台北捷運北投機廠邊界轉換軌電蝕分析

The Corrosion Analysis of Transfer Track in Depot Peitou Boundary of the Taipei Rapid Transit System

周皇佑(Huan-Yu Chou)

指導教授 ： 何金滿

中原大學/工學院/電機工程研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300187

摘要

摘 要

捷運系統為防治雜散電流之傷害，而於捷運各機廠與主線軌道間施以電氣隔離，然在不同接地系統間因該電流所產生之電位差正是造成軌道電蝕之最大成因，當電車鋼輪跨越兩個不同接地系統間，瞬間將兩邊電位差短接成同一電位，並產生一電弧導致軌道電蝕，故軌道對地電位變化及電車之負回流與軌道電蝕有密切關聯性。

藉由描述軌道電力系統各種接地方式的回流路徑所產生之軌道對地電位，來解說在機廠邊界鋼軌夾膠絕緣接頭（IRJ：Insulating Rail Joint）燒毀及其軌道電蝕問題。本文將以機廠之接地、非接地系統與主線之二極體接地系統的軌對地簡單模型，說明軌道對地電位及軌道電蝕的成因，並就實務進行探討與研擬如何防治。

文中將介紹軌道參數量測之方式，並建立軌道電路模型，以實際量得之各種軌道參數放進此一電路模型中進行模擬，就模擬結果與量測結果比對並加以分析，以作為軌道電蝕的探討與防治的參考。

針對捷運機廠邊界軌道電蝕的防治及改善對策，本論文有以下三點建議：（1）避開機廠駐車區鋼軌直接接地時收發車、（2）避開主線軌道對地電位突昇時收發車、（3）提高機廠軌道的對地洩漏電阻。希望透過上述探討，提出有效防治捷運機廠邊界軌道電蝕的措施，並希望對後續的進一步相關研究能有所助益。

關鍵字

軌道對地電位 ； 接地系統 ； 軌道對地電阻

並列摘要

Abstract

In order to prevent the damages of stray currents, the mass rapid transit（MRT） system has electrical insulation between the MRT depot and the main line tracks, however, the potential difference of different grounding systems is the most important factor of electrical corrosion on tracks. When steel wheels of train stride over two different grounding systems, they momently short the different potentials, and produce an electrical arc that causes track corrosion. Therefore track corrosion is close relate to the track to ground potential and the return currents of trains.

By describing the paths of track to ground stray currents of different kind of groundings, we can explain the problem of burnout of IRJ（IRJ：Insulating Rail Joint）and electrical corrosion of the track in the depot boundary. This paper will discuss the cause of potential difference between track and ground, and track corrosion by analyzing the simple models of the track for direct to ground, ungrounded, and through-diode ground systems.

The way to measure the track parameters will be introduced and the models of the electric circuit of the track will be established in this paper. And simulation and field test will be carried out to compare and verify for future reference to prevent track corrosion by stray currents.

For reducing corrosion on IRJ in depot boundary of the mass rapid transit system, this study offers the following three suggestions：

(1) Don’t receive and/or dispatch train when the rails of depot area are in solid ground situation.

(2) Don’t receive and/or dispatch train when track to ground potential of main line is too high.

(3) Increase track to ground resistance in depot area.

並列關鍵字

track to ground potential ； grounding system ； track to ground resistance

參考文獻

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