A Retrofit System and Method for Platform Screen Doors in Urban Rail Transit

To enhance the reliability and stability of platform screen door (PSD) systems in urban rail transit, this study proposes a novel retrofit system and corresponding methodology. The system incorporates three key modules: redundant circuit design, remote operation, and dual local control. In the event of a failure in the main control circuit, the system is capable of automatically switching to a backup control circuit. When the redundant circuit module itself malfunctions, remote operation will be activated, enabling operators to promptly minimize system disruptions. Additionally, two local control panels are installed on the platform, both equipped with priority interlock functionality, allowing either panel to control the platform screen doors on their respective sides. This architecture significantly enhances both the efficiency and reliability of the overall system.