以延滯基準研發多車種基本列車當量模式

Abstract

在軌道系統中，為了滿足不同旅運需求，營運單位常提供多種不同的列車服務，而這些特性不同的列車同時行駛於相同路段中，將提升路網的異質性，對於容量有顯著的衝擊。然而，過去的容量計算方式，常根據可接受延滯下通過路段之最大列車數，直接總計所有列車，忽略了列車異質性及其影響，易錯估鐵路容量。因此，本研究提出多車種基本列車當量模式，藉由相同延滯之下可通過路段之基本列車單位應相同之中心概念，建立起基本列車當量運算模式，並可根據基本列車當量，轉換不同列車成為同一列車單位，評估流量於路段中之實際影響。 基本列車當量模式建立於容量分析方法之基礎上，因此重要影響參數與影響容量之因子皆相同，包含路段條件、列車特性與營運特性等三大類。爰此，基本列車當量之數值也隨著參數組合之不同而變化，然而對於單一路段而言，最重要的影響因子便為流量與列車異質性，本研究首先提出動態列車當量模式，可根據不同的流量與列車異質性組合計算其對應之列車當量值。然而，根據分析之結果可以發現，列車異質性對於基本列車當量之影響，遠大於流量之影響，為了增進計算的方便性，本研究更進一步提出固定列車當量模式，針對特定路段、特定異質性，建立一組可通用之列車當量值，提升運用上的便利性。除此之外，基本列車當量模式建立又因特性不同，需分為兩車種與多車種兩種不同之情境分別建構。在案例分析中，本研究先利用模擬法獲得不同參數條件下之列車延滯資料，搭配動態兩車種列車當量模式、動態多車種列車當量模式、固定兩車種列車當量模式與固定多車種列車當量模式等計算流程建立各列車當量值，結果顯示在兩車種與三車種之列車當量值皆有相同趨勢。本研究所提出之模式方法可廣泛應用於以延滯計算容量基礎之軌道系統，且藉由當量轉換後建立相同列車單位，協助鐵路系統準確的評估系統之容量，掌握系統的供需能量及服務水準。

A conventional railway system usually has multiple types of trains with various service patterns operating on the same line. This difference in train characteristics lead to different capacity impacts on the system. Recently a new concept was proposed to use Base train equivalent (BTE) standardize different train type into base train; this concept is similar to Passenger car equivalent (PCE) on highway. By convert these non-base trains to a standardized unit we call the convert volume as base train units (BTU). However, previous study focuses on the development of BTE with analytical capacity models as opposed to delay-based capacity models, such as parametric or simulation models. Consequently, this research develops delay-based BTE models for delay-based capacity models. Since BTE is developed based capacity models its value also varies with key capacity factors, such as traffic, operating and route characteristics. However, in terms of a particular route, BTE would only vary with traffic volume and heterogeneity since most of the other factors will be fixed. Therefore, this study first develops dynamic BTE models with consideration of volume and heterogeneity. Besides that, this study also develops fixed BTE model with consideration of heterogeneity since its impact is far more significant than traffic volume. Another variation in the development is the number of train types. For only two-type train operations, BTE can be directly computed based on the developed BTE models. However, the same model cannot be directly applied to multiple-type train operations (three or more types) due to due to limited output of variables from the capacity models. This study adopts the concept of vector projection to identify single value for each BTE in this case. With the proposed models, the unit of delay-based rail capacity can be converted into a standard unit. The impact of an additional train can be easily assessed, and capacity measurements from different lines or systems can be compared and evaluated.