|کد مقاله||کد نشریه||سال انتشار||مقاله انگلیسی||ترجمه فارسی||نسخه تمام متن|
|703273||891131||2015||6 صفحه PDF||14 صفحه WORD||دانلود کنید|
2. فرآیند اتصال
4. تئوری و محاسبات
5. نتیجه گیری ها
• We address the vulnerability under lightning conditions of stretches of the 1500 km long electrical transmission line with tall towers over dense Amazon forest canopy and river crossings.
• We develop a simplified LPM model to assess the line vulnerability to lightning incidence under EGM methodology.
• We use lightning density information based upon 50 million lightning events to establish the line vulnerability.
• The methodology presented in this work complements the Armstrong & Whitehead EGM protection method, and also agrees with normal engineering results in the calculation of the lightning flashover rate.
• We suggest its usefulness as a first-hand tool in the evaluation of transmission line projects and operational risk assessment in the Amazon region.
The vulnerability under lightning conditions of stretches of the 1500 km long electrical transmission line Tucurui–Oriximina–Manaus over dense Amazon forest canopy and river crossings is evaluated using a leader progression model (LPM) called ModSalto. We find vulnerability windows (low protection or unsafe) in all crossing stretches that use high towers to comply with environmental restrictions. The values of lightning flashover rates (LFR) reach 0.8277 flashover/year or an equivalent period of 14.49 months for stretches of river crossings, and 0.3403 flashover/year or an equivalent period of 35.26 months for stretches of forest canopy crossing. These numbers are above the computed equivalent ANEEL bidding figure of 0.15 flashover/year for that TL. This methodology uses a map of yearly lightning frequency produced with data from STARNET and SIPAM LLS and the level of lightning protection was evaluated with the electro-geometric model (EGM).
Journal: Electric Power Systems Research - Volume 119, February 2015, Pages 287–292