Vehicle-Network Low-Frequency Coupling Characteristic and Suppression in High-Speed Railway

In view of the problem of low-frequency oscillation caused by the coupling of traction power supply system and high-speed train, a small-signal impedance model of traction power supply system and high-speed train was established. The stability of the vehicle-network system was analyzed by the impedance ratio criterion, and the mechanism of low-frequency oscillation was revealed. On this basis, the influence of the control parameters of the train grid-side rectifier on the low-frequency stability of the vehicle-network system was analyzed, and some basic conclusions and rules that have a guiding effect in suppressing low-frequency oscillation were obtained. Finally, the theoretical analysis is verified in experimental test.