• 제목/요약/키워드: Lightning protection angle

검색결과 2건 처리시간 0.013초

A Novel Approved Mathematical Equation for Lightning Protection Angle

  • Singhasathein, Arnon;Rungseevijitprapa, Weerapun;Pruksanubal, Aphibal
    • Journal of Electrical Engineering and Technology
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    • 제13권2호
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    • pp.1021-1029
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    • 2018
  • During the past few decades, the lightning protection angle (${\alpha}$) has been proposed through several technical matters, namely graphical technique, numerical data and mathematical equation respectively. Nevertheless, these techniques are very complicated, and are difficult to utilize because they also contain several constraints practically. Hence, this paper proposes a novel equation of the lightning protection angle, which is a simple correlation, concise and easy to be implemented. Furthermore, the reliable result of this equation can confirm accuracy through comparative analysis with all previous techniques. As a result, these solutions are altogether equivalent. This novel equation can analyze the lightning protection angle of the vertical air termination system installed at the vertex of the royal pagoda in a Khema-pirataram temple which is at high risk due to lightning flashes.

Impedance Calculation of an Underground Transmission Cable System Installed with a Sheath Current Reduction Device

  • Jung, Chae-Kyun;Lee, Jong-Beom;Kang, Ji-Won;Wang, Xin Heng;Song, Yong Hua
    • KIEE International Transactions on Power Engineering
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    • 제4A권4호
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    • pp.236-242
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    • 2004
  • Previous research results indicated that the designed current reduction device could effectively reduce the sheath circulating current and that its RDP protection device could shield it against both fault and lightning strokes. In this paper, cable impedance is analyzed using wavelet analysis and distance relay algorithm following the installation of these devices so that the operation of distance relay can be estimated. The test results confirm that in these devices, the fault inception angle and SVL bonding types have no impact on the change of cable impedance. In other words, the conventional distance relay can be used without a new relay setting. Thus we can finally assert that the designed current reduction device and its protection device are effective and can be safely installed on the cable transmission system without disturbance.