http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
박판 자성 재료를 이용한 전력 케이블 인근의 자기장 차폐
김상범(Sang-Beom Kim),소준영(Joon-Young Soh),신구용(Koo-Yong Shin),정진혜(Jin-Hye Jeong),명성호(Sung-Ho Myung) 한국전자파학회 2009 한국전자파학회논문지 Vol.20 No.7
본 연구에서는 자기장 차폐를 위하여 3상 전력 케이블을 얇은 자성 판재로 둘러싸는 방법을 제안한다. 두꺼운 상용 뮤-메탈, 방향성 및 무방향성 규소 강판을 출발 재료로 하여 두께 0.1 ㎜의 차폐재 3종류를 제조하였다. 3상 전류일 때, 차폐재 위치의 자기장이 100 μT 정도이면 뮤-메탈이(SF<0.1) 가장 효과적이었고, 500 μT 이상이면 규소 강판이(SF 0.3~0.4) 더 효과적이었다. 또한, 안쪽에 방향성 규소 강판, 바깥쪽에 뮤-메탈을 함께 둘러쌀 경우 500 μT까지도 SF를 0.1 이하로 할 수 있었다. 한편, 단상 전류에서는 고 투자율 소재의 적용은 오히려 자기장을 증가시키는 결과를 보였다. 이상의 결과는 자기장 강도 H의 크기에 따라 각 소재의 투자율 우열이 서로 다른 점과 이로 인해 차폐재 내에 유도되는 자기장 벡터와 원래의 자기장 벡터의 상호 상쇄 및 중첩 작용으로 설명할 수 있었다. In this work, wrapping conductors with thin magnetic materials is proposed as a magnetic shielding method. The 0.1 ㎜ thick metal sheets of mu-metal, grain-oriented electrical steel, and non-oriented electrical steel were produced from commercial alloy sheets through cold rolling and followed high temperature annealing. In case of 3-phase electric currents, mu-metal was the best in shielding performance at a B-field magnitude of about 100 μT, whereas silicon steels were better than mu-metal at a B-magnitude over 500 μT. In addition, wrapping with silicon steel(inner) together with mu-metal(outer) resulted in a shielding factor less than 0.1 even at 500 μT. These results are due to changes in hierarchy of magnetic permeabilities of the materials with increasing magnetic field strength. In case of single-phase electric current, B-magnitude outside the magnetic shell was rather increased compared to the unshielded case. This result is explained by vector composition of B-fields near magnetic shielding materials.
전기장 센서를 이용한 교류 400 ㎸ 고전압 분압기의 제작 및 평가
李相和(Sang-Hwa Lee),韓相吉(Sang-Gil Han),鄭在甲(Jae-Kap Jung),姜銓洪(Jeon-Hong Kang),金潤亨(Yoon-Hyoung Kim),鄭辰慧(Jin-Hye Jeong),韓相玉(Sang-Ok Han) 대한전기학회 2008 전기학회논문지 P Vol.57 No.3
Output voltage value of AC high voltage source has usually been obtained by measuring the low arm voltage of high voltage divider or the secondary voltage of high voltage transformer. In this study, we have fabricated the AC 400 ㎸ high voltage divider using high voltage electrode and electric field measurement sensor. The dividing ratio of the fabricated 400 ㎸ high voltage divider was evaluated using reference 400 ㎸ capacitive divider. The dividing ratio of 400 ㎸ high voltage divider is found to be 12,322 and has the good linearity within 0.63 % against AC high voltage up to 400 ㎸. Therefore, the developed 400 ㎸ high voltage divider could evaluate 400 ㎸ high voltage supply and voltage divider used in industry.
200 ㎸ 용량형 분압기 2대를 이용한 교류 고전압 측정범위 확장
鄭在甲(Jae-Kap Jung),李相和(Sang-Hwa Lee),姜銓洪(Jeon-Hong Kang),金明壽(Myung-Soo Kim),金潤亨(Yoon-Hyoung Kim),韓相吉(Sang-Gil Han),鄭辰慧(Jin-Hye Jeong),韓相玉(Sang-Ok Han),鄭鍾萬(Jong-Man Joung) 대한전기학회 2008 전기학회논문지 P Vol.57 No.1
The output voltage value of AC high voltage source has been usually obtained by multiplying low voltage value measured at both terminals of low voltage resistor by the dividing ratio of the high voltage capacitive divider. From the dividing ratio determined of each 200 ㎸ capacitive divider, we have developed step-up method for measuring the output voltage up to 400 ㎸ using two same type of 200 ㎸ capacitive dividers connected in series. The theoretical dividing ratio of 400 ㎸ capacitive dividers connected in series coincides with that of manufacturer's certification within measurement uncertainty. Thus, this developed step-up method makes it possible to extend the range of output voltage from 200 ㎸ to 400 ㎸, Furthermore. The dividing ratio of divider under test obtained using this step-up method is consistent with that obtained using one 200 ㎸ high voltage divider within corresponding uncertainties.