车网耦合的牵引供电系统谐波仿真分析

摘要

牵引供电系统是电力系统重要负荷，也是电力系统主要的谐波源之一。在研究牵引供电系统谐波传输特性和谐波对电力系统的影响时往往对牵引供电系统模型进行一定的简化，虽然具有一定的合理性，但是这样分析出来的结果与实际结果相比必然存在一定的误差。针对牵引供电系统谐波分析模型不精确，利用 PSCAD/EMTDC 搭建了电力机车-牵引网-电网仿真模型，仿真研究了机车位置、机车数量和牵引网长度变化时牵引供电系统谐振以及电网总谐波畸变率的特性。仿真结果表明该仿真模型能更准确地分析牵引供电系统谐波特性，分析结果更加符合实际。%Traction power supply system is an important load and one of main harmonic source of power system. Certain simplification is made on traction power supply system modeling when sudying the harmonic transmission characteristc of traction power supply system and the impact of traction power supply system harmonic in power system. Although simplified model has a certain rationality, there will be some errors in the analysis results based on simplified model compared with the actual results. According to the inaccuracy of traction power supply system model, the united model of electric locomotive and traction network and powe system is built by PSCAD/EMTDC software. The characteristics of traction power system resonance and the total harmonic distortion (THD) when the location and number of trains and the length of traction network change are studied. Simulation results show that the united model can more accurately analyze the harmonic characteristics of traction power supply system, and the analysis results are more realistic.