Newsletter 高速鐵路簡訊 . 交通部高速鐵路工程局
機場捷運系統22kV RMU介紹 Introduction to the 22kV RMU in the TIAA MRT System
左.三路22kV RMU外觀。右.四路22kV RMU外觀。

機場捷運系統供電工程於每一車站內皆設置兩座車站設施變電站(SSS),分由主變電站(BSS)引入22kV電力,經由22kV環路開關(RMU)連接至站內22kV/380V低壓變壓器,提供該車站低壓用電需求。BSS與各SSS間採雙饋線開迴路設計,當其中一迴線電力電纜因維修或故障無法提供電力時,將透過中央監控系統(SCADA)之規劃程序及22kV開關切換作用,由另一迴線繼續維持系統內各SSS所需電力,進而提高系統供電可靠度。
各車站RMU設備因應系統架構需求及為達成系統電力轉供功能,分別採數量不等之開關組合型式,以六氟化硫(SF6)氣體作為絕緣介質,內部開關皆置於填充一定壓力SF6絕緣氣體的不銹鋼容器內,以提供最佳之絕緣效果;斷路器採用真空斷路器(VCB),在密封真空室內啟斷電流及滅弧,不會污染其它氣室;負載啟斷開關(LBS)則採用吹弧方式消弧,以安全而穩定地開斷回路。系統內之RMU開關分別有三路(3-way)及四路(4-way)兩種型式。三路RMU開關係作為相鄰SSS間電力傳輸用,四路RMU開關除引接BSS站電源外,尚須將電力傳送至相鄰其他車站,以達到電力傳輸功能;三路RMU是由二組LBS及一組VCB組成,四路RMU則由三組LBS搭配一組VCB,VCB用以連接車站內22kV/380V低壓變壓器回路,以提供低壓用電,其餘回路則採用LBS,供應電源至相鄰SSS。各回路均配置有接地開關(ES)、隔離開關(DS)、保護電驛及壓力顯示裝置等,當SF6壓力過低時,環路開關會自動閉鎖電氣操作,確保設備在正常壓力狀況下始可操作。此外,VCB、LBS與ES間皆設有操作機構連鎖裝置,避免人為誤動作,以確保安全操作之原則。

The power supply distribution in the TIAA MRT System includes two sets of SSS in each station. The BSS induces 22kV electricity through the RMU to the 22kV/380V low-voltage transformer to provide the station with required low-voltage electricity. There is a double feeder line with open loop design between the BSS and each SSS so when one loop fails due to maintenance or malfunction, the other loop can maintain power output for each SSS via SCADA operational instructions and 22kV switch which results in enhanced power supply reliability.
To achieve system structural require-ments and power output transforming functions, the RMU equipment in each station have various number and switch combinations. To achieve the best insulation condition, SF6 is used as insulation media and the interior switch sits in a stainless steel container filled of SF6 insulation gas under a certain pressure. The vacuum circuit breaker (VCB) operates and performs arc extinction in a vacuum room so it will not contaminate other rooms. The LBS performs arc extinction by air-blasting to safely and stably break the circuit. There are two types of RMU switches, the 3-way and 4-way type. The 3-way RMU switch acts as the power transmission between adjacent SSSs. As for the 4-way RMU switch, it connects to the BSS and transports the BSS electricity to adjacent stations. The 3-way RMU switch comprises of two sets of LBS and one set of VCB; the 4-way RMU switch comprises of three sets of LBS and one set of VCB. The VCB connects to the 22kV/380V low-voltage transformer circuit in the station to provide low voltage electricity and the rest of the circuit power runs through LBS to provide power output to adjacent SSSs. Each circuit is configured with ES, DS, protection relay and pressure display device. When the SF6 pressure is too low, the RMU will automatically switch to closed-power operation to ensure that the equipment can be operated under normal pressure conditions. Additionally, there are interlocking devices between the VCB, LBS and ES to prevent human error and ensure operational safety.

  • 分享: