Low Frequency Stability of AC Railway Traction Power Systems: Analysis of the Influence of Traction Unit Parameters

Dynamic interactions between AC railway electrification systems and traction unit power converters can result in low frequency oscillation (LFO) of the contact-line voltage amplitude, which lead to a outage substation shutdown train traffic. Several system parameters influence stability system, including length such as transformer leakage inductance, DC-link capacitance, control bandwidths synchronization systems. This paper focuses on these LFO. The methodology is based frequency-domain analysis. Nyquist Bode diagrams are used determine limit. validation method performed through use time-domain simulations.