Research on Harmonic Resonance in Traction Power-Supply System Containing a Thyristor-Based Neutral Section System

Harmonic resonance phenomenon was found in traction power-supply system (TPSS) after an automatic thyristor-based neutral section system (ATNSS) has been installed in Shenshuo Railway, China. Harmonic resonance usually occurs in the coupling system between the TPSS and the trains. However, no previous researches show the participation of the ATNSS. In this paper, with the concentration of the harmonic resonance of the coupling system, a solution is proposed to get the impedance vs frequency characteristics of TPSS. The influences of thyristor voltage-balancing parameters have been investigated based on MATLAB/Simulink, and the study of their impact on the power network voltage was carried out. The results show that adjusting dynamic voltage-balancing capacitors appropriately could effectively suppress the high-frequency resonant overvoltage of TPSS.