The Coupled Oscillation Between Catenary System And The Traction Drive System In High-Speed Train

With the development of high-speed railway, high speed trains generally use AC-DC-AC drive technology. The harmonic spectrum of four-quadrant pulse rectifier in traction drive system is wide and there are plenty of high-frequency harmonic components. The coupled oscillation between high-speed train and traction power supply system gradually emerges and brings great harm to the safe operation of the high-speed rail.Aimed to analyze the coupled oscillation mechanism between traction network and traction drive system and the key factors affecting the stability of the cascade system, the thesis starts from the harmonic propagation analysis to the traction network. It works out the spread of the harmonics by the node voltage matrix calculation in the chain network model. It studies the distribution parameter calculation of traction network and writes the harmonic calculation program. The network harmonic analysis theory and computational procedures are applied to the analysis of resonant accident which happened on the Beijing-Shanghai line when CRH380series EMUs are tested. Analysis results combined with the test data give a good interpretation to the cause of the accident. To study the amplification of harmonic currents, the singlet simplified model of the traction network is analyzed and the equivalent impedance is calculated by the formula derivation.This thesis introduces the impedance ratio criterion to analyze the stability of the cascade system. The output-input impendence ratio is described in the case of simplified network parameters and the factors affecting the stability of the cascade system are analyzed. Both the traction network and the single-phase PWM rectifier are modeled in MATLAB and the model of the cascade system is tested to study its stability. The thesis preliminarily studies the control strategy of rectifiers and the deadbeat control with digitally controlled delay is analyzed. Predictive current control method is proposed to solve the control delay impact. A low-power single-phase PWM rectifier platform is built and experiments are implemented to analyze different control strategies and the stability of the system.