Influence of Infrastructure and Operating Conditions on Energy Performance of DC Transit Systems

Abstract

Energy efficiency is more and more important for modern electrified transportation systems, requiring an understanding of the various indexes of performance (regenerability, receptivity, and energy losses, thus including braking recovered energy and energy loss in catenary) and of the influence of the main system parameters (headway, line voltage, substation separation, etc.). By means of electromechanical simulation, the most relevant parameters and system conditions are identified as influencing the efficiency performance and optimization capability. Besides the assessment of such efficiency performance indexes, identifying their typical ranges of variation, one further outcome is the identification of characteristic system parameter combinations that lead to extreme variations in the system energy efficiency itself. Such peculiar variations are caused by occasionally synchronized patterns of trains along the line and result in a significant local increase or decrease in efficiency. Efficiency drop scenarios in particular should be taken into consideration for worst-case analysis and to devise effective mitigations. To this aim, the effect of differently distributed passenger stations is considered.

Hierarchical Operation Optimization for Regenerative Braking Energy Utilizing in Urban Rail Traction Power Supply System

“…The predicted current of train I 0 (t+1)* is derived as (9), and the residual correction e 0 (t+1)* is derived as (10):…”

“…According to the statistics, the RBE can reach approximately 35% of traction power consumption. Thus, improving its utilization is an important means for urban rail transit to contribute to the goal of "carbon peaking and carbon neutrality" [9]. EFSs are applied to contribute to the goal of "carbon peaking and carbon neutrality" [9].…”

“…Thus, improving its utilization is an important means for urban rail transit to contribute to the goal of "carbon peaking and carbon neutrality" [9]. EFSs are applied to contribute to the goal of "carbon peaking and carbon neutrality" [9]. EFSs are to invert RBE to the AC side, while also stabilizing the DC catenary network volt shown in Figure 1, the trains and TPSS operate independently, with trains runn cording to the timetable, and the TPSS flowing freely [10].…”

Measures and Prescriptions to Reduce Stray Current in the Design of New Track Corridors

“…In transit systems with large return current intensity, it is common practice for the rails of each track to be bonded together and for the tracks to be cross bonded to balance the traction return current, to reduce the resistance of the return path as well as to decrease the track potential and reduce the generation of stray current [67]. As an additional positive effect, the reduction in the return path resistance and the possibility of recirculate current between different tracks at intermediate points between TPSs and not only at TPSs contribute positively to energy efficiency, improving the exchange of regenerative braking energy (improving system receptivity) [68].…”

Feasibility Study of Traction Power Supply for Medium-Capacity Rail System Based on Rigid Overhead Conductor Rail System: Case Study on Pham Van Dong Route in Ho Chi Minh City, Vietnam

“…Therefore, it is very important that the design of traction power supply for new systems carefully considers the above issues. At the same time, applying new technology is necessary to avoid obsolescence and wasting capacity, and to improve system reliability and quality [22][23][24].…”