Objective Shanghai Rail Transit Line 2 (hereinafter referred to as 'Line 2') adopts TBTC (track circuit-based train control) signaling mode during its construction period. After the line entered the stage for major signaling system overhaul, the signaling system is upgraded to 'TBTC+CBTC (communication-based train control)' mode. As the existing platform screen door system could not be linked with the signaling system, it is necessary to carry out a retrofit of the platform screen doors.

Method The basic conditions of the platform screen doors on Line 2 prior to retrofit are introduced. According to whether the platform screen doors are full-height platform screen doors, the retrofit project for the line is divided into four sections. After comparison, the retrofit scheme of 'immediate dismantling, immediate installation, and immediate commissioning for use' is adopted, and the preparatory work prior to retrofit is described. The implementation of door structure retrofit and control system retrofit for platform screen doors in different sections is elaborated, and the improvement in platform screen door capacity after the retrofit is summarized.

Result & Conclusion  The 'immediate dismantling, immediate installation, and immediate commissioning for use' scheme did not affect daily operations, ensuring normal train operation and passenger boarding/alighting during the retrofit period. After the completion of the retrofit along the entire line, trains on the line are equipped with DTO (driverless train operation with staff on board) functionality, other functions such as precise coordination between platform screen doors and train doors, as well as automatic door opening and closing are also realized.