典型交流電氣軌道回流系統是由回流軌、架空地線及均壓線構成之系統,電車電流經由此系統回流至牽引動力變電站,其均壓線之設置對電流之分佈有關鍵的影響,進而影響軌道電位及軌道洩漏電流,有必要加以探討,本文以台鐵系統東部幹線為例進行分析。 首先探討該回流系統之行車鋼軌、架空地線、均壓線等各相關設備之配置及電氣參數,並應用電磁暫態分析程式之改良程式ATP(Alternative Transients Program)以建置模型並進行分析,其中考量於軌道沿線以不同均壓線間距之配置,分析列車於不同位置時之軌道電壓、電流及架空地線、均壓線之回流電流分佈狀況;這些分析結果將佐以現場量測驗證,其中採用多通道記錄器進行電車線靜態測試及電力列車行進間回流電流量測,以驗證電車線系統阻抗值,及驗證鋼軌與架空地線之回流電流與回流率,藉此進一步探討電車線之均壓線配置與減少鋼軌電流洩漏至大地的關係。經由分析及量測結果均顯示均壓線採較密集配置時其回流電流率僅可稍微提高,故均壓線之增設尚需考慮相關因素,才能得到最大效益。
Typical AC electrification current return system (ECRS) is composed of three parts: return current rails, earth wires (return feeders), and equalized bonding wires (EBWs). Electrification current returns to the traction power substations through this system. Notably, the setting of EBWs has critical influence on the distribution of currents, and then may affect rail voltage and rail leakage current. Therefore, a systematic investigation is necessary. Herein, this thesis takes Eastern Line of Taiwan Railway system as an example for analysis. First of all, the paper explores the configuration and electrical parameters of the return current rail, the earth wires, the EBWs of the ECRS. Then, modeling and analysis based on the alternative transients program (ATP) of electromagnetic transient analysis program are presented. Through setting different spans of the EBWs along the railway, the rail potential and current, the current distribution on the earth wire and EBWs, at different train locations are analyzed. In addition, a multi-channel recorder is used for the measurements on system impedance, return currents and current rates of rail and earth wires, and to study the relationship between the configuration of EBWs and the reduction of current leakage to earth. Analysis and measurement results show that the return current rate can be increased slightly by the layout of denser deployment of EBWs. Here, other related factors should be considered for determing the increase of EBWs.