Traction power systems for electrified railways: evolution, state of the art, and future trends

Abstract

Traction power systems (TPSs) play a vital role in the operation of electrified railways. The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target. On the basis of sorting out the power supply structures of conventional AC and DC modes, this paper first reviews the characteristics of the existing TPSs, such as weak power supply flexibility and low-energy efficiency. Furthermore, the power supply structures of various TPSs for future electrified railways are described in detail, which satisfy longer distance, low-carbon, high-efficiency, high-reliability and high-quality power supply requirements. Meanwhile, the application prospects of different traction modes are discussed from both technical and economic aspects. Eventually, this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system, speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode, employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy.

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, stricter regulations are needed to deliver power to the subway. The traction power supply system for the MCS generally has the following technical features [12][13][14][15][16][17][18][19][21][22][23][24][25][26][27][28]:…”

“…The DC system traction power substation (TPS) consists of AC/DC converters including a rectifier transformer (RTT) and uncontrolled rectifier (SR). Transformer-rectifier groups (TSR) are in line with EN 50328, EN60146-1-1, NEMA RI9, and IEC 62590 connection schemes [12][13][14][15][16][17][18][19][21][22][23][24][25][26][27][28][45][46][47][48][49], for example, star, delta/delta, star-three-phase bridge; delta, star/star, delta-parallel bridge or series bridge; delta, star/double star-six-phase half wave with an interphase transformer (reactor); etc.…”

“…Power supply, including a bulk supply substation and an internal power distribution system, must comply with national or regional voltage standards, and must be synchronized with the existing urban railway planning system. The traction power demand estimation must ensure reliability and flexibility in cases of normal operation, overload, fault, and the development of the prevention of load [18,19].…”

Investigation of a 25 kV–50 Hz Railway-Substation Power Supply Based on a Back-to-Back Modular Multilevel Converter Topology

“…Looking at the research [34], we find that railway powering systems tend to use increasingly more power electronics to power the catenaries. However, few articles discuss These places are the most sensitive, and with the development of decentralized microgrids, we have to be sure that the distribution systems are not polluted by high harmonics [7] that could lead to issues in the power grid.…”

“…Looking at the research [34], we find that railway powering systems tend to use increasingly more power electronics to power the catenaries. However, few articles discuss industrial constraints.…”