• Title/Summary/Keyword: Motor assessment

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Rotational loss assessment of flywheel energy storage system by Motor/Generator core (전동/발전기 코어에 의한 초전도 플라이휠 에너지 저장장치의 회전손실 특성 평가)

  • Lee, Jeong-Phil;Han, Young-Hee;Jung, Se-Yong;Han, Sang-Chul;Jeong, Nyeon-Ho;Sung, Tae-Hyun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.10
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    • pp.1775-1781
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    • 2007
  • In this paper, the rotational loss of the superconductor flywheel energy storage system (SFES) by motor/generator stator core was assessed. To do this, the vertical axial type SFES with journal type superconductor bearing was manufactured. To quantitatively assess the rotational loss by the stator core, the rotational losses by superconductor bearing and the degree of a vacuum were measured. In case of variation of the inner radius and outer radius of the stator core, the rotational losses were measured. From the experimental results, It is confirmed that the rotational loss can be reduced by means of the optimal stator core design.

Partial Discharge Tests for Traction Motor Using 1000 pF Couplers (1000 pF 커플러를 이용한 견인전동기 부분방전특성)

  • Ko, Byeong-Hun;Park, Hyun-June;Kwon, Sam-Young;Na, Hae-Kyung;Lee, Hyung-Woo
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.214-218
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    • 2007
  • With the development of high speed railway, traction motors play a critical role in the operation of railway vehicle. This paper describes the use of 1000 pF coupler as a on-line partial discharge (PD) measurement for the assessment of railway traction motor. The PD tests are performed with developed PD analyzer and the 5 model coils such as thermal, electrical, mechanical and environmental aging respectively at various AC voltages. On-line PD tests using 1000 pF couplers show that PD patterns can be detected successfully at 2.3 kV.

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Induction Motor of Effect for Variation Sag, Swell of Harmonic Order (유도전동기 운전 중 Sag 영향에 의한 고조파 차수 변화)

  • Park, In-Deok;Lee, Seung-Hwan;Kim, Si-Kyung
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.954-955
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    • 2008
  • In this paper, the voltage harmonics are investigated in terms of the voltage sag versus the time constants of electric machinery under the source voltage variation condition. The electric machinery and compensation equipment are established on the proposed design scheme based on voltage quality effect assessment technology. It have been analyzed how the variation of harmonic order, the output current, the DC-Link voltage and the induction motor speed is carried out under the voltage sag and switching frequency variation.

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Electrophysiologic Examination and Physiotherapy for Facial Nerve Palsy (안면신경 마비의 전기생리학적 검사 및 물리치료)

  • Ryoo, Jae-Kwan;Kim, Jong-Soon
    • Journal of Korean Physical Therapy Science
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    • v.4 no.3
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    • pp.499-509
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    • 1997
  • The facial nerve have a long pathway. Thus facial nerve fibers easily involved at any point along their course will lead to a facial palsy of lower motor neuron type and upper motor neuron type. The electrophysiologic examination can evaluate and anticipating that prognosis of facial nerve palsy. The electrophysiologic examination are Nerve Excitability Test(NET), Elecctroneurography(ENG), Electro-myography(EMG), Blink Reflex, and Electrogustometry et.al. The NET is very useful method for assessment of prognosis and distinguish between nerve degeneration and physiological block as early as 72 hour after onset of the facial palsy. And other examination also give objectively information of facial nerve for prognosis and treatment. Treatment goal of physiotherapy are prevent contracture and disuse atrophy of facial muscle with muscle reeducation and strengthening and maintain symmetry facial motion. The treatment better start as early as possible.

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Assessment of Insulation Condition in High Voltage Motor Stator Windings (고압전동기 고정자 권선의 절연상태 평가)

  • Kim, Hee-Dong;Park, Eui-Gab;Park, Wan-Jo
    • Proceedings of the KIEE Conference
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    • 1999.07e
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    • pp.2392-2395
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    • 1999
  • This paper describes to access the insulation deterioration condition of the stator windings in six high voltage motors. Nondestructive tests have been carried out on stand-still motors. These tests include ac current increase rate($\Delta$I), delta tan delta(${\Delta}tan{\delta}$), and maximum partial discharge(PD). AC current and $tan{\delta}$ were measured by Schering bridge. The measurement of PD patterns were conducted using digital partial discharge detector. PD patterns were observed treeing and internal discharges in Motor 1 and 2. The stator windings of two motors were found to be in a poor condition and their were recommended to rewind. The stator. windings of four motors were judged to be in serviceable condition.

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Standardization of the Korean Child Development Inventory (K-CDI 아동발달검사 표준화 연구)

  • Kim, Jeong-Mee;Shin, Hee-Sun
    • Korean Journal of Child Studies
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    • v.27 no.4
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    • pp.39-53
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    • 2006
  • The Korean version of the Child Development Inventory (K-CDI) is a developmental screening test for children functioning in the one-six year range. Based on parent-report, the inventory assesses child developmental functioning in the areas of social, self-help, gross motor, fine motor, expressive language, language comprehension, letter and number skills, general development, and various symptoms and behavior problems. Participants were recruited from childcare centers and private groups and finally 1,143 children and their mothers from 4 locations nationwide participated in this study. Through analysis of item response rate of 270 items in 9 areas, new norm was formed. Reliability determined by internal consistency were relatively high (Cronbach ${\alpha}=.95$). Intercorrelations among sub-scales (range: .49-.96) indicated the construct validity, and the correlation between K-CDI and other screening tests supported the concurrent validity.

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Improvement of Armature shape of multi-winding type LDM (다권선 리니어 직류 전동기의 전기자 형상 개선에 관한 연구)

  • Lee, S.M.;Baek, S.H.;Maeng, I.J.;Woo, Y.S.;Kim, I.N.
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.766-768
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    • 2000
  • In this paper, we present the optial design and analysis of a novel brushless do linear motor, which can operate as a selfless linear stepping motor, with two armature cores and two back iron and five high energy product magnets. We used Maxwell program package for computing the flux distribution and static force. The assessment of the analytical and measured values shows a very goof correlation among them. The result are presented in this paper.

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A Study on the Relationship between Sound Quality and Structural Mechanics in Automobiles (차량 구조 강성과 소음 음질간의 상관도 연구)

  • Choi Jongdae;Kim Sangmin
    • Proceedings of the Acoustical Society of Korea Conference
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    • autumn
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    • pp.239-242
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    • 2000
  • In the present study, the influence of car body structures to the noise and vibration characteristics has been sought. The numerical modal analysis for the body-in-white is employed to predict the vibratory response of structure, and then followed by the experimental modal testing to confirm the validity of the model. Using the results of numerical simulations with the designated modal parameters, the optimal structural configuration has been deduced. Special interests have been paid to the sensitivity of sound quality to the structural integrity. Since the structural integrity has a close relationship to the structure-born noise, the substantially low frequency range, which is far below the frequency range almost barely sensible by human auditory organ but still quite influential to overall impression, is especially examined. The subjective assessment agrees with the objective evaluation by means of traditional sound measures as well as psychoacoustic metrics.

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The environmental policy suggestion for Electric Motor Unit through Environmental Product Declaration (전동차 내장판넬의 환경성 정보 공개 및 정책 활용 방안)

  • Chun, Yoon-Young;Jeong, In-Tae;Lee, Kun-Mo;Kim, Yong-Ki
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.1536-1544
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    • 2006
  • The aim of this paper is to show how LCA(Life Cycle Assessment) is used as a tool to evaluate the environmental burdens associated with EMU(Electronic Motor Unit), especially one of main components, an interior panel. Thus, the LCA results are polished into the general environmental product declaration format to communicate with the industrial and institutional customers. The format includes the product information and environmental information. In the list of environmental information, profile is consisted of two major results from the LCA study. One is the inventory analysis and the other is the characterized impact results. The format shown in this paper can be the one of option to choose environmentally preferable product and suggestion aimed at the institutional consumer such as government procurement office and corporation's purchasing department.

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Calculation of Inductances in Permanent Magnet Type Transverse Flux Linear Motor (영구자석형 횡자속 선형전동기의 인덕턴스 산정에 관한 연구)

  • Lee, Ji-Young;Ryu, Ho-Gil;Hong, Jung-Pyo;Jung, Soo-Jin;Kang, Do-Hyun
    • Proceedings of the KIEE Conference
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    • 2003.07b
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    • pp.948-951
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    • 2003
  • The design and analysis of electrical machines often require analytical models for performance assessment and system simulation. Inductances are important parameters of these models. In this paper, the methods of calculating apparent and incremental inductances are introduced for a transverse flux linear motor, which has a peculiar coil shape. The computation is accomplished by nonlinear three dimensional finite element method(FEM) and equivalent magnetic circuit network(EMCN). The improved method has been verified by a test result.

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