基于模态分析的牵引供电系统谐波谐振过电压研究

摘要

To deal with occurring of resonance over-voltages in the traction power supply system of high-speed railways,by analyzing the characteristics of harmonics and comprehensively considering the characteristics of distribution parameters and skin-effect of lines,the method for calculating the parameters of the traction network (a circuit consisting of contenary,feeding lines,rail-ground loops,loop conducting wires and feeding lines between traction substations and contenary) was studied and the equivalent model of the traction power supply system was built to calculate the line parameters of the traction power supply system.With the modal analysis method,the coupling relationship between the traction power network and electric locomotive was decoupled,the vehicle-network coupling based data such as the numbers of harmonic resonances,voltage waveforms and scope of influence and the mechanism of causing resonance over-voltages were determined.With software EMTP-ATP,the simulated vehicle-network coupling model based on EMU CRH2 and AT power supply mode was set up to acquire a good knowledge of the voltage situation of the traction power network in the coupling state.By comparison the simulation results are proved in agreement with the measured data,which verifies the correctness of the simulation model.%针对高铁牵引供电系统的谐振过电压问题,通过分析其谐波特性,综合考虑线路集肤效应及分布参数的特性,研究由接触网、馈线、钢轨回路(包括大地)、回流导线以及牵引变电所至接触网的馈电线等构成的牵引网的参数计算方法,建立牵引网线路等效模型,使用该模型计算牵引网线路参数；采用模态分析方法解耦牵引网与电力机车的耦合关系,确定基于车网耦合的牵引供电系统的谐波谐振次数、电压波形、影响范围等数据以及所引起的牵引网过电压机理；通过EMTP-ATP软件建立基于AT供电方式与CRH2型动车组的车网耦合仿真模型,得到牵引网网压状态.通过与实测的机车负荷、谐波电流等数据对比可知,仿真结果与实测数据分析结果一致,验证了该方法的正确性.