電気学会論文誌A(基礎・材料・共通部門誌)
Online ISSN : 1347-5533
Print ISSN : 0385-4205
ISSN-L : 0385-4205
116 巻, 6 号
選択された号の論文の13件中1~13を表示しています
  • 岡本 達希
    1996 年 116 巻 6 号 p. 481-487
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
  • 乗本 幸治, 林 喬久, 伊藤 晴雄
    1996 年 116 巻 6 号 p. 488-493
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    We have measured negative ion mobilities at atmospheric pressure, in extremely low E/P0 from 0.019 to 1.8 V/cm•Torr. A cascaded gap, which consists of an ion drift gap and an ion detecting gap, is used for the experiment. The ion detecting gap is formed from positive point plane gap, so-called Geiger Counter. The measurement of the negative ion mobilities is made at atmospheric pressure. An obtained reduced zero field mobility of O-2 is 2.03±0.07cm2/V•s. This value is in good agreement with Snuggs, et al, but slightly smaller than that of Voshall, et al. Another ion mobility was detected for 1.0≤E/P0≥4.0V/cm•Torr region, and we presume that it is the value of negative ion of O3.
  • 藤岡 伸宏, 大垣 定彦, 川崎 一
    1996 年 116 巻 6 号 p. 494-502
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    This paper presents a comparison of the electrical performance of silicone rubber in two different tracking-test methods. One is a continuous tracking test which is similar to merry-go-round method. The other is an intermittent tracking test, in which the test is repeated according to the procedure of tracking test for one day and drying at 30° for two days.
    In the continuous tracking test, the leakage current increases consistently due to the development of surface degradation with an increase in aging time. Meanwhile in the intermittent tracking test, the initial current value after drying is almost zero due to the recovery of surface hydrophobicity. Then weak discharges occur and the value of the current increases rapidly due to the expansion of hydrophillic area.
    It is clearly demonstrated that the intermittent tracking test is more accurate for evaluating interactions of the loss and the recovery of surface hydrophobicity in the aged surface layer.
  • 森武 洋, 寺山 元和, 宇戸 禎仁, 不破 由晃, 尾崎 雅則, 吉野 勝美
    1996 年 116 巻 6 号 p. 503-509
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    Free-standing ultra thin films of ferroelectric liquid crystal of 7nm to 150nm in thickness have been prepared. The structure and electro-optical properties of these free-standing films have been studied by means of ellipsometry and electro-optical measurements. The Sm A and Sm C∗ phases have been observed in the free-standing films. The phase transition temperature between the Sm A and Sm C∗ phases has shifted to higher temperature with decreasing thickness of free-standing film. The molecular tilt angle in the induced Sm C∗ phase of free-standing film is independent of the thickness of the film and is smaller than that of bulk. The electro-optical response has been observed in the Sm C∗ phase of this free-standing film.
  • 岡部 成光, 向當 正典, 奈良 敏雄, 菅沼 紀美夫, 高橋 邦彦
    1996 年 116 巻 6 号 p. 510-515
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    Power capacitors are highly reliable equipment due to their completely enclosed configuration. They have usually worked without almost any trouble for a long time. Their dielectric strength can be however reduced due to some stresses such as over-voltage application or thermal degradation of the insulation material during their long period of operation and these events can result in the dielectric breakdown of the capacitors in extreme cases.
    Power capacitors with oil-impregnated paper-film are commonly used in substation. Therefore, it is very important to diagnose the deterioration and predict the remaining service life of such equipment, to assist in plant maintenance. To establish the diagnostic method of the deterioration of the capacitors with oil-impregnated paper-film, we have conducted thermally-and electrically-accelerated deterioration tests and investigated the changes of their characteristics. Based on the experimental results we obtained, it can be concluded that the behavior of the oil-dissolved gases can be used as a useful index to diagnose the insulation deterioration of these capasitors.
  • 小野田 光宣, Alan G. Macdiarmid
    1996 年 116 巻 6 号 p. 516-521
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    A new n-type conducting polymer poly (p-pyridyl vinylene), (PPyV) was synthesized by the C-C cross coupling reaction of 2, 5-dibromopyridine and 1, 2-bis (tributylstannyl) ethylene catalyzed by palladium complex. We have reported investigations of electroluminescence (EL) in PPyV which we have used in a range of single-and double-layer EL devices. EL in the yellow region of the spectrum with a maximum at 585nm was observed from PPyV sandwiched between indium-tin-oxide and Al electrodes. In double-layer device which incorporate a thin film of poly (p-phenylene vinylene), (PPV) as a hole transport layer, yellow-orange emission with 0.08% external quantum efficiency can be achieved. EL originates from the radiative decay of the chromophore singlet polaron exciton created as a result of the recombination of injected charge carriers.
  • 王 祁, 佐藤 愛実, 山崎 亨
    1996 年 116 巻 6 号 p. 522-528
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    A digital impedance measuring system based on the digital phase detecting system (DPD) has been developed for precise measurement of impedance. This measuring system consists of a personal computer with an ac-to-dc converter, a pair of current-to-voltage converters (CVC) and a frequency synthesizer. An unknown impedance and a standard resistor are connected to the frequency synthesizer in parallel. A ratio of the unknown impedance to the impedance of the standard resistor is calculated from the output voltages of the CVCs which are measured by means of DPD. The impedance of a capacitor of which nominal value is 0.1 μ F is measured at 50 Hz. It is estimated that the uncertainties of the measured values for capacitance and loss-angle are 0.006% and 0.05 mrad respectively excepting the uncertainty of the standard resistor.
  • 福山 達也, 伊藤 晴雄, 山本 耕司, 生田 信皓
    1996 年 116 巻 6 号 p. 529-535
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    Luminous layers in neon were first discovered in 1923 by Holst and Oosterhuis, and several studies have been reported. In order to understand the principle of the phenomenon, we have observed the spatial distribution of emission intensity and the current-voltage characteristics using a low pressure discharge tube. We have also carried out a Monte-Carlo simulation and found a good agreement between the simulated and measured intensity distributions. It was found that the instability in the negative current-voltage characteristics are related to the change of the number of luminous layers.
  • 村田 正男, 西村 政信, 白瀬 光章, 佐藤 利明, 松浦 光夫
    1996 年 116 巻 6 号 p. 536-544
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    PPLP is a prominent insulating material with high dielectric breakdown strength and low dielectric loss, which has been in practical use for OF cables in EHV/UHV transmission system. Neverthless, the dielectric breakdown mechanism of oil-impregnated PPLP system has not been cleared sufficiently.
    This paper demonstrates that the relationship between the ac partial discharge properties and the dielectric breakdown mechanism of an oil-impregnated PPLP can be clarified by using a needle-plate electrod system. In this paper, we came to the conclusion that the ac partial discharge properties of an oil-impregnated PPLP can be roughly devided into five types which are caused by the dielectric breakdown of each part in the oil-impregnated PPLP system: oil layer part, kraft paper part and PP-film part.
  • 大木 義路, 朝井 壮太郎
    1996 年 116 巻 6 号 p. 545-551
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    Discharging current which is measured after voltage application on a dielectric solid usually flows in the opposite direction to the applied field. Anomalous discharging current which flows in the same direction as the applied field is observed in polymethylpentene at temperatures higher than 100°C. The effects of electrical stress and voltage application period on the appearance of anomalous current were examined. On the condition when the discharging current becomes anomalous, layers of heterocharges accumulated during voltage application are observed with the pulsed electroacoustic method. The accumulated charges decrease significantly after the anomalous discharging current was observed for 5 minutes. On the assumption that charge movement is ruled by the electric field formed by space charges, simulation of discharging current was carried out. The simulated discharging current agrees well with the experimental data, when it is calculated by assuming the mobility of positive charge to be μp=2.5×10-10cm2/Vs and that of the negative charge to be μn=7×10-11cm2/Vs.
  • 井上 成美, 尾崎 立哉, 柏原 茂, 戸嶋 成忠, 藤本 良三
    1996 年 116 巻 6 号 p. 552-558
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    A new off-axis pulsed laser deposition method using a perforated plate is developed in order to deposit droplet-free Ta2O5 thin films. The droplet density of on-axis films is large at the center of the film. But that of off-axis films is small and the distribution of the density is independent of the position on the substrate. These results indicate that the perforated screening plate plays an important role of limiting the path of droplets. On the other hand the deposition rate is not diminished because the species are not trapped to the plate. The optimum oxygen pressure for depositing the droplet-free Ta2O5 films is from 200 to 300 mTorr at which the ratio between the increasing rate of droplets and that of film thickness becomes minimum.
  • 早乙女 英夫, 河井 武志, 榊 陽
    1996 年 116 巻 6 号 p. 559-565
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
    Iron loss measurement of Ni-Zn ferrite cores up to MHz range is carried out. In order to obtain the frequency characteristics of the hysteresis and eddy current losses in the cores, the electromagnetic fields at different frequencies are analyzed with the medium parameters, such as the complex permeability expressing the DC hysteresis, the conductivity and the pennittivity of the ferrites. The residual loss obtained by subtracting these computed losses from the measured iron loss increases in proportion to the square of the exciting frequency in MHz range. By introducing the dynamic magnetic loss parameter, it is clarified that the residual loss is directly produced by the magnetic field, but not directly caused by the electric field. As a result, it is assumed that the residual loss corresponds to the frictional loss of magnetic domain wall motion. Moreover, the dynamic magnetic loss parameter is expected to be a loss evaluation index for future ferrites because its value is peculiar to each ferrite material, independent of exciting conditions and core size.
  • 高倉 靖, 小野 茂, 堤井 信力
    1996 年 116 巻 6 号 p. 566-567
    発行日: 1996/05/20
    公開日: 2008/07/15
    ジャーナル フリー
feedback
Top