贯通式同相供电高速铁路牵引网馈线行波保护研究

Feeder travelling wave protection of continous cophase power supply high-speed railway traction network is the main studying target of this project. The main studying content and key science problem of the research is:①Studying the transmission characteristic of fault travelling wave in AT traction network、cophase supply traction substation and electric locomotive; ②Studying the method of evading for refraction and reflection of travelling wave, Studying the identificaton method of initial travelling wave and lightning interference, Studying the influence of the fault closing angle on travelling wave protection; ③Studying directional protective relaying based on comparison of travelling wave, traveling wave current directional protection with polarity comparison, directional protective relaying based on amplitude comparison of travelling wave; ④Studying the wide area backup protection of traction network based on travelling wave; ⑤Studying the interrelationship of electrical conversion equipment control system,electrical conversion equipment protection and feeder travelling wave protection, studying the interaction law. The research target is:inventing the identificaton method of initial travelling wave and lightning interference, inventing the high-frequency harmonics suppression means of travelling wave protection, inventing the voltage zero crossing fault detection method, inventing the directional protective relaying based on comparison of travelling wave, travelling wave current directional protection with polarity comparison, directional protective relaying based on amplitude comparison of travelling wave principle and action criterion, inventing the wide area backup protection principle and action criterion of traction network based on travelling wave, inventing the interaction law of electrical conversion equipment control system,electrical conversion equipment protection and feeder travelling wave protection.

项目围绕贯通式同相供电高速铁路牵引网馈线行波保护展开研究。主要研究内容和关键科学技术问题是：①研究AT牵引网、同相供电牵引变电所、电力机车负荷行波传播特性；②研究牵引网折反射行波识别困难的规避方法和故障初始行波与雷击、高次谐波等干扰的辨识方法，研究故障合闸角对行波保护的影响；③研究牵引网行波方向比较式纵联保护、行波电流极性比较式纵联保护、行波幅值比较式方向保护；④研究牵引网广域行波后备保护；⑤研究电能变换器控制系统、电能变换器保护、牵引网行波保护之间相互影响和相互配合的规律。研究目标是提出故障初始行波与雷击干扰辨识方法、行波保护对高次谐波抑制措施、电压过零点附近故障检测方法，提出牵引网行波方向比较式纵联保护、行波电流极性比较式纵联保护、行波幅值比较式方向保护的原理和动作判据，提出牵引网广域行波保护原理和动作判据，提出电能变换器控制系统、电能变换器保护、牵引网馈线行波保护之间相互配合的规律。

建立贯通式同相牵引供电系统仿真模型，根据现有的牵引供电系统线路参数建立牵引网模型，建立基于交—直—交变换器的三相—单相的牵引变电所模型，建立CHR2型交—直—交电力机车模型。研究适用于不平衡线路的相模分解矩阵和行波在牵引网中的传播特性，利用Carson理论计算牵引网线路参数，利用求得的参数和波动方程求解针对该不平衡线路的相模变换矩阵。基于集合经验模态分解与神经网络方法，对接地故障、雷击故障和雷击未故障进行识别。研究基于极点对称模态分解方法与支持向量机结合的雷击故障识别方法，该方法同样对IMF分量求取能量、相关系数和近似熵的特征向量，并使用支持向量进行雷击故障识别。通过行波保护原理和贯通式同相牵引直接供电系统相结合，提出了基于FEEMD的贯通式同相牵引带回流线直接供电系统牵引网行波幅值比较式方向保护、行波差动保护、行波方向比较式纵联保护三种保护方法。提出由牵引变电所出口处电容和区外一段接触线共同构成牵引网的物理边界，分析贯通式同相AT牵引供电系统及牵引网边界的频域特性模型。研究贯通式同相AT牵引供电系统牵引网及边界的频率特性，分析牵引网、牵引网边界对故障暂态信号高频分量的衰减作用，并给出牵引网对故障高频暂态量的衰减强度超过边界对故障高频暂态量衰减强度的牵引网长度临界值，及故障位置的改变对保护安装处检测到的故障高频暂态信号的影响。基于牵引网边界对暂态电流高频分量有很强的衰减作用，提出了一种贯通式同相AT牵引供电系统的牵引网单端电流方向暂态保护。提出一种基于压缩感知理论与二阶微分法相结合的贯通式同相AT牵引供电系统的牵引网单端电流保护方法。提出一种利用线路两端电流波形相似度的牵引网保护方案，从故障电流传播的折、反射过程、衰减程度、极性等角度出发，分析了线路内部故障和相邻线路故障时线路两端电流波形的相关性与差异性。