Research on control strategy based vehicle-network coupling instability suppression measures

摘要

In recent years, more and more attention has been paid to the safe and stable operation of electrified railway, especially to the vehicle-network coupling stability, which focuses on the phenomena of high frequency resonance (HFR) and low frequency oscillation (LFO), which has become the research hotspot. Firstly, this paper studies the impedance model of the traction network and the train power system, and proposes the AF-RCS impedance model of the vehicle-network. Based on this model, from the perspective of grid-side converter control strategy, AOC inhibition measures are proposed to solve the instability of vehicle-network coupling caused by insufficient system damping. Furthermore, VCT inhibition measures were proposed to quickly reduce the damage of HFR to the system. Finally, the VCT-AOC comprehensive suppression strategy was proposed, which improved the damping ratio and enhanced the stability of the system while rapidly protecting the system. The effectiveness of the method is verified by simulation and experiment.