• Title/Summary/Keyword: Outer-rotor

Search Result 176, Processing Time 0.031 seconds

Rotordynamic Influences of a Tie Shaft in a APU Gas Turbine Rotor-Bearng System (보조동력 개스터빈 로터-베어링 시스템에서 체결축의 로터다이나믹 영향)

  • Lee, An-Sung;Lee, Young-Seob
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2000.06a
    • /
    • pp.1051-1057
    • /
    • 2000
  • A projected 100 kW APU gas turbine rotor-bearing system has a main outer shaft, which is composed of some numbers of segmented sections for manufacturing and assembly conveniences. For a secure assembly of the segmented sections a tie shaft or inner shaft is installed inside of the outer shaft and a tensional axial preload of 50,000 N is provided to it. In this paper it is intended to set-up a sound modeling method of the APU rotor system, and particularly, the influences of the tie shaft on the rotordynamic characteristics of the entire APU gas turbine rotor-bearing system are investigated. Analysis results show that as a conservative design practice the inner tie shaft should be actively modeled in the rotordynamic analysis of the APU rotor-bearing system, and its effects on the dynamic behaviors of the outer shaft should be thoroughly design-reviewed.

  • PDF

A Study on the Design Procedure of the Eight Pole Magnetic Bearings for the Inner-rotor and the Outer-rotor Type

  • Lee, Jun-Ho;Park, Chan-Bae;Lee, Byung-Song;Lee, Su-Gil;Kim, Jae-Hee;Jung, Shin-Myung;Lee, Hyung-Woo
    • Journal of Electrical Engineering and Technology
    • /
    • v.8 no.6
    • /
    • pp.1424-1430
    • /
    • 2013
  • This paper presents design procedure of the magnetic bearings used for high-speed electric machines and flywheel energy storage systems. Magnetic bearing can be categorized by inner-rotor type and outer-rotor type according to the position of the rotary disc. These two types are applicable based on application environments such as application space, required attraction force, and controllability. Magnetic bearing is generally designed based on the ratio (geometrical coefficient or geometrical efficiency) of pole width to rotor journal radius but proper ratio is only decided by the analysis. This is the difficulty of the magnetic bearing design. In this paper, proper design technology of the inner-rotor type and outer-rotor-type eight pole magnetic bearings is introduced and compared with the FEM analysis results, which verifies the proposed design procedure is suitable to be applied to the design of the magnetic bearings for the industrial applications and flywheel energy storage system.

Design and Analysis of Gerotor with Generalized Shapes for Power-Steering Units (파워 스티어링 유닛용 일반형상 제로터의 설계 및 해석)

  • Jeong, Jae-Tack;Shin, Soo-Sik;Kim, Kap-Tae
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.34 no.7
    • /
    • pp.891-896
    • /
    • 2010
  • A gerotor is used in power-steering units (PSUs) as well as in hydraulic motors or pumps. The inner rotor is developed on the basis of the shape of the outer rotor tooth, which normally has one arc. The method of generating inner rotor on the basis of a generalized shape of outer rotor is analyzed with a view to improve PSU characteristics. An arc-shaped outer rotor with two curvatures was used in the analysis; design parameters such as the shape and curvature of the inner rotor, the flow rate of the gerotor, the position of contact point, and slip velocity are calculated, and these results are shown. This analysis enables us to develop a new design of compact PSUs.

A Study on the Reduction of Cogging Torque of Outer-Rotor Type BLDC Motor for Washing Machines (세탁기용 외전형 BLDC 전동기의 코깅 토오크 저감에 관한 연구)

  • Kim Jae-Min;Chang Cheul-Hyeok;Chung Tae-Kyung
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.54 no.5
    • /
    • pp.222-230
    • /
    • 2005
  • This paper deals with the reduction of cogging torque of a outer-rotor type BLDC motor mainly used for washing machines. The motor comprises permanent magnet outer-rotor and stator with coils and core. This structure inherently produces vibration and cogging torque because of uneven reluctance according to rotation of the rotor. Up to now, adopted a type of 24 magnet pole and 36 slot-stator. This generates high main torque but accompanies comparatively large cogging torque. This paper proposes a 32-pole 36-slot type motor which reduces cogging torque remarkably. The influence of cogging torque is varied according to pole-slot combinations. The characteristic of the motor was obtained by a two-dimensional finite element method coupled with a drive circuit. The performance of the proposed model is superior to that of the existing model because of the reduction of torque ripple and the improvement of back ernf wave form.

Development of Outer-Rotor Type In-Wheel BLDCM for Three-Wheeled Electric Vehicle (삼륜 전기 자동차용 외전형 In-Wheel BLDCM의 개발)

  • Jeong, Kwang-Il;Ahn, Jin-Woo
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.61 no.4
    • /
    • pp.567-573
    • /
    • 2012
  • Outer rotor type in-wheel Blushless DC Motor(BLDCM) for three-wheeled electric vehicle is researched. In-wheel system is to drive the electric vehicle without mechanical transmission, shaft, differential gears or other mechanical system. The motor is designed considering the performance requirements and drive modes of the vehicle. The determined dimensions as well as the slot and rotor pole are simulated by magnetic and thermal finite element analysis and ansys workbench to analyze the performance and heating of the motor. In order to verify the performance characteristics of the proposed motor, the experiment tests are executed and satisfy well the requirements.

Optimal Design of an Outer-rotor Flux-switching Permanent Magnet Motor for High Speed Operation (외전형 FSPM(Flux Switching Permanent Magnet) 전동기의 고속 운전을 위한 최적 설계)

  • Lee, Jae-Kwang;Jang, Jin-Seok;Kim, Byung-Teak
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.11
    • /
    • pp.2035-2042
    • /
    • 2011
  • In this paper, we proposed the outer-rotor type of FSPM motor for high speed operation and optimized motor shape. First of all, combinations of pole and slot numbers are examined for the optimal back-EMF and cogging torque, then optimizes the better shape design of the permanent magnet, rotor pole width. Further, The winding turns are obtained by circle of the voltage limit equation and motor parameters to minimize the current and to improve the efficiency. As a result, the performance of the designed model is satisfied, and it is verified through a two-dimensional finite element method (2D-FEA).

Design and Characteristics Analysis of Outer Rotor Type BLDC Motor (Outer Rotor 방식 BLDC 전동기 설계 및 특성 해석 모델링)

  • Park, Young-Il;Youn, Sun-Ky;Cho, Yun-Hyun;Jang, Woo-Kyo;Lee, Jae-Ho;Shin, Dong-Sik
    • Proceedings of the KIEE Conference
    • /
    • 1999.07a
    • /
    • pp.391-393
    • /
    • 1999
  • This paper is proposed the design method of Outer Rotor BLDC by the magnetic equivalent method. In order to compute and estimate the performance parameter of Outer type BLDC. The dynamic model and characteristics analysis of BLDC is obtained by Matlab.

  • PDF

Analysis of High Torque and Power Densities Outer-Rotor PMFSM with DC Excitation Coil for In-Wheel Direct Drive

  • Ahmad, M.Z.;Sulaiman, E.;Kosaka, T.
    • Journal of Magnetics
    • /
    • v.20 no.3
    • /
    • pp.265-272
    • /
    • 2015
  • In recent years, flux switching machines (FSMs) have been an attractive research topic owing to their tremendous advantages of robust rotor structure, high torque, and high power capability suitable for intensive applications. However, most of the investigations are focusing on the inner-rotor structure, which is incongruous for direct drive applications. In this study, high torque and power densities of a new 12S-14P outer-rotor permanent magnet (PM) FSM with a DC excitation coil was investigated based on two-dimensional finite element analysis for in-wheel direct drive electric vehicle (EV). Based on some design restrictions and specifications, design refinements were conducted on the original design machine by using the deterministic optimization approach. With only 1.0 kg PM, the final design machine achieved the maximum torque and power densities of 12.4 Nm/kg and 5.93 kW/kg, respectively, slightly better than the inner-rotor HEFSM and interior PM synchronous machine design for EV.

A Study on Various Rotor Shape of Outer Rotor Permanent Magnet Synchronous Machine for High Torque Density (고 토크밀도를 위한 다양한 회전자 형상의 외전형 영구자석 동기전동기에 관한 연구)

  • Cha, Jin-wook;Kwon, Byung-il
    • Proceedings of the KIEE Conference
    • /
    • 2015.07a
    • /
    • pp.732-733
    • /
    • 2015
  • 본 논문에서는 외전형 영구자석 동기전동기(Outer rotor Permanent Magnet Synchronous Motor)의 회전자 형상에 따른 토크특성을 비교하였다. 표면부착형 영구자석(SPM) 형태의 FAN용 PMSM을 설계하고 이 모델을 기준으로 동일한 외경사이즈를 갖지만 더 높은 토크 밀도를 갖는 4가지 매입형 영구자석(IPM) 형태의 PMSM을 제시한다. Finite Element Analysis(FEM)을 통하여 각 모델의 특성을 해석하고 자석 사용량과 토크를 비교 및 분석하였다.

  • PDF