• Title/Summary/Keyword: no - insulation

검색결과 305건 처리시간 0.034초

Evaluation of Insulating Reliability in Epoxy Composites

  • Park, No-Bong;Yang, Dong-Bok;Lim, Jung-Kwan;Park, Yong-Pil;Lee, Hee-Kab;Kim, Gui-Yeul
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
    • /
    • pp.1200-1203
    • /
    • 2003
  • The dielectric breakdown of epoxy composites used for transformers was experimented and then its data were applied to Weibull distribution probability. First of all, speaking of dielectric breakdown properties, the more hardener increased, the stronger breakdown strength became at low temperature because of cross-linked density by the virtue of ester radical. The breakdown strength of specimens with filler was lower than it of non-filler specimens because it is believed that the adding filler forms interface and charge is accumulated in it, therefore the molecular motility is raised and the electric field is concentrated. In the case of filled specimens with treating silane, the breakdown strength become much higher. Finally, according to Weibull distribution analysis, reducing breakdown probability of equipment insulation lower than 0.1% level requires the allowable field allowable field intensity values to be kept under 21.5 MV/cm.

  • PDF

VAV/BPFS를 이용한 실내공기 오염물질의 효율적 제어 (Effective Control of Indoor Air Pollutant using VAV/BPFS)

  • 최성우
    • 한국환경과학회지
    • /
    • 제7권3호
    • /
    • pp.327-334
    • /
    • 1998
  • The oil crisis of the 1970s and the rise in oil prices motivated people to implement energy conservation strategies. Buildings were fitted with additional Insulation and reduced ventilation rates. The reduction of mechanical and natural ventilation rate led to Increases In Indoor pollutant concentrations which result- ed In Increased health risks from Indoor exposure to pollutants. The variable-air-volume /bypass fitration system/VAV/BPFS) is a variation of the conventional VAV systems, The VAV/BPFS is an electronically controlled system that provides costegectlve thermal comfort and acceptable indoor air quality Under controlled conditions In a chamber, a series experiments were performed to compare the ability of a VAV/BPFS to remove Indoor aerosol concentration and to reduce energy consumption no that ability of conventional VAV system. Results show that the VAV/BPFS Increases the effective ventilation rate and removes indoor air pollutant, and maintains acceptable indoor air Quality without sacrificing energy consumption.

  • PDF

철도차량용 전동기의 과제 (The Development of A.C. Induction Motor for Electric Railway Rolling Stock)

  • 윤승진;이인우;성기대;하현성;노철웅
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1995년도 추계학술대회 논문집 학회본부
    • /
    • pp.24-26
    • /
    • 1995
  • The Development of A.C. Induction Motor for Railway Rolling Stock. The traction motor is designed as 4-pole induction motor with self ventilation. The winding insulation is throughout of materials of class C. The rotor is designed as a squrrel rotor with copper bar and casting. The rotor speed is detected by means of a pulse generator. The newer tection motor have no casting(frame). Punched-in holes make up the air duct and transfer the heat losses in complete. Maximim motor rpm is higher due to rotor construction. New is the entry of water-cooled traction motors in urban, However the water cooling design in - unfortunately - not applicable in traction motor.

  • PDF

공동주택 수음실의 평면형태에 따른 중량충격음 특성 변화 연구 (A Study on the Heavy Impact Sound Insulation Performance of Apartments depending on the Shape of Receiving Room)

  • 기노갑;김항;최은석;김선우
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2006년도 춘계학술대회논문집
    • /
    • pp.1317-1320
    • /
    • 2006
  • This study compared the floor impact sound level of rectangular receiving room type to differed receiving room types to analyze effect of room mode. The floor impact sound level of master room were higher than the level of living room which resulted from room mode. The result showed that the level of low frequency bandwidth in the location varied with receiving room types were lower than general measuring point of rectangular receiving room.

  • PDF

무풍안정시의 부인용한복의 보온력에 관한 연구 -동제인체모형에 의한 실험- (Experimental Study on the Thermal Insulation of Woman's Korean-Styled Clothes under Still Air Condition -by the Instrumented Copper Mannequin on Standing-posture-)

  • 최정화
    • 한국의류학회지
    • /
    • 제1권1호
    • /
    • pp.7-13
    • /
    • 1977
  • The insulating values of 7 kinds of woman's Korean-styled clothes were examined on the instrumented copper mannequin standing upright under still air condition in a climatic chamber at $20^{\circ}C$ and $60\%$ R.H.. Results obtained are as follows: 1) High correlation coefficients were found in both between total insulating values of clothing (IT) and total clothing weight. and between IT and total clothing thickness while no significant difference was found between total clothing weight and total clothing thickness. 2) It seems possible to predict the approximate insulating value of woman's Korean styled clothes on still air condition by the total clothing weight.

  • PDF

표면방전의 집중에 따른 옥외용 설비의 성능평가 (The Estimation of Outdoor Insulation According to the Concentration of Surface Discharge)

  • 임장섭;정승천;이진;노진양
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
    • /
    • pp.212-216
    • /
    • 2001
  • The conventional tracking testing as IEC-60587 is widely used in surface aging measurement of outdoor insulator because those testing can carry out very short time in Lab-testing. Also IEC-60587 testing is able to offer the standard judgement of relative degradation level of outdoor HV machine/system. Therefore it is very useful method compare to previous conventional tracking testing method and effective Lab-testing method. But surface discharges(SD) have very complex characteristics of discharge pattern so it is required estimation research to development of precise analysis method. In recent, the study of IRR-camera is carrying out discover of temperature of power equipment through condition diagnosis and system development of degradation diagnosis. In this study, SD occurred from procelain insulator, used 22.9[KV] distribution, is measured with partial temperature distribution in real time, the degradation grade of SD is analyzed through produced patterns in SD concentration according to applied time.

  • PDF

외부환경적 가속시혐에 의한 PV모듈의 열화성능 분석 (Analysis of Photovoltaic module's Phenomena of aging with Acceleration Test)

  • 강기환;김경수;박지홍;유권종;안형근;한득영
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
    • /
    • pp.1151-1152
    • /
    • 2006
  • In this paper, we examined 10 domestic samples of three different model using thermal, humidity freeze, thermal-endurance and damp heat test under IEC61215 photovoltaic module environmental endurance test condition. Three was almost no changes on power generation. Insulation resistance capacity was much higher than judgement standard but, showed unstable results depending on environmental test items. On external appearance test, there were two models which showed bubble, humidity penetration, seal melted frame phenomenon. From this results, the degree of aging under the external environment is a main cause that shortens photovoltaic module life time. So it is considered that the efforts for finding optimum condition of manufacturing process should be needed.

  • PDF

Influence of polymer coating on SFCL recovery under load

  • Gorbunova, D.A.;Kumarov, D.R.;Scherbakov, V.I.;Sim, Kideok;Hwang, Soon
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제21권4호
    • /
    • pp.44-47
    • /
    • 2019
  • This paper is a study of recovery under load process of superconducting fault current limiter (SFCL). SFCL consists of five parallel-connected high-temperature superconductor (HTS) tapes additionally stabilized by stainless tape. Previously, HTS was heated by current pulse to simulate a short circuit in a power grid. During the cooling period, the current amplitude decreased to 23% or less of HTS critical current value, which is the simulation of network re-switching. When HTS with a polymer coating is cooled, temperature gradient on thermal insulation layer occurs, that prevents a boiling crisis and improves the heat sink into liquid nitrogen. Two samples are coated with a 30 ㎛ and 50 ㎛ polylactide (PLA) layers, reference sample has no polymer coating on it. Samples with a polymer coating show 3-5 times faster cooling than the reference one.

기포성형 압력변화에 따른 기포밀도 및 기포콘크리트의 물리적 성능에 관한 연구 (A Study on the Foam Density and The Physical Performance of Foam Concrete According to the Foam Forming Pressure Change)

  • 홍상훈;유남규;서은석;김해나;김봉주
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2018년도 추계 학술논문 발표대회
    • /
    • pp.38-39
    • /
    • 2018
  • Foame concrete was used to reduce insulation problems and interlayer noise in slab. There have been no studies on the physical properties of foaming agents using foamed concrete,Only the physical properties of foamed concrete mixed with foam agent. It is judged that the density and distribution of Foams will be changed when the pressre is changed when the bubble is formed. In this study to investigate the changes of Foam density and the physical performance of foamed concrete by changing the pressure during Foam formation.

  • PDF

건식 알루미늄 트러스 설치공법의 단열재 시공용 앵글개발 (Development of the angle assembly for insulator construction of the dry aluminum truss construction methodsystem)

  • 이영래;홍성욱;안태한;도선붕
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2013년도 춘계 학술논문 발표대회
    • /
    • pp.252-253
    • /
    • 2013
  • In this paper, we introduce the insulation of aluminum truss dry installation method for construction for the development of the Angle. Features of the development of anchor bolts have been identified as no risk of fire, and ease of construction, which has the advantage of being the adiabatic efficiency is increased. In future research, to study the angle of the field on the Application of the development for the construction.

  • PDF