- 學位論文
變電所架空地網防雷效能探討
Lightning Protection Performance of Overhead Wires of Substations
摘要
雷擊係自然界的現象之一，為避免設備遭直接雷擊，變電所多裝設有架空地線網，利用引線將雷突波導入地網，所以架空地線網的防雷效能對於電力系統的安全性和可靠度是很重要的。變電所的防雷效能亦與地網的特性息息相關，影響地網特性的主要因素有地網形狀、面積大小、雷電流注入點、雷電流波形、峰值和土壤電阻係數，這些特性都是地網設計者必須考量的重點。 目前變電所的防雷措施以裝設避雷針及架空地線為主，本論文利用滾球法來探討龍崎超高壓變電所345/161kV側架空地線的遮蔽效果，及利用ATP模擬變電所架空地網遭受雷擊時的暫態電壓，分析不同的雷擊位置、鐵塔塔腳電阻、雷擊電流、地網格距(Span)及雷擊電流注入點，對鐵塔塔腳電壓、接地引接線電流、架空地線電流、地網地電位升之影響。
並列摘要
The lightning stroke is the phonomena of nature, to prevent direct lightning stroke to equipments, the overhead ground wires are installed at most substations. The lightning surge is then drawn into the ground grid, so the lightning protection performance of overhead ground wires is very important to the safe and reliable operation of the power system. The lightning protection performance of substations is affected by the transient characteristics of grounding grids if the direct lightning happens. And the transient characteristics of grounding grids depend upon the shape and size of the grid, the feedpoint, the shape, and amplitude of the impulse current and soil parameters. The influence of these factors on the characteristics of grounding grids shound be taken account by designers. The major lightning protection methods of substations are the installation of lightning rods and overhead ground wires. The research takes the rolling method to analyze the protection performance of Long-Chi E/S of Taipowe. The ATP software was used to simulate the transient voltage of overhead ground wires if the direct lightning stroke happened. The simulation includes various lightning location, the grounding resistance of towers, the lightning current, feedpoint and grid spans to the voltage of tower’s foot, ground wires current, overhead ground current and Ground Potential Rise