고압전동기 고정자권선의 절연결함에 대한 특징추출기법

박재준,이성룡,문대철,Park Jae-Jun,Lee Sung-Young,Mun Dae-Chul 한국전기전자재료학회 2006 전기전자재료학회논문지 Vol.19 No.10

Multi-resolution Signal Decomposition (MSD) Technique of Wavelet Transform has interesting properties of capturing the embedded horizontal, vertical and diagonal variations within an image in a separable form. This feature was exploited to identify individual partial discharge sources present in multi-source PD pattern, usually encountered during practical PD measurement. Employing the Daubechies wavelet, feature were extracted from the third level decomposed and reconstructed horizontal and vertical component images. These features were found to contain the necessary discriminating information corresponding to the individual PD sources and multi-PD soruces.

환경조건의 변화에 따른 EPDM 애자의 표면 오손정도의 진단기술

박재준,최인혁,김정부,Park, Jae-Jun,Choi, In-Hyuk,Kim, Jeong-Boo 한국전기전자재료학회 2004 전기전자재료학회논문지 Vol.17 No.10

The waveforms of the leakage currents for the surface discharge according to the degree of salt contamination and the variation of environmental condition on the EPDM polymer insulators, were shown in this paper. The variation phenomena of fundamental wave, 3rd and 5th harmonic waveforms were also shown from the beginning of the applied voltage and to the flashover voltage. To develop the technique of percentage contamination degree of EPDM polymer insulator according to the variation of environmental condition, the distortion degree of 3rd and 5th harmonic wave to the fundamental wave was utilized through the spectrum analysis for the waveforms of leakage current in the simulation of salt and fog test. The fact that distortion degree % of 3rd and 5th harmonics for fundamental wave is a necessary indicator for the assessment of contamination degree for the polymer insulators, was known.

에폭시수지의 고전압 전원주파수 변화에 따른 장시간 전기적 트리잉 열화 특성연구

박재준(Park Jae-Jun) 대한전기학회 2013 전기학회논문지 Vol.62 No.11

Electrical tree structure is one of the most important influencing factors for electrical treeing characteristics in polymers. In this paper, we focused on the structure characteristics of electrical treeing in epoxy resins (original) insulation under different high-frequency voltages (60, 500, 1000 ㎐). Effects of voltage frequency on the ac electrical treeing phenomena in an epoxy resins were carried out in needle-plate electrode arrangement. To measure the treeing initiation and propagation, and the breakdown rate, constant AC of 10 ㎸ with three different voltage frequencies (60, 500 and 1,000 ㎐) was applied to the specimen in needle-plate electrode specimen at 30 ℃ of insulating oil bath. At 60 ㎐, the treeing initiation time was 360 min and the propagation rate was 6.85×10-4㎜/min, and the morphology was dense branch type. As the voltage frequency increased, the treeing initiation time decreased and the propagation rate increased. At 1,000 ㎐, the treeing initiation time was 0 min and the propagation rate was 7.81×10-2㎜/min, and the morphology was dense bush type.

초음파 분산을 이용한 Epoxy-Organoclay 나노콤포지트 구조적 그리고 유전특성에 관한 연구

朴材俊(Jae-Jun Park) 대한전기학회 2008 전기학회논문지 Vol.57 No.9

The effect of the organoclay_10A nanoparticles on the DSC and Structural and Dielectrics Propertiest(1㎐-1㎒) for epoxy/Organoclay_10A Nanocomposites has been studied. Dielectric properties of epoxy-Organoclay nanocomposites were investigated at 1, 3, 5, 7, 9 filler concentration by weight. Epoxy nanocomposites samples were prepared with good dispersion of layered silicate using power ultrasonic method in the particles. As structural analysis, the interlayer spacing have decreased with filled nanoparticles contents increase using power ultrasonic dispersion. The maximum increase interlayered spacing was observed to decease for above 5wt% clay loading. The other hand, as decrease with concentration filler of the layered silicate were increased dispersion degree of nanoparticles in the matrix. The interesting dielectric properties for epoxy based nanocomposites systems are attributed to the large volume fraction of interfacesin the bulk of the material and the ensuring interactions between the charged nanoparticle surface and the epoxy chains.

에폭시기반 나노콤포지트의 고온부에서 트리잉현상

박재준(Jae-Jun Park),조대령(Dae-Ryung Cho),엄지용(Ji-Yong Um),윤여욱(Yo-Wook Yun),백관현(Kwan Hyun Baek) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.10

물리적 분산기법으로 초음파와 균질기를 동시에 적용한 분산기법을 이용하여 에폭시 기반 층상나노실리케이트를 충진한 에폭시­나노콤포지트 제조하였다. 유리천이온도 특성으로 무충진 에폭시수지와 층상실리케이트가 충진된 나노콤포지트의 비교에서 9.2℃가 상승되는 결과를 얻었다. 고온부인 130℃ 환경온도에서 장시간 트리잉 절연파괴측정에서 무충진에폭시 수지에 비하여 나노콤포지트가 절연파괴시간이 13.39배 늦은 시간에 파괴되었고, 트리진전속도의 경우 나노콤포지트가 13.9배 늦은 지연속도를 나타내었다.

HVDC Cable 및 접속재에 관한 견해

박재준(Park Jae-Jun),이보인(Lee Bo-In),김병준(Kim Byoung-Jun) 대한전기학회 2022 전기의 세계 Vol.71 No.3

증가하는 재생 및 신에너지의 통합 그리고 국제 전력 거래(international power trades)는 new HVDC 전송 시스템이 건설되고 개발을 가져왔다. 특히 HVDC Cable은 손실이 적고 신뢰성이 높은 해저 송전 및 해양 재생 에너지 통합(offshore renewable energy integration)에 중요한 역할을 한다. 본 논문에서는 HVDC 케이블의 현재 상용화 가능성과 다양한 유형의 HVDC 케이블 및 액세서리(cables and accessories)를 검토하고자 한다. 인가전압, 온도의존 전도도 및 공간 전하 누적의 원인으로 인한 불균일한 전계 분포가 주로 XLPE Extruded Cable과 접속재(joints)에 검토되어지고 있다. With the increased use of renewable energy sources and international power trades, development of HVDC transmission systems have emerged. In particular, HVDC cable has performed a major role for offshore renewable energy integration thanks to low power loss and high reliability performance. In this article, we will discuss commercialization of HVDC cables and review various type of cables and accessories for HVDC applications. In particular, the issue of inhomogeneous electric field distribution, which is caused by applied voltage, temperature dependance and space charge accumulation, is explored.

표면개질된 나노 알루미나의 에폭시-나노 콤포지트 유전 특성

박재준,Park, Jae-Jun 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.10

The aim of this study is to improve of dielectric properties using epoxy/nano alumina composites with adding glycerol diglycidyl ether (GDE:1,2 g). This paper deals with the effects of dielectric properties(${\epsilon}^{\prime}_r$ and $tan{\delta}$) for epoxy/nano alumina contents (1,3 phr) and GDE addition (1,2 g)composites. 5 kinds specimen were prepared with containing epoxy resins, epoxy nano alumina composites. Average particle size of nano used were 30 nm. The nano alumina used were gamma phase particles of spherical shape. The suppression of epoxy chain motion by addition of nano alumina+GDE decreased dielectric loss and relative permittivity magnitude.

인버터서지용, 유/무기 나노 하이브리드 코일의 온도스트레스에 따른 절연파괴 수명

박재준(Jae-Jun Park) 대한전기학회 2019 전기학회논문지 Vol.68 No.2

The one nano hybrid rectangular coil was fabricated by dispersing SiO₂ in PAI resin using a sol / gel method, and the another nano hybrid rectangular coil was fabricated by adding a flexible agent. To evaluate the dielectric breakdown lifetime, the dielectric breakdown lifetime was measured according to the change of temperature environment (30, 70, 100, 130, 150, 200℃) under an inverter surge (1.5kV/20kHz). Compared to the PAI original coil, the dielectric breakdown lifetime of the nano hybrid rectangular coil at 30℃ was improved by 23.23 times. The dielectric breakdown lifetime of the nano hybrid rectangular coil without the flexible agent was longer than that with the flexible agent at 100℃ or less. However, at 100℃ or higher, the life time of the dielectric breakdown of the rectangular coil added with the flexible agent was further improved.

인버터 서지와 온도 스트레스 하에서 Magnet Wire 절연 수명평가

박재준,Park, Jae-Jun 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.10

Coil specimen was prepared by coating a copper wire with two varnish thin layers: the first was polyamideimide (PAI)/nanosilica (5 wt%) varnish and the second was anti-corona PAI/nanosilica (15 wt%) varnish. Insulation breakdown voltage was investigated under inverter surge condition at $20^{\circ}C$, $70^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$, $250^{\circ}C$, respectively. The insulation lifetime of the two layered coil was tens of times longer than that of original PAI coil. And the insulation lifetime decreased with increasing ambient temperature because there was weak binding strength between copper and varnish layer.

에폭시/마이크로/나노알루미나 콤포지트의 부분방전 저항성특성

박재준(Jae-Jun Park) 대한전기학회 2016 전기학회논문지 Vol.65 No.6

Neat Epoxy, nano alumina composites, micro alumina composites and multi-nano alumina composites were prepared and experiment were performed to measure their partial discharge resistant characteristics. The partial discharge resistance obtained for the microcomposites, nanocomposites and multi-nanocomposites are compared with those of unfilled epoxy and with GDE amount for surface modifier. It was observed that compare multi-nano alumina composites to micro alumina composites, the partial discharge resistance to degradation gets improved considerably. The improvement in the degradation resistance is attributed to the interface intension between the nano alumina composites and GDE , micro alumina and epoxy neat.