise. Hence, the calculation of eddy current loss becomes an important factor in the magnetic coupling. In order to analyze eddy current loss, first, on the basis of the magnetic vector potential and two-dimensional(2-D) polar-coordinate system, the magnetic field solutions of the radial magnetized PM are obtained. And we obtain the analytical solutions for the eddy current density produced by permanent magnet. Lastly, analytical solutions for eddy current loss are derived by using equivalent, electrical resistance calculated from magnet volume and analytical solution for eddy current density. This analytical results are validated by comparing with the 2-D finite element analysis (FEA).

154 kV 3상 전력 케이블의 상호작용에 따른 금속 Sheath에서 발생하는 와전류 손실 분석 (Analysis of Eddy Current Loss Considering Interaction Effect in Metal Sheath of 154 kV Three Phase Power Cable)

  • 임상현;김기병;박관수
    • KEPCO Journal on Electric Power and Energy
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    • 제6권4호
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    • pp.389-392
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    • 2020
  • 전력 케이블에서 발생하는 손실을 정확히 예측하기 위해서는 금속 시스에서 발생하는 와전류 손실에 대한 분석이 필요하다. 동손의 경우 도체의 저항과 전류에 의하여 쉽게 계산이 되지만 금속 시스에서 발생하는 와전류의 경우 측정 및 예측이 어렵기 때문이다. 이를 위하여 선행연구에서는 단상 케이블에서 발생하는 와전류 손실을 분석하였지만 실제 환경에서는 3상이 대부분 사용되기 때문에 적용하기에는 한계가 존재한다. 그러므로 본 논문에서는 3상 케이블의 금속 시스에서 발생하는 와전류 손실에 대하여 발생 원인에 따라 이론적으로 분석하고 전자기 수치 해석을 통하여 삼각 배열과 수평배열에서 발생하는 와전류 손실을 예측하였다.

Novel Claw Pole Eddy Current Load for Testing DC Counter Rotating Motor - Part II: Design and Modeling

  • Kanzi, Khalil;Roozbehani, Sam;Dehafarin, Abolfazl;Kanzi, Majid
    • Journal of international Conference on Electrical Machines and Systems
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    • 제1권4호
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    • pp.412-418
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    • 2012
  • Eddy current brakes are electromechanical devices used as variable mechanical loads for testing electrical machines. Accurate modeling of eddy current loss is an important t factor for optimum design of eddy brake systems. In this second part, we propose novel formulations of eddy current loss in novel claw-pole eddy brake system. The proposed model for eddy current loss in novel claw-pole eddy brake system depends on the size of the claw poles. Also, in this paper, the flux density is measured by using the magnetic circuit of the novel claw pole. The model results are compared with experimental results and they are found to be in good agreement.

해석적 방법을 이용한 표면부착형 영구자석 기기의 회전자 와전류 손실해석 (Eddy-Current Loss Analysis in Rotor of Surface-Mounted Permanent Magnet Machines Using Analytical Method)

  • 최장영;최지환;장석명;조한욱;이성호
    • 전기학회논문지
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    • 제61권8호
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    • pp.1115-1122
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    • 2012
  • This paper analyzes eddy-current loss induced in magnets of surface-mounted permanent magnet (SPM) machines by using an analytical method such as a space harmonic method. First, on the basis of a two-dimensional (2D) polar coordinate system and a magnetic vector potential, the analytical solutions for the flux density produced by armature winding current are obtained. By using derived field solutions, the analytical solutions for eddy current density distribution are also obtained. Finally, analytical solutions for eddy current loss induced in rotor magnets are derived by using equivalent electrical resistance calculated from magnet volume and analytical solutions for eddy-current density distribution. In particular, the influence of time harmonics in armature current on the eddy current loss is fully investigated and discussed. All analytical results are validated extensively by finite element analysis (FEA).

고주파 Mn-Zn ferrites 전력손실에 대한 고찰 (Study on the Power Loss of High Frequency Mn-Zn ferrites)

  • 서정주
    • 자원리싸이클링
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    • 제11권5호
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    • pp.34-38
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    • 2002
  • 최근 전자기기의 경박단소화로 페라이트 코아의 사용주파수가 고주파화 되고 있다. Mn-Zn ferrites에서 전력손실은 hysteresis loss, eddy current loss, residual loss로 구성되어 있으며, 500 KHz 이상의 주파수 영역에서는 residual loss가 주도적인 손실을 나타낸다. Induction level이 50 mT 이하인 경우 전력손실은 주파수의 3승 이상에 비례하여 증가한다. 작은 grain과 치밀한 미세구조는 고주파 대역에서 eddy current loss를 감소시킬 뿐만 아니라 자속밀도를 증가시켜 Residual loss역시 억제한다. Resonance frequency와 static permeability를 곱한 값이 큰 시편일수록 고주파 영역에서 낮은 전력손실을 보인다.

PWM 인버터의 스위칭 주파수에 따른 브러시레스 DC 모터에서의 와전류 손실 특성 해석 (Analysis of Eddy Current Loss in Brushless DC Motor according to the Swiching Frequency of the PWM Inverter)

  • 김와성;최태식;김윤현;이주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 B
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    • pp.675-677
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    • 2000
  • In the paper the eddy current loss in brushless DC motor due to switching frequency supplied by PWM inverter, is analyzed. The compensated conductivity is used in order to analyze the eddy current loss in brushless DC motor which has lamination structure. The eddy current loss is deceased when switching frequency supplied by PWM inverter is gradually increased from 1.2kHz up to 12kHz. The high switching frequency of PWM inverter make the output wave into a similar sine wave and this leads to the decreasing eddy current loss.

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해석적 방법을 이용한 슬롯리스 양측식 코어드 타입 영구자석 발전기의 와전류 손실 해석 (Eddy Current Loss Analysis of Slotless Double-sided Cored Type Permanent Magnet Generator by using Analytical Method)

  • 장강현;정경훈;홍기용;김경환;최장영
    • 전기학회논문지
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    • 제65권10호
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    • pp.1639-1647
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    • 2016
  • This paper deals with eddy current loss analysis of Slotless Double sided Cored type permanent magnet linear generator by using analytical method, space harmonic method. In order to calculate eddy current, this paper derives analytical solution by the Maxwell equation, magnetic vector potential, Faraday's law and a two-dimensional(2-D) cartesian coordinate system. First, we derived the armature reaction field distribution produced by armature wingding current. Second, by using derived armature reaction field solution, the analytical solution for eddy current density distribution are also obtained. Finally, the analytical solution for eddy current loss induced in permanent magnets(PMs) are derived by using equivalent, electrical resistance calculated from PMs volume and eddy current density distribution solution. The analytical result from space harmonic method are validated extensively by comparing with finite element method(FEM).