Novel high speed railway uninterruptible flexible connector based on modular multilevel converter structure

Author

Xu Tian ; Qirong Jiang ; Yingdong Wei ; Junmin Zhang ; Yitao Wei

Author_Institution

Dept. of Electr. Eng., Tsinghua Univ., Pingdingshan, China

fYear

2015

fDate

1-5 June 2015

Firstpage

952

Lastpage

958

Abstract

Phase sequence commutating method among traction feeders results in a neutral section without power supply between two feeders in traction substation of electrified railway. Electric locomotives suffer from a no-power time of more than 100 millisecond when going through the neutral section, during which the power failure and restoration process causes serious over-voltage and over-current problems. A novel railway uninterruptible flexible connector based on two-phase modular multilevel converter structure(MMC-UFC) is proposed in this paper, which can completely eliminate power supply dead zone. System utilization and operational principle are analyzed. Mathematical model of MMC-UFC is built to derive the difference between MMC-UFC. Double close-loop control strategies are given and close-loop control of both upper arm current and lower arm current for MMC converter is proposed to ensure the quality of output current. PSCAD/EMTDC simulations and experiment are carried out to prove the effectiveness of proposed MMC-UFC and its control system.

Keywords

closed loop systems; electric connectors; electric locomotives; failure analysis; overvoltage; power convertors; railway electrification; traction power supplies; uninterruptible power supplies; MMC-UFC; PSCAD-EMTDC simulation; double close-loop control strategy; electric locomotive; electrified railway traction substation; high speed railway uninterruptible flexible connector; modular multilevel converter structure; overcurrent problem; overvoltage problem; phase sequence commutating method; power failure process; power restoration process; power supply dead zone elimination; Capacitors; Connectors; Integrated circuits; Load modeling; Power supplies; Rail transportation; Substations; Uninterruptilbe flexible connector; high speed electrified railway; modular multilevel converter; neutral section;

fLanguage

English

Publisher

ieee

Conference_Titel

Power Electronics and ECCE Asia (ICPE-ECCE Asia), 2015 9th International Conference on

Conference_Location

Seoul

Type

conf

DOI

10.1109/ICPE.2015.7167896

Filename

7167896