• 제목/요약/키워드: Internal discharge

검색결과 652건 처리시간 0.028초

PDA를 이용한 고압전동기 고정자 권선에서 부분방전 특성 (Partial Discharge Properties of High Voltage Motor Stator Insulation using Partial Discharge Analyzer)

  • 김희동;이상길
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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    • pp.225-228
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    • 2001
  • Partial discharge(PD) testing for different capacitive couplers was performed on a 6.6kV, 448kW pulverizer motor. The motor has been in service for twenty years. PD tests were measured using digital partial discharge detector(DPDD) and partial discharge analyzer(PDA), respectively. PDA is used to in the motor stator insulation, which three 80pF or three 500pF epoxy-mica couplers were installed, one per phase. The 500pF couplers did detect more normalized quantity number(NQN) than the 80pF couplers. DPDD and PDA showed that PD and NQN magnitudes increased with increase of ac voltage. Internal discharge was discovered in the motor stator insulation. DPDD and PDA test results are in accordance with the pattern and magnitude of PD.

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고압전동기 고정자권선의 부분방전 특징추출 (Feature Extraction of Partial Discharge for Stator Winding of High Voltage Motor)

  • 박재준;김희동;이동윤
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.112-116
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    • 2004
  • On-line monitoring of fault discharge is an important approach for indicating the condition of electrical insulation of stator winding in high voltage motor. In this paper, several key aspects of on-line monitoring system are discussed, involving the characteristics of fault discharge of stator winding in high voltage motor, spectrum analysis of four simulation fault signals, feature extraction of internal fault discharge from apply voltage to breakdown. The study of the partial discharge activities allows to highlight the ageing stage in the winding fault under test. During the life of the winding insulation fault, the shape of PD signal change relating to the ageing stage. The ageing of stator winding insulation fault of high voltage motor is investigated based on the characteristics of partial discharge pulse distribution and statistical parameters, such as maximum, skewness and kurtosis using discrete wavelet transform coefficients.

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결함에 따른 견인전동기 고정자 코일의 부분방전측정 및 패턴분류 (PD Measurement and Pattern Discrimination of Stator Coil for Traction Motor according to Different Defects)

  • 장동욱;박현준;박영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.221-222
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    • 2005
  • In this paper, application of NN (Neural Network) as a method of pattern discrimination of PD(partial discharge) which occurs at the stator coil of traction motor was studied. For PD data acquisition, three defective models are manufactured such as internal discharge model, slot discharge model and surface discharge model. PD data for recognition were acquired from PD detector and DAQ board which is able to analysis the PD signal and perform the pattern discrimination. Statistical distributions and parameters are calculated to discriminate PD sources. And also these statistical distribution parameters are applied to classify PD sources by BP and has good recognition rate on the discharge sources.

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간장의 병리변화 인식에 대한 문헌적 고찰 (The Literatual Study on Pathologic Change Cognition to the Liver Disease)

  • 이영수;곽정진;이강녕;최창원;김희철
    • 동의생리병리학회지
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    • 제16권4호
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    • pp.630-636
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    • 2002
  • After The Yellow Emperor's Canon of Internal Medicine, The text researches of pathologic change to the liver disease concluded the next, 1, The category of liver-disease(肝病) include the Symptoms of abnormality due to vital energy and blood motion, emotion and intention, muscular and reproductive function, and legions around descending liver channel. 2. In the theory that Liver-Yang energy(肝陽氣) is always overproducing, Liver-Yin blood(肝陰血) is always lacking, pathologic characteristics for liver disease is functional change of malfunction of the use of body(體用失調), So nourishing the liver and kidney is used for the principal aspects of a disease. regulating and calm the liver is used for the secondary aspects of a disease as the treatment plan, 3. If malfunctioning of the functions of dispersion and discharge(疏泄), Iiver-energy(肝氣) is becoming degected, So overproduct and overflow of ascent and exhalation of liver-yang(肝陽) is becoming blood are ascending following energy. complete usage of Yin-blood(陰血) is responsible for some kinds of mass formed by blood stasis in the early stage of pathogenesis of liver disease syndrome of the energy system as the progession of disease extravasated blood is forming. the pathologic characteristics is appeared loss of control of the vital energy and blood(體用失調) at the liver disease. 4. Sthenia-syndrome of liver(肝實證) and liver-heat syndrome(肝熱證) is appered that overproducing and overflow of dispersion(疏泄太過) and discharge is responsible for overfunctioning of liver disease or some kinds of heat syndrome such as liver fire(肝火), Sthenia of liver-yang(肝陽上亢), the syndromes of sthenic liver heat(肝實熱) are appered. deficiency of the liver(肝虛證) and cold syndrome of liver(肝寒證) is classified pathologic characteristics of cold and heat, deficiency and excess that regression of sensory, motor, mental due to lack of dispersion and discharge(疏泄不及), or intruding of the cold miasma, are degected. 5. The liver is close relation of physiologic function and internal organ such as spleen, stomach, lung, heart, kidney, gall bladder by the meridian channels, because of property of wind Zang, rapid progession is classified by phthologic charateristics.

고압회전기 고정자 권선의 부분방전 측정 (Partial Discharge Measurements of High Voltage Rotating Machine Stator Windings)

  • 김희동;이영준;공태식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1828-1830
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    • 2003
  • Partial discharge(PD) tests are used to evaluate the insulation condition of stator windings in two 4.16kV and three 6.6kV motors. These tests were conducted using a conventional partial discharge detector(PDD) and turbine generator analyzer(TGA). Off-line PD measurements were performed on five high voltage motors. PD magnitudes ranged from 1000 pC to 5400 pC at the normal line-to-ground voltage. Five high voltage motors have been equipped with 80pF epoxy-mica coupler on the motor terminal box. The PD pulse from sensors were measured with the TGA instrument. TGA summarizes each plot with two Quantities such as the peak PD magnitude(Qm) and the total PD activity(NQN). The defect mechanisms of high voltage motor can be associated with PD patterns such as internal, slot and conductor surface discharges. The PDD and TGA test results of No. 4 motor showed that internal discharge was detected in voids of the groundwall insulation.

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PubMed를 통해 살펴 본 알레르기 비염에 대한 보완 의학적 최신 연구 경향 (Study of Complementary Medical Therapy for Allergic Rhinitis in PubMed)

  • 정혜미;조민정;서운교
    • 대한한방내과학회지
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    • 제30권3호
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    • pp.534-549
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    • 2009
  • Objectives : To study trends in complementary medical therapy for the allergic rhinitis. This study analyzed research on allergic rhinitis in PubMed. Methods : We searched PubMed related to complementary medical therapy for allergic rhinitis. We analyzed 25 research papers and examined published journals, years countries, and their methods, objectives, results, interventions, participants, periods and instruments of assessment. Results : The method of studies was mostly randomized, double-blind, placebo-controlled trial. There were research papers concerning treatment and prevention with herbal medicine, acupuncture, diet, etc. There were more positive results compared to negative results for treatment and prevention. Most studies were carried out during the winter/spring period. The median for number of participants was 90.54 persons. Diagnostic criteria for enrolment were nasal symptoms, allergic skin test, serum, nasal discharge allergen specific IgE eosinophil, etc. Assessment for outcomes were nasal symptoms, serum, nasal discharge allergen specific IgE eosinophil and Quality of Life Questionnaire. Conclusions : It is necessary to study effects of acupuncture and herb medicines for allergic rhinitis and more in-depth research about trends in complementary medical therapy for allergic rhinitis.

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Acute Viral Hepatitis A with Cholestatic Hepatitis Treated with Traditional Korean Medicine : A Case Report

  • Kim, Jun-Young;Joung, Jin-Yong;Kang, Ji-Young;Son, Chang-Gue;Cho, Jung-Hyo
    • 대한한의학회지
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    • 제36권4호
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    • pp.114-121
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    • 2015
  • More and more patients suffering from hepatitis A, the number of patients representing symptoms that are uncharacteristic to hepatitis A is also increasing. There are occasions of serious complications among adult hepatitis A patients that can cause fulminant hepatitis or cirrhosis which can be fatal. A 43-year-old male was diagnosed as acute hepatitis A and was treated at a Western hospital over the course of three months, which included two months of hospitalization. However, his symptoms did not improve, so he was admitted to Oriental hospital. We prescribed Chunggan extract (CGX) four times a day. Acupuncture was performed twice a day. From the twenty-fourth day of admission, the total bilirubin fell under 10 mg/dL for the first time and next day he was discharged. Following his discharge, he consistently took CGX three times a day. 21 days after discharge all of his symptoms disappeared. This study demonstrated that traditional Korean medicine (TKM) for acute viral hepatitis with cholestatic hepatitis might be effective and safe with no adverse effects.

뇌졸중환자(腦卒中患者) 96례(例)에 대(對)한 임상적(臨床的) 고찰(考察) (Clinical study on the 96 Cases of Stroke patients)

  • 용형순;고성규
    • 대한한방내과학회지
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    • 제19권1호
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    • pp.85-96
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    • 1998
  • This study was done with 96 cases of stroke patients who admitted to Department of the circulatory internal medicine Sang-ji University oriental Hospital from January to December in 1997. The purpose of this paper is to predict prognosis in stroke patient and to estimate change of muscle motor power between admission and discharge day in Sasang Constitution. The results are as follows. 1. Motor function of upper extremities was improved one stage at discharge day compare to admission day and the function of lower extremities had no change in muscle motor power. 2. Especially March and April had high morbidity any other months and the time of onset was most frequent on the morning. 3. They had hypertension as first preceding disease, and the next was stroke. Stroke occurred most frequently in resting, and the next was in sleeping. 4. In Sasang constitution, Taeyum-in(太陰人), 47.9%, was most neumorous, the next was Soyum-in(少陰人), 36.5%, and the third was Soyang-in(少陽人), 15.6%.

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뇌간경색환자에 대한 임상적 고찰 (A Clinical study on the patients of Brain stem infarction)

  • 박규택;김영균;권정남;박숙자
    • 대한한방내과학회지
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    • 제21권5호
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    • pp.729-738
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    • 2000
  • Objective : We examined patients admitted to Dong Eui University Oriental Medical Hospital from 1st January to 31st December in 2000. We studied 110 cases of patients who were diagnosed as Brain stem(pons, mid brain, medullar) infarction with brain CT, MRI scan, MR Angiography. Methods : We analyzed patients into sex, age, onset time, invasion lesion, past and family history, risk factor, abnormal vital sign for early 2 weeks, prodromal symptoms, symptoms at entry, progress and incidental symptoms at acute stage, complications, the state of condition at discharge, demonstrations, herb medications, western and oriental medical cooperation and admission period. Results : Our study was similar to existing studies in the distribution of sex, age, past and family history and risk factors. But there was some differences in the prodromal symptoms, symptoms at entry progress and incidental symptoms at acute stage, and the state of condition at discharge. Conclusions : Our study shows the brain stem infarction patients differed from other cerebrovascular accident patients in the symptoms. We hoped that our study would be further studied in western and oriental medicine.

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환경개선을 위한 형광방전등형 오존발생기의 특성 (Characteristics of Fluorescent Discharge Lamp Type Ozonizer for Environment Improvement)

  • 박용권;이상근;전병준;송현직;이광식;하장호
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제51권10호
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    • pp.500-505
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    • 2002
  • In this paper, fluorescent discharge type ozonizer has been designed and manufactured. Ozone discharge and generation characteristics have been investigated in accordance with a sort of internal electrodes, output voltage of power supply, air flow rate and discharge power. Air has been used as the supplied gas of the ozonizer In this paper, when disuse fluorescent lamp was used as an internal electrode. Air flow rate was varied from 2[1/min] to 10[1/min]. The maximum ozone concentration and yield were 3495[ppm] and 23.4[g/kWh] respectively at 2[1/min] air flow rate and 35.2[W] input power. Illumination was appeared as 5[lx] within 15[cm] from external electrode. Whorl fluorescent discharge type ozonizer was used, air flow rate was also varied from 2[1/min] to 10[1/min]. At this moment, the maximum ozone concentration and yield were 2824[ppm] and 21.7[g/kWh] respectively at 2[1/min] air flow rate and 30.5[W] input power. Illumination was also appeared as 5[lx] within 15[cm] from external electrode like used fluorescent lamp.