MW-level grid-source-storage-locomotive coordinated traction power supply system with segmented DC bus: analysis and experimental investigation

• A MW-level modular grid-source-storage-locomotive coordinated traction power supply system based on segmented DC bus is proposed. • The topology and operating principle are proposed to achieve dynamic topology reconstruction and smooth scenario switching operation. • MC-MQPR control strategy is proposed to effectively suppress grid-connected current harmonics and compensate control delays. • The proposed grid-source-storage-locomotive coordinated traction power supply system exhibits superior performance in terms of robustness, power response, current tracking, and harmonic suppression. To achieve a green and clean traction power supply system (TPSS) in electrified railway, a MW-level grid-source-storage-locomotive coordinated TPSS (GSSL-CTPSS) based on segmented DC bus is proposed. Universal compatibility with all existing AC TPSS is achieved by the GSSL-CTPSS, and the integration of green energy (renewable energy and energy storage systems) is integrated without modification to the original infrastructure. Dynamic topology reconstruction and smooth scenario switching operation are achieved through the proposed topology and operating principle. A multiplex compensation multiple quasi-proportional resonance control strategy is proposed to suppress grid-connected current harmonics and compensate for control delays. Using the impedance-based method, the stability of the GSSL-CTPSS is analyzed. Typical operational scenarios of GSSL-CTPSS are established based on field test data, and the validation is conducted through a high-fidelity simulation and a full-power StarSim hardware-in-the-loop experiment test. The simulation and experimental results demonstrate that the proposed GSSL-CTPSS exhibits superior performance in terms of robustness, power response, current tracking, and harmonic suppression. Specifically, the phase margin has been increased by 43.51°, the dynamic response stability time is within 20 ms, and the total harmonic distortion of the current can be reduced by about 3% to 12%.