Analysis and Evaluation of Suppression Methods on Low-Frequency Oscillation in Electric Railways

In recent years, low-frequency oscillations of railway electrification systems caused by improper electric matching between high-speed trains and traction power supply systems have occurred frequently, which has a severe impact on the electrified railway. The research of the oscillations mechanism is very important to ensure power supply quality and stable operation of traction power supply system. In this paper, the traction network and train coupling model is established and the phenomenon of the low-frequency oscillations of railway electrification systems is reproduced, and the instantaneous power characteristics is analyzed. Then, the factors of the stability are analyzed according to the method of impedance ratio criterion. Three kinds of inhibition measures are analyzed through simulation verification, and concludes that low-pass filter feedback damping compensation is more advantageous. The work of this paper provides theoretical support for the actual governance of the low-frequency oscillation of the traction network and train coupling system in the electrified railway.