• Title/Summary/Keyword: Eddy Current

Search Result 1,084, Processing Time 0.026 seconds

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

  • Choi, Jang-Young;Choi, Ji-Hwan;Jang, Seok-Myeong;Cho, Han-Wook;Lee, Sung-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.61 no.8
    • /
    • pp.1115-1122
    • /
    • 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).

Permanent Magnet Eddy Current Analysis of SPM Synchronous Motors according to Magnet Shapes

  • Lee, Sun-Kwon;Kang, Gyu-Hong;Kim, Byoung-Woo;Hur, Jin
    • Journal of international Conference on Electrical Machines and Systems
    • /
    • v.3 no.4
    • /
    • pp.398-402
    • /
    • 2014
  • This paper presents the comparison study of permanent magnet (PM) eddy current of concentrated winding type surface permanent magnet synchronous motor (SPMSM) with different rare-earth magnet shapes. The fractional slot winding having 10 poles and 12 slots is studied. The PM eddy current is analyzed to compare for each shape by 2 dimensional (2D) finite element analysis (FEA). The eddy current and their loss of particular position of PM as well as their distributions are displayed for each model. The effect of partly enlarged air-gap made by PM shape to PM eddy current is compared.

The Influence of Magnetization Pattern on the Performance of Permanent Magnet Eddy Current Couplings and Brakes

  • Cha, Hyun-Rok;Cho, Han-Wook;Lee, Sung-Ho
    • Journal of Electrical Engineering and Technology
    • /
    • v.3 no.3
    • /
    • pp.379-384
    • /
    • 2008
  • This paper examines permanent magnet eddy current couplings and brakes. Specifically, the effect of permanent magnet magnetization patterns on the magnetic field and force production is investigated. The eddy current couplings and brakes employ high energy-product neodymium-iron-boron (NdFeB) permanent magnets that act on iron-backed copper drums to provide torque transfer from motor to load without mechanical contact. A 2-dimensional finite element modeling is performed to predict the electromagnetic behavior and the torque-speed characteristics of permanent magnet type eddy current couplings and brakes under constant speed operation.

Novel Electromagnetic Induction Eddy Current DPH based Continuous Pipeline Fluid Heating using Soft Switching PWM High Frequency Inverter

  • Nam, Jing-Rak
    • Journal of information and communication convergence engineering
    • /
    • v.6 no.3
    • /
    • pp.305-309
    • /
    • 2008
  • This paper presents an innovative prototype of a new conceptual electromagnetic induction eddy current based fluid heating appliance using voltage-fed quasi resonant zero voltage soft switching PWM high-frequency inverter using IGBTs, which can operate at a constant frequency variable power regulation scheme. The promising simple high efficient low noise inverter type electromagnetic induction eddy current based pipeline fluid heating appliance is proposed for saturated steam generator, superheated steam generator, hot water and hot air producer, metal catalyst heating for exhaust gas cleaning in engine. Under these technological backgrounds, a novel electromagnetic induction eddy current Dual Packs Heater(DPH) based pipeline fluid heating incorporates thin metal layer type package for continuous fluid heating appliances applying two types of voltage-fed quasi load resonant ZVS-PWM high frequency inverter. The unique features of a novel electromagnetic induction eddy current DPH based continuous pipeline fluid heating appliance is illustrated on the basis of simulation and discussed for the steady state operating characteristics and experimental results.

Performance Measurement of the Eddy Current Heat Generator with Different Array of Permanent Magnets (서로 다른 자석 배열을 가지는 와전류 열원화 장치의 성능 측정)

  • Yun, Teak-Han;Son, Young-Woo;Lee, Jang-Ho
    • New & Renewable Energy
    • /
    • v.9 no.1
    • /
    • pp.17-24
    • /
    • 2013
  • Eddy Current is one of ways to make heat using rotational energy of wind turbine rotor. Four difference arrays of permanent magnets around rotor surface are used to generate heat using eddy current in this study. For the evaluation of heating performance, new test rig is prepared to measure water flow and temperatures in the inlet and outlet of the eddy current heat generator. In the test, torque and rotational speed are also measured in the motor driven system, and evaluated if the torque is matched with it of wind turbine rotor or not. It will be shown that the eddy current heat generator can be applied to real urban wind energy systems in this study.

Eddy Current Signal Analysis for Transmit-Receive Pancake Coil on ECT Array Probe

  • Lee, Hyang-Beom
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.26 no.1
    • /
    • pp.25-29
    • /
    • 2006
  • In this paper, the eddy current signals come from a pair oi transmit-receive (T/R) pancake coil on ECT array Probe are analyzed with the variations of the lift-of and of the distance between transmit and receive coils. To obtain the electromagnetic characteristics of the probes, the governing equation describing the eddy current problems is derived from Maxwell's equation and is solved using three-dimensional finite element method. Eddy current signals from T/R coils on ECT array probe have quite different characteristics compared with ones from impedance coil on rotating pancake coil probe. The results in this paper ran be helpful when the field eddy current signals from ECT array probe are evaluated.

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
    • /
    • v.16 no.4
    • /
    • pp.417-422
    • /
    • 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.

A Study on the Dynamic Behavior of Eddy Current Braking System for Korean High Speed Train (고속전철의 와전류 제동장치 동적 거동특성 연구)

  • 박찬경;최강윤;현승호;곽수태
    • Proceedings of the KSR Conference
    • /
    • 2001.05a
    • /
    • pp.147-154
    • /
    • 2001
  • Dynamic behavior of high speed train is very important because the high speed train should be safe and satisfied with the ride comfort. An eddy current brake system is mounted on trailer bogie and wheelset. The eddy current braking force longitudinally exerts on the articulated trailer bogie and the attraction force vertically exerts on the wheelset. Because a frame of eddy current brake system is flexible, these forces generate the vertical vibration at middle point of the frame. Also, the vibration change the vertical clearance between an electromagnet and top of rail which affect the magnitude of braking and attracting forces. Therefore, the dynamic behavior of the eddy current braking system must be predicted for design the dynamic characteristic of its mounting system when normally operate on rail which have irregularity. Vampire program is used for Prediction of the dynamic behavior of an eddy current braking system.

  • PDF

2-D Finite Element Analysis of Brushless DC Motor Considering Eddy Current (와전류 손실을 고려한 브러시리스 DC 모터의 2차원 유한 요소 해석)

  • Choi, Tae-Sik;Chun, Yon-Do;Lee, Ju;Lim, Tae-Bin;Kim, Suk-Tae
    • Proceedings of the KIEE Conference
    • /
    • 1999.07a
    • /
    • pp.49-51
    • /
    • 1999
  • This paper presents an efficient 2D finite element analysis(FEA) for brushless DC motor (BLDCM) taking into account the eddy current and lamination effect of stator. In BLDCM, the dynamic characteristic analysis considering the eddy current and driving circuit is applied for the accurate prediction of motor performance in high speed because the eddy current loss is proportional of square of the driving frequency. According to the variation of lamination number, the characteristics of electro magnetic force, torque, and eddy current loss are analyzed. From the results, it is known that the effect of the lamination of stator on the eddy current loss is verified.

  • PDF

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
    • Progress in Superconductivity and Cryogenics
    • /
    • v.13 no.2
    • /
    • pp.13-16
    • /
    • 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.