Research and application of flexible starting method for metro trains with permanent magnet motors based on PI control

To further improve the performance and capacity of metro systems and ensure fast and smooth train starting, typically characterized by shortened starting durations and reduced jerks during starting, this paper proposes a flexible starting method for metro trains fitted with permanent magnet motors, based on a dynamic analysis of the train starting process. This solution focuses on optimizing cooperation among various subsystems during the starting process. As a result, it facilitates flexible starting for trains that effectively maintains and releases braking, while ensuring the effective implementation of traction instructions. To address train rollback protection and control, an incremental proportional-integral (PI) algorithm was introduced, by establishing an active rollback prevention and control system model specifically for the train starting process, this approach enhanced the robustness of train starting on inclined track sections. Performance simulations and real-world testing with complete metro trains have been conducted to verify the proposed flexible starting method on the entire line. Both simulation and testing results indicate the adaptability of this solution to various track conditions and its effectiveness in achieving smooth and rapid starting of metro trains powered by permanent magnet motors, without requiring modifications to existing equipment.