高速铁路接触网行波传播特性研究

Characteristics of Travelling Wave Propagation in Catenary of High-speed Railway

基于高速铁路接触网线路参数推导相模变换矩阵,并对接触网线路进行电磁解耦,计算得到行波各模量的衰减系数和相位速度。通过对衰减系数和相位速度频率特性研究发现,不同的频率分量和传输路径会造成不同的衰减和传播速度,因此,行波会在传播过程中出现色散现象,这给故障行波的准确提取带来困难。大地电阻率的变化对线模分量的衰减系数和相位速度影响不大,地模分量的衰减系数和相位速度随大地电阻率的增大而减小。在电磁暂态程序(EMTP)中建立基于频率相关参数的J.Marti线路模型。仿真结果表明故障行波的模2分量在故障点奇异性明显,适用于各种短路故障的行波故障测距。

On the basis of parameters of high-speed railway （HSR） catenaries , phase-mode transformation was proposed to carry out electromagnetic decoupling of HSR catenaries and to derive frequency characteristics of attenuation coefficients and phase velocities in the mode domain . Different frequency components and different transmission paths generated different attenuations and different velocities , which led to dispersion of travel-ling waves in propagation and to troubles in accurate extraction of faulty travelling wave components . Varia-tion of the earth resistivity had little effect on the attenuation coefficients and phase velocities of line modes whereas the attenuation coefficients and phase velocities of the earth mode decrease with increasing of the earth resistivity .The frequency-dependent J .Marti model was established by employing EMTP .The simulation re-sults show that the mode 2 component of the faulty travelling wave demonstrates remarkable singularity at the failure point and is so suitable for range measurement of travelling wave failures of short circuit types .